Hill-Sachs and reverse Hill-Sachs lesions come in different shapes and sizes, and their effect on “glenoid track” can vary. Small Hill-Sachs lesions that do not engage can be successfully treated with a Bankart repair alone done arthroscopically or open. Moderate, engaging, Hill-Sachs lesions can be treated either with the addition of remplissage to an arthroscopic Bankart or by adding the triple blocking effect of the Bristow-Latarjet procedure.

Surface replacements vary in size from the small hemi-cap type of procedure to an entire humeral head replacement (HHR). These devices can be used as opposed to allograft replacement when the risk of post-reconstruction arthritis is high with the aforementioned more conventional treatment techniques. When 45% or more of the humeral head is involved with the lesion, or Outerbridge stage III and IV changes prevail, a HHR is preferred. An oval shaped HHR is the author's preference, and the long diameter can be used to provide coverage anteriorly or posteriorly and is particularly useful in large Hill-Sachs lesions associated with epilepsy.

The Hill-Sachs lesion is a bony defect of the humeral head that occurs in association with anterior instability of the glenohumeral joint. Hill-Sachs lesions are common, with an incidence approaching nearly 100% in the setting of recurrent anterior glenohumeral instability. However, the indications for surgical management are very limited, with less than 10% of anterior instability patients considered for treatment of the Hill-Sachs lesion. Of utmost importance is addressing bone loss on the anterior-inferior glenoid, which is highly successful at preventing recurrence of instability even with humeral bone loss. In the rare situation where the Hill-Sachs lesion may continue to engage the glenoid, surgical management is indicated. Surgical strategies are variable, including debridement, arthroscopic remplissage, allograft transplantation, surface replacement, and arthroplasty. Given that the population with these defects is typically comprised of young and athletic patients, biologic solutions are most likely to be associated with decades of sustainable joint preservation, function, and stability. The first priority is maximizing the treatment of anterior instability on the glenoid side. Then, small lesions of less than 10% are ignored without consequence. Lesions involving 10–20% of the humeral head are treated with arthroscopic remplissage (defect filled with repair of capsule and infraspinatus). Lesions greater than 20% that extend beyond the glenoid tract are managed with fresh osteochondral allografts to biologically restore the humeral head. Lesions great than 40% are most commonly associated with advanced arthritis and deformity of the humeral articular surface and are therefore treated with a humeral head replacement. This treatment algorithm maximises our ability to stabilise and preserve the glenohumeral joint.

The humeral component has a long track record of a low rate of humeral loosening. Moreover, there are significant challenges associated with removal of a failed cemented component.

Throckmorton reviewed the results of 76 total shoulder arthroplasties for osteoarthritis with minimum two year follow-up. There were incomplete lucent lines in 5/76 stems. None of the stem were judged to be at risk for loosening. Matsen published on the outcome of 131 shoulder arthroplasties for osteoarthritis with minimum two year follow-up. In this series, there were no components with shift or tilt.

In addition to strong literature support for the use of an uncemented humeral component, revision of a cemented humeral component can be very difficult with a risk of significant destruction of the humerus.

The cortex of the humerus tends to be thin and removing the cement can be similar to trying to remove concrete from an ice cream cone.

Therefore, the extremely low rate of loosening and the challenges associated with cemented components makes the non-cemented component the ideal humeral solution.

Hybrid fixation of total joint arthroplasty has been an accepted form of surgical approach in multiple joints. Principles of implant fixation should focus on durability providing secure long-term function. To date there is no conclusive evidence that pressed fit humeral stem fixation has an advantage over well-secured cemented humeral fixation. In fact, need for revision arthroplasty due to inadequate implant fixation has almost universally revolved around failure of cement fixation and loosening of the glenoid component. A case will be made based on 30 years of experience of one surgeon performing total shoulder arthroplasty using secure modern cement fixation techniques of humeral components. More recently, over the last 10 years, extremely high rate of durable secure glenoid implant fixation has been achieved using tantalum porous anchorage with polyethylene glenoid components. This has resulted in no cases of loosening of glenoid fixation and only 1 case of glenoid component fracture with greater than 95% survivorship over a 10 year period. A combination of well cemented humeral stem and trabecular metal anchorage of the glenoid has provided durable lasting function in primary total shoulder arthroplasty.

Before reverse shoulder replacement was an option for rotator cuff tear arthropathy the treatment modalities were limited to injections and physical therapy for pain control, arthroscopic debridement with or without biceps tenodesis/tenotomy and hemiarthroplasty. Functional improvement was limited with these treatment options and success for pain control was moderate at best. The destructive nature of the rotator cuff deficient shoulder continued with medialization of the glenoid and erosion of the acromion seen even after replacement with hemiarthroplasty. The end result usually left the patient with a pseudo paralysis of the shoulder region functionally and uncontrolled pain that made later revision with a reverse implant difficult or impossible.

Reverse arthroplasty was released for use in United States in 2004 for rotator cuff tear arthropathy. This initial procedure had a number of related complications that have been improved on over time with changes in implant design and better operative techniques. The long term results with reverse total shoulder arthroplasty have made this the procedure of choice for contained cuff tear arthropathy.

Rotator cuff arthropathy is a challenging problem to treat in many patients whose function remains intact despite pain from arthritis. In recent years, the introduction of reverse shoulder arthroplasty has improved the function and pain in pseudoparalytic shoulders with rotator cuff deficiency. However, significant evidence exists to support the use of alternative surgical and non-surgical treatments for those patients who suffer from the pain of arthritis while maintaining an intact force-couple of the rotator cuff and relatively well preserved function.

Large osteochondral defects of the glenohumeral joint are difficult to treat in young, active patients. When initial non-operative treatment with physical therapy, non-steroidal anti-inflammatory medications, corticosteroid injections, and viscosupplementation fails, surgery may become an option for some patients.

Traditional shoulder arthroplasty and hemiarthroplasty provide excellent function and pain relief that can be long-lasting, but these treatments are still very likely to fail during a young patient's lifetime, and results have been unsatisfactory in many younger patients. Microfracture and autologous chondrocyte implantation (ACI) have been used in the shoulder, but their use has been limited to small defects. Other techniques that incorporate soft-tissue coverage of larger osteochondral defects have the benefit of preserving bone, but have not provided consistently good results.

Advanced surgical techniques have been developed including all-arthroscopic osteochondral graft resurfacing of the humerus and glenoid for the treatment of osteoarthritis. This method of ‘biological resurfacing’ of the joint without using prosthetic implants may offer potential benefits to these young patients with shoulder arthritis including faster rehabilitation, pain relief, and easier revision surgery, if necessary. Early outcomes are encouraging in many cases, but inconsistent overall, with pain relief being the most reliable indicator of patient satisfaction.

Revision shoulder arthroplasty for failure secondary to soft tissue problems has improved with the availability of the reverse total shoulder system. The initial concept of a platform (convertible) stem was introduced in 2006. Removal of a well-fixed humeral stem can be a significant challenge and may require the surgeon to use osteotomy windows to successfully remove the implant. The increased time in the operating room, potential for complications and the cost of replacing the humeral component are all factors that make platform stem use a important consideration. The first report on total shoulder arthroplasty revision utilizing the platform stem concept confirmed improvements in patient morbidity and decreased costs. However, the overall functional improvement did not reveal a statistically significant improvement in pain relief or range of motion compared to those patients that had the humeral stem revised. Almost all major companies have adopted this concept of a convertible stem system for shoulder arthroplasty.

A primary goal of shoulder arthroplasty is to place the components in anatomic version. However, traditional instrumentation does not accommodate glenoid wear patterns. Therefore, many investigators have attempted to use computer modeling or CT-based algorithms to create custom targeting guides to achieve this goal.

There are some recent studies investigating the use of custom guides. Iannotti et al. published in JBJS-American in 2012 on the use of patient specific instrumentation. There were 31 patients included in the study. The authors found that the planning software and patient specific instrumentation were helpful overall, but particularly of benefit in patients with retroversion in excess of 16 degrees. In this group of patients, the mean deviation was 10 degrees in the standard surgical group and 1.2 degrees in the patient specific instrumentation group.

Throckmorton presented a study at the AAOS in 2014 on 70 cadaveric shoulders. There was one high volume surgeon (>100 shoulder arthroplasties a year), two middle volume surgeons (20–50 shoulder arthroplasties a year), and two low volume surgeons (less than 20 shoulder arthroplasties per year). Overall, the custom guide was significantly more accurate than standard instrumentation. The custom guides were found to be especially more accurate among specimens with associated glenoid wear. There were no strong trends to indicate consistent differences between high, medium, and low volume surgeons. The authors concluded that custom guides have narrower standard deviation and fewer significant errors than standard instrumentation.

Custom guides continue to evolve for use in shoulder arthroplasty including some guides that allow the surgeon to decide intra-operatively between anatomic shoulder arthroplasty and reverse arthroplasty. Additional studies will be necessary to further define the role of patient specific instrumentation in practice.

Management of bone loss on both sides of the glenohumeral joint has been made much easier by the introduction of the reverse shoulder arthroplasty (RSA). While traditional posterior bone grafting and newer augmented glenoid components are still being used for Walch type B2 glenoids, there is movement and the trend towards using the reverse prosthesis with Bone Ingrowth Offset (BIO-RSA) techniques. Bone loss on the humeral side can be managed by the prosthesis itself, fresh matched or frozen proximal humerus allografts, femoral shaft allografts, or tibial strut allografts. Several cases will be shown to illustrate each technique.

The incorporation of platelet rich plasma (PRP) in the treatment of various musculoskeletal conditions has increased exponentially over the past decade. While described most often as an augment or treatment for tendinopathies and acute tendon injuries, more recently, PRP has been described as an adjunct to arthroplasty procedures, mostly with respect to knee arthroplasty. In the shoulder, only a single study has been published, in which Zavadil and colleagues performed a randomised study of 40 patients undergoing total shoulder arthroplasty undergoing either treatment with autologous platelet gel and platelet poor plasma (n=20) or undergoing no biologic treatment (control group, n=20). The authors noted that the treatment group had significantly lower pain scores, less pain medication requirements, and improved internal rotation when compared to controls; in addition, there were no significant differences in post-operative (compared to pre-operative) hemoglobin levels or length of stay. The vast majority of arthroplasty studies discussing PRP analyze the impact of treatment on wound healing, post-operative pain, post-operative range of motion, and need for post-operative blood transfusions. Unfortunately, due to the substantial variability of methodology (not all PRP preparations are the same) in the available studies as well as the variability in outcomes reporting, direct comparison between different studies is not feasible. Here, we discuss the basic science elements of PRP relevant to arthroplasty, the variability of PRP solutions, the specific applications of PRP in arthroplasty, and the latest clinical outcomes analyses of patients undergoing PRP therapy in conjunction with shoulder arthroplasty.

The primary goals of successful rTSA (Reverse Total Shoulder Arthroplasty) are pain relief, improved shoulder motion and function with the restoration of patient independence. These goals can be achieved by optimal prosthesis design and surgical technique.

Historically there have been two predominant reverse shoulder design philosophies: the traditional valgus 155-degree neck-shaft angle with a medialised center of rotation introduced by Dr. Grammont, and the more recent varus 135-degree neck-shaft angle with a lateralised center of rotation, developed by Dr. Frankle. The latter design has reported lower incidences of scapular notching, coupled with improved adduction and external rotation. Over time, an understanding of the factors which resulted in clinical complications and those that contributed to the clinical success of both these design philosophies has been analyzed and widely publicised. With the currently available reverse prostheses the surgeon is required to be committed to one design philosophy or the other. This commitment to one singular design may hinder surgeons from the ability to individualise each case regardless of patient anatomy, rotator cuff condition, arthritic state and post-operative expectation.

Recently, a system has been launched which offers both design philosophies in one system, providing unsurpassed intra-operative flexibility. This allows the surgeon to adapt to each individual case and choose either design philosophy based on patient condition and anatomy, thus optimizing patient outcome.

The treatment of proximal humeral fractures has historically included Hemi Arthroplasty (HA) or Total Shoulder Arthroplasty (TSA). However, rTSA has recently become the surgery of choice for many fracture treatments based on more reproducible results. Certain implant characteristics are gaining favor in the treatment of proximal humerus fractures namely:

Press fit humeral stems - which avoid the risks of cement in-between the tuberosities which has been reported to compromise healing.

Intra-operative complications vary from extremely benign such as glenoid vault penetration to life and limb threatening for example brachial artery injury. Most intra-operative complications can be avoided with careful pre-operative planning, anticipation, and execution. However, even the best planning and execution including fluoroscopic guided reaming cannot prevent all complications. The following intra-operative complications will be discussed in detail in regards to both prevention and management: Glenoid vault penetration, Glenoid component malposition - reverse and primary, Glenoid fracture - reverse and primary, Humeral component malposition - reverse and primary, and Humeral fracture - reverse and primary.

Total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA) are excellent surgical options for individuals with shoulder arthritis, providing good to excellent results in the vast majority of patients. Complications are rare, but can be devastating for both the patient and surgeon. An uncommon, but extremely problematic complication following shoulder arthroplasty is shoulder stiffness. While substantial literature discussing post-arthroplasty stiffness is available for other joints such as the hip, knee, and elbow, there is a paucity of research available discussing this complication in the shoulder. As noted in multiple reviews, diminished range of motion following TSA or RSA may be due to a number of factors, including pre-operative diagnosis of proximal humerus fracture, inadequate post-operative rehabilitation, implant-related factors such as malpositioning and/or inappropriate-sized implants, and heterotopic ossification. Often, pathology leading to post-arthroplasty stiffness involves scarring of the long head of the biceps tendon, rotator cuff impingement, as well as cuff tendonitis. Periprosthetic joint infection (PJI) is also important to recognise, and may be difficult to diagnose, especially in cases of Propionibacterium acnes infections. Importantly, PJI may present with stiffness as well as instability, and thus a high index of suspicion with a low threshold to aspirate is necessary in these challenging patients. Treatment of patients with stiffness following arthroplasty is challenging, and may involve arthroscopic intervention with or without manipulation, as well as manipulation under anesthesia alone. This paper will discuss the etiology, work-up, and treatment of patients with shoulder stiffness following TSA and RSA.

The key to management of instability when performing total shoulder arthroplasty is to recognise the potential for instability, and avoid the pitfalls which may lead to it post-operatively. Instability can result from incompetent capsular or rotator cuff soft tissue envelopes. It may also result from muscular imbalances, as well as incompetent bony architecture (severe posterior wear causing extreme retroversion, or anterior glenoid loss from fracture) extreme retroversion or improper placement or fixation of implants.

Keys to providing a stable environment include performing careful soft tissue releases and providing muscular balance about the reconstructed arthroplasty; placement of implants in proper version; appropriate tensioning (height) and sizing (avoiding undersizing or overstuffing) of implants; recognizing incompetent rotator cuff substance or function and providing more stable, constrained implants (reverse total shoulder arthroplasty), when necessary.

Keys to recognizing potential instability, tips and pearls for intra-operative and post-operative surgical management will be provided.

Reverse total shoulder arthroplasty has become popular for primary replacement in complex proximal humerus fractures. Hemiarthroplasty and open reduction and internal fixation (ORIF) with locked plating were the treatment of choice but with variable functional outcomes and concerns of glenohumeral arthritis, rotator cuff problems, and tuberosity healing difficulties. This is especially concerning in the older population that has a higher incidence of rotator cuff problems and poor bone quality. Reverse total shoulder arthroplasty has resulted in excellent pain relief and seems to have a more consistent functional outcome in early reports when compared to hemiarthroplasty.

Infection after shoulder surgery is an infrequent but devastating complication with a reported incidence from 0 to 4%. A careful history is critical because many patients have a history of a “stitch abscess” or “superficial wound infection”. Prop. Acnes is the most common organism responsible for infection following rotator cuff surgery, instability surgery, ORIF proximal humerus fractures, and shoulder arthroplasty. This organism typically does not start to grow until Day 5, therefore it is critical to keep cultures a minimum of 10 to 14 days.

The diagnosis can be challenging, principally among patients undergoing revision surgery. The majority of patients with a low grade infection do not have blatant signs of infection such as erythema or sinus tracts. Pre-operative lab values as well as intra-operative pathology have been shown to be unreliable in predicting who will have positive cultures at the time of revision surgery.

There is an assortment of options for treating a patient with a post-operative infection. Important variables include the timing of infection, status of the host, the specific organism, status of implant fixation, and the status of the rotator cuff and deltoid. One of the most frequently employed options for treating the infected shoulder arthroplasty is two stage re-implantation. However, the rate of complications with this technique as well as residual infection remains high.

A panel of experts in the field of shoulder surgery/arthroplasty will be presented challenging case studies. They will discuss, dissect and analyze these cases from the perspective of appropriate work-up, clinical management, surgical approach and aftercare. A variety of cases representing the spectrum of pathology not uncommonly presenting to the surgeon caring for complex shoulder conditions will be discussed. Indications for nonsurgical and surgical interventions with consideration for various forms of arthroplasty will be presented and debated by the panel.

Complication rate after total shoulder arthroplasty ranges around 10%. These can be divided into intra-operative and post-operative complications. Intra-operative complications are periprosthetic fracture, nerve injury and malpositioning of components. Post-operative complications are instability, infection, rotator cuff tear, periprosthetic fracture, aseptic loosening, stiffness, heterotopic ossification and implant dissociation. The most effective means of preventing a complication are meticulous pre-operative planning, experience of the surgeon, adherence to sound surgical technique and intelligent patient selection and education.

Removal of a well-fixed humeral component during revision shoulder arthroplasty presents a challenging problem. If the humeral component cannot be extracted simply from above, an alternate approach must be taken that may include compromising bone architecture to remove the implant. Two potential solutions to this problem that allow removal of the well-fixed prosthesis are making a humeral window or creating a longitudinal split in the humerus.

A retrospective review was performed at the Mayo Clinic to determine the complications associated with performing humeral windows and longitudinal splits during the course of revision shoulder arthroplasty. This study included 427 patients from 1994–2010 at Mayo Clinic undergoing revision shoulder arthroplasty. From this cohort, those who required a humeral window or a longitudinal split to assist removal of a well-fixed humeral component were identified. Twenty-seven patients had a humeral window produced to remove a well-fixed humeral component. Six intra-operative fractures were reported from this group: 5 were in the greater tuberosity and 1 was in the distal humeral shaft. At the latest radiographic follow-up, 24 of 27 windows healed, 2 patients had limited inconclusive radiographic follow-up (1 and 2 months), and 1 did not have follow-up at our institution. Twenty-four patients underwent longitudinal osteotomy to extract a well-fixed humeral component. From this group, 1 had intra-operative fracture in the greater tuberosity. At most recent radiographic follow-up, 22 of 24 longitudinal splits healed, 1 had short follow-up (1 ½ months) with demonstrated signs of healing, and 1 did not have follow-up at our institution.

In both groups, there were no cases of window malunion and no components have developed clinical loosening. Data from this study suggests humeral windows and longitudinal splits can assist with controlled removal of well-fixed humeral components with a high rate of union and a low rate of intra-operative and post-operative sequelae.

Total shoulder arthroplasty (TSA) is an excellent surgical solution for patients with shoulder arthritis, providing good to excellent results in the vast majority of patients. Complications are rare, however, when they occur, can be devastating for both the patient and surgeon. An increasingly recognised complication of TSA is glenoid component failure. In a recent review of nearly 4000 shoulder arthroplasties, symptomatic glenoid component loosening occurs at a rate of 1.2% per year, while asymptomatic radiolucent lines occur at a rate of 7.3% per year. In addition, keeled glenoid components have been found to have an increased incidence of radiolucent lines compared to pegged glenoid components at both short and longer-term follow-up. Further, pegged glenoid components are associated with a lower risk of revision arthroplasty compared to keeled glenoid components. In a separate study of approximately 4600 shoulder arthroplasties, metal-backed glenoid components were found to have significantly lower rates of radiolucent lines, radiographic loosening, and component failure compared to all-polyethylene glenoid components. Despite these findings, however, metal-backed components are significantly more likely to require revision surgery (3:1) compared to all-polyethylene components. For the failed TSA due to glenoid component failure, revision with glenoid reimplantation may be considered, but is associated with a high rate of recurrent glenoid loosening. Alternatively, revision to a reverse shoulder arthroplasty, is feasible, but is technically demanding with high complication and reoperation rates. This paper will discuss the etiology, work-up, and treatment of patients with glenoid component failure following TSA.

The importance of mitigating pain for patients undergoing total shoulder arthroplasty is extremely relevant for purposes of being able to initiate early functional rehabilitation and activities of daily living. The process, however, does not commence after surgery but rather before surgery. Careful patient education and instruction, including pre-operative exercises to maximise mobility, strength and endurance within the limited range of motion is quite helpful. Adjunctive therapy includes preemptive ultrasound-guided intrascalene regional anesthesia, immediate post-operative peri-incisional injection of liposomal bupivacaine, post-operative use of waterproof Tegaderm^TM dressing to allow warm showers early on in the rehabilitation period, peri-operative use of Cox 2 inhibitors and a gentle, therapist-guided passive exercise program focusing on relaxation techniques. This in combination with patient-controlled analgesic pumps, careful surgical technique providing adequate soft tissue releases and removal of potential pain generators such as the long tendon of the biceps and an arthritic AC joint all contribute to the minimization of the patient's pain experience, and offers relatively early weaning from parenteral narcotics in the first 24 hours, and oral narcotics within the first 7–10 days post-operatively.

Subscapularis repair and integrity after a primary total shoulder arthroplasty is critical for successful outcomes. One should be familiar with the 3 basic takedown and repair techniques commonly utilised. Subscapularis repair after reverse shoulder arthroplasty is not as critical and in some cases may be detrimental to return of external rotation strength and motion.

Subscapularis tenotomy: The tendon is incised approximately 1 cm from the lesser tuberosity and an oblique incision is created from proximal lateral to distal medial stopping at the sentinel vessels. A combination of tendon-to-tendon figure of 8 sutures.

Lesser tuberosity osteotomy: This approach is helpful not only in obtaining a bone-to-bone healing, but also in the exposure. Osteotomies range from a fleck of bone in patients with minimal deformity, to a C-shaped osteotomy including part of the head which facilitates exposure of the posterior glenoid. Despite an ability to document radiographic healing of the lesser tuberosity fragment, this technique does not prevent fatty infiltration of the subscapularis.

Subscapularis Peel: This repair requires tendon healing to bone and probably incomplete, in most cases, reconstitution of a normal enthesis. External rotation can be gained by recessing the subscapularis insertion medially with the arm in external rotation. While bone-to-tendon sutures are the gold standard, augmentation of the sutures using a prosthesis as the anchor has led to the development of prostheses with multiple holes. Dual row repair of the tendon, however, may lead to medial rupture.

Most presentations about total knee arthroplasty begin with a statement that the procedure has been one of the great successes of modern surgery. However, not all patients consider their total knee a success. Success requires that patients experience relief of arthritic pain, return of function, and express satisfaction with the result. Patients need to be aware of the limitations of implants and accept reasonable expectations for the arthroplasty. If they don't, your next revision will likely be on a unsatisfied patient who had unrealistic expectations. The surgeon who operated on the patient for the primary intervention may feel obliged to try to make it better. Don't make that mistake. Avoid your next revision by only intervening when there is a clear indication.

In a recent patient survey, 15–20% of patients (and maybe more) were not completely satisfied with their arthroplasty in spite of having recent implant designs. It is a fact that some patients will not be satisfied with any intervention. Fibromyalgia, depression, high narcotic use for arthritic pain, secondary gain (e.g., Worker's Compensation claims pending) are some of the conditions that predict a difficult post-operative course and an unsatisfied patient who will push for revision. To avoid your next revision, choose patients wisely and make sure they understand that the total joint is a poor substitute for the normal knee.

Design surgeons and engineers have developed techniques for a specific implant system to minimise the problems of malrotation, malalignment, instability, anterior knee pain, stiffness, loosening and polyethylene wear. Surgeons should be careful to use the recommended implantation philosophy and technique to avoid these problems. Choose implant systems with a proven track record. Learn how and why to use the instruments correctly. Study a system well and know the nuances. If you don't know the system well enough, take a course from the designers and ask questions. Avoid your next revision by using a prosthesis system as it was intended.

Prosthetic joint infection remains a major reason for revision. Some patients have a greater chance of developing infection. Attention to detail from pre-operative preparation to rehabilitation will minimise, but cannot eliminate, the occurrence of infection. The recently published International Consensus on Prosthetic Joint Infection contains recommendations that should be followed to minimise the chance of infection. Avoid your next revision by following the recommendations to minimise the chance of infection.

The indication for revision is diagnosis of a problem that can be corrected with surgery. If a patient is satisfied with a result, revision surgery would only rarely be indicated regardless of the radiographic result. (Severe wear would be an exception to this.) Avoid you next revision by recognizing that “the enemy of good is better”.

Measured resection approach (anatomic) is based on the patients' unique anatomy adjusting for worn cartilage or bone loss. The femoral component is aligned around the primary transverse distal femoral axis around which the tibia follows a multi-radius of curvature. The tibia cut is made according to the patient's native anatomy adjusting for worn cartilage and bone loss, and applying an anatomic amount of tibial slope. This technique minimises the need for partial ligamentous releases to a large degree preserving the competence of the patient's soft tissue, though ligament and capsular releases can be used in difficult cases. Adjustments for the varus/valgus (up to 3 degrees) or slope of the tibial bone cut (3–10 degrees) further aids in knee balancing. The final alignment may not agree with a neutral hip-knee-ankle mechanical alignment on full length standing x-rays, leaving varus knees in slight varus, and valgus legs in neutral. Since little balance is required this operation can be performed in less than 40 minutes.

The goals of total knee arthroplasty are to restore the mechanical axis of the knee and create equal and symmetric tension on the ligaments throughout an arc of motion. What surgical technique best achieves this goal remains controversial.

In gap balancing, the extension space is created (distal femur and proximal tibia) and balanced. The flexion space and femoral component rotation are then set by placing tension on the collateral ligaments. This allows the femoral component to be rotated to create an equal and symmetric flexion gap based on the tension of collateral ligaments rather than arbitrary bony landmarks. In the measured resection technique, fixed bony landmarks are utilised to set femoral component rotation. Bony landmarks are subject to variations in patient's anatomy and inconsistency of the surgeon to reliably and reproducibly locate them during surgery. Fehring et al demonstrated that 49% of knees using bony landmarks had rotational errors of greater than 3 degrees. A recent study determined that the amount of femoral component rotation necessary to create a balanced flexion gap varied based on the amount of ligament release required, calling into question the validity of using this technique to set femoral component rotation. Additionally, a study by Dennis et al, showed that setting femoral component rotation based solely on bony landmarks leads to asymmetry in the flexion gap and excessive condylar lift off in flexion in over 60% of knees performed with a measured resection technique.

Osteoarthritis of the knee is commonly a disease which afflicts more than one compartment of the knee so medial compartment arthritis is almost always associated with patellofemoral and or lateral compartment disease to a lesser extent. In a review of 250 consecutive osteoarthritic knees strictly unicompartmental involvement occurred in less than 15% of affected knees. To segmentally replace one compartment when more than one is involved may lead to a suboptimal result from the compartmental replacement as well as lead to pain and failure with mid- to long-term follow up. The long term results with tricompartmental replacement continue to show success rates in the order of 90–95% at 15–20 year follow-up with multiple designs and fixation types. Additionally failure to replace the patella, although popular in Europe, has led to increased anterior knee pain in studies in North America. The disadvantage of tricompartmental knee replacement is the extent of surgical trauma compared to compartmental replacement although newer less invasive approaches may lead to similar recovery to compartmental replacement.

Total knee replacement (TKR) is considered the “gold standard” treatment for advanced osteoarthritis (OA) of the knee with good survivorship and functional outcomes. However up to 20% of patients undergoing TKR may have unicompartmental disease only. Treatment options for medial compartment arthritis can include both unicompartmental knee replacements (UKR) and TKR. While some surgeons favor TKR with a proven track record, others prefer UKR due to more normal joint kinematics, better proprioception and better motion. There is also a higher rate of return to sports amongst patients with UKR compared to TKR.

When considering all knee procedures, partial knee replacements account for 7–9%, primary TKRs for 83–88%, and revision knee replacements for 5–8%. Unicompartmental Knee Replacements comprise more than 90% of all partial knee replacement procedures. Proponents of UKR cite as advantages the preservation of normal knee kinematics, lower peri-operative morbidity, blood loss and infection risk compared with TKRs, as well as accelerated patient rehabilitation and recovery. However, partial knee replacements have a higher rate of revision than TKRs. This may be partly because they are inserted in patients with higher expectations, and partly because they are easier to revise. As a result, the volume of UKRs implanted has diminished over time and continues to decline.

We compared patient reported outcomes, satisfaction and perception of normality of the knee post-operatively between UKR and TKR. A single unit and single surgeon series of patients were recruited. Data was collated for 68 well-matched patients with more than 24 months follow-up. UKR was undertaken in patients with isolated medial compartment osteoarthritis; stable ACL and less than grade 3 lateral patellar changes of the Outerbridge classification. TKR was undertaken for the rest. The patients were assessed with validated knee scores including the Total Knee Function Questionnaire (TKFQ) which focuses on recreational and sporting outcomes as well as activities of daily living (ADL). Patient satisfaction and perception of knee normality was measured on a visual analogue scale.

Thirty-four patients with a TKR and 34 patients with a UKR were analyzed. The average ages in the TKR and UKR groups were 69.25 and 67.26 years, respectively. The patients were well-matched for demographics and had equivalent pre-operative morbidities and scores. The UKR group had better WOMAC (p=0.003), SF36 (physical: p<0.001 mental: p=0.25), Oxford knee (p<0.001) and Knee Society scores (p=0.002, function: p<0.001). The UKR group showed better outcomes in the TKFQ including exercise and sport (p= 0.02), movement and lifestyle (p=0.02) and the ADL (p=0.002). There was, however, no difference in patient satisfaction scores (p=0.41) and perception of how normal the knee felt between the two groups (p=0.99).

A UKR procedure confers better functional outcome in terms of recreation and sport compared to TKR procedures. While UKR is an appropriate choice in the elderly yet active patient with unicompartmental knee arthritis, satisfaction is similar to that of patients with a TKR reflecting higher pre-operative expectations. We believe that in appropriate centers, the UKR procedure is associated with excellent outcomes. UKR should have a secure place in the knee arthroplasty armamentarium provided current knowledge regarding patient selection and surgical technique is followed.

Total knee arthroplasty (TKA) is a successful operation associated with a high rate of clinical success and long-term durability. Cementless technology for TKA was first explored 30 years ago with the hope of simplifying the performance of the procedure and reducing an interface for potential failure by eliminating the use of cement. Poor implant design and the use of first generation biomaterials have been implicated in many early failures of these prostheses due to aseptic loosening and reflected the failure of either the tibial or patellar component. Despite this, many excellent intermediate and long-term series have clearly demonstrated the ability of cementless TKA to perform well with good to excellent survival, comparable to that of cemented designs.

Lessons learned from the initial experiences with cementless technology in TKA have led to improvements in prosthetic design and materials development. One of the most innovative biomaterials introduced into orthopaedics for cementless fixation is porous tantalum. Compared to other commonly used materials for cementless fixation, porous tantalum has the highest surface friction against bone, optimizing initial stability at the implant-bone interface as a prerequisite for long-term stability of the reconstruction.

At the 2013 AAOS Annual Meeting, Abdel presented the 5-year Mayo Clinic experience with cementless TKA utilizing a highly porous monoblock tibial component in 117 knees and found NO difference in survivorship compared to cemented fixation with a re-operation rate of 3.5% in both groups. They had no revisions for aseptic loosening. These early to intermediate results reflect our own experience with all cementless TKA utilizing a cobalt-chromium fibermesh femoral component, as well as monoblock porous tantalum tibial and patellar components with up to 11-year follow up. In that series of 115 patients, there was a 95.7% survival of implants, with no revisions of any components for aseptic loosening.

Further advantages to using cementless fixation include the elimination of concerns with regard to monomer-induced hypotension, thermal necrosis from PMMA polymerization, and third body wear secondary to retained or fragmented cement. Savings are also realised from elimination of the costs of cement, a PMMA mixing system, cement gun, pulse lavage system, and irrigation solution. Perhaps the greatest cost savings is derived from the reduction in operating room time. At our institution–a Level 1 county trauma center with an orthopaedic residency training program–we typically spend an average of 19 minutes of operating room time for the cementing of a total knee arthroplasty. Our average time expended for insertion of all three cementless implants is 47 seconds–representing a significant savings in the hospital operating room time charge. From the standpoint of the patient, the shorter operating time reduces the time under anesthesia, the blood loss, the risk of venous thromboembolism, as well as the infection risk–optimizing the conditions for a reduction in post-operative complications, directly impacting a potential reduction in morbidity and mortality.

Overall, the performance of all cementless TKA at our facility is cost-saving, is easily performed and reproduced by orthopaedic residents, and brings potential advantages to the patient in the form of a reduction in complications and an improvement in outcomes. Cementless fixation is the wave of the future, and the future is now.

There has been a recent increase in interest for non-cemented fixation in total knee arthroplasty (TKA), however, the superiority of cement fixation is an ongoing debate. Whereas the results based on Level III and IV evidence show similar survivorship rates between the two types of fixation, Level I and II evidence strongly support cemented fixation. United Kingdom, Australia, Sweden, and New Zealand registry data show lower failure rates and greater usage of cemented than non-cemented fixation. Case series studies have also indicated greater functional outcomes and lower revision rates among cemented TKAs. Non-cemented fixation involves more patellofemoral complications, including increased susceptibility to wear due to a thinner polyethylene bearing on the cementless metal-backed component. The combination of results from registry data, prospective randomised studies, and meta-analyses support the current superiority of cemented fixation in TKAs.

Cement Technique: 1. Proper exposure with adequate length of incision; 2. Pulsatile lavage to the cut to clean the cancellous bone; 3. Drill holes in the sclerotic bone surfaces; 4. Heated Simplex cement at a doughy state; 5. Apply cement on the cut bony surfaces including the posterior femoral condyles and pressurised, apply cement on the components as well and; 6. Further pressurization in extension with trial insert.

Total knees today are performed with the use of standard trials that the surgeon utilises to define appropriate implant rotation, range of motion, and soft tissue balance.

This “feel” based approach is very subjective, and lacks a quantifiable approach to interpret our intra-operative knee assessment.

Sensor-based trials are embedded into the specific knee designed tibial trial, and wirelessly displays data related to the implant's position and ligament tension.

The surgeon can now identify malrotation, soft tissue imbalance, and instability through a full ROM. The surgeon can see dynamic responses to ligament releases, alignment changes, and implant adjustments. As Insall taught us; a TKR is a soft tissue procedure, and a “balanced” knee will demonstrate improved outcomes and greater patient satisfaction. Smart Trials allow us to discuss how our intra-operative techniques affect our patient's outcomes.

This surgery will utilise Smart Trials during a Cruciate Retaining TKR.

Obesity is clearly a worldwide epidemic with significant social, health care and economic implications.

A clear association between obesity and the need for both hip and knee replacement surgery has been demonstrated. Specifically the presence of class 3 obesity (BMI > 40) increases the incidence of THA by 8.5 times and the incidence of TKA by 32.7 times, compared with patients of normal weight.

Issues related to TJA in the morbidly obese include:

Outcomes - There is a growing body of evidence to support the premise that patients undergoing either THA or TKA who are morbidly obese derive significant benefit from the surgical intervention. Specifically patient and disease specific outcome measures (WOMAC, SF-12, KSCRS, HSS) demonstrate equal change between pre-operative and post-operative scores in those patients of normal weight compared to the morbidly obese cohort.

There is little debate that performing total joint arthroplasty in the morbidly obese is technically challenging and that the potential for increased peri-operative morbidity, particularly in the form of infection is present. That being said, the realised benefit to the patient of the surgical intervention is significant, and denying surgery on the basis of obesity alone is not justified.

The goals of any rehabilitation protocol should be to control pain, improve ambulation, maximise range of motion, develop muscle strength, and provide emotional support. Over 85% of TKA patients will recover knee function regardless of which rehabilitation protocol is adopted but the process can be facilitated by proper pain control, physical therapy, and emotional support. The remaining 15% of patients will have difficulty obtaining proper knee function secondary to significant pain, limited pre-operative motion, and/or the development of arthrofibrosis. This subset will require a special, individualised rehabilitation program, which may involve prolonged oral analgesia, continued physical therapy, more diagnostic studies and occasionally manipulation. Controlling pain is the mainstay of any treatment plan. The program described herein has been used at Ranawat Orthopaedics over the last 10 years in more than 2000 TKAs.

There are a multitude of choices and implant varieties for primary total knee arthroplasty (TKA). TKA implant systems differ in a number of design characteristics intended to either improve performance through optimizing kinematic function (such as the medial pivot, mobile bearing, gender-specific or high-flexion designs) or by increasing the durability of the TKA by minimizing long-term failure modes, such as wear and osteolysis with highly cross-linked polyethylene.

Further adding to the complexity of choice, is the re-emergence of cementless fixation in response to improve longevity in the progressively younger TKA patient population. The patella creates additional decision-making in TKA, as while most surgeons in the US resurface the patella, there are some who routinely do not which is a much more commonly accepted practice outside of the US. Finally, metal hypersensitivity is a controversial, yet unavoidable issue, which forces the consideration of “nickel-free” or ceramic-coated implants. Unfortunately, there is paucity of outcome data to support one implant choice over another, which is problematic in the modern arena of value-based cost reductions in healthcare.

Further confounding the issue is the inability of current outcome measures to accurately assess the differences in performance of the various TKA designs. This talk will provide the latest evidence particular to the major TKA component choices as they relate to patient pathology.

Most discussions of alignment after TKA focus on defining “malalignment”; the prefix mal- is derived from Latin and refers to bad, abnormal or defective and thus by definition malalignment is bad, abnormal or defective alignment. No one then wants a “malaligned” knee. The intellectually curious, however, might switch the focus to the other end of the spectrum and ask what does an ideally aligned knee look like in 2015? Is there really one simple target value for alignment in all patients undergoing TKA? Is that target broad (zero +/−3 degrees mechanical axis) or is it a narrow target in which a penalty, in regard to durability or function, is incurred as soon as you deviate even 1 degree? Is that ideal target the same if we are evaluating the functional performance of the TKA versus the durability of the TKA or could there be 2 different targets, one that maximises function and one that maximises durability? Is that target adequately described by a single 2-dimensional value (varus/valgus alignment in the frontal plane) as measured on a static radiograph? Is that value the same if the patient has a fixed pelvic obliquity, a varus thrust in the contralateral knee or an abnormal foot progression angle?

It is revealing to ask “do we understand TKA alignment better in 2015 than in 1979…?” Maybe not. We allowed ourselves over the past 2 decades to be intellectually complacent in regard to questions of ideal alignment after TKA. The constraints on accuracy imposed by our standard total knee instruments and the constraints on assessment imposed by 2-dimensional radiographs made broad, simple targets like a mechanical axis +/− 3 degrees reasonable starting points yet we have not further worked to verify if we can do better. It is naïve to think that the complex motion at the knee occurring in 6-dimensions over time can be reduced to a single static target value like a neutral mechanical axis and have strong predictive value in regard to the success or failure of an individual TKA. We assessed 399 knees of 3 different modern cemented designs at 15 years and found that factors other than alignment were more important than alignment in determining the 15-year survival.

Until more precise alignment targets can be identified for individual patients or sub-groups of patients then a neutral mechanical axis remains a reasonable surgical goal. However, the traditional description of TKA alignment as a dichotomous variable (aligned versus malaligned) defined around the broad, generic target value of 0 +/− 3 degrees relative to the mechanical axis is of little practical value in predicting the durability or function of modern TKA.

Limb deformity is common in patients presenting for knee arthroplasty, either related to asymmetrical wear patterns from the underlying arthritic process (intra-articular malalignment) or less often major extra-articular deformity due to prior fracture malunion, childhood physical injury, old osteotomy, or developmental or metabolic disorders such as Blount's disease or hypophosphatemic rickets. Angular deformity that is above the epicondyles or below the fibular neck may not be easily correctable by adjusted bone cuts as the amount of bone resection may make soft tissue balancing impossible or may disrupt completely the collateral ligament attachments.

Development of a treatment plan begins with careful assessment of the malalignment which may be mainly coronal, sagittal, rotational or some combination. Translation can also complicate the reconstruction as this has effects directly on location of the mechanical axis.

Most intra-articular deformities are due to the arthritic process alone, but may occasionally be the result of intra-articular fracture, periarticular osteotomy or from prior revision surgery effects. While intra-articular deformity can almost always be managed with adjusted bone cuts it is important to have available revision type implants to enhance fixation (stems) or increase constraint when ligament balancing or ligament laxity is a problem.

Extra-articular deformities may be correctable with adjusted bone cuts and altered implant positioning when the deformity is smaller, or located a longer distance from the joint.

The effect of a deformity is proportional to its distance from the joint. The closer the deformity is to the joint, the greater the impact the same degree angular deformity will have. In general deformities in the plane of knee are better tolerated than sagittal plane (varus/valgus) deformity.

Careful pre-operative planning is required for cases with significant extra-articular deformity with a focus on location and plane of the apex of the deformity, identification of the mechanical axis location relative to the deformed limb, distance of the deformity from the joint, and determination of the intra-articular effect on bone cuts and implant position absent osteotomy.

In the course of pre-operative planning, osteotomy is suggested when there is inability to correct the mechanical axis to neutral without excessive bone cuts which compromise ligament or patellar tendon attachment sites, or alternatively when adequate adjustment of cuts will likely lead to excessive joint line obliquity which can compromise ability to balance the soft tissues.

When chosen, adjunctive osteotomy can be done in one-stage at the time of TKA or the procedures can be done separately in two stages.

When simultaneous with TKA, osteotomy fixation options include long stems added to the femoral (or tibial) component for intramedullary fixation, adjunctive plate and screw fixation, and antegrade (usually locked) nailing for some femoral osteotomies. Choice of fixation method is often influenced by specific deformity size location, bone quality and amount, and surgeon preference. Surgical navigation, or intra-operative x-ray imaging methods (or both) have both been used to facilitate accurate correction of deformity in these complex cases.

When faced with major deformity of the femur or tibia, with careful planning combined osteotomy and TKA can result in excellent outcomes and durable implant fixation with less constraint, less bone loss, and better joint kinematics than is possible with modified TKA alone.

Both the patient and the surgeon want hip and knee arthroplasties to last a lifetime. As a result, many patients have been told to defer arthroplasty as long as possible. After arthroplasty, many patients have been advised to limit physical activity. Such management strategies prioritise longevity but compromise lifestyle. Given that the technical aspects of the arthroplasty are satisfactory, modern total hip and knee prostheses have demonstrated remarkable durability. Quantitative studies of patient activity have measured up to 48 million cycles in vivo, with impact, without evidence of loosening, osteolysis, or other impending failure. These data suggest that with current technology, an active lifestyle is compatible with implant longevity.

This session will present a series of challenging and complex primary and revision cases to a panel of knee arthroplasty experts. A variety of cases representing the spectrum of not uncommonly presenting pathologies will be discussed in terms of appropriate work-up, clinical management, surgical approach, and aftercare. This will be an interactive case-based session that at its conclusion should leave the attendee with a more thorough approach to these challenging issues.

There are many reasons that the surgically inclined orthopaedic surgeon should be responsible for the medical management of osteoarthritis of the knee. These include: 1) The non-operative treatment of OA is often highly effective for all stages of the disease; 2) A non-operative treatment program is the best preparation for a successful surgical outcome; and 3) Patients appreciate a surgeon's interest in their overall care and are likely to return if surgery is needed; 4) Medicare and many insurance companies are refusing to pay for a TJA until many months of conservative management has been administered.

There are many potential causes of pain in an arthritic knee. These include intra-articular (e.g. degenerative meniscal tears, loose bodies, synovitis) and extra-articular (tendonitis, e.g. ilio-tibial band syndrome, bursitis, muscle overload syndromes and referred pain) sites. The potential sources of pain in an arthritic knee produce a wide range of symptoms that are not necessarily correlated with objective measurements (e.g. x-rays, MRI). Moreover, the natural history of an arthritic knee is unpredictable and variable.

The treatment of the young, arthritic knee patient of all stages requires a systematic and consistent non-surgical approach. This approach includes the use of: 1) analgesics/anti-inflammatory agents; 2) activity modification; 3) alternative therapies; 4) exercise; 5) injections/lavage. The response to each form of non-surgical treatment is unpredictable at each stage (Kellgren 1–4) of OA. The placebo effect of each form of treatment, including the physician-patient interaction, is 50–60% in patients with mild-moderate OA.

The components of a non-operative treatment program include: 1) Education-emphasizing the importance of the patient taking charge of his/her care; 2) Appropriate activity/life style modifications-emphasizing the importance of remaining active while avoiding activities that aggravate symptoms (e.g. running to biking); 3) Medications-oral, topical, intra-articular; 4) Physical therapy. There are extensive data to support each of these interventions. The AAOS has issued guidelines based upon a review of the literature-based effectiveness of conservative interventions.

This video presentation serves to illustrate the pertinent aspects of bone preparation and implant insertion in cementless total knee arthroplasty (TKA) utilizing porous tantalum as a fixation surface integral to the success of the procedure.

The patient is typical of the surgical candidate frequently encountered for arthroplasty—a 60-year-old female with three compartment osteoarthritis of the knee, and manifesting a 10-degree varus deformity and 5-degree flexion contracture. She is a limited community ambulator without the use of support.

A standard surgical exposure is utilised and the bone preparation is identical to that used in the fixation of cemented implants—no alignment guides, cutting guides, or referencing instrumentation is used that is unique in the femoral or tibial bone preparation. The principal difference is in the patellar preparation. Instrumentation unique to the cementless porous tantalum patella is utilised in order to achieve three goals: a composite implant/residual bone thickness that replicates the thickness of the native patella, the generation of a planar patellar resection that is parallel to the anterior cut of the femur, and secure initial stability of fixation.

Keys to the initial fixation of the porous tantalum tibial and patellar components include the high surface friction of the material against bone, as well as the interference between the hexagonal pegs of each implant within the fixation holes (which are dimensionally smaller in diameter than the major and minor dimensions of the peg geometry). Care must be instituted to ensure that no bone or soft tissue debris is interposed at the mating surfaces of the implants that would compromise interface contact, and to carefully suction the peg holes to ensure that no debris impedes the complete seating of the pegs and the prosthesis. Lastly, all mating surfaces at the implant/bone interface must approach each other in a parallel fashion to optimise contact between the fixation surfaces and the bone resection surfaces.

The procedure is simply, easily performed, and is time saving. Total elapsed time for insertion of all three TKA implants in this video is 90 seconds.

I never considered this to be a significant problem if it is noticed. (back to that later)

Aaron Rosenberg's report seems to have agreed, but at the last members meeting of the Knee Society, Boston, September 2009, others had experience that contradicted my view.

With their experience, ultimately the results were very substantially compromised. This video and presentation show you how to avoid a bad result, actually obtain a perfect result, if you or your student assistant, resident or fellow, bags the MCL.

There are three important points. (1) One needs to recognise the occurrence. (2) The setting is usually varus and so direct end-to-end repair cannot be depended upon. (3) Use of a semitendinosis tenodesis, together with an imperfect, distracted direct repair works perfectly well!

(1) Recognition: The setting is usually varus, but I have had one case in which the chief resident, working with the fellow succeeded in getting the MCL in a valgus knee! In this usually tight varus setting the key feature is that at some point in the case, before component placement, one notices that the exposure is all of a sudden better! Now, the guilty resident or just a passive assisting resident/fellow will usually disagree. The extension space is not so obviously lax, but the flexion space is. Secondly, you do not feel an intact ligament in flexion. And, to prove it I have had to do a little more exposure of the superficial MCL to show the tear. There are at least three mechanisms. Most common is a saw cut. Next is possibly injury with the scalpel or cutting cautery during exposure, and last is damage essentially pre-operatively by a very sharp medial osteophyte which has thoroughly abraded the ligament.

Laxity in full flexion is not necessarily obvious as the posterior capsular integrity helps hide the instability. Again, the really intact ligament is well felt, and in the situation of laceration, the tibia pulls forward more on the medial side, the medial flexion space opens, and what was usually a tight exposure gets suddenly better.

(2) When varus is the setting, I have found it impossible or at least uncomfortable to depend upon direct repair. When the soft tissues are needing to be released or simply undergoing more stress than usual and a lot more than on the lateral side, I see it as unwise to expect or depend upon only a medial repair to hold.

(3) The semitendinosis tenodesis has worked essentially perfectly in every one of my cases. These patients have had no post-operative instability and they have had better than average to extremely good ROM.

A presumably key point is not to alter the patient's post-operative regimen! And, to avoid some passive alteration of PT, I advise specifically that the surgeon or those in his/her team do not mention the occurrence to the patient, the family or the PT! I put the whole story in the op-note, and weeks later I will specifically tell the patient what the staple in place is all about.

The major benefit of TKA with tourniquet is operating in a bloodless field. A possible secondary benefit is a better cement bone interface for fixation.

The disadvantages of tourniquet use for TKA include multiple risk factors both local and systemic: Nerve damage; Altered hemodynamics with limb exsanguinations (15–20% increase in circulatory volume) and reactive hyperemia with tourniquet release (10% increase in limb size increasing soft tissue tension and secondary pain); Delay in recovery of muscle function; Increased risk of DVT with direct trauma to vessel walls and increased levels of thrombin-antithrombin complexes; A 5.3× greater risk for large venous emboli propagation and transesophageal echogenic particles; Vascular injury with higher risk in atherosclerotic, calcified arteries; Increase in wound healing disturbances.

Our initial experience with TKA without tourniquet was in high risk patients with previous DVT or PE, multiple scarring, or compromised cardiovascular status. We have used this method on all patients for the last eight years. The protocol includes regional anesthesia, incision and approach made with 90-degree knee flexion, meticulous hemostasis, jet lavage and filtered carbon dioxide delivered to dry and prepare bone beds for cementation, application of topical tranexamic acid and routine closure. We have encountered no differences in blood loss or transfusion rates, less post-operative pain, faster straight leg raise and knee flexion gains, and fewer wound healing disturbances. We recommend TKA sans tourniquet. Let it bleed!

Computer navigation is an attractive tool for use in total knee arthroplasty (TKA), as it is well known that alignment is important for the proper function of a total knee replacement. Malalignment of the prosthetic joint can lead to abnormal kinematics, unbalanced soft-tissues, and early loosening. Although there are no long term studies proving the clinical benefits of computer navigation in TKA, studies have shown that varus alignment of the tibial component is a risk factor for early loosening.

A handheld, accelerometer based navigation unit for use in total knee replacement has recently become available to assist the surgeon in making the proximal tibial and distal femoral cuts. Studies have shown the accuracy to be comparable to large, console-based navigation units. Additionally, accuracy of cuts is superior to the use of traditional alignment guides, improving the percentage of cuts within 2 degrees of the desired alignment.

Because the registration is based on the mechanical axis of the knee, anatomic variables such as femoral neck-shaft angle, femoral length, and presence of a tibial bow do not affect the results. The handheld aspect of this navigation unit allows its use without additional incisions or array attachment. Furthermore, the learning curve and usage time is minimal, supporting its use in primary TKA.

Wound closure is typically not the surgeon's favorite part of the case. It is critical, however, for preventing infection, avoiding early re-operation and is the portion of the procedure that is most directly visible to the patient. The purpose of this study was to investigate the use of bidirectional, barbed suture for wound closure in primary total hip (THA) and knee arthroplasty (TKA) to determine whether its use is safe, cosmetic and associated with time savings when compared with traditional suture.

We carried out a blinded, randomised controlled trial comparing bidirectional, barbed suture (Quill™ SRS; Angiotech Pharmaceuticals) and a traditional absorbable layered closure following primary THA and TKA. We randomised 20 THAs (10 Quill; 10 traditional) and 31 TKAs (16 Quill; 15 traditional). Power analysis determined that a minimum of 23 patients per arm of the study were required to show a significant difference in closure times using an alpha of 0.05 and a beta of 0.80.

Wound closure in the Quill group was significantly faster than traditional suture by a mean of 4.1 minutes (9.2 vs. 13.2 minutes; p = 0.0005). Traditional closure required a mean 5.6 sutures, compared to a mean 2.7 sutures (p < 0.0001). The unit cost of the barbed suture was 5–12 times that of conventional suture. One patient who had undergone Quill closure developed a superficial reaction that was managed non-operatively.

Our results have been confirmed by a similar recently published randomised study by Gilland et al, who showed a mean reduction in closure time of 4.7 minutes. However, these authors concluded that overall costs were lower with a barbed suture based on a reduction in operative times. This method of closure has also been shown to provide a stronger and more water-tight closure than traditional interrupted sutures.

In primary TKA, non- or semi-constrained TKA implants might have their limitations in the absence of collateral ligaments, severe deformity, large osseous defects and gross flexion-extension instability.

Although most primary TKA indications can be solved with modular, non-hinged implants, an adequate balancing might require a relevant soft tissue release. This consequently adds complexity and operative time with less predictable results in the elderly patient. The current literature reporting on short- to mid-term results of rotating hinged implants in primary osteoarthritis shows some quite diverse results and consequently different interpretations of this implant type in primary knee arthroplasty. Although some authors were able to show good and excellent clinical results in 91% of patients and consequent survival rates of a rotating hinge implant after 15 years up to 96% in primary indications, others found high complication rates of up to 25% of all operated patients, which remains unclear for us and is inconsistent with our clinical results in primary and revision TKA in over 30 years of experience with the ENDO-Model rotating hinge implant.

Our potential indications in the elderly for a rotating or pure hinged implant in primary TKA include: Complete MCL instability; Severe varus or valgus deformity (>20 degrees) with necessary relevant soft tissue release; Relevant bone loss including insertions of collaterals; Gross flexion-extension gap imbalance; Ankylosis; One staged implantation with specific antibiotics after PJI.

Due to general limited soft tissues or hyperlaxity, patients with neuropathic joints, or lack of extensor mechanism should be considered for a complete hinged implant. The ENDO-model hinge has only been minimally adapted since its development in the 70´s, including fully cemented long stems, in modular and non-modular versions. We strictly reserve a rotational hinge in primary indications for patients >70 years with a combined varus alignment, whereas in severe valgus deformities, a complete hinged implant version should be used for our implant design.

Infected TKA is one of the most challenging complications of knee surgery, but spacers can make them easier. An articulating spacer allows partial weight bearing and range of motion of the knee during rehabilitation. This spacer is made using antibiotic-impregnated bone cement applied to the implant. For our purpose, 4.8 g powdered tobramycin is mixed with 2 g vancomycin and one batch of cement. Cement is applied early to the components, but applied late to the femur, tibia, and patella to allow molding to the defects and bone without solid adherence to bone. Patients have tailored intravenous antibiotic therapy for 6 weeks for treatment of various gram-positive and gram-negative organisms. At 10–12 weeks patients receive a cemented revision total knee arthroplasty using standard cementing techniques. From our experience range of motion before reimplantation is 5–90 degrees. Follow-up averaged 73 months for 50 patients with 90% good to excellent results, 10% may have a recurrence. Use of an articulating spacer achieves soft tissue compliance, allows for ease of operation, reduced post-operative pain, improved function, and eradicates infection equal to standards reported in the literature.

Surgical exposure during revision total knee arthroplasty is the most essential part of the procedure. An appropriate surgical exposure protects the extensor mechanism, facilitates safe implant removal and allows for accurate reimplantation of components and appropriate soft tissue balancing. The pre-operative plan is critical to achieving appropriate exposure in the revision setting. Evaluating the skin and previous incisions and determining range of motion will aid in deciding which exposure technique is most appropriate.

The key to exposure in revision total knee arthroplasty is patience. Approximately 90% of revision total knees can be adequately exposed with a standard medial parapatellar arthrotomy, a proximal medial tibial exposure, complete synovectomy and clearing of the medial and lateral gutters. The patella need not be everted in the revision setting and extreme care must be taken to protect the extensor mechanism. In cases where standard exposure techniques are inadequate or may jeopardise the extensor mechanism, a quadriceps snip may be performed. This takes tension off the stiff knee, is easy to repair and does not require limitation of rehabilitation protocols. The tibial tubercle osteotomy is utilised in patients with extreme stiffness and to aid in removal of well-fixed tibial components. General principles include keeping the osteotomy fragment long (8–10 cm) and leaving a lateral periosteal bridge and soft tissue attachment to aid in repair and healing of the fragment. Other techniques such as the quadricepsplasty or V-Y turndown may be utilised but are rarely needed.

An expert panel of orthopaedic surgeons is going to be evaluating primary and revision total hip and total knee replacements submitted by the audience. Participants will present the x-rays and clinical findings of difficult cases for which they are seeking an expert opinion from the panel. The panel will probably have conflicting opinions which will lead to an entertaining and educational session. The moderator will also provide some extremely challenging cases once again, to stimulate more controversy. This session has been very popular in the past and is fast moving, humorous and educational.

Total joint arthroplasty (TJA) has historically been considered primarily an inpatient operation. However, the actual length of stay (LOS) has diminished over time. At our institution the LOS from 1987 to 1990 averaged five to seven days. This decreased to three days from 1993 to 2002 and down to one to two days from 2005 to 2011. With the adaptation of improved anesthesia and pain management protocols, minimally invasive surgery techniques, rapid recovery protocols, and proper patient selection, outpatient (OP) TJA appears to be the next step in maximizing peri-operative efficiency; especially as younger patients are undergoing TJA. Other potential benefits of OP TJR include improved patient care and control, better patient and surgeon satisfaction and a lower overall cost.

Over a twenty-four month period (July 2012 to June 2014) we performed 250 primary TJAs (139 hips and 111 knees) and twelve revision TJAs (six hips and six knees). All patients received 400 mg of celecoxib pre-operation and 200 mg/day for ten days. In addition to general anesthesia, hips received a short-acting spinal and knees received an adductor canal block. Tranexamic acid (IV or topical) and a pericapsular injectable cocktail of liposomal bupivacaine was routinely used. There was one deep infection (0.4%) and one readmission for pain control (0.4%). Two cases of deep vein thrombosis were diagnosed (0.8%).

Patient education, home health care utilization, and proper patient selection are key factors to keep hospitalization rates, emergency room visits, and re-admission rates to a minimum.

To resurface or not to resurface the patella… that is the question. It all comes down to where you practice. It is controversial in that there is a risk of possible complications from resurfacing versus the potential for simply having complaints of pain which may supposedly arise from the anterior knee stemming from the unresurfaced patella.

The evolution of more favorable anatomic femoral component designs which are very friendly to the patellofemoral articulation have resulted in lower patella resurfacing complications. The insertion of appropriately externally rotated tibial and femoral components, if not reducing anterior knee pain, have certainly minimised the risk of resurfaced patella complications. Also, with current surgical techniques of component insertion, the lateral release rate is extremely low, thus avoiding the possibility of avascularity developing in the resurfaced patella. This complication will almost completely be eliminated if the patella thickness is kept greater than 13 mm after patella resection.

In my experience, patella complications from the resurfaced patella are extremely rare. Many unicompartmental knees require re-operation because of the development of progressive patellofemoral arthritis. Re-operation from anterior knee pain from progressive arthritis from the unresurfaced patella has given inferior results. Overall, meta-analysis data demonstrates decreased satisfaction, increased anterior knee pain and higher early revision rates in the unresurfaced group. National joint registries, especially the Australian registry support routine resurfacing; complications are low and outcomes are improved.

Even though there exists controversy as to whether the patella should be resurfaced or not, there is an overwhelming consensus in the U.S. that there is little downfall nowadays with respect to resurfacing the patella.

Total knee replacement (TKR) is one of the most successful procedures in orthopaedic surgery. Although originally limited to more elderly and less active individuals, the inclusion criteria for TKR have changed, with ever younger, more active and heavier patients receiving TKR.

Initially, tibial components were cemented all-polyethylene monoblock constructs. Subsequent long-term follow-up studies of these implants have demonstrated excellent durability in survivorship studies out to 20 years. Aseptic loosening of the tibial component was one of the main causes of failure in these implants. Polyethylene wear with osteolysis around well-fixed implants was rarely (if ever) observed. Cemented metal-backed nonmodular tibial components were subsequently introduced to allow for improved tibial load distribution and to protect osteoporotic bone. Long-term studies have established that many one-piece nonmodular tibial components have maintained excellent durability.

Eventually, modularity between the polyethylene tibial component and the metal-backed tray was introduced in the mid-80s mainly to facilitate screw fixation for cementless implants. These designs also provided intra-operative versatility by allowing interchange of various polyethylene thicknesses, and also aided the addition of stems and wedges. Other advantages included the reduction of inventory, and the potential for isolated tibial polyethylene exchanges.

Since the late 1980's, the phenomena of polyethylene wear and osteolysis have been observed much more frequently when compared with earlier eras. The reasons for this increased prevalence of synovitis, progressive osteolysis, and severe polyethylene wear remain unclear, but there is no question that it was associated with the widespread use of both cementless and cemented modular tibial designs.

Mayo Data: Modular versus All Polyethylene Tibial Components in Primary TKA: The study population included 10,601 adult (>18 years) patients with 14,524 primary TKR procedures performed at our institution between 1/1/1988 and 12/31/2005. Mean age was 68.7 years and 55% were female. Overall revision rates and revisions for loosening, wear/osteolysis were compared across different designs using Cox proportional hazards regression models adjusting for age, sex, calendar year and body mass index (BMI). Over an average 9 years follow-up, a total of 865 revisions, including 252 tibia revisions were performed, corresponding to overall survival of 89% (Confidence intervals (CI): 88%, 90%) at 15 years. In comparison to metal modular designs, risk of tibial revision was significantly lower with all-poly tibias (HR 0.3, 95% CI: 0.2, 0.5). Overall, posterior cruciate-retaining (CR) designs performed better than the posterior-stabilised (PS) designs (p=0.002). With any revision as the endpoint, there were no significant differences across the 18 designs examined. Similarly, there were no significant differences across the 18 designs when we considered revisions for aseptic loosening, wear, and osteolysis. Among patient characteristics, male gender, younger age, higher BMI were all significantly associated with higher risk of revisions (p<0.008).

Available data support the use of nonmodular tibial designs in TKR in order to prevent or reduce the chance of backside wear, third body particles from resulting metallic debris and associated polyethylene induced osteolysis. In all patients, (not just older individuals) use of an all polyethylene tibial component is an attractive and more cost effective alternative, and is associated with the best survivorship and lowest risk of revision.

Two big problems exist with the all-polyethylene cemented tibial component—the polyethylene and the cement. The polyethylene is too weak and flexible to bear tibial load, so it deforms and loosens. Isoelastic material has never worked, and it never will. The interface stresses are too high when two flexible structures are poorly bonded and heavily loaded. Critical review of the literature fails to make a convincing case for use of cement in TKA. Many studies demonstrate clinical, mechanical, and biological failure when cement is used for fixation. Work by Ryd et al. has shown that initial migration within the first few months diminished rapidly after the first 6 months with virtually no additional movement for years after. They also found that cemented components do not remain rigidly fixed to bone long-term, but loosen enough to move 0.2 to 2.1 mm at the bone-cement interface with provocative testing. Although bone-ingrowth tibial components migrate slightly more initially than cemented ones do, they stabilise and do not sink progressively. Screw fixation adds rigidity, but does not seem to improve results. Rigidity of initial fixation is the most important feature after alignment to ensure pain-free function after arthroplasty, and can be achieved with press-fit techniques in TKA. Several early reports of bone-ingrowth TKA had inferior results because the tibial component had no stem, peg, or screw fixation, leading to implant migration and loosening. An effective stem has been shown to greatly improve tibial component fixation. The cut upper surface of the prepared tibia has areas that are too weak to withstand the forces that are applied to the surface, and failure in compression is likely unless fixation is augmented. An effective stem also reduces the shear and tensile loads at the bone-prosthesis interface. The effectiveness of compression or compaction of the tibial cancellous bone with an appropriately sized tibial metaphyseal stem has been shown, and probably was a major factor in the long-term success of fixation in our series.

Clinical results of TKA with osteointegration techniques for fixation of the femoral and tibial components in our series are comparable with the best series reported with cemented fixation. Many recent studies show significant advantages of osteointegration over cement fixation in TKA. Fixation of implants with PMMA pressed into cancellous bone eventually loosens, and fixation of a metal component to bone cement also is tenuous in most cases. Cement is disappearing rapidly from use in total hip, ankle, and shoulder arthroplasty, and soon will be replaced with osteointegration technique in the knee. Perhaps the most appealing aspect of bone-ingrowth TKA is bone preservation. The ease of revisability because of good bone was encouraging in the components that wore, loosened, or became infected in the current series of TKA. These knees are functioning as well as knees with primary TKA. Should these knees develop additional problems, progressive destruction of bone is unlikely to occur, even if repeated revision is necessary.

Contemporary techniques to perform total knee arthroplasty use either conventional instrumentation with intramedullary and extramedullary referencing or use a computer navigation system that requires insertion of femoral and tibial tracking pins and an intra-operative registration process. Much of the initial enthusiasm for computer navigation in TKA has waned as many of these systems have proved cumbersome, time consuming and expensive with no substantial evidence of a clinical benefit. Patient specific instrumentation is an additional option that is now widely available which seeks to harness some of the accuracy of computer navigation while improving intra-operative surgical efficiency. In 2015 there are now patient specific options available from multiple vendors and these vary in several different ways including: alignment goals; imaging modality; pin guide vs. cutting guide; all plastic vs. metal-plastic composite; and the degree of surgeon input into pre-operative planning. In all systems but one alignment is typically set relative to the mechanical axis; one system uses so-called kinematic alignment. Imaging can be done via CT, MRI, or MRI in conjunction with a hip-knee-ankle radiograph. The guides that are produced are typically made of a plastic material and in some cases are meant only to position pins onto which traditional metal cutting guides are then placed. In some systems the plastic guides come pre-assembled with an integrated metal cutting-guide that allows resection of the distal femur or proximal tibia in one step; in other systems cutting is intended to be carried out through a plastic captured guide. Finally there is wide variability in the degree of surgeon involvement in the pre-operative planning for the guides, ranging from no involvement in the so-called kinematic approach all the way to the ability for surgeons to dictate the depth, location, flexion-extension angle, varus-valgus angle, and rotation in some systems. At this point relatively little comparative data exists to objectively compare one system versus another.

Surgeons most likely to find substantial benefit from patient specific instrumentation are those who perform moderate numbers of TKA each year but who have inconsistent surgical scrub teams. For those surgeons, substantial surgical inefficiency can be attributable to the scrub team's unfamiliarity with the complex instrumentation needed for TKA. Patient specific instrumentation can bypass many of those relatively complex instruments and allow the surgeon to complete TKA in a timely and efficient manner. For TKA subspecialists, patient specific instrumentation may have an appeal from a precision standpoint or from an ease-of-room turnover perspective but are unlikely to yield major intra-operative time savings at this point. In the future, combining patient specific instruments with size-specific disposable instruments that are financially and environmentally favorable may make this technology more applicable to even broader groups of surgeons.

To progress to a same day surgery program for arthroplasty, it is important that we examine and resolve the issues of why patients stay in the hospital. The number one reason is fear and anxiety for the unknown and for surgical pain. The need for hospital stay is also related to risk arising from comorbidities and medical complications. Patients also need an extended stay to manage the side effects of our treatment, including after-effects of narcotics and anesthesia, blood loss, and surgical trauma. The process begins pre-operatively with an appropriate orthopaedic assessment of the patient and determination of the need for surgery. The orthopaedic team must motivate the patient, and ensure that the expectations of the patient, family and surgeon are aligned. In conjunction with our affiliated hospitalist group that performs almost all pre-admission testing, we have established guidelines for patient selection for outpatient arthroplasty. The outpatient surgical candidate must have failed conservative measures, must have appropriate insurance coverage, and must be functionally independent. Previous or ongoing comorbidities that contraindicate the outpatient setting include: cardiac – prior revascularization, congestive heart failure, or valve disease; pulmonary – chronic obstructive pulmonary disease, or home use of supplemental oxygen; untreated obstructive sleep apnea – BMI >40 kg/m2; renal disease – hemodialysis or severely elevated serum creatinine; gastrointestinal – history or post-operative ileus or chronic hepatic disease; genitourinary – history of urinary retention or severe benign prostatic hyperplasia; hematologic – chronic Coumadin use, coagulopathy, anemia with hemoglobin <13.0 g/dl, or thrombophilia; neurological – history of cerebrovascular accident or history of delirium or dementia; solid organ transplant. Pre-arthroplasty rehabilitation prepares the patient for peri-operative protocols. Patients meet with a physical therapist and are provided with extensive educational materials before surgery to learn the exercises they will need for functional recovery. Enhancement of our peri-operative pain management protocols has resulted in accelerated rehabilitation. The operative intervention must be smooth and efficient, but not hurried. Less invasive approaches and techniques have been shown to decrease pain, reduce length of stay, and improve outcomes, especially in the short term.

In 2014, 385 primary partial knee arthroplasty procedures (7 patellofemoral replacement, 13 lateral, and 365 medial) were performed by the author and his 3 associates at an outpatient surgery center. Of those, 348 (95%) went home the same day while 17 (5%) required an overnight stay, with 11 for convenience related to travel distance or later operative time and 6 for medical issues. Outpatient arthroplasty is safe, it's better for us and our patients, and it is here now. In an outpatient environment the surgeon actually spends more time with the patients and family in a friendly environment. Patients feel safe and well cared for, and are highly satisfied with their arthroplasty experience.

Minimizing the risk of periprosthetic joint infection (PJI) is of interest to all surgeons performing hip and knee arthroplasty. Among the most critical factors to reducing the risk of infection include the use of pre-incisional antibiotics, appropriate skin preparation with clippers (as opposed to a razor for hair removal) and the use of an alcohol-based skin preparation. Host factors are also likewise critically important including obesity, diabetes, inflammatory arthritis, renal insufficiency, skin disorders and patients who are otherwise immune-compromised. If modifiable risk factors are identified, it would seem reasonable to delay elective surgery until these can be optimised.

One other factor to consider is the nutritional status of the patient. In a study of 501 consecutive revisions, we found that serological markers suggestive of malnutrition (albumin, transferrin or total lymphocyte count) were extremely common in the revision population. Specifically, among patients who presented for treatment of a chronic infection, 53% (67 of 126) had at least one marker for malnutrition. The prevalence of serological markers of malnutrition was lower (33%) in the group of patients undergoing revision for an aseptic reason suggesting that malnutrition was a risk factor for septic failure (p < 0.001 and OR 2.1). Interestingly, malnutrition was most common among patients of normal weight but was also common among obese patients (so-called “paradoxical” malnutrition). What was more disturbing, however, that of those patients undergoing an aseptic revision, serum markers of malnutrition were associated with a 6× risk of acute post-operative infection complicating the patient's aseptic revision.

At our center, we also have studied the use of dilute betadine at the end of the case, prior to wound closure, in an attempt to decrease the load of bacteria in the wound. In a retrospective review the prevalence of acute post-operative infection was reduced from just under 1% (18/1862) to 0.15% (1 of 688; p = 0.04). It is critical that the betadine utilised be STERILE and the dilution we use is 0.35% made by diluting 17.5 cc of 10% povidone-iodine paint in 500 cc of normal saline. Although this is a retrospective review, it does suggest a benefit and we have not seen any problems associated with its use.

The two-staged exchange for periprosthetic joint infection (PJI) has become the “gold standard” worldwide. Based on the first implementation of mixing antibiotics into bone cement by Prof. Buchholz in the 70's, the ENDO-Klinik followed a distinct one-staged exchange for PJI in over 85% of all our infected cases until today. Looking carefully at current literature and guidelines for the PJI treatment, there is no clear evidence, that a two-staged procedure has a clearly higher success rate than a one-staged approach. Although postulated in relevant articles, most recommendations, e.g. duration of antibiotics, static vs. mobile spacer, interval of spacer retention, cemented vs. uncemented implant fixation, are based on level IV to III evidence studies or expert opinions, rather than on prospective randomised or comparative data.

Potentially a cemented one-stage exchange offers certain advantages, as mainly based on need for only one operative procedure, reduced antibiotics & hospitalization time and reduced relative overall costs. In order to fulfill a one-staged approach with the above described potential success, there are obligatory pre-, peri- and post-operative details, which need to be meticulously respected. The absolute mandatory infrastructural requirement is based on the clear evidence of the bacteria in combination with a distinct patient specific plan, by an experienced microbiologist, for the topical antibiotics in the bone cement with combined systemic antibiotics.

Mandatory pre-operative diagnostic testing is based on the joint aspiration with an exact identification of the bacteria. The presence of a positive bacterial culture and respective antibiogramm is essential, to specify the antibiotics loaded to the bone cement, which allows a high topical antibiotic elution directly at the surgical site. A specific treatment plan is generated by a microbiologist. Contraindications for a one-staged exchange include: failure of > 2 previous one-staged procedures, infection spreading to the nerve-vessel bundle, unclear pre-operative bacteria specification, unavailability of appropriate antibiotics, high antibiotic resistance.

The surgical success relies not only on the complete removal of all preexisting hardware material (including cement and restrictors), furthermore an aggressive and complete debridement of any infected soft tissues and bone material is needed. Mixing antibiotics to the cement needs to fulfill the following criteria: Appropriate antibiogramm, adequate elusion characteristics, bactericidal (exception clindamycin), powder form (never use liquid AB), maximum addition of 10%/PMMA powder. Current principles of modern cementing techniques should be applied.

Post-operative systemic antibiotic administration is usually followed for only 10–14 days (exception: streptococci). We recommend an early and aggressive mobilization within the first 8 days post-operatively due to the cemented fixation an immediate mobilization under full weight bearing becomes possible in most cases.

Persistence or recurrence of infection remains the most relevant complication in the one-staged technique. As failures rates with a two-staged exchange have been described between 9% and 20% in non-resistant bacteria, the ENDO-Klinik data shows comparative results after 8–10 years of follow up, which were confirmed independently also by some other international reports and study groups.

In summary a cemented one-stage exchange offers various advantages. Mainly the need for only one operation, shorter hospitalization, reduced systemic antibiotics, lower overall cost and relatively high patient satisfaction. However a well-defined pre-operative planning regime including an experienced microbiologist is absolutely mandatory.

Deep periprosthetic infection after hip or knee arthroplasty is a disconcerting problem for patient and surgeon alike. The diagnosis of infection is sometimes obvious but frequently requires that the surgeon maintain a substantial index of suspicion for infection as the cause of pain or poor outcome after any joint arthroplasty. While surgical debridement with component retention is appropriate in a subgroup of patients with an acute periprosthetic infection most delayed and chronic infections are best treated with component resection. The pre-eminent role of two-stage exchange as the definitive treatment was established over 30 years ago. Two-stage exchange remains the gold-standard in treatment with an established track record from multiple centers and with multiple different types of infecting organisms. Some of the historical problems with two-stage exchange, such as limited mobility during the interval stage, have been mitigated with the development of effective articulating spacer techniques. Further, the emergence of drug resistant bacteria and the possibility of fungal infection make two-stage exchange the best choice for the majority of patients with deep periprosthetic joint infection in 2015.

Obtaining primary wound healing in Total Joint Arthroplasty (TJA) is essential to a good result. Wound healing problems can occur and the consequences can be devastating to the patient and to the surgeon. Determination of the host healing capacity can be useful in predicting complications. Cierney and Mader classified patients as Type A: no healing compromises and Type B: systemic or local healing compromises factors present. Local factors include traumatic arthritis with multiple previous incisions, extensive scarring, lymphedema, poor vascular perfusion, and excessive local adipose deposition. Systemic compromising factors include diabetes, rheumatic diseases, renal or liver disease, immunocompromise, steroids, smoking, and poor nutrition. In high risk situations the surgeon should encourage positive patient choices such as smoking cessation and nutritional supplementation to elevate the total lymphocyte count and total albumin.

Careful planning of incisions, particularly in patients with scarring or multiple previous operations, is productive. Around the knee the vascular viability is better in the medial flap. Thusly, use the most lateral previous incision, do minimal undermining, and handle tissue meticulously. We do all potentially complicated TKAs without tourniquet to enhance blood flow and tissue viability. The use of peri-operative anticoagulation will increase wound problems.

If wound drainage or healing problems do occur immediate action is required. Deep sepsis can be ruled out with a joint aspiration and cell count [less than 2500], differential [less than 60% polys], and negative culture and sensitivity. All hematomas should be evacuated and necrosis or dehiscence should be managed by debridement to obtain a live wound.

Persistent post-surgical pain (PPSP) remains a problem after knee replacement with some studies reporting up to 20% incidence. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical.

Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is fortunately becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help.

Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain.

Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions.

The name neurogenic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed especially by the author of this abstract. The optimum treatment I have found is lumbar sympathetic blocks. Lyrica, Gabapentin and Cymbalta may also help.

Perceived pain is the largest group. It does not matter what you tell patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Some of this pain is actually mechanical, especially in those with no benefits such as hairstylists. Perceived pain is widespread. The classic treatment on this is Dr. Ian McNabb's book “Backache”. It should be studied by all orthopaedic surgeons, who wish to understand pain complaints.

There are other issues such as good old fibromyalgia, which appears to have gone the way of the dodo. It has been replaced by something equally silly called central sensitization. The theory of central sensitization is that if one has pain somewhere or other for three months or six months or whatever, there are going to be changes in the brain and spinal cord. It then does not matter what happens to the original pain, i.e. whether or not it goes away, the pain will persist because of the changes in the brain, hence, the title of the pain in the brain syndrome.

If this theory was correct, we might as well all go home because we have all been wasting our time for the last 30 years because none of our patients would get any better. After all, all of our patients have had pain for a lot longer than three months, many of them have been involved in trauma and sometimes, compensation is at issue. The pain in the brain theory, therefore, sounds about as realistic as the flat earth society or the treatment of Galileo.

A total knee replacement (TKR) with instability is one in which the supporting soft tissues have failed or are unable to function due to component size and/or position. Instability following TKR can lead to the need for surgery in 10–22% of revision cases. Patients may complain of symptoms of giving way, difficulty climbing stairs, and the sensation that their knee may buckle under stress. Physical findings may include soft-tissue tenderness in the peripatellar and pes anserine regions, recurrent joint effusions, and joint laxity. The cause of instability after TKR should be determined pre-operatively so the problem may be corrected at the time of revision.

Instability after TKR may be due to component loosening, ligament rupture/incompetence, component malposition, mismatched flexion/extension gaps, or failure to correct ligament imbalance at the time of the index procedure. A common scenario after a cruciate-retaining TKR is that of PCL rupture, thus leading to instability in flexion and excessive posterior translation of the tibia. Other scenarios leading to TKR instability are pre-operative valgus alignment with MCL stretching, resulting in the post-operative recurrence of medial instability; or excessive resection of the posterior femoral condyles from undersizing of the femoral component, leading to laxity in flexion.

The treatment of instability after TKR generally requires component revision and balancing of the flexion and extension gaps. Isolated ligament reconstruction is not successful in the setting of a prosthetic joint due to the lack of inherent joint stability. At the time of revision, the surgeon must carefully assess the flexion gap; often posterior femoral augments must be used to upsize the femoral component and tighten the flexion space relative to the extension space; for this reason, isolated polyethylene exchange is not successful for flexion instability. For instability in the varus/valgus plane, rebalancing the knee by performing ligament releases and using a more stabilizing polyethylene insert may by sufficient.

The results of revision TKR for instability has been successful in the majority of cases, decreasing the symptoms of giving way and difficulty stairclimbing. A careful assessment of the varus/valgus stability of the prosthetic knee and the flexion/extension spaces at the time of revision TKR, along with the use of augments and more stabilised articulations, is mandatory in order to achieve good results.

Stiffness remains one of the most common, and challenging post-operative complications after TKA. The exact definition of stiffness varies, and patient expectations of post-operative motion vary as well. Pre-operative motion and diagnosis (such as post-traumatic arthritis) can influence post-operative motion, and careful patient counseling about expectations is important. Post-operative stiffness should be evaluated by ruling out infection, evaluating rehabilitation efforts, and careful physical and radiographic examination. Manipulation under anesthesia (MUA) in selected cases can be helpful. The author generally prefers to perform MUA between the 6- and 8-week mark post-operatively. Careful technique is required to minimised the risk of fracture or soft tissue injury. For more chronic stiffness, revision may be indicated, especially if an etiology is identified pre-operatively (for example, an excessively thick patellar resurfacing, an oversized femoral component, gross malrotation, etc.). CT scanning can be helpful for pre-operative evaluation and planning. During revision, thorough synovectomy and release of contractures and ligamentous balancing is performed as required. Careful attention to gap balancing, component rotation, and sizing is critical. Patients should be counseled that the results of revision for stiffness are mixed and somewhat unpredictable unless a clear etiology was found intra-operatively (for example, a grossly oversized femoral component). More frequent post-operative office visits may be helpful to guide rehabilitation progress in these challenging cases.

General Principles: All repairs should be repaired in full extension. Repairs should be immobilised in full extension for 6–12 weeks. Gradual resumption of motion in a hinged brace over an additional 6–8 weeks almost always yields flexion to at least 90 degrees. Marlex Mesh has been shown to be an excellent replacement as well as an augment for deficient soft tissue.

Acute tibial tuberosity avulsion: Open repair is best accomplished with a non-absorbable heavy Krackow suture, secured distally around a screw and washer followed by 6–8 weeks of immobilization. Augmentation with a semitendinosus graft or Marlex can provide additional support.

Acute Patella Tendon Rupture: End-to-end repair is standard, but re-rupture is not uncommon, so supplemental semitendinosus reconstruction is recommended. The tendon is harvested proximally, left attached distally and passed through a transverse hole in the inferior patella. The gracilis tendon can be harvested and sutured to semitendinosus for additional length if needed.

Acute Quadriceps Tendon Rupture: These can be repaired end-to-end with a non-absorbable heavy Krackow suture. A superficial quadriceps fascial turndown or mesh may be a useful adjunct.

Patella Fracture: Treatment depends on the status of the patellar component and the loss of active extension. If the component remains well fixed and the patient has less than a 20 degree lag. A loose component and/or > 20 degree extensor lag requires ORIF +/− component revision.

Chronic Disruptions: While standard repair techniques are possible, tissue retraction usually prevents a “tension-free” repair. In most chronic disruptions allograft extensor mechanism reconstruction is preferable. If the patella remains viable and has not retracted proximally an Achilles tendon graft is appropriate while in any patellar tendon defect, mesh repair has been shown to be effective.

For most revision total knee replacement there is associated soft tissue and bone loss. A constrained condylar implant can be useful in improving the stability of the knee after revision. Augmentation is commonly used to deal with bone loss on the femoral and tibial side of the joint. Stems are known to reduce the load at the interface of the femoral and tibial component and transfer the load into the medullary canals. There are problems with using stems in the revision setting however, which include: (1) increased cost, (2) difficulty with removal should further revision be necessary, (3) violation of the intramedullary canals if infection occurs, (4) increased operating time. For these reasons a CCK implant was developed without stems in 1998. The use of this device must be very selective and it is primarily used for severe valgus deformity in elderly patients. In a revision setting where there is good preservation of femoral and/or tibial bone but the need for increased constraint is present (e.g. unicompartmental, cruciate retaining knee) a CCK without stems can be used with good results. We retrospectively reviewed 36 primary constrained condylar knee implants without stem extensions from 1998 to 2000 in 31 patients with knees in 15 degrees valgus or greater. All patients were followed up for a minimum 10 years (range, 10 to 12 years). One patient had aseptic loosening and needed to be revised with stemmed components at 9 years post-surgery. Wear was found in two patients. One patient, with severe rheumatoid arthritis, had infection and required a two-stage re-implantation procedure. Patients who are very active or heavy body weight where stresses may be excessive at the implant bone interface should have stems utilised.

The amount of bone loss due to implant failure, loosening, or osteolysis can vary greatly and can have a major impact on reconstructive options during revision total knee arthroplasty (TKA). Massive bone loss can threaten ligamentous attachments in the vicinity of the knee and may require use of components with additional constraint to compensate for associated ligamentous instability. Classification of bone defects can be helpful in predicting the complexity of the reconstruction required and in facilitating pre-operative planning and implant selection. One very helpful classification of bone loss associated with TKA is the Anderson Orthopaedic Research Institute (AORI) Bone Defect Classification System as it provides the means to compare the location and extent of femoral and tibial bone loss encountered during revision surgery. In general, the higher grade defects (Type IIb or III) on both the femoral and tibial sides are more likely to require stemmed components, and may require the use of either structural graft or large augments to restore support for currently available modular revision components. Custom prostheses were previously utilised for massive defects of this sort, but more recently have been supplanted by revision TKA component systems with or without special metal augments or structural allograft.

Options for bone defect management are: 1) Fill with cement; 2) Fill with cement supplemented by screws or K-wires; 3) Morselised bone grafting (for smaller, especially contained cavitary defects); 4) Small segment structural bone graft; 5) Impaction grafting; 6) Large prosthetic augments (cones); 7) Massive structural allograft-prosthetic composites (APC); 8) Custom implants. Maximizing support on intact host bone is a fundamental principle to successful reconstruction and frequently requires extending fixation to the adjacent diaphysis. Pre-operative planning is facilitated by good quality radiographs, supplemented on occasion by additional imaging such as CT. Fluoroscopically controlled x-ray views may assist in diagnosing the loose implant by better revealing the interface between the implant and bone and can facilitate accurate delineation of the extent of bone deficiency present. Part of the pre-operative plan is to ensure adequate range and variety of implant choices and bone graft resources for the planned reconstruction allowing for the potential for unexpected intra-operative findings such as occult fracture through deficient periprosthetic bone.

Reconstruction of bone deficiency following removal of the failed implant is largely dictated by the location and extent of bone loss and the quality of bone that remains. While massive bone loss may compromise ligamentous attachment to bone, in the majority of reconstructions the degree of implant constraint needed for proper balancing and restoration of stability is independent of the bone defect. Thus some knees with minimal bone deficiency may require increased constraint due to the status of the soft tissues while others involving very large bone defects especially of the cavitary sort may be well managed with minimal constraint.

Outcomes of THA after Hip Arthroscopy

Hip Injections and Rapidly Progressing Joint Degeneration

Procedure Duration Wound Complications & LOS

Losing Weight Following TKA and its Influence on Outcome

Radiographic Severity of Arthritis & Patient Satisfaction in TKA

Intra-wound Vancomycin Powder Reduces Infections in TJA

Increased Non-stemmed Tibial Failures with BMI ≥ 35

Influence of Component Alignment on Outcome in Varus TKA

New TKA Designs - Do Patients Notice?

Bariatric Surgery Prior to TKA Associated with Fewer Complication

Metal Sensitivity Correlates with Pain in Patients with TJA

Blood Culture Bottles vs. Swabs for Microbial Detection in PJI

I&D Prior to 2 Stage Revision TKA Doesn't Increase Risk of Failure

Outpatient Total Joint Leads to Substantial Burden of Phone Calls

Wear and lysis of HXL Sockets: Effect of Head Size @ 10–14 Years

Surface Finish & Survivorship of Cemented Stems in THA

Patient Reported Outcome as a Tool for Appropriateness in THA

Neuraxial Anesthesia and Post-op Complications and Transfusions

We perform the direct approach using a standard radiolucent operative table with extender at the foot, and the assistance of fluoroscopy. The patient is positioned supine with the pubic symphysis aligned at the table break. The anterior superior iliac spine (ASIS) and center of the knee are marked, and a line drawn between. The incision commences proximally from two finger breadths distal and two finger breadths lateral to the ASIS, and extends distally 8–10 cm. Using fluoroscopy, the anterior aspect femoral neck is located. The incision is placed over the lateral aspect of the greater trochanter, which avoids the lateral femoral cutaneous nerve. The tensor fascia lata is identified, which has a distinctive purple hue, and dissected free from the intermuscular septum lateral to the sartorius and the rectus muscles. The deep, investing aponeurosis of the tensor fascia lata is split using a tonsil. Just below lie the lateral circumflex vessels, two veins and one artery, which must be either ligated or cauterised. A retractor is placed superior to the femoral neck over top of the superior hip capsule. A blunt, cobra-type retractor is then placed along the inferior femoral neck, deep to the rectus muscle and the rectus tendon. A sharp retractor is then used to peel the rectus off from the anterior capsule and placed over the anterior rim of the acetabulum. An anterior capsulectomy is performed. A saw blade is positioned for femoral neck resection and confirmed with fluoroscopy. After resection, acetabular retractors are placed, the socket is reamed, the cup is placed, and position confirmed with fluoroscopy. Turning to the femoral side, the surgeon palpates underneath and around the tensor, around the lateral aspect of the femur, proximal to the gluteus maximus tendon, and places a bone hook around the proximal femur. Femoral preparation and stem insertion require maneuvering the table and adjusting the patient position. The table is “jack-knifed” by lowering the foot of the table to approximately 45 degrees and placing the bed into approximately 15 degrees of Trendelenburg. The contralateral well leg is placed on the padded Mayo stand. A table-mounted femur elevator is attached to the bed, requiring a change in surgical gloves, and attached to the traction hook around the proximal femur. Gentle retraction is placed on the femur to tension the capsule. As the capsule is released the femur will begin to come up/out of the wound and into view. With increasing gentle retraction via the table-mounted hook, the femur is elevated. Simultaneously, the operative limb is externally rotated and adducted underneath the non-operative leg in a lazy “figure of 4” position by the assistant. The use of a “broach-only” stem design is preferred as direct straight reaming of the femur is difficult in most cases. Fluoroscopic images are obtained to confirm femoral implant positioning, offset, neck and leg length. A standardised rapid recovery hospitalization and rehabilitation protocol is used in all cases.

My involvement in the DEFENSE side of MoM hip litigation has allowed me the luxury of reflection and continued study of the basic and clinical science and voluminous medical and scientific literature concerning this particular wear couple. Much of what I have learned is relevant to other articular couples, and might help you in your next THR.

While useful, in vitro laboratory testing cannot wholly replicate or predict in vivo behavior of a particular wear couple. (Mother Nature always has something new to teach us!)

Although MoM implants underwent rigorous pre-market testing and evaluation by the industry and appropriate regulatory approval in both the US and EU, the process cannot assure the clinical safety or success of new designs and materials for all implant recipients.

Two year results obtained in pre-market (IDE) studies are of insufficient follow-up for accurate evaluation of the short, and certainly medium, or long-term clinical performance of new materials or designs, as demonstrated by the two year data from the Australian Joint Registry.

In certain populations, MoM bearings have performed satisfactorily (to date) in individuals for whom traditional bearings were a poor option.

Moderately to highly crosslinked UHMWPEs have functioned for at least a decade with dramatic reduction in wear volumes in THA. This wear reduction has been associated with a markedly reduced incidence of radiographic osteolysis. However, CT studies have demonstrated that osteolysis is not completely eliminated.

There, however, are still questions which include: Is cost for further improvements warranted?; Is 10 years long enough to assure that no clinically relevant osteolysis occurs, especially in younger patients?; Do we have any data demonstrating improvement in revision scenarios?; With high levels of crosslinking (requiring more radiation) some fractures have been demonstrated at the region of the locking mechanism of the liner to shell. Will this prevalence increase? These materials are softer and can cause quicker crack propagation than conventional polyethylene.; Do better locking mechanisms need to be developed to prevent fracture problems that have been demonstrated in the present generation cementless designs?; Do we need more information as to the optimal counterface choice (cobalt chrome, ceramic, oxinium)?; Can hip results be extrapolated to the knee where fatigue failure is a major problem both on the bearing surface and with the locking mechanism?; Is the oxidation we are beginning to see on the surface of retrieved liners (thought to be related to lipids from the synovium and cyclical loading) the tip of the iceberg?

I too am encouraged by the mid-term results of crosslinked polyethylene. Our own data supports it. However, we must keep in mind the questions outlined.

Generally cemented total hip arthroplasty (THA) has become an extremely successful operation with excellent long-term results. Although it always remained a popular choice for the elderly patients in many countries, recent trends show an increased use of noncemented stems in all age populations in many national registries. So far, there has been no clear age associated recommendation, when a cemented stem should be used. Described major complications including periprosthetic fractures are usually associated with age >75 years, in many registries. Uncemented stems perform better than cemented stems in recent registries; however, unrecognised intra-operative femoral fractures may be an important reason for early failure of uncemented stems. Experimental studies have indicated that intra-operative fractures do affect implant survival, it has been shown that intra-operative and direct post-operative fractures increase the relative risk of revision during the first 6 post-operative months significantly. In addition it has been clearly shown, that uncemented stems were more frequently revised due to periprosthetic fracture during the first 2 post-operative years than cemented stems.

Based on the overall femoral bone quality, especially in female patients >70 years, cemented fixation has a lower fracture risk. Based on the implant fixation type: metaphyseal vs. diaphyseal of various uncemented stems, major attention should be drawn to the intra-operative bone quality during the broaching process, especially for metaphyseal fixation stem types. Although cementless distal fixation can be achieved in thick cortices still in many patients, the incidence of associated thigh pain needs to be considered for some implant types. Furthermore small femoral canals might generate certain implant-bone size mismatch in relation to the proximal femur.

In any cemented THA, a proper cementing technique is of major importance to assure longevity of implant fixation. This also includes proper implant sizing/templating, ensuring an adequate cement mantle thickness, which might be restricted in a small diameter femur. The desired outcome is a cement interdigitation into cancellous bone for 2–3 mm and an additional mantle of 2 mm pure cement. Consequently proper planning in small diameter patients, prevents sizing problems, while in few cases special/individualised stem sizes might be considered.

Patients, and their femurs, come in all shapes, sizes, and types. Fortunately, so do cementless femoral stems! A simple approach is to separately consider A) the part inside the bone and B) the part outside the bone. The inner-cortical geometry (Dorr type), bone density, and presence of any deformity, influence selection of stem shape, length, and extent of ingrowth surface (the part inside the bone). Restoration of limb length and offset is a function of the neck angle and length (the part outside the bone). Clinical data indicates that undersizing of cementless stems increases the risk of revision for aseptic loosening while restoration of limb length and offset favorably affects patient satisfaction and function.

As an increasing number of young, active, large patients are becoming candidates for total hip replacements, there is an increasingly urgent need to identify arthroplasties that will be durable, highly functional and amenable to possible future successful revision. In an era when cemented femoral stems were the primary implant option, the concept of a surface replacement was attractive and, perhaps, appropriate. However, cementless femoral stems of many designs now provide dependable long-term fixation and excellent, near normal function in patients of all ages, sex and level of activity.

However, a number of issues related to cementless stem fixation could be further improved: Optimization of load transfer to proximal femur to minimise fracture risk and maximise bone preservation; Elimination of proximal-distal mismatch concerns, including bowed femurs; Facilitation of femoral stem insertion, especially with MIS THA exposures; Facilitation of revision with implants capable of providing durable fixation for active patients.

The potential benefits of short stem femoral THA implants include: Ease of insertion; Reproducibility of insertion; Avoidance of issues related to proximal-distal anatomic mismatch or variations in proximal femoral diaphyseal anatomy (e.g. femoral bowing); Facilitation of MIS surgical approaches, especially anterior exposures; Optimization of proximal femoral load transfer with consequent maximization of proximal bone preservation.

The purpose of this presentation is to describe the design rationale and characteristics of short (< 115 mm) uncemented primary THA femoral stem, to evaluate the clinical and radiographic results of short stems and to discuss the possible drawbacks specific to the use of short stems.

There are many types and articulating surfaces in acetabular cups. Most of the designs currently available are modular, the liner snapping into a locking mechanism of some type. These modular inserts may be polyethylene, usually highly crosslinked polyethylene, or ceramic. Metal shells used in metal-on-metal devices are usually of a monoblock design.

The elliptical monoblock design has been available for 20 years and was originally made of Titanium with a compression molded polyethylene liner. Tantalum (trabecular metal) was used as the shell material in the more recent designs and the polyethylene is actually molded directly into the tantalum framework. Monoblock acetabular components have a number of advantages. They do not allow access to the ilium because there are no holes in the socket shell with the monoblock construct. They require no locking mechanism which may increase metallic debris. No back surface liner wear can occur because all motion is eliminated at the liner/shell interface. However, because of this absence of screw holes there is an inability to visualise the floor of the acetabulum and perfect coaptation between the shell and the acetabular floor may not occur. The presence of dome gaps of greater than 1.5 mm have been noted in 5% of these components but these have not compromised implant stability and in a review of over 600 cups there has been no change in implant position.

Results with over 258 monoblock cups with a minimum of 10-year follow-up (10–15 years) have been excellent. (Poultsides, et al) The incidence of pelvic osteolysis was not seen in any patient in this series. There were 3 revisions for instability but none for mechanical failure. There were 3 femoral revisions for loosening but the cup was intact and not revised in these patients. Utilizing the Livermore measurement method polyethylene wear averages 0.08 mm per year (0.06 – 0.13 mm) and there have been no revisions for wear. Radiographic evaluation demonstrates stable bony interface in all patients. At minimum 10- year follow-up the monoblock acetabular component with compression molded polyethylene confirms the theoretical advantages of this design and results have been excellent. Moen et al have demonstrated no osteolysis in CT scans in tantalum monoblock cups at a follow up of 10.3 years.

While total hip arthroplasty (THA) is the most predictable and successful operation for relieving pain and restoring function in the arthritic hip, instability and dislocation have been identified as the most common cause (22.5%) of revision THA in the United States. Thus, minimizing the complications of impingement and dislocation are major goals for surgeons and implant designers.

A dual-mobility (DM) socket design, where there is an additional bearing with a mobile polyethylene component between the prosthetic head and the acetabular shell, was introduced in the United States in 2010. Developed by Bousquet in 1974, the DM design has been shown to be a durable solution to hip instability after THA. The smaller inside diameter head offers the potential advantage of lower wear and the larger outside diameter head offers the potential advantage of improved stability. A review of eight studies using a DM design noted only two dislocations in 1,386 (0.1%) primary THAs. Initially, indications were advocated for patients with increased instability risk as in revision THA or THA after femoral neck fracture. However, with larger diameter metal-on-metal articulations falling out of favor, DM components are increasingly being used in younger patients.

Between 2011 and 2014, the author has used DM sockets in over 400 primary THAs (age, 22–92 years). Only one dislocation was noted in this group (femoral neck fracture). One loose cup was revised. Dislocation of the smaller femoral head from the larger polyethylene head remains a theoretical risk with DM designs.

This session will be practically oriented, focusing on important surgical decisions and on technical tips to avoid complications. The panel will be polled concerning individual preferences as regards the following issues in primary total hip arthroplasty: 1. Peri-operative antibiotics/blood management/preferred anesthetics; 2. Surgical approach for primary total hip arthroplasty: indications or preferences for direct anterior, anterolateral, posterior; 3. Acetabular fixation; 4. Tips for optimizing acetabular component orientation; 5. Femoral fixation: (a) Indications for cemented and uncemented implants. (b) Role of hip resurfacing; 6. Femoral head size: Preferred head sizes in different situations; 7. Bearing surface: Present role of different bearings; 8. Tips for optimizing intra-operative hip stability; 9. Tips for optimizing leg length; 10. Post-operative venous thromboembolism prophylaxis; 11. Heterotopic bone prophylaxis; 12. Post-operative pain management; 13. Post-operative rehabilitation protocol: weight bearing, role of physical therapy; 14. Post-operative activity restrictions; and 15. Post-operative antibiotic prophylaxis for procedures.

Only a little over a decade ago the vast majority of primary total hip replacements performed in North America, and indeed globally, employed a conventional polyethylene insert, either in a modular version or in a cemented application. Beginning in the early 2000's there was an explosion in technology and options available for the bearing choice in total hip arthroplasty.

Highly crosslinked polyethylene was introduced in 1998, and within a few short years the vast majority of polyethylene inserts performed in North America were manufactured from this material. Globally there was a mixed picture with variable market penetration. Surgeons had seen historically poor results with attempts at “improving” polyethylene in the past and many were hesitant to use this new technology. Many randomised clinical trials have been performed and all have shown to a greater or lesser degree, that indeed the highly crosslinked polyethylene insert has undergone less linear and volumetric wear than its more conventional counterpart. This replicates well the hip simulator data. The challenge, however, is as we approached mid-term results, orthopaedic manufacturers began altering the polyethylene to improve wear and improve mechanical strength. Therefore while 10-year and greater data will ultimately be published, the actual polyethylene in use at that time will be a different material. Additionally, while wear rates are undoubtedly lower, we are still waiting for long-term results of actual osteolytic lesion development and the effect that highly cross-linked polyethylene will have on this clinical scenario. That being said, with over a decade of clinical experience, unquestionably highly crosslinked polyethylene has truly been a revolution in design, essentially eliminating polyethylene wear as an early failure mode.

The question still remains as to the best material for the femoral ball. Essentially two options exist – cobalt chrome and ceramic (Delta). There are theoretically advantages to ceramic heads; however they come at a cost premium: 1.) To date there have been no published reports that demonstrate any improved clinical outcomes with the use of ceramic heads. In fact, the Australian registry demonstrates that the cumulative revision rate is lowest with CoCr heads (at 10 years, 4.3% with CoCr on XLPE and 4.6% with ceramic on XLPE). 2.) Costs continue to be significantly higher for ceramic heads. A price premium of 2–4× higher cost for ceramic over CoCr heads exists in most global markets. 3.) Trunion issues. An emerging concern is corrosion at the head neck junction in THA. Ceramic heads should theoretically have a lower incidence of taper corrosion. To date this is unproven, as is the actual incidence of this as a significant clinical problem.

Recent issues related to trunionosis have created a new paradigm in choosing femoral head material in total hip arthroplasty. While many consider highly-crosslinked polyethylene (XLPE) to be the gold standard currently in acetabular liner bearing surface, the debate remains whether metal or ceramic heads are best paired with XLPE.

Wear characteristics are similar within an order of magnitude when comparing cobalt chrome femoral heads with ceramic when used in combination with XLPE. Therefore, discernable differences between the two femoral head materials with respect to outcomes would be the result of other biomechanical factors. Notably the fretting and corrosion of metal heads at the modular taper of femoral components is a serious concern and represents a significant deterrent when considering this material. The fretting corrosion that occurs with metal femoral heads has recently been well documented in multiple reports, and can be associated with adverse local tissue reactions necessitating revision hip arthroplasty. Frictional torque has recently been implicated in taper corrosion at modular junctions. In a recent simulated in vivo study, large diameter CoCr femoral heads were associated with increased frictional torque compared to smaller metal heads, supporting recent taper corrosion retrieval studies. In one recent series, a 1.1% incidence of head-neck taper corrosion with a metal head was reported and the authors recommended use of ceramic femoral heads. The notable downside of ceramic femoral heads is the implant cost and potential for fracture. However, the incidence of femoral head fracture with the newer mixed delta ceramic heads is exceptionally low and infrequent (rate 1.7 per 100,000). Furthermore, the incidence of taper corrosion is negligible with ceramic heads, making it the bearing couple of choice among many surgeons in combination with XLPE.

The anterior/Hueter approach to the hip was first described in 1883. It was then popularised in the 1940s by Judet in France using an orthopaedic positioning table which at the time was also used to treat a variety of orthopaedic injuries. In North America its use for joint replacements was limited to a few surgeons such as Kris Keggi in Connecticut using a regular surgical table as well as a select few surgeons (Joel Matta) who had trained with Emile Letournel, a student of Judet. It is fair to say that this anatomical approach to the hip was never forgotten but rather put aside as industry and clinicians focused on critical issues of implant breakage and failure as well as the larger problem of wear-related osteolysis. As we have made significant improvements in implant durability and fixation, the focus has now shifted on optimizing patient recovery and minimizing length of stay while providing the same quality of care. In these regards, the anterior approach provides a valid alternative to standard approaches to the hip due to its low risk of dislocation and minimal disruption to the musculature. In addition, the capacity of intra-operative imaging with the patient in the supine position provides assessment of component orientation as well as leg lengths. More importantly, like the advent of better instrumentation for the anterior approach, the use and optimization of the positioning table facilitates the execution of the anterior approach i.e. one assistant and no soft tissue release.

Outcome in total hip replacement is influenced by a variety of factors including patient selection, implant technology, surgical expertise and peri-operative management. As it relates to the direct anterior approach, there has been extensive marketing in order to drive patients to specific surgeons who use specific implants. Associated with this marketing, claims about superiority of this approach have been made with very little evidence to support these claims.

In a study comparing the direct anterior (DA) to the miniposterior approach, Pagnano et al showed no difference in length of stay, operative complications, IV breakthrough analgesia, stairs, maximum feet walked in hospital or percent discharged to home. The DA approach had longer operative times, higher maximum visual analog pain score and at two weeks more of the DA group required gait aids. At eight weeks the DA group had a higher Harris Hip Score but lower return to work and driving. They concluded no advantage of the DA approach. Even when comparing the DA approach to the conventional posterior approach Ranawat et al were only able to identify some benefit at 2 weeks which had disappeared by 6 weeks. Finally in a randomised prospective trial Taunton et al demonstrated very little differences between the DA and miniposterior approaches. The DA group time to ambulation without aids was slightly better in the DA group (22 vs. 28 days) and the three week SF mental scores were slightly better in the miniposterior group. They concluded little clinical or radiographic benefit was seen between the cohorts.

The evidence suggests if done well both approaches work well. The key to long term success is to get the parts in write regardless of approach.

Constrained liners are a tantalizing solution to both prevent and treat instability, as they markedly increase the force needed for a dislocation to occur. They have, however, several important negatives that the surgeon must consider before entertaining their use including: Increased stresses at the implant bone interface which can increase the risk of loosening or cause catastrophic failure in the early post-operative period; Decreased range of motion with a greater risk of impingement; and Usually require an open reduction if they dislocate or otherwise fail.

Given the limitations of constrained liners, we have looked to dual mobility articulations as an alternative to constrained liners in the past five years in our practice, including patients with abductor deficiency.

We retrospectively compared a consecutive series of revision THA that were at high risk for instability and treated with either a constrained liner or a dual mobility articulation. Indications for both groups included abductor insufficiency, revision for instability, or inadequate intra-operative stability when trialing. Forty-three hips were reviewed in the constrained group (mean follow-up 3.4 years) and thirty-six in the dual-mobility group (mean follow-up 2.4 years). The rate of failure was compared using a Fisher's exact test with a p-value of < 0.05 considered significant.

At a minimum of two years, there were 10 dislocations in the constrained group (10/43 or 23.3%) compared to 3 in the dual-mobility group (3/36 or 8.3%; p = 0.06). There were 15 repeat revisions in the constrained group (10 for instability, 4 for infection, and 1 broken locking mechanism) compared to 4 in the dual mobility group (2 mechanical failures of cemented dual mobility liners with dislocation and 2 for infection); 34.9% vs. 11.1% (p = 0.01). With repeat revision for instability as an endpoint, the failure rate was 23% for the constrained group and 5.5% for the dual mobility group (p = 0.03). Mean Harris Hip Score (HHS) improved from 45 to 76 points in the constrained liner group, and from 46 to 89 points in the dual-mobility group.

Dual mobility articulations offer anatomic sized femoral heads that greatly increase jump distance, without many of the negatives of a constrained liner. While dual mobility is associated with its own concerns and problems (including intra-prosthetic dislocation and wear) our initial results suggest that they are a viable alternative to a constrained liner, even in the most challenging situations.

In primary total hip replacements there are numerous options available for providing hip stability in difficult situations i.e. Down's syndrome, Parkinson's disease. However, in the revision situation, in general, and in revision for recurrent dislocation situations specifically, it is important to have all options available including dual mobility constrained liners in order to optimise the potential for hip stability as well as function of the arthroplasty. Even with the newer options available dislocation rates of higher than 5% have been reported in the first two years following revision surgery at institutions where high volumes of revision surgery are performed [Della Valle, Sporer, Paprosky unpublished data]. Because of the deficient abductors, other soft tissue laxity and the requirement for large diameter cups, revision cases will always have more potential for dislocation. In these situations in the lower demand patient and where, a complex acetabular reconstruction that requires time for ingrowth before optimal implant bone stability to occur isn't present, dual mobility with constraint has provided excellent success in terms of preventing dislocation and maintaining implant construct fixation to bone at intermediate term follow-up. Hence in these situations dual mobility with constraint remains the option we utilise. We are also confident in using this device in cases with instability or laxity where there is a secure well-positioned acetabular shell. We cement a dual mobility constrained liner in these situations using the technique described below.

Present indication for dual mobility constrained liners: low demand patient, abductor muscle deficiency or soft tissue laxity, large outer diameter cups, multiple operations for instability, and instability with well-fixed shells that are adequately positioned.

Technique of cementing liner into shell: score acetabular shell if no holes; score liner in spider web configuration; all one or two millimeters of cement mantle.

Hip joint preservation remains a preferred treatment option for hips with mechanically correctable pathologies prior to the development of significant secondary arthrosis. The pathologies most amenable to joint preservation are hip dysplasia and femoroacetabular impingement. These pathologies sometimes overlap. Untreated acetabular dysplasia of modest severity always leads to arthrosis if uncorrected. Acetabular dysplasia is best treated by periacetabular osteotomy, usually combined with arthrotomy for management of labral pathology and associated cam-impingement if present. Pre-operative variables associated with the best long-term outcomes include less secondary arthrosis, younger age, and concentric articular surfaces. The earlier PAO series show 20 year survivorship of 81% and 65% in Tonnis Grade 0 and 1 hips.

Femoroacetabular impingement has become progressively recognised as perhaps the most common cause of secondary arthrosis. The etiology of impingement is multifactorial and includes both genetic factors and stresses experienced by the hip prior to cessation of growth. Cam impingement can be quantified by the alpha angle as measured on plain radiographs and radial MR sequences. Cam impingement can be treated by arthroscopic or open femoral head-neck osteochondroplasty. As with hip dysplasia, prognosis following treatment is correlated with the severity of pre-operative secondary arthrosis but unfortunately impinging hips more commonly have some degree of arthrosis pre-operatively whereas dysplastic hips can become symptomatic with instability in the absence of arthrosis. The scientific basis for the treatment of pincer impingement is less strong. Unlike cam impingement and hip dysplasia, pincer impingement pathology in the absence of coxa profunda has not been correlated with arthrosis and so rim trimming with labral refixation is probably performed more often than is clinically indicated. Overall, joint preserving surgery remains the preferred treatment for hips with mechanically correctable problems prior to the development of significant secondary arthrosis.

The goal is to avoid letting femoral deformity force suboptimal implant position/fixation. Suboptimal implant position has an adverse effect on hip biomechanics and often on hip function and durability.

Classification - Practical approach to femoral deformities: categorise into 3 main groups: 1.) Very proximal, 2.) Subtrochanteric, 3.) Distal.

Management of distal deformities: Most can be ignored if there is sufficient room to place conventional femoral implant.

Management of proximal deformities: Option 1: Use implants that allow satisfactory positioning despite deformity…or… Option 2: Remove the deformity.

Management of subtrochanteric level deformities: These are the most difficult. Problems: 1.) Too proximal to ignore, 2.) Too distal to bypass. Main treatment options: 1.) Resurfacing THA, 2.) Short stem THA, 3.) Corrective osteotomy with THA.

Corrective osteotomy with THA: 1.) Perform osteotomy at level of deformity, 2.) In most cases a corrective osteotomy that creates a transverse osteotomy junction is simplest, 3.) Use an implant that provides reliable fixation in the femur (usually uncemented), 4.) Use implant that provides fixation of the proximal and distal fragments.

Majority of proximal femoral deformities managed with one-stage procedure: 1.) Excise deformity and replace with metal, 2.) Implants that allow ignoring deformity, 3.) Corrective osteotomy.

Nerve palsy occurring after elective primary total hip arthroplasty is a devastating complication because of its effect on motor strength, walking ability, potential for pain, and unexpected nature. In general, the nerve distribution involved is the peroneal branch of the sciatic nerve, and the level of involvement is usually mixed motor and sensory.

Prior publications have associated limb lengthening, dysplasia and use of the posterior approach to be associated with a higher incidence of nerve palsy. In the literature, the incidence of sciatic nerve palsy is estimated to be 0.2–1.9%.

We examined the rate of sciatic nerve palsy after THA performed by the joint replacement service at Hospital for Special Surgery between the years 1998 and 2013. Each case was matched with 2 controls that underwent THA and did not develop post-operative neuropathy. Controls were matched by surgical date having been within 7 days of their matched case's surgery date. Patient and surgical variables were reviewed using data from patient charts and the institution's total joint replacement registry. A multivariable logistic regression model was created to identify potential risk factors for neuropathy following THA while adjusting for potential confounders.

We found that, of 39,056 primary THA cases, there were 81 cases of sciatic nerve palsy, giving an incidence of 0.21%. The factors with the greatest odds ratios for nerve palsy were: history of smoking (OR=3.45); history of spinal stenosis (OR=4.45), and time of day of 1PM or later (OR=3.98). We did not find limb lengthening, dysplasia, or type of fixation to be associated with nerve palsy.

In conclusion, post-surgical neuropathy has a low incidence after primary THA, but at our institution, was associated with several factors. Spine-related comorbidities, such as spinal stenosis and lumbar spine disease, and smoking history should be closely monitored to inform the patient and surgeon for the potential increased risk of post-operative neuropathy following THA.

The transgluteal approach (TG) offers a user-friendly alternative to the heavily promoted anterior approach (DA) to total hip arthroplasty (THA). Our purpose is to illustrate the advantages and details of the technique, illustrate the surgical anatomy that differentiates TG from the “traditional posterior” technique, and point out the surprising similarities to the DA.

Unlike the traditional posterior THA, the TG preserves ITB, quadratus, and obturator externus. The conjoined tendon is released, providing direct access to the femur via the piriformis fossa. Direct acetabular access is facilitated either by using a portal through which reaming and cup impaction are performed or offset instrumentation. Intra-operative digital radiography was used in all cases. We present the clinical and radiographic outcome of 850 consecutive primary THA using the TG.

At 2–6 years follow-up, dislocation rate was 0.3%, cup abduction 35–50 degrees in 97%, 92% used a cane within 5 days, 61% reported driving within the first post-operative week. No intra-operative trochanteric fractures, nerve injuries, or wound problems were observed. Three calcar fractures were wired. Hospital stay averaged 1.5 days, no patient received a blood transfusion if their pre-operative hematocrit was normal, and 88% of patients were discharged on acetaminophen only.

The TG is a reliable and highly successful alternative to commonly used soft tissue sparing approaches in THA. It permits accelerated recovery while assuring optimal component orientation. The surgeon familiar with the traditional posterior approach can embark on a gradual learning curve that can minimise the complication rate as the surgeon learns the technique.

The Vancouver classification separates periprosthetic femur fractures after THA into three regions (A - trochanteric, B - around or just below the stem, and C - well below the stem), with fractures around or just below the stem further separated into those with a well-fixed (B1) or loose stem and good (B2) or poor (B3) bone stock. Trochanteric fractures may be associated with osteolysis and require treatment that addresses osteolysis as well as ORIF of displaced fractures. Fractures around a well-fixed stem can be treated with ORIF using cerclage or cable plating, while those around a loose stem require implant revision usually to a longer cementless tapered or distally porous coated cementless stem. Fractures around a loose stem with poor bone stock in which salvage of the proximal femur is not possible require replacement of the proximal femur with an allograft prosthetic composite or proximal femoral replacement. Fractures well below the stem can be treated with conventional plating methods.

Periprosthetic acetabular fractures are rare and usually occur in the early post-operative period or late as a result of osteolysis or trauma. These can generally be separated into those with a stable acetabular component which can be treated non-operatively, and those with an unstable component often with discontinuity or posterior column instability which require complex acetabular reconstruction utilizing plating or revision to a cup-cage.

Metal-on-metal bearing surfaces were used frequently until recently because of the potential for decreased wear and the ability to use large femoral heads which can reduce instability. However, data reported in the Australian registry over the past 5 years demonstrated an increase in failure rates compared to metal-on-polyethylene bearings. In addition, adverse local tissue reactions (ALTR) associated with pseudotumors and destruction of the soft tissue around the joint have led to revision of these implants. Unfortunately, at the present time there is no optimal management strategy that has been delineated for metal-on-metal implants because of a lack of evidence. The biologic response to metal-on-metal implants is usually local but may be systemic. The management of these patients is complex because patients may have pseudotumors and/or elevated metal ion levels and be asymptomatic. In addition, there are a number of intrinsic causes (loosening, infection, iliopsoas tendinitis) and extrinsic causes (spinal disease, trochanteric bursitis) that can be a source of pain.

There is no evidenced based approach to manage these patients and no single test should be used to determine treatment. A thorough clinical evaluation is essential and blood tests are necessary to rule out infection. Imaging studies including plain radiographs and a MARS MRI are needed to evaluate either the stability of the prosthesis and to assess for the presence of pseudotumors and soft tissue destruction around the implant. Patients with symptomatic hips and evidence of muscle involvement on MRI require revision. Finally, the clinician must always be aware of the potential for systemic effects which require early and aggressive intervention to limit the adverse response to the metal and the metal bearing.

Few will disagree that the best femoral head that a young patient can have is his or her own, native femoral head. In the active, healthy patient under age 60 with a displaced femoral neck fracture, well-done, timely ORIF presents the best chance of preserving the patient's native femoral head. Arthroplasty is generally reserved for older patients, over age 60, where attempts at ORIF in this setting have demonstrated failure rates over 40%. Recent studies have documented that approximately 80% of young patients with displaced femoral neck fractures treated with ORIF will keep their own femoral head for 10 years after injury. The variables under the surgeon's control include timing of fixation, quality of reduction, accurate implant placement and implant selection, and capsulotomy. All of these variables potentially affect outcomes. Fractures in this young age group are frequently high shear angle (vertical) Pauwels type 3 fractures, and benefit from fixed angle fixation. The author prefers anatomic reduction and stabilization with a sliding hip screw and a superiorly placed derotation screw. Careful attention to detail is important to obtain an anatomic reduction, which is the most important variable in the outcome of these challenging injuries.

Femoral neck fractures continue to be one of the most common orthopaedic injuries treated today. Owing to the increased longevity of patients, enduring activity of older patients, and widespread osteoporosis in the population, there are more femoral neck fractures treated nowadays than ever before. Over 1 million femoral neck fractures were treated in the >65 year old population, in the United States, between the years 1991–2008.

The treatment of femoral neck fractures is unique because some fractures are amenable to internal fixation, while others require endoprosthetic replacement, either with a hemiarthroplasty or total hip replacement. Traditionally, less displaced fractures are treated with internal fixation; however, in younger patients, an attempt to fix the displaced fractures may be performed, in order to avoid a joint replacement in this population. The age at which an attempt at internal fixation is performed is still controversial, and treatment must be individualised to each patient. In general, patients younger than 60 would likely have internal fixation of the femoral neck fracture, rather than joint replacement.

The paradigm for the treatment of femoral neck fractures has been changing in the last 10 years, due to advances in implant technology, surgical technique, and scientific papers that have compared the results of all three treatment options. Larger diameter femoral heads in combination with highly crosslinked polyethylene, or dual mobility head options, provide greater joint stability today than was possible in the past, thus making THA a more appealing option. Furthermore, greater use of the direct anterior approach to THA may also reduce the post-operative dislocation rate, due to preservation of the posterior capsule and short external rotators.

Therefore, the author will propose the use of arthroplasty for displaced femoral neck fractures in patients younger than 60 years of age, owing to the reliability and reproducibility of THA over ORIF. Furthermore, the advances in arthroplasty materials and surgical techniques can restore function in this group of younger patients, with greater longevity of the implant than in the past.

Properly designed ceramic-on-ceramic total hip arthroplasty has consistently shown excellent clinical outcomes without the problems associated with crosslinked polyethylene bearings such as liner dissociation, debris associated osteolysis, polyethylene fracture, clinically measurable wear, and taper-corrosion associated adverse tissue reaction when metal heads are used. The recognition of these results has been affected by the confusion with the poorer results of designs with elevated metal rims especially when coupled with the use of femoral components made of beta-titanium alloys. Our clinical experience, now at 18 years, with flush mounted liners and Ti-Al6-V4 stem and cup alloy demonstrate consistently excellent outcomes without osteolysis or ALTR. Ceramic-Ceramic THA remains the gold standard for the young active patient.

A standard is defined as something established by authority, custom, or general consent. Clearly that does not exist for ceramic on ceramic total hip replacement. A better question is: Is there any indication for a ceramic on ceramic total hip. The answer to that question should when possible be based on clinical outcome data including the value added (or not) with this more expansive technology.

Ceramic on ceramic has been popularised based on its low wear. Is this clinically relevant? Probably not, based on currently available data. Both metal on highly crosslinked polyethylene and ceramic on highly crosslinked polyethylene have very low clinically documented wear rates with excellent outcomes in multiple studies. In addition, ceramic on ceramic bearings are more sensitive to implant position. Whereas polyethylene may tolerated edge loading and impingement, ceramic bearings are less likely to do so. Dislocation remains one of if not the top reason for early revision. Even with newer ceramics, there are still less options to fine tune hip stability with ceramic on ceramic bearing surfaces. When looking at the overall, risk of revision, Bozic et al concluded that hard bearings provided no benefit in terms of risk reduction of revision. Considering their higher cost, they questioned the use of these products especially in the 65 and older age group.

Looking at the Australian Registry, the cumulative percent revision for ceramic-ceramic THA was 5.7% at 11 years compared to 5.1% for metal on crosslinked poly. The hazard ratio (adjusted for age and gender) was 1.09 in favor of ceramic on poly and the difference was highly significant (p=0.012). When one take into account the increased cost of ceramic on ceramic bearings, it is hard to make a case for ceramic on ceramic bearings.

Any use of ceramic on ceramic bearings would have to be based on the hypothesis that in the long run in young active patients they may provide an advantage. This is a hypothesis with no data to support it currently.

Venous thromboembolic events, either deep vein thromboses or pulmonary emboli, are important complications in patients undergoing knee or hip arthroplasty. The purpose of this study was to evaluate the effectiveness of a mobile compression device (ActiveCare+S.F.T.®; Medical Compression Systems, Inc., Or Akiva, Israel) with or without aspirin compared with current pharmacology protocols for venous thromboembolism prophylaxis in patients undergoing elective primary unilateral lower extremity joint arthroplasty.

A multicenter registry was established to capture the rate of symptomatic venous thromboemboli following primary lower extremity joint arthroplasty in 3,060 patients from ten sites including knee arthroplasty (1,551) or hip arthroplasty (1,509). All patients were 18 years of age or older with no known history of venous thromboembolism, coagulation disorder, or solid tumor. Use of the compression device began peri-operatively and continued for a minimum of ten days. Patients with symptoms of deep venous thrombosis or pulmonary embolism underwent duplex ultrasonography and/or spiral computed tomography. All patients were evaluated at three months post-operatively to document any evidence of deep venous thrombosis or pulmonary embolism.

Of 3,060 patients, twenty-eight (0.92%) had venous thromboembolism (20 distal deep venous thromboses, 3 proximal deep venous thromboses, and 5 pulmonary emboli). One death occurred with no autopsy performed. Symptomatic venous thromboembolic rates observed in lower extremity joint arthroplasty patients using the mobile compression device were non-inferior (not worse than) at a margin of 1.0% to rates reported for pharmacological prophylaxis, including warfarin, enoxaparin, rivaroxaban, and dabigatran except in the knee arthroplasty group where the mobile compression device fell short of rivaroxaban by 0.06%.

Use of the mobile compression device with or without aspirin for patients undergoing lower extremity joint arthroplasty provide a non-inferior risk for developing venous thromboembolism compared with current pharmacological protocols reported in the literature.

Our American Academy of Orthopaedic Surgeons (AAOS) and the American College of Chest Physicians (ACCP) have come to a consensus that the use of routine prophylaxis against venous thromboembolism (VTE) is indicated for our patients undergoing total joint arthroplasty. The new guidelines acknowledge differences in efficacy of the various agents and the variable risk of VTE among patients. Agents include warfarin, low molecular weight heparin, aspirin, oral Xa inhibitors, and direct thrombin inhibitors. The use of pneumatic compression devices have been found to be effective in decreasing risk of deep vein thrombosis (DVT) as a stand-alone strategy after total knee arthroplasty (TKA) and is given a level 1C recommendation by ACCP while the data is less strong for use following total hip arthroplasty (THA). Mechanical devices are not associated with an increased bleeding risk, and address the concerns of some surgeons with regard to post-operative bleeding. The availability of mobile compression devices has expanded the indications for use as a result of portability.

While the use of mobile pump technology in DVT prophylaxis adds to the armamentarium of tools available for use in VTE risk mitigation, it does not eliminate the need for pharmacologic prophylaxis. While all arthroplasty patients are at elevated risk of VTE, the highest risk is associated with those having a prior history of DVT or pulmonary embolism (PE), having had prior surgery within the preceding three months, or requiring prolonged immobilization post-operatively for any reason. In these patients, thromboprophylaxis with any of a number of agents will play a valuable role in VTE risk reduction. Additionally, not all patients tolerate the use of the pump device. Those individuals with chronic peripheral arterial disease or arterial ulcers in the legs are also poor candidates for mechanical compression strategies which may exacerbate existing vascular compromise and perfusion of the limb. Assessment of the medical comorbidities of the patient may also stratify them to higher risk where the demonstrated benefits of pharmacologic prophylaxis outweigh the considerations of bleeding associated with their use (such as in the morbidly obese/high BMI patients).

Mobile pump technology is a valuable adjunct to our VTE reduction strategies, but do not eliminate the need for pharmacologic agents. The judicious selection of DVT prophylaxis strategies based on the totality of the constellation of orthopaedic and medical factors unique to each patient allows us to make clinical decisions tailored to their needs, their risk of VTE, and their reliability in functioning as an active partner in their own post-operative care.

This session will present a series of challenging and complex primary and revision cases to a panel of internationally respected hip arthroplasty experts. The primary cases will include challenges such as hip dysplasia, altered bony anatomy and fixation challenges. In the revision hip arthroplasty scenarios issues such as bone stock loss, leg length discrepancy, instability and infection will be discussed. This will be an interactive case based session that at its conclusion should leave the attendee with a more thorough approach to these challenging issues.

Corrosion at metal/metal modular interfaces in total hip arthroplasty was first described in the early 1990's, and the susceptibility of modular tapers to mechanically assisted crevice corrosion (MACC), a combination of fretting and crevice corrosion, was subsequently introduced. Since that time, there have been numerous reports of corrosion at this taper interface, documented primarily in retrieval studies or in rare cases of catastrophic failure.

We have reported that fretting corrosion at the modular taper may produce soluble and particulate debris that can migrate locally or systemically, and more recently reported that this process can cause an adverse local tissue reaction. Based on the type of tissue reaction and the presence of elevated serum metal ion levels, this process appears quite similar to adverse local tissue reactions secondary to metal-on-metal bearing surfaces. While modularity in THR has demonstrable clinical benefits, modular junctions increase the risk of corrosion and the types of adverse soft tissue reactions seen in patients with accelerated metal release from metal-on-metal bearing THRs.

Revision of the failed femoral component can be challenging. Multiple reconstructive options are available and the procedure is technically difficult and thus meticulous pre-operative planning is required. The Paprosky Femoral Classification is useful as it helps the surgeon determine what bone stock is available for fixation and hence, which type of femoral reconstruction is most appropriate.

Type 1 Defect: This is essentially a normal femur and reconstruction can proceed as the surgeon would with a primary femur.

Type 2 Defect: The metaphysis is damaged but still supportive and hence a stem that gains primary fixation in the metaphysis can be used.

Type 3 Defect: The metaphysis is damaged and non-supportive and hence a stem that gains primary fixation in the diaphysis is required. Broken down into types “A” and “B” based on the amount of intact isthmus available for distal fixation.

Type 3A Defect: >4 cm of intact femoral isthmus is present. Can be managed with a fully porous coated stem, so long as the diameter is <18 mm and torsional remodeling is not present.

Type 3B Defect: There is < 4 cm of intact femoral isthmus and based on lower rates of osseointegration if a fully porous coated stem is used, a modular titanium tapered stem is recommended.

Type 4 Defect: The most challenging to manage as there is no isthmus available for distal fixation. Can be managed with proximal femoral replacement if uncontained and impaction grafting if contained. We have also successfully used modular titanium tapered stems that appear to gain “3-point fixation” in this type of defect.

I use monolithic, cylindrical, fully porous coated femoral components for many femoral revisions. Our institutional database holds information on 1000 femoral revisions using extensively porous-coated stems. To date, 27 stems have been re-revised (14 for loosening, 4 for infection, 7 for stem fracture, 2 at time of periprosthetic femoral fracture). Using femoral re-revision for any reason as an end point, the survivorship is 99 ± 0.8% (95% confidence interval) at 2 years, 97 ± 1.3% at 5 years, 95.6 ± 1.8% at 10 years, and 94.5 ± 2.2% at 15 years.

Similar to Moreland and Paprosky, we have identified pre-revision bone stock as a factor affecting femoral fixation. Among the 777 femoral revisions graded for femoral bone loss, 59% of the femurs were graded as having no cortical damage before the revision, 29% had cortical damage extending no more than 10 cm below the lesser trochanter, and 12% had cortical damage that extended more than 10 cm below the lesser trochanter. When the cortical damage involved bone more than 10 cm below the lesser trochanter, the survivorship, using femoral re-revision for any reason or definite radiographic loosening as an end point, was reduced significantly, as compared with femoral revisions with less cortical damage.

In addition to patients with Paprosky type 3B and 4 femoral defects there are rare patients with femoral canals smaller than 13.5 mm or larger than 26 mm that are not well suited to this technique. Eight and 10” stems 13.5 or smaller should be used with caution if there is no proximal bone support for fear of breaking. Patients with canals larger than 18 mm may be better suited for a titanium tapered stem with flutes. While a monolithic stem is slightly more difficult for a surgeon to insert than a modular femoral stem there is little worry about taper junction failure.

The femoral diaphysis presents the best opportunity for fixation during revision THA. Both fully coated cylindrical and modular fluted tapered titanium stems have demonstrated excellent results. Cylindrical stems have demonstrated concerning rates of failure when used in larger, osteopenic canals or in canals with post-isthmal divergent morphologies. Modular stems offer the advantage of separating distal fixation needs from proximal version, leg length, and offset needs via a modular junction. Although early designs demonstrated some breakages at the taper or through thin proximal bodies, newer generation implants have not demonstrated such mechanical concerns. Additionally, the modular junctions do not appear to be having any problems with corrosion. Mid- to long-term data with various designs now support the safety and efficacy of these constructs that can handle a wide variety of challenges during femoral revision. Careful attention to detail is necessary to minimise the risk of subsidence and intra-operative fracture or femoral perforation.

With cementless porous-coated acetabular replacements, extensive bone loss can occur without effecting implant stability. As a result, the surgeon is frequently faced with re-operating on a well-fixed cementless acetabular component with osteolysis and must decide whether or not to remove a well-fixed porous coated socket. A classification system and treatment algorithm has been developed to aid in management decisions regarding re-operation for polyethylene wear and pelvic osteolysis.

Cases are classified into one of 3 possible categories depending on the radiographic stability of the porous coated shell and the ability to replace the polyethylene liner. Type I case; stable porous coated shell, liner replaceable; Type II case; socket stable, liner not replaceable;

Type III case; socket loose, not osseointegrated.

Treatment Algorithms - Retain well-fixed shell in Type I cases and replace the liner. Debride accessible lytic lesions and graft with allograft chips. Remove the well-fixed shell in Type II case. Assess defect once the shell is removed. Reconstruction based on the bony defect present. The vast majority can be revised with a larger porous coated socket. Remove loose socket in Type III cases. Assess defect and reconstruct based on the defect. There is a greater need for more extensive grafting and the use of reconstruction rings with Type III cases.

This treatment algorithm has helped the authors successfully evaluate and treat a large series of patients with polyethylene wear and pelvic osteolysis in association with porous coated acetabular components. The stability of the acetabular component and appropriate knowledge of the implant are important factors that impact surgical management.

Several methods of treatment are available in the revision of loose acetabular components associated with significant bone loss. Jumbo cups are the preferred treatment for large acetabular defects with segmental and cavitary defects. By definition, a jumbo cup has a minimum diameter of 62 mm in women, 66 mm in men, or is greater than 10 mm larger than the normal contralateral acetabulum. They are easier to use and less expensive than cages, bulk supporting allografts, or custom cups. Proper technique is for bone to be moved, not removed. The acetabulum is reamed larger to gain more host-bone surface area. The acetabulum should then accommodate the large shell and maximise the shell host-bone contact for long-term biological fixation. The preferred shell is one with high porosity to maximise the potential area for bone ingrowth when less bone contact is present. At least 50% host-bone to shell contact is ideal but not mandatory. The larger surface area of a jumbo cup provides more opportunity for bone ingrowth. Therefore having an initially stable cup is more important than the amount of host-bone contact. Jumbo cups are only contraindicated in acetabulae that lack the superior lateral acetabulum and the posterior column. In that situation, fortunately uncommon, a cup/ cage reconstruction is used.

We reported a retrospective review of 690 acetabular revisions performed from 1986–2005. Jumbo cups were used in 196 (28%) of all the acetabular revisions and greater than 95% of the cases with large defects. This is the largest series or revisions with jumbo cups reported. Significant bony deficiencies were present; 68% were Paprosky type II and 25% were Paprosky type III. The average follow-up for the jumbo cups was ten years. Five revisions and two resection arthroplasties were performed for failure. The probability of survival of the jumbo cups was 98% at four years and 96% at 16 years.

Porous jumbo cup acetabular revision with supplemental screw fixation provides good to excellent intermediate- and long-term outcomes.

The custom triflange acetabular component has been advocated for severe acetabular defects and pelvic discontinuity, cases in which a porous-coated hemisphere will not work. These are AAOS type III or IV defects, or alternatively classified as Paprosky 3B. Many have a pelvic discontinuity. A pre-operative CT of the pelvis is sent to the manufacturer who generates a one-to-one scale 3D model of the hemipelvis. The surgeon can review either a pdf file or an actual model. If the visualised defect cannot be treated with traditional methods then a triflanged component is created. The components have backside porous and hydroxyapatite coating. Initial rigid fixation is obtained with screw fixation to the ilium and ischium. Subsequent bone ingrowth can provide long term fixation. The goal is to span the acetabular defect and obtain fixation to the ilium and ischium with a third arm which rests on the pubis. Christie first reported on 67 hips (half with a discontinuity) with a mean follow-up of 53 months. No components were removed. There was an 8% reoperation for dislocation, 6% partial sciatic nerve palsy. 46% walked without support. Dennis reported 26 hips with a mean 54 month follow-up. Eighty-eight percent were considered successful. One implant was removed and left with a resection arthroplasty and 2 others had loose components but refused reoperation. Loosening of the ischial screws was a sign of failure in the three cases. Taunton reported 57 cases with a pelvic discontinuity treated with a triflange at mean follow-up of 65 months. Eighty-one percent had a stable component and a healed pelvic discontinuity. These authors also compared a custom triflange to a trabecular metal cup-cage construct finding similar implant costs of $12,500 and $11,250, respectively. All advocates of custom triflange acetabular components believe the results are similar or superior to other options in these very challenging cases at early follow-up. The primary disadvantage of the technique is the pre-operative time required to manufacture the device – typically 4–8 weeks.

Acetabular cages are necessary when an uncemented or cemented cup cannot be stabilised at the correct anatomic level. Impaction grafting with mesh for containment of bone graft is an alternative for some cases in centers that specialise in this technique.

At our center we use three types of cage constructs –

(A) Conventional cage ± structural or morsellised bone grafting. This construct is used where there is no significant bleeding host bone. This construct is susceptible to cage fatigue and fracture. This reconstruction is used in young patients where restoration of bone stock is important.

(B) Conventional cage in combination with a porous augment where contact with bleeding host bone can be with the ilium and then by the use of cement that construct can be unified. The augment provides contact with bleeding host bone and if and when ingrowth occurs, the stress is taken off the cage.

(C) Cup Cage Construct – in this construct there must be enough bleeding host bone to stabilise the ultra-porous cup which functions like a structural allograft supporting and eventually taking the stress off the cage. This construct is ideal for pelvic discontinuity with the ultra-porous cup, i.e., bridging and to some degree distracting the discontinuity. If, however, the ultra-porous cup cannot be stabilised against some bleeding host bone, then a conventional stand-alone cage must be used.

In our center the cup cage reconstruction is our most common technique where a cage is used, especially if there is a pelvic discontinuity.

Infected total hip arthroplasty (THA) is catastrophic, but it is treatable with a high degree of success. Two-stage revision with an antibiotic-loaded cement spacer is the most widely accepted method of treatment, and considered by some to be the best method; however, single-stage treatment currently is used widely, and is gaining acceptance. Although antibiotic-loaded cement is considered to be important for antibiotic delivery after surgery, cementless revision is equally successful with one- or two-stage procedures.

Delivery of antibiotics with depot methods, such as cement or bone graft impregnated with antibiotics, is considered to be very effective, but the antibiotic levels rapidly deteriorate after the first three days, leaving the cement itself vulnerable to colonization by resistant organisms. Nephrotoxicity is not common, but it does occur, and necessitates removal of the cement. This can be catastrophic if the implants are fixed with antibiotic-impregnated cement.

Success rates of THA revision for infection can be as high as 98%, but this rate is dependent on the organism. Failure rates of 20% are the norm for resistant organisms such as methicillin-resistant Staphylococcus aureus. The cost of this failure rate is huge. Failure probably is due to the low concentration of antibiotics in the operative site. Antibiotic infusion into the operative site achieves concentrations that are hundreds of times higher than can be achieved with any other technique, and has the additional advantage of being able to be discontinued in the case of renal or otic damage. Limited personal experience suggests that the failure rate of revision total hip with resistant organisms is significantly lower with intra-articular delivery than with other currently available methods.

Revision hip approaches can be divided into posterior, anterior, transgluteal, and transtrochanteric. The approach chosen is dictated by what needs to be exposed and the approaches with which the surgeon is comfortable.

The posterior approach remains posterior to the gluteus medius and protects the hip abductors. The disadvantage of a posterior approach is post-operative dislocation.

The direct anterior approach is currently enjoying popularity as a primary technique. Surgeons experienced in the primary technique are applying it to revision surgery. The anterior approaches also protect the hip abductors. The disadvantage is poor access to the posterior acetabular column and mobilization of the femur to gain access to the femoral diaphysis.

Transgluteal approaches split the gluteus medius typically keeping the anterior portion of the medius intact with the vastus lateralis. Proximal exposure is limited by the superior gluteal nerve, which is 4 cm above the tip of the trochanter. The disadvantage of the transgluteal approach is difficult access to the posterior acetabular column and occasional abductor weakness.

The advantage of both the anterior and transgluteal approaches is a lower dislocation rate.

All three approaches are acceptable for revisions that only require acetabular rim and proximal femoral exposure. More extensive exposure requires modifications to these approaches or the use of a transtrochanteric approach.

Transtrochanteric approaches are defined by the length of the osteotomy (conventional or extended) and if the vastus lateralis remains attached to the trochanteric fragment (slide).

Distally extended osteotomies improve access to the femur.

Osteotomies without a distal attachment to the lateralis can be retracted proximally thus improving exposure of the ilium.

The indications for cementless acetabular fixation have been broadened because our data supports the use of trabecular metal cups even when there's limited bleeding host bone contact. Trabecular metal augments have allowed us to use cementless cups when there is segmental loss of bone.

The acetabular bed is prepared. If there is less than 2 mm medial bone stock, then morsellised allograft is impacted by reverse reaming. When reaming is complete and less than 50% bleeding host bone is available for cup stabilization, then a trabecular metal (TM) cup is indicated.

Trabecular augments are used if the trabecular cup trial is not stable, or if it is uncovered by 40% or more. The conventional augments come in different sizes to accommodate the diameter of the cup and the size of the defect. Larger defects are addressed with anterior and posterior column augments, and superior defects with figure of seven augments. Augments are fixed with at least two screws. The interface between the cup and the augments should be stable, but some surgeons place a very thin layer of cement between the augment and cup so micromotion does not occur while ingrowth is occurring.

We have used trabecular metal augments in 46 acetabular revisions in conjunction with a TM cup. Thirty-four cases have at least 2 years follow-up with an average of 64.5 months. There has been 4 cup loosenings with 3 re-revisions.

We still feel there is a role for structurally acceptable allografts in young patients who are likely going to require another revision. Our long term results have demonstrated that bone stock is restored facilitating the re-revision.

When is revision surgery contraindicated in the face of a failed total hip? Surgically indicated can be interpreted as a situation where the patient will benefit from a specific intervention, with sufficient likelihood, to warrant the risks of intervention. Contraindication connotes the opposite; the risks, or likelihood of the intervention's failure to achieve the desired results outweigh the expected extent and likelihood of benefit. Contraindicated actually represents the end point of a complex decision making process which must be carried out by the practitioner in conjunction with the patient and may require the full range of the surgeons analytical, technical and communication skills. Most commonly the term means that the surgeon's thinking has led to a belief that the patient will be better off without further surgery.

Deciding to forego another revision usually means leaving the patient with a resection arthroplasty. Relative indications for resection, or even avoiding revision of a failed arthroplasty, are most commonly biological. In a healthy host, with a sterile but anatomically deficient bed with adequate soft tissue coverage, mechanical reconstruction capabilities and massive bulk allograft may allow reconstruction of almost any amount of tissue loss. Severe osteomyelitis or soft tissue infection, unmanageable for reasons, including but not limited to: chronic immune-suppression, mixed or resistant organisms or a life threatening sensitivity to antibiotics which may be required to treat the sepsis. More subjective factors, such as adequacy of soft tissue and bone stock, comorbid medical conditions or a patient's desire to avoid additional surgery as well as costs must be considered. This decision may include dozens of other considerations, some of which may be considered pre-operatively and some which may only arise intra-operatively.

Total hip arthroplasty is among the most successful interventions in all of medicine and has recently been termed “The Operation of the Century”. Charnley originally stated that “Objectives must be reasonable. Neither surgeons nor engineers will ever make an artificial hip joint that will last 30 years and at some time in this period enable the patient to play football.” and he defined the appropriate patient as generally being over 65 years of age. Hip rating scales developed during this time were consistent with this approach and only required relief of pain and return to normal activities of daily living to achieve a perfect score. Since this time, however, hip arthroplasty has been applied to high numbers of younger, more active individuals and patient expectations have increased. One recent study showed that in spite of a good hip score, only 43% of patients had all of their expectations completely fulfilled following THA.

The current generation metal-metal hip surface replacement arthroplasty (SRA) has been suggested as an alternative to standard THA which may offer advantages to patients including retention of more native bone, less stress shielding, less thigh pain due to absence of a stem, less limb length discrepancy, and a higher activity level. A recent technology review by the AAOS determined that currently available literature was inadequate to verify any of these suggested potential benefits. The potential complications associated with SRA have been well documented recently. The indications are narrower, the implant is more expensive, the technique is more demanding and less forgiving, and the results are both highly product and surgeon specific. Unless a clinical advantage in the level of function of SRA over THA can be demonstrated, continued enthusiasm for this technique is hard to justify.

To generate data on the level of function of younger more active arthroplasty patients, a national multicenter survey was conducted by an independent university medical interviewing center with a long track record of conducting state and federal medical surveys. All patients were under 60, high demand (pre-morbid UCLA score > 6) and had received a cementless stem with an advanced bearing surface or an SRA at one of five major total joint centers throughout the country. The detailed questionnaire quantified symptoms and function related to employment, recreation, and sexual function. Patients with SRA had a higher incidence of noises emanating from the hip than other bearing surfaces although this was transient and asymptomatic. SRA patients were much more likely to have less thigh pain than THA, less likely to limp, less likely to perceive a limb length difference, more likely to run for exercise, and more likely to run longer distances. In another study of over 400 THA and SRA patients at two major academic centers, patients completed pain drawings that revealed an equivalent incidence of groin pain between THA and SRA, but an incidence of thigh pain in THA that was three times higher than in SRA in young active patients.

While some or most of the observed advantages of SRA over THA may be attributable to some degree of selection bias, the inescapable conclusion is that SRA patients are demonstrating clinical advantages that warrants continued utilization and investigation of this procedure.

Acetabular component malalignment remains the single greatest root cause for revision THA with malposition of at least ½ of all acetabular components placed using conventional methods. The use of local anatomical landmarks has repeatedly proven to be unreliable due to individual variation of these structures. As a result, the use of such landmarks without knowledge of their three-dimensional orientation may actually be a major cause of component malpositioning. Traditional navigation and robotics can potentially lead to improved component placement but these technologies have not gained widespread use due to the increase in time of use, complexity, and cost of these systems. The alternative of placing the cup in the supine position, even with the use of arthroscopy, has been proven to have an incidence of inaccuracy equal or greater than that in the lateral position.

A smart mechanical instrument system was developed to quickly and easily achieve accurate cup alignment (HipXpert System, Surgical Planning Associates, Boston, MA). The system is based on a low dose, low cost CT study and a customised patient-specific surgery plan. The laterally-based system docks on a patient-specific basis with 3 legs: one through the incision behind the posterior rim, one percutaneously on the lateral side of the ASIS, and a third percutaneously on the surface of the ilium. A direction indicator on the top of the instrument points in the desired cup orientation. The anteriorly-based system also docks on a patient-specific basis with one leg on the anterior ischium and one leg on each ASIS, either to skin or to bone.

The lateral system has been proven to be robust, with repeated studies showing accurate cup placement in 100% of cases and an independent study showing accurate cup placement in 98% of cases for both anteversion and inclination. This compares to a recent study of robotic methods with 88% for inclination and 84% for anteversion.

Smart mechanical navigation of cup placement offers the optimum combination of accuracy, speed, and simplicity for solving the ubiquitous problem of acetabular component malorientation.

Acetabular component orientation can directly influence dislocation rates, polyethylene wear, and revision rates. Precise placement has been found to occur in only 38–47% after total hip arthroplasty (THA). The recent introduction of digital radiography (DR) has enabled a paradigm shift in intra-operative imaging technology. Rather than deal with the cumbersome process of chemical image processing we can now acquire a high quality digital image in a matter of seconds. The functionality approaches that of fluoroscopy, or even a C-arm, however, a digital system can operate with lower radiation, higher resolution, and perhaps most importantly a larger field of view. These features make it very suitable for use during surgery. The purpose of this presentation is to illustrate the current intra-operative technique and share the overwhelmingly positive experience gathered over the past five years.

Traditional THA employs use of post-operative radiography for “outcome assessment.” This unfortunately does not allow the surgeon to evaluate the relevant parameters and make necessary adjustments without returning to the operating room. Digital imaging, however, permits intra-operative guidance and “outcome control.” It provides an immediate and complete preview of what the post-operative film will show. There is now an opportunity to optimise component orientation, sizing, apposition, screw position, limb length, and offset, before leaving the operating room. This can be done with minimal intrusion on normal workflow, adding only a few minutes of operating time.

Abductor deficiency after THA can result from proximal femoral bone loss, trochanteric avulsion, muscle destruction associated with infection, pseudotumor, ALTR to metal debris, or other causes. Whiteside has described a transfer of the tensor muscle and anterior gluteus maximus to the greater trochanter for treatment of absent abductors after THA. Transposition of the tensor muscle requires raising an anterior soft tissue flap to the lever of the interval between the tensor muscle and sartorius, which is the same interval used in an anterior approach to the hip. The muscle is transected distally and transposed posteriorly to attach to the proximal femur. This can result in soft tissue redundancy between the posterior tensor muscle and anterior gluteus maximus. This interval is separated and the anterior gluteus maximis also attached to the proximal femur.

Relatively large unconstrained (36 mm heads) were not found to be effective in controlling dislocation in patients with abductor deficiency. In our practice, 11 patients with abductor deficiency were treated with Whiteside's tensor muscle transfer and an unconstrained large diameter femoral head. The mean pre-operative abductor strength was 2.2 and improved to 3.2 post-operatively. One patient sustained a dislocation four weeks after surgery which was treated with open reduction. All of the other hips have remained stable. The combination of a large head and tensor muscle transposition may be a viable alternative to use of a fully constrained component in patients with deficient abductors after THA.

Fixation of cemented femoral stems is reproducible and provides excellent early recovery of hip function in patients 60–80 years old. The durability of fixation has been evaluated up to 20 years with 90% survivorship. The mode of failure of fixation of cemented total hip arthroplasty is multi-factorial; however, good cementing techniques and reduction of polyethylene wear have been shown to reduce its incidence. The importance of surface roughness for durability of fixation is controversial. This presentation will describe my personal experience with the cemented femoral stem over 30 years with 3 designs and surface roughness (RA) ranging from 30–150 microinches.

The author's experience is with a specific type of femoral stem and modular neck both fabricated from Ti alloy. Fracture of this Ti-Ti modular neck is associated with heavy weight, heavy activity, long modular necks and corrosion at the junction of the neck to the stem. Instruments have been designed that can remove the distal fragment of the fractured modular neck in most cases.

After the neck is removed, the clinician is faced with the decision to remove the stem or to place another modular neck. At present MicroPort (formerly Wright Medical Technology) the company whose modular neck forms the data for this presentation, suggests that the female part of the taper (that is the part at the top of the stem) should not be reused if a modular neck (fractured or intact) has been removed. Thus the recommendation from the company is that the stem be removed. This recommendation is true across all modular neck – femoral stem combinations particularly for those that have been recalled by the manufacturer.

There is no question that the female taper is changed by having had the modular neck implanted. In most cases of fracture there is severe corrosion at the junction of the neck to stem. Thus, reuse of the taper could have problems and it is understandable that the company does not sanction its reuse. On the other hand, removal of a well-fixed ingrown stem is not without morbidity. In several cases, with patient informed consent, I have left the stem and implanted a new modular neck (either CoCr or Ti alloy) in the damaged taper. We are following these patients closely and it is too soon to make recommendations as to the wisdom of this practice.

My strong recommendation is to remove the stem and place a new one.

Ceramic bearing complications are a rare, but can be catastrophic, complication following total hip arthroplasty (THA). Particulate debris from these failed bearings can cause damage the underlying femoral and acetabular components and/or cause further damage to future hip implants. Failure to recognise and appropriately manage these events can lead to significant morbidity.

Ceramic component fractures should be treated expeditiously. Delays in diagnosis and treatment can result in destructive damage of the underlying hip prosthesis caused by sharp, abrasive wear of ceramic particles. Patients with ceramic fractures present with sudden onset of pain and dysfunction. Often, the patient will report a noisy hip articulation. Radiographs can range from subtle densities surrounding the hip implant to complete disintegration and loss of sphericity of the femoral head or acetabular liner. As with any other causes of failed joint arthroplasty, a systematic evaluation and workup for failure is mandatory prior to revision surgery.

Revision options for failed ceramic components depend on component fixation, position, and type. In order to retain existing implants, the components must be well fixed, appropriately positioned, and have tapers that are undamaged and can accept current femoral heads. If these conditions are not met, then revision of components should be performed to optimise outcomes. Additionally, an extensile exposure is necessary in order to perform a complete synovectomy in order to remove as much of the ceramic particulate debris. Finally, the question of optimal bearing choice following component revision remains an area of debate. Newer, alumina composite ceramic ball heads are harder and more scratch resistant that metal ball heads and therefore preferred in my personal practice.

In summary, ceramic bearing complications are rare but catastrophic events. A systematic approach to evaluation and management is necessary to ensure a safe return.

A trochanteric osteotomy offers extensile exposure of the hip on both the acetabular and femoral sides. The classical trochanteric osteotomy which is transverse and involves a release of the vastus lateralis muscles is complicated by a significant incidence of trochanteric nonunion and more importantly, trochanteric migration. The trochanteric slide was designed to avoid trochanteric migration by keeping the trochanteric fragment in continuity with the abductors and the vastus lateralis. Even if there was a trochanteric nonunion, a trochanteric migration was prevented by continuity of muscles enclosing the greater trochanter in a sling of muscle.

When we first started doing the trochanteric slide, we used the technique originally described which involved starting with the posterior approach to take down the external rotators and the posterior capsule, and then proceeding with the trochanteric osteotomy. We found that our incidence of posterior dislocation increased to 15%. We therefore decided that we would attempt to do this operation but try to preserve the external rotators and the posterior capsule so they remained in situ attached to the main body of the femur, so that the trochanteric osteotomy was carried out just anterior to these muscles and posterior capsule. As a result of this our dislocation rate went from 15% to 3%.

This exposure provides an extensile exposure of the pelvis and femur. If femoral component removal is anticipated to be difficult, then we use exactly the same approach but we extend the trochanteric fragment down as in an extended trochanteric osteotomy.

Over a four year period of time, 142 consecutive hip revisions were performed with the use of an extended proximal femoral osteotomy. Twenty patients had insufficient follow-up or were followed elsewhere and were excluded from the review. The remaining 122 revisions included 83 women and 39 men. Average age at time of revision was 63.8 (26–84) years. Indications for revision were aseptic loosening (114), component failure (4), recurrent dislocation (2), femoral fracture (1) and second stage re-implantation for infection (1).

The extended proximal femoral osteotomy gave easy access to the distal bone-cement or bone prosthesis interface in all cases. It allowed neutral reaming of the femoral canal and implantation of the revision component in proper alignment. Varus remodeling of the proximal femur secondary to loosening was handled with relative ease implementing the osteotomy. Average time from the beginning of the osteotomy procedure to the complete removal of prosthesis and cement was 35 minutes. There were no non-unions of the osteotomised fragments at an average post-operative follow-up of 2.6 years with no cases of proximal migration of the greater trochanteric fragment greater than 2 mm, there was evidence of radiographic union of the osteotomy site in all cases by 3 months. Stem fixation with bone ingrowth was noted in 112 (92%) of 122 hips, stable fibrous fixation was seen in 9 (7%) and 1 stem was unstable and was subsequently revised. However, there was an incidence of 7% perforation rate of the femoral canal distal to the osteotomy site during cement removal. This was most prevalent where there was greater than 2 cm of cement plug present which was well bonded. When OSCAR was used instead of hand tools or power reamers, there were no perforations in 51 cases. There has been no failure of fixation with fully porous coated stems inserted in the canals where OSCAR had removed cement. Also, the use of OSCAR has allowed us to shorten the osteotomy, thus allowing a longer, intact isthmus to remain so that shorter stems can be used. We highly recommend the use of OSCAR in conjunction with the extended osteotomy for removal of well-fixed distal cement beyond the extended osteotomy site.

The technique for removal of bone ingrown extensively coated devices involves cutting the stem below the metaphyseal portion of the stem, followed by removal of the proximal stem and trephine removal of the cylindrical distal portion of the stem. This can be done with or without an extended trochanteric osteotomy (ETO). When the proximal portion of the stem is not bone ingrown (extensive proximal osteolysis, or the stem is broken) or the metaphyseal bone is easily accessed (there is no collar) the stem can be cut through a bone window. In all other cases an ETO at the level where the stem becomes a cylinder is required to disrupt the metaphyseal bone prosthesis interface, cut the stem and extract the proximal portion of the stem.

Glassman described the techniques for removal of cementless stems in 1992. Forty-two loose stems were easily removed, 11 fibrous stable implants were removed with thin osteotomes, and 11 bone ingrown, canal filling, extensively coated stems were removed with trephines. In no cases was reconstruction precluded by stem removal. The critical tools required included manufacturer specific removal tools, high speed burs, thin osteotomes, universal extraction device for connection to the neck, and multiple trephines.

More recently, Kancherla reported the use of trephines to remove 36 porous coated stems. Eighty-six percent of cases were bone ingrown after removal, however, complications included an extruded trephine causing a femoral fracture and two periprosthetic fractures thought to be secondary to trephine induced osteonecrosis. The authors recommend bypassing the most distally trephined bone by a minimum of 4 cm.

Trephines are very helpful for removing distally fixed stems. Multiple trephines need to be irrigated and changed frequently to avoid dull cutting teeth which can lead to bone necrosis.

In revision surgery of a neglected loose cemented stem, especially if long-standing infection is present, the bone may become extremely thin and fragile. A fracture during implant removal, therefore, occurs readily and the bone may simply disintegrate so that it cannot be reconstructed to produce intrinsic stability. In such cases, rather than try to put together a house of cards, the bail and nail technique may be used.

I first described this in 1992. A large bore intramedullary nail is inserted into what is left of the femur and the bone fragments proximally or cerclage wires are around the nail. The patient is left with a Girdlestone. Most patients cannot weight-bear on a Girdlestone for about two months. After that time, they are encouraged to do so as load bearing speeds healing and bone regeneration.

Generally, within six to nine months, the femur is reconstituted and a revision can be carried out. This is a simple operation as the medullary canal is already open and the regenerated bone is often of surprising good quality. It may even be possible to use a primary stem as opposed to a long revision stem, but this probably should not be done under nine months.

The presence of an IM nail and cerclage wires does not prevent the elimination of infection. As our brothers, the trauma surgeons, will attest the treatment of an infected non-union of the femur is an intramedullary nail.

This technique is seldom required. The author has used it in eight cases in the last 30 years. It is, however, extremely valuable in bailing out of an impossible revision, especially if strut allografts or modular long stems are not immediately available.