Introduction. Reverse total shoulder arthroplasty (RTSA) is rapidly being adopted as the standard procedure for a growing number of shoulder arthropathies. Though short-term outcomes are promising, mid- and long-term follow-ups present a number of complications – among them, humeral stem and glenosphere component loosening. Though not the primary complication, previously reported aseptic loosening required revision in 100% of cases. As the number of patients undergoing RTSA increases, especially in the younger population, it is important for surgeons to identify and utilize prostheses with stable long-term fixation. It has previously been shown in the hip and knee literature that implant migration in the first two years following surgery is predictive of later failure due to loosening in the 5=10-year postoperative window. The purpose of this study is to, for the first time, evaluate the pattern and total magnitude of implant migration in reverse shoulder arthroplasty using the gold standard imaging technique radiostereometric analysis (RSA). Methods. Forty patients were prospectively randomized to receive either a cemented or press-fit humeral stem, and a glenosphere secured to the glenoid with either autologous bone graft or 3D printed porous titanium for primary reverse total shoulder arthroplasty. Following surgery, participants are imaged using RSA, a calibrated, stereo x-ray technique. Radiographs are acquired at 6 weeks (baseline), 3 months, 6 months, 1 year, and 2 years. Migration of the humeral stem and glenosphere at each time point is compared to baseline. Migration of the prostheses is independently compared between humeral
Introduction. Femoral component loosening is one of the most common failure modes in cementless total hip arthroplasty (THA). Patient age, weight, gender, osteopenia, stem design and Dorr-C bone have all been proposed as risk factors for poor fixation and subsequent stem subsidence and poor outcome. With the increased popularity of CT-based assistive technologies in THA, (Stryker MAKO and Corin OPSTM), we sought to develop a technique to predicted femoral
The decreased bone mass or local osteoporosis at the proximal femur is often recognized in patients of rheumatoid arthritis (RA). In total hip arthroplasty (THA), the cancellous bone will be lost when rasping technique is applied for the preparation of stem insertion. In addition, cutting or elongation for contracted muscles around the hip joint can be required to insert the stem. To avoid these problems, the non-broaching, non-rasping impaction technique for the stems was applied in THA for the patients with RA. We report clinical and radiographic results of this method. In surgery, the femoral neck was cut and prepared without using a box chisel, reamer or broaches, instead, a series of trial stems were used with the method of impaction technique. After impaction of cancellous bone with the final size of the trial stem, the stem is fixed by bone cement without taking any cement mantle. Full weight bearing was allowed for all patients from the next day of the surgery. We investigated short-term clinical and radiographic results and the incidence of complication that was related to this technique. Post-operative radiological results with the minimum follow-up of 12 months after surgery were analyzed in 31 joints (25 cases) with this technique. The mean age at the time of surgery was 66.3 years (46∼82). The mean duration after surgery was 62 months (14∼108).Introduction
Materials and Methods
Femoral stress shielding in cementless THA is a potential complication commonly observed in cementless distally loading press-fit stems. Long-term metaphyseal fixation and proximal load transfer is desired. Is routine autologous metaphyseal bone impaction and proximal primary stability an answer to this goal? This prospective study describes long-term femoral bone remodeling and load transfer in cementless THA at a mean of 17 years (range: 15 to 20 years) in 208 consecutive fully HA-coated stems (Corail). All primary THA were performed by one group of surgeons between 1986 and 1991. The concept of surgical technique included impaction of autologous metaphyseal bone using bland femoral broaches until primary stability was achieved without distal press-fit. Radiographic evaluation revealed a total of five (2.4%) stems with periprosthetic osteolysis, which were associated with eccentric polyethylene wear. They were either revised or awaiting revision. The remaining 97.6% stems revealed desired proximal load transfer in the metaphysis (52%) or in both metaphysis and diaphysis (48%). Distal stress shielding was not observed and was considered to be related to: impaction of metaphyseal bone, bland broaches, HA coating, and prosthetic design. Biological autologous bone impaction of the metaphysis provides both primary stem stability and successful longterm osteointegration with the Corail stem after 20 years. The surgical technique of proximal autologous bone impaction rather than extraction of cancellous bone material and the use of a fully HA coated stem without distal press-fit show encouraging longterm results in THA.
The demand for revision total knee arthroplasty (TKA) has grown significantly in recent years. The two major fixation methods for stems in revision TKA include cemented and ‘hybrid’ fixation. We explore the optimal fixation method using data from recent, well-designed comparative studies. We performed a systematic review of comparative studies published within the last 10 years with a minimum follow-up of 24 months. To allow for missing data, a random-effects meta-analysis of all available cases was performed. The odds ratio (OR) for the relevant outcome was calculated with 95% confidence intervals. The effects of small studies were analyzed using a funnel plot, and asymmetry was assessed using Egger's test. The primary outcome measure was all-cause failure. Secondary outcome measures included all-cause revision, aseptic revision and radiographic failure. There was a significantly lower failure rate for hybrid stems when compared to cemented stems (p = 0.006) (OR 0.61, 95% CI 0.42-0.87). Heterogeneity was 4.3% and insignificant (p = 0.39). There was a trend toward superior hybrid performance for all other outcome measures including all-cause re-revision, aseptic re-revision and radiographic failure. Recent evidence suggests a significantly lower failure rate for hybrid stems in revision TKA. There is also a trend favoring the use of hybrid stems for all outcome variables assessed in this study. This is the first time a significant difference in outcome has been demonstrated through systematic review of these two modes of
Instability after TKA can result from ligament imbalance, attenuation of soft tissues, or ligament disruption. Flexion instability has been reported after both CR and PS TKA. However, the clinical manifestations of flexion instability can be quite variable. Symptoms of flexion instability include pain and swelling after activity. Bracing occasionally can be helpful. Revision options to treat flexion instability include tibial insert exchange and revision to increase constraint. However, more favorable results have been reported using implants with varus-valgus constraint. Constrained mechanisms include a varus-valgus constrained PS post or hinge. The constrained post relies on the mechanical function of the post to provide stability which may deform or wear in-vivo leading to recurrent instability if used for a completely deficient collateral ligament. The hinge, which provides more rigid constraint, is indicated for collateral ligament deficiency. However, the additional constraint also results in greater bone-implant interface stresses, which may be mitigated by use of
The most common classification of periprosthetic femoral fractures is the Vancouver classification. The classification has been validated by multiple centers. Fractures are distinguished by location, stability of the femoral component, and bone quality. Although postoperative and intraoperative fractures are classified using the same three regions, the treatment algorithm is slightly different. Type A fractures involve the greater and lesser trochanter. Fractures around the stem or just distal to the stem are Type B and subcategorised depending on stem stability and bone quality. Type C fractures are well distal to the stem and are treated independent of the stem with standard fixation techniques. The majority of fractures are either B1 (stable stem) or B2 (unstable stem). The stem is retained and ORIF of the fracture performed for B1 fractures. B2 and B3 fractures require stem revision with primary
The objective of this study was to evaluate the short term clinical and radiological results of a new short stem hip implant. In 29 consecutive patients suffering from osteoarthritis with 33 affected hip joints, the clinical and radiological results of 33 cementless hip arthroplasties using a cementless implanted short stem prosthesis type Aida and a cementless cup type Ecofit were evaluated prospectively between October 2009 and June 2015 in two hospitals. The median age of patients at time of surgery was 55 years (range, 30–71 years), 23 male and 10 female patients were included in the study. The median clinical follow up was 24 months (range, 1.5–51 months), and the median radiological follow up was 12 months (range, 1–51 months). Two patients were lost to follow up and two patients had only one immediate postoperative x- ray. The Harris Hip Score improved from a median preoperative value of 53 to a median postoperative value of 93 at follow up. Radiological analysis showed that 19 stems (58%) showed stable bony ingrowth, five cases (15%) showed stable fibrous ingrowth. Four cases need further follow up for proper evaluation of
INTRODUCTION. The Woodpecker pneumatic broaching system facilitates femoral preparation to achieve optimal primary
Background:. For hip prostheses, short stems allow easy insertion and reduce thigh pain risk, and are therefore suitable for Minimally Invasive Surgery. However, clinical outcome depends on sufficient initial fixation in the proximal femoral component. Revelation stems are designed to increase medullary cavity occupancy in the proximal femoral component and allow physiological load transmission within this component. Theoretically, on initial fixation of the proximal part of the
Aim. The objective of this study was to evaluate the intermediate term clinical and radiological results of a new short stem hip implant. Methods. In 20 consecutive patients suffering from osteoarthritis with 25 affected hip joints (five cases were bilateral), the clinical and radiological results of 25 hip arthroplasties performed in one hospital between October 2009 and May 2014 through a minimally invasive anterolateral approach using a cementless short stem prosthesis type Aida and a cementless cup type Ecofit with a ceramic on ceramic pairing were evaluated prospectively. The median age of patients at time of surgery was 60 years (range, 42–71 years), 15 male (4 were bilateral) and 5 female patients (one was bilateral) were included in the study. The median clinical follow up was 30 months (range, 2–88 months), and the median radiological follow up was 30 months (range, 2–88 months). Results. Harris Hip Score improved from a median preoperative value of 53 to a median postoperative value of 96 (range, 73–100) at follow up. 22 hips (88%) showed an excellent postoperative Harris Hip Score, 2 hips (8%) a good postoperative Harris Hip Score, and one hip (4%) a fair postoperative Harris Hip Score. Only two patients complained of postoperative thigh pain. Regarding patient satisfaction, 15 patients (60%) were very satisfied, 10 patients (40%) were satisfied. None was unsatisfied. Radiological analysis showed that 19 stems (76%) were with stable bony ingrowth, two cases (8%) showed stable fibrous ingrowth. Four cases need further follow up for proper evaluation of
Introduction. Proper initial
INTRODUCTION. Recently, short shaped stem becomes popular in total hip arthroplasty (THA). Advantages of the short stem are preserving femoral bone stock, thought to be less thigh pain, suitable for minimally invasive THA. However, bony reaction around the short stem has not been well known. The purpose of this study was to compare the two years difference of radiographic change around the standard tapered round stem with the shorter tapered round stem. MATERIALS AND METHODS. Evaluation was performed in 96 patients (100 joints) who underwent primary THA. Standard tapered round stem (Bicontact D stem) was used in 44 patients from January 2011 to May 2013. Shorter stem (Bicontact E stem) was used in 56 patients from May 2015 to March 2016. The proximal shapes of these two stems are almost the same curvature. The mean age at surgery was 64 years. The mean BMI at surgery was 24.0 kg/m. 2. Eighty-six patients had osteoarthrosis and 10 patients had osteonecrosis. Evaluation was performed 2 years after surgery with standard AP radiographs. The OrthoPilot imageless navigation system was used during surgery. Evaluation of the
Stems are a crucial part of implant stabilization in revision total knee arthroplasty. In most cases the metaphyseal bone is deficient, and stabilization in the diaphyseal cortical bone is necessary to keep the implant tightly fixed to bone and to prevent tilt and micromotion. While sleeves and cones can be effective in revision total joint arthroplasty, they are technically difficult and may lead to major bone loss in cases of loosening or infection, especially if the stem is cemented past the cone. A much more conservative method is to ream the diaphysis to the least depth possible to achieve tight circumferential fixation, and to apply porous augments to the undersurface of the tibial tray or inner surface of the femoral component to allow them to bottom out against the bone surface and apply compressive load. If a robust, strong taper, stem and component combination is used, rim contact on only one side is necessary to achieve rigid permanent fixation. Porous and non-porous stems are available. The non-porous stems should have a spline surface that engages the diaphyseal bone and achieves rigid initial fixation but does not provide long-term axillary support. In that way the porous rim-engaging surface can bear compressive load and finally unload the stem and taper junction. Correctly designed stems do not stress relieve unless they are porous-coated. In situations where metaphyseal bone is not available, porous-coated stems that link to hinge prostheses are a very important part of the armamentarium in complex revision arthroplasty. Use of stems requires experience and special technique. Slight underreaming and initial scratch fit are necessary techniques. This does not result in tight fixation every time because split of the cortex does occasionally occur. In most cases these splits do not need to be repaired, but when there is a question, an intra-operative x ray should be taken and the surgeon should be prepared to repair the fracture. Stems are an essential part of revision total knee arthroplasty. A tightly fit stem in the diaphysis is necessary for fixation when metaphyseal bone is deficient. No amount of cement pressed into the deficient metaphyseal bone will substitute for rigid
The Failed Femoral Neck Fracture. For the young patient: Attempt to preserve patient's own femoral head. Clinical results reasonably good even if there are patches of avascular necrosis. Preferred methods of salvage: valgus-producing intertrochanteric femoral osteotomy: puts the nonunion under compression. Other treatment option: Meyer's vascularised pedicle graft. For the older patient: Most reliable treatment is prosthetic replacement. Decision to use hemiarthroplasty (such as bipolar) or THA based on quality of articular cartilage, perceived risk of instability problem. In most patients THA provides higher likelihood of excellent pain relief. Specific technical issues: (1) hardware removal: usually remove after hip has first been dislocated (to reduce risk of femur fracture); (2) Hip stability: consider methods to reduce dislocation risk: larger diameter heads/dual mobility/anteriorly-based approaches; (3) Acetabular bone quality: poor because it is not sclerotic from previous arthritis; caution when impacting a pressfit cup; low threshold to augment fixation with screws; don't overdo reaming; just expose the bleeding subchondral bone. A reasonable alternative is a cemented cup. The Failed Intertrochanteric Hip Fracture. For the young patient: Attempt to salvage hip joint with nonunion takedown, autogenous bone grafting and internal fixation. For the older patient: Decision to preserve patient's own hip with internal fixation versus salvage with hip arthroplasty should be individualised based on patient circumstances, fracture pattern, bone quality. THA is an effective salvage procedure for this problem in older patients. If prosthetic replacement is chosen special considerations include:. THA vs. hemiarthroplasty: hemiarthroplasty better stability; THA more reliable pain relief. Removal of hardware: be prepared to remove broken screws in intramedullary canal. Management of bone loss: bone loss to level of lesser trochanter common. Often requires a calcar replacement implant. Proximal calcar build-up size dictated by bone loss. Length of stem: desirable to bypass screw holes from previous fixation, if possible.
Mastering the Art of Cemented Femoral
Periprosthetic fractures around the femur during and after total hip arthroplasty (THA) remain a common mode of failure. It is important therefore to recognise those factors that place patients at increased risk for development of this complication. Prevention of this complication, always trumps treatment. Risk factors can be stratified into: 1. Patient related factors; 2. Host bone and anatomical considerations; 3. Procedural related factors; and 4. Implant related factors. Patient Factors. There are several patient related factors that place patients at risk for development of a periprosthetic fracture during and after total hip arthroplasty. Metabolic bone disease, particularly osteoporosis increases the risk of periprosthetic fracture. In addition, patients that smoke, have long term steroid use or disuse, osteopenia due to inactivity should be identified. A metabolic bone work up and evaluation of bone mineralization with a bone densitometry test can be helpful in identifying and implementing treatment prior to THA. Pre-operative Host Bone and Anatomic Considerations. In addition to metabolic bone disease the “shape of the bone” should be taken into consideration as well. Dorr has described three different types of bone morphology (Dorr A, B, C), each with unique characteristics of size and shape. It is important to recognise that not one single cementless implant may fit all bone types. The importance of templating a THA prior to surgery cannot be overstated. Stem morphology must be appropriately matched to patient anatomy. Today, several types of cementless stem designs exist with differing shape and areas of fixation. It is important to understand via pre-operative templating which stem works best in what situation. Procedural Related Factors. There has been a resurgence in interest in the varying surgical approaches to THA. While the validity and benefits of each surgical approach remains a point of debate, each approach carries with it its own set of risks. Several studies have demonstrated increased risk of periprosthetic fractures during THA with the use of the direct anterior approach. Risk factors for increased risk of periprosthetic fracture may include obesity, bone quality and stem design. Implant Related Factors. As mentioned there are several varying cementless implant shapes and sizes that can be utilised. There is no question that cementless fixation remains the most common mode of fixation in THA. However, one must not forget the role of cemented fixation in THA. Published results on long term fixation with cemented stems are comparable if not exceeding those of press fit fixation. In addition, the literature is clear that cemented fixation in the elderly hip fracture patient population is associated with a lower risk of periprosthetic fracture and lower risk of revision. The indication and principles of cemented
Cementless femoral stems of many designs now provide dependable long-term fixation and excellent, near normal function in patients of all ages, sexes and level of activity. However, a number of issues related to cementless
Aim. One of the most challenging problems in total knee arthroplasty (TKA) is periprosthetic infection. A major problem that arises in septic revision TKA (RTKA) are extended bone defects. In case of extended bone defects revision prostheses with metaphyseal sleeves are used. Only a few studies have been published on the use of metaphyseal sleeves in RTKA - none were septic exclusive. The aim of our study was to determine the implant survival, achieved osseointegration as well as the radiological mid-term outcomes of metaphyseal sleeve fixation in septic two-stage knee revision surgery. Method. Clinical and radiological follow-up examinations were performed in 49 patients (25 male and 24 female). All patients were treated with a two-stage procedure, using a temporary non-articulating bone cement spacer. The spacer was explanted after a median of 12 weeks (SD 5, min. 1 – max. 31) and reimplantation was performed, using metaphyseal sleeves in combination with
Despite the best of technique, when faced with a sub-capital or per-trochanteric fracture, inevitably there are failures of proximal fixation. These situations provide unique challenges for the reconstructive surgeon. While there are specific issues related to either sub-capital or per-trochanteric fractures, there also are many commonalities. The causes of failure are nonunion, malunion, failure of fixation or avascular necrosis. In all cases, it is imperative to rule out infection. Since the surgery is now elective, the patient's medical status must be optimised prior to the intervention. Basic surgical principles apply to both fracture types. Use the old incision (if possible) and choose an approach that can be extensile. Of course, the old hardware needs to be removed – this task can be quite frustrating, so good preparation and patience is imperative. Retrieve old operative notes to identify the type of hardware so that any special tools needed are available. Hardware can be intra-osseous in location and excavation of the hardware may require bone osteotomy. These patients are at higher risk of post-operative dislocation, so absolute hip stability must be achieved and confirmed in the OR. Bigger heads and dual mobility options improve stability provided that the components are properly positioned and offset and leg length are restored. Subcapital fractures provide certain specific issues related to stem choice. While, my bias is towards THA because of better chance of complete pain relief, especially in community ambulators, certainly bipolar arthroplasties can be a satisfactory solution.