In his classic monograph entitled Low Friction Arthroplasty of the Hip, which was published in 1979, John Charnley dedicated a chapter to thromboembolic complications. The overall incidence of pulmonary embolism (PE) was approximately 8% and the incidence of death from PE approximately 1%. Surveys of orthopaedic surgeons who undertake total joint replacement conducted by The American Association of Hip and Knee Surgeons (AAHKS), 30 years later, showed that there was still no consensus as to the best form of prophylaxis with a wide variation of methods being used.

In the past 3 years, for the first time there is uniformity in the recommendations of the American Academy of Orthopaedic Surgeons (AAOS) and the American College of Chest Physicians (ACCP). Both groups have reached an agreement that the rate of DVT formation is not the ideal endpoint to use when assessing the efficacy of thromboprophylaxis after joint replacement, as had been done in previous drug trials. Most of these DVTs are asymptomatic and of questionable clinical significance. At least one recent study brings into question the association between the rate of DVT formation and that of subsequent symptomatic events. Both groups also focus on minimizing iatrogenic bleeding complications, which can lead to compromised clinical results, including limited movement and pain in the case of knee replacement and increased risk of infection in both knee and hip replacement. To further complete the uniformity of approach in the United States, the Center for Medicare and Medicaid Services (CMS), which administers the Surgical Care Improvement Program (SCIP) that monitors hospital compliance with VTE prophylaxis of hospitalised patients, has also changed their policy. Beginning January 2014, either aspirin or a compression device has been considered as acceptable measures for THR, TKR and hip fracture. The remarkable success reported from many centers with the use of aspirin and/or the use of a mobile compression device in patients without major risk factors, such as a prior history of symptomatic VTE, clearly indicate that aggressive pharmacoprophylaxis is not necessary for the vast majority of patients who undergo joint replacement.

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.

BACKGROUND

Patella resurfacing in TKA remains controversial. The purpose of this study was to compare the long-term clinical outcome in TKA in patients undergoing bilateral TKAs with one patella resurfaced and the other patella nonresurfaced.

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.

The use of hard-on-hard bearings, including ceramics peaked in the mid 2000's and has seen rapid decline since that time. Ceramics are not new to the market place but have had a 40 year history outside the U.S. The basis for renewed enthusiasm for ceramics included improved manufacturing, improved taper tolerances, higher strength, and lower wear. In spite of the major improvements concerns have been expressed with new generation ceramics by the experts and thought leaders in the field. The major concerns included complications related to modularity, continued problems with fracture and consequences of fracture, limited surgical options, and squeaking and impingement. The conclusion of one review article was that “although ceramics show promise as a lower wear articulation, manufacturing and design modifications and improvements will continue in an attempt to address the substantial concerns that persist”. Modifications have indeed occurred. The question is rather all of these concerns have been addressed and the answer is no. One proposed solution was a hybrid material of Alumina and Zirconia (Delta Ceramic). The advantages included higher strength, lower wear, more options and possibly less squeaking. Unfortunately the modest material improvements did not begin to overcome the obstacles to adopting this technology. High on this list is the problem with cost with the current health care environment unwilling to pay for expensive new technology that does not have proven value. A 2nd major issue is new technology must account for variability in surgeon performance in maximising margin for error. The medical legal environment is unforgiving of failure of new unproven options. Most of the old issues with ceramics have not been completely resolved. Delta Ceramic in particular, has increased cost with no demonstrated benefit.

A major problem is there is no known problem with metal or ceramic against cross-linked polyethylene bearing in terms of wear or osteolysis in the 10–15 year time frame. Among all the bearing articulations, metal-on-cross-linked performs the best. The persistent vexing problems with ceramics include impingement, liner breakage, and squeaking. Ceramic components do not tolerate component malposition which increases wear and squeaking. The problem is that a substantial percentage of hip replacements are put in outside of the ideal radiographic zone even at specialty centers. Breakage continues to be a problem especially with liners. There is also a need for complete rim exposure for concentric placement with impaction of liners which makes ceramics less compatible with small incision surgery. The problem of squeaking has not been solved by Delta Ceramic. Originally a case report appeared in the literature of squeaking with Delta Ceramic. Since that time a large scale study has showed that only 69% of Delta Ceramic hips were silent with up to 13% being associated with reproducible squeaking.

While a new generation of ceramics are better than the earlier generation and have lowered the fracture risk and increased intraoperative options, the current generation ceramics still provide far fewer options than a standard metal-on-cross-linked total hip. The current generation metal-on-cross-linked total hips have 10–15 year results that cannot be improved upon in terms of wear and osteolysis. Other unsolved problems include breaking, chipping and squeaking. Ceramic-on-ceramic is less tolerant of suboptimal position which leads to impingement, edge loading, and an increased incidence of squeaking. Until all of these problems are successfully addressed, ceramic-on-ceramic cannot be advocated for widespread use.

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 eighteen years of age or older with no known history of venous thromboembolism, coagulation disorder, or solid tumor. Use of the compression device began perioperatively 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 postoperatively to document any evidence of deep venous thrombosis or pulmonary embolism.

Of 3,060 patients, 28 (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.

The inability to consistently position components is associated with the major complications of hip replacement including instability, wear, liner breakage, limb length discrepancy, and limited function. This was a major catalyst for the demise of hard-on-hard bearings. The greatest challenge is accurate, reproducible positioning of acetabular component which is obtained in a surprisingly low percentage of cases. Other major issues include consistently obtaining proper limb length, offset, component sizing, and complete seating without fracture of either the acetabulum or the femur. There are two approaches to this issue; to either use virtual reality which applies technology that provides surrogates to direct visualization of components. The major issues with computer assisted techniques include questions of accuracy and increased time and cost. The other approach is to utilise intraoperative imaging which has been the gold standard traditionally, however, previously it has been a challenge to utilise intraoperative imaging without adding substantial time and cost. Historically intraoperative imaging has not been adopted because it disrupts work flow, the quality of images has been inadequate, and it has added too much additional time to allow for a series of repeat radiographs to be obtained.

Modifications of existing portable imaging that utilise direct radiography (DR plate technology) allow for intraoperative images that display within seconds. Imbedded software allows measurement of all parameters of interest. Three or 4 systems are currently in use, and this is not virtual reality but it is the gold standard. Advantages include higher quality images, faster service speed, minimal impact on OR work flow, eventual reduction in operating costs, elimination of processing of chemicals and film room/storage room, and most importantly the elimination of outliers and return to the operating room due to unexpected findings on recovery room radiographs.

Intraoperative imaging has been utilised at a number of centers in recent years and has led to numerous intraoperative changes to optimise component implantation in a surprisingly high percentage of cases. Advances in technology have made intraoperative digital imaging a practical feasible strategy to avoid outliers that increase complications and compromise results. The rapidly evolving technology makes this a very attractive option for optimising total hip component placement. In addition it is an excellent teaching tool that is rapidly embraced by residents and fellows and is an extremely effective in eliminating outliers.

In recent years, cementless stems have dominated the North American market. There are several categories of cementless stems, but in the past 20 years, the two most popular designs in the United States have been the extensively coated cylindrical cobalt-chrome (CoCr) stem and the proximally coated tapered titanium stem, which in recent years has become the most common. The 10 year survival for both stem types has been over 95% with a distinction made on factors other than stem survival, including thigh pain, stress shielding, complications of insertion, and ease of revision. Conventional wisdom holds that proximally coated titanium stems have less stress shielding, less thigh pain, and a higher quality clinical result. Recent studies, however, including randomised clinical trials have found that the incidence of thigh pain and clinical result is essentially equivalent between the stem types, however, there is a modest advantage in terms of stress shielding for a tapered titanium stem over an extensively coated CoCr stem. One study utilising pain drawings did establish that if a CoCr cylindrical stem was utilised, superior clinical results in terms of pain score and pain drawings were obtained with a fully coated versus a proximally coated stem. In spite of the lack of a clinically proven advantage in randomised trials, tapered titanium stems have been favored because of the occasional occurrence of substantial stress shielding, the increased clinical observation of thigh pain severe enough to warrant surgical intervention, ease of use of shorter tapered stems that involves removal of less trochanteric bone and less risk of fracture both at the trochanter and the diaphysis due to the shorter, and greater ease of insertion through more limited approaches, especially anterior approaches. When tapered stems are utilised, there may be an advantage to a more rectangular stem-cross section in patients with type C bone. In spite of the numerous clinical advantages of tapered titanium stems, there still remains a role for more extensively coated cylindrical stems in patients that have had prior surgery of the proximal femur, particularly for a hip fracture, which makes proximal fixation, ingrowth, and immediate mechanical stability difficult to assure consistently. Cement fixation should also be considered in these cases. While the market place and the clinical evidence strongly support routine use of tapered titanium proximally coated relatively short stems with angled rather than straight proximal lateral geometry in the vast majority of cases, there still remains a role for more extensively coated cylindrical and for specific indications.

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 eighteen 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 (twenty distal deep venous thromboses, three proximal deep venous thromboses, and five 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.

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 eighteen years of age or older with no known history of venous thromboembolism, coagulation disorder, or solid tumor. Use of the compression device began perioperatively 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 postoperatively to document any evidence of deep venous thrombosis or pulmonary embolism.

Of 3,060 patients, twenty-eight (0.92%) had venous thromboembolism (twenty distal deep venous thromboses, three proximal deep venous thromboses, and five 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 provides a non-inferior risk for developing venous thromboembolism compared with current pharmacological protocols reported in the literature.

In recent years, cementless stems have dominated the North American market. There are several categories of cementless stems, but in the past 20 years, the two most popular designs in the United States have been the extensively coated cylindrical cobalt-chrome (Co-Cr) stem and the proximally coated tapered titanium stem, which in recent years has become the most common. The 10 year survival for both stem types has been over 95% with a distinction made on factors other than stem survival, including thigh pain, stress shielding, complications of insertion, and ease of revision. Conventional wisdom holds that proximally coated titanium stems have less stress shielding, less thigh pain, and a higher quality clinical result. Recent studies, however, including randomised clinical trials have found that the incidence of thigh pain and clinical result is essentially equivalent between the stem types, however, there is a modest advantage in terms of stress shielding for a tapered titanium stem over an extensively coated Co-Cr stem. One study utilising pain drawings did establish that if a Co-Cr cylindrical stem was utilised, superior clinical results in terms of pain score and pain drawings were obtained with a fully coated versus a proximally coated stem. In spite of the lack of a clinically proven advantage in randomised trials, tapered titanium stems have been favored because of the occasional occurrence of substantial stress shielding, the increased clinical observation of thigh pain severe enough to warrant surgical intervention, ease of use of shorter tapered stems that involve removal of less trochanteric bone and less risk of fracture both at the trochanter and the diaphysis due to the shorter, and greater ease of insertion through more limited approaches, especially anterior approaches. When tapered stems are utilised, there may be an advantage to a more rectangular stem-cross-section in patients with type C bone. In spite of the numerous clinical advantages of tapered titanium stems, there still remains a role for more extensively coated cylindrical stems in patients that have had prior surgery of the proximal femur, particularly for a hip fracture, which makes proximal fixation, ingrowth, and immediate mechanical stability difficult to assure consistently. Cement fixation should also be considered in these cases. While the marketplace and the clinical evidence strongly support routine use of tapered titanium proximally coated relatively short stems with angled rather than straight proximal lateral geometry in the vast majority of cases, there still remains a role for more extensively coated cylindrical and for specific indications.

Wound complications are much more common following knee arthroplasty compared to hip arthroplasty. This is because of the precarious blood supply which contributes to the infection rate which is about twice as high. Many, if not most, infections are related to wound problems. Avoiding wound problems is a critical issue in joint replacement, more so in the knee than the hip. The volume of these procedures is growing rapidly. Infection continues to be a major complication. The incidence is not decreasing and infections are becoming more difficult to treat, because of resistant organisms. Also, the increasing number of procedures in patients with obesity and other risk factors makes wound management a major issue in knee replacement. Many wound problems are avoidable and can be minimised by care to detail by the surgeon.

Salvaging the problem wound is a major issue in total knee replacement currently in order to minimise infection, which remains a major issue and is frequently related to wound healing problems. The first step is identifying the patient at risk and either deferring surgery or optimising the patient to minimise the risk of wound healing problems and subsequent infection. Secondly, is appropriate soft tissue handling with careful attention to choosing the optimal skin incision. Third is taking steps to facilitate primary wound healing and absolutely minimising the risk of persistent drainage, particularly through the very judicious use of anticoagulants. Finally, the delayed wound healing and persistent drainage must be identified early and treated aggressively in order to minimise the risk of infection.

TKA is among the fastest growing interventions in medicine, with procedure incidence increasing the most in younger patients. Global knee scores have a ceiling effect and do not capture the presence of difficulty or dissatisfaction with specific activities important to patients.

We quantified the degree of residual symptoms and specific functional deficits in young patients who had undergone TKA.

In a national multicenter study, we quantified the degree of residual symptoms and specific functional deficits in 661 young patients (mean age, 54 years; range, 19–60 years; 61% female) at 1 to 4 years after primary TKA.

To eliminate observer bias, satisfaction and function data were collected by an independent, third-party survey center with expertise in administering medical outcomes questionnaires.

Overall, 89% of patients were satisfied with their ability to perform normal daily living activities, and 91% were satisfied with their pain relief. After TKA, 66% of patients indicated their knees felt normal, 33% reported some degree of pain, 41% reported stiffness, 33% reported grinding/other noises, 33% reported swelling/tightness, 38% reported difficulty getting in and out of a car, 31% reported difficulty getting in and out of a chair, and 54% reported difficulty with stairs. After recovery, 47% reported complete absence of a limp and 50% had participated in their most preferred sport or recreational activity in the past 30 days.

When interviewed by an independent third party, about 1/3 of young patients reported residual symptoms and limitations after modern TKA. We recommend informing patients considering surgery about the high likelihood of residual symptoms and limitations after contemporary TKA, even when performed by experienced surgeons in high-volume centers, and taking specific steps to set patients’ expectations to a level that is likely to be met by the procedure as it now is performed.

The major causes of revision total knee are associated with some degree of bone loss. The missing bone must be accounted for to insure success of the revision procedure, to achieve flexion extension balance, restore the joint line to within a centimeter of its previous level, and to assure a proper sizing especially the anteroposterior diameter of the femoral component. In recent years, clinical practice has evolved over time with a general move away from a structural graft with an increase in utilisation of metal augments. Alternatives include cement with or without screw fixation, rarely, with the most common option being the use of metal wedges. With the recent availability of highly porous augments, the role of metal augmentation has increased. Bone graft is now predominantly used in particulate form for contained defects with more limited use of structural graft. The role of the allograft-prosthetic composite has become more limited. For the elderly with osteopenia and massive bone loss, complete metal substitution with an oncology prosthesis has become more common.

The degree of bone loss is a major determinant of the management strategy. For contained defects less than 5 mm, cement alone, with or without screw supplementation, may be adequate. For greater than 5 mm, morselised graft is frequently used. For uncontained defects of up to 15 mm or more, metal augmentation is the first choice. Bone graft techniques can be utilised in this setting, however, these are more time consuming and technically demanding with little demonstrated advantage. For larger, uncontained defects, newer generation highly porous augments and step wedges are useful. Large contained defects can be dealt with utilising impaction grafting, similar to the hip impaction grafting technique. Massive distal defects are expeditiously managed with oncology defects in the case of periprosthetic fracture and/or massive osteolysis particularly when combined with osteopenia in an elderly, low demand patient. Surgeons must be familiar with an array of techniques in order to effectively deal with the wide spectrum of bone defects encountered during revision total knee arthroplasty.

After decades of clinical experience and hundreds of studies, the ideal method of deep vein thrombosis (DVT) prophylaxis remains controversial. One of the most widely quoted publications on the subject in recent years has been the guidelines published by the American College of Chest Physicians (ACCP). The seventh and eighth ACCP Conference on Antithrombotic Therapy and Prevention of Thrombosis were published in Chest in 2004 and 2008 respectively. The highest level recommendation (1-A) was reserved for Warfarin at a relatively high dose (target international normalised ratio (INR) of 2–3), Low Molecular Weight Heparin (LMWH), or Fondaparinux for a minimum of 10 days for both total hip and total knee replacement. These agents were recommended for all patients, regardless of their relative risk of bleeding or risk of venous thromboembolism (VTE). These recommendations were found to be aggressive by the standards of most orthopaedic surgeons and a number of issues were identified with the methodology and resulting recommendations of the ACCP including: The emphasis on multicentre randomised clinical trials that are enormously expensive and strongly weighted towards pharmaceutical sponsored studies, methodology that prevented inclusion of studies of lower cost, lower tech options such as aspirin or lower dose Warfarin since randomised trials on a large scale are not available due to lack of funding or pharmaceutical company interest in generic low-cost options, lack of consideration of pneumatic compression options such as newly available mobile foot pumps with chips for monitoring compliance, financial conflict of interest of virtually all of the authors of the guidelines and the fundamental problem with utilising asymptomatic DVT as a study endpoint. The concerns with the aggressive nature of these recommendations were confirmed by studies from two academic centres which reported a high incidence of wound and bleeding complications when changing to a 1-A protocol. Recent studies indicate that readmissions following joint replacement are much more likely to be due to wound drainage and bleeding complications than DVT or pulmonary embolism (PE). In response to these concerns, the AAOS released guidelines in 2008 that were updated in 2011. The resulting recommendations represented a dramatic departure from the ACCP guidelines. Clinically crucial endpoints such as PE and death were utilized in the analysis rather than asymptomatic DVT, which was the criteria utilised by the Chest Physicians and the 2011 recommendations also considered symptomatic DVT. The AAOS guidelines consider patient risk category rather than making a uniform recommendation for all patients. Much more discretion is given to surgeons to utilise less aggressive prophylactic strategies including aspirin and foot pumps.

In 2012, the ninth edition of the ACCP guidelines was published and many of the concerns previously expressed over prior editions were successfully addressed. Conflict of interest among the authors was much less of an issue, there was more attention placed on symptomatic events and clinically important complications, and a wider scope of literature was considered. The resulting guidelines represented a dramatic departure from previous recommendations. Aspirin and pneumatic compression were elevated to level 1 recommendation status along with potent drug regimens such as injectable drugs (LMWH and Xa inhibitor) as well as the new oral Xa inhibitors and antithrombin agents. When pneumatic compression devices are utilised, the use of a battery powered device capable of recording compliance was recommended. Patient risk status as well as patient preference were also considered. The new ACCP guidelines have successfully addressed many of the concerns previously addressed and are much more in line with the AAOS guidelines. It is anticipated that the federal Surgical Care Improvement Project (SCIP) guidelines for VTE prophylaxis will be released in 2013 and will also embrace the changes recommended by the ACCP. It is further likely that the AAOS and ACCP guidelines are close enough that they may well join forces in the near future and release a single unified document.

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 of 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 multicentre survey was conducted by an independent university medical interviewing centre 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 centres 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.

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 utilisation and investigation of this procedure.

Introduction: Third generation fixation systems allow for the retightening of cables, and are associated with high rates of trochanteric union. This is a prospective study undertaken to evaluate the outcome of the first 40 patients treated with a third generation cable plate and trochanteric hook system.

Methods: 36 patients treated by two revision hip arthroplasty surgeons using a third generation cable plate system were enrolled and followed up. These included 28 females and 12 males with an average age of 64 (range: 48–91). Large hooks were used in 30 with an average of 4.8 cables (range: 4–9). The need to retighten cables intra-operatively was noted. Clinical and radiographic follow-up was undertaken at 2 years.

Results: A third generation fixation system was used for 16 peri-prosthetic fractures, 6 trochanteric non unions, 5 structural femoral allografts, 6 complex revisions and for trochanteric advancement in 3 cases. The first cable tightened was loose by the end of the procedure in the majority of cases and had to be retightened. There were no cases of fretting or cable breakage. Two further tro-chanteric non unions needed re-fixation and bone grafting in a further procedure

Discussion and Conclusion: Third generation cable system allow for re-tightening, as the cable is not damaged by the crimping mechanism. This facility appears critical as some retightening is invariably required in the process of applying this type of device. There were only 2 re-operations for trochanteric non unions, but the overall outcomes were otherwise excellent, with no fretting or cable breakage. Modern cable systems afford improved, more flexible trochanteric fixation possibilities.

Serological tests including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are frequently used in the preoperative workup to screen for periprosthetic infection (PPI) in total hip arthroplasty (THA). The cut-off points reported in the literature are arbitrarily chosen by investigators. Similarly, the values used in laboratories to distinguish elevated results vary from one institute to another. Therefore, we intended to define the appropriate cut-off points of ESR and CRP that can be used to differentiate infection from aseptic failure of THA.

A review of our joint registry database revealed that 515 THA revisions (131 infected cases) were performed during 2000–2005. Intraoperative samples for culture were taken in all cases. The criteria used for diagnosis of infection were a positive intraoperative culture on solid media, presence of an abscess or sinus tract that communicated with the joint, positive preoperative aspiration culture, and/or elevated fluid cell count and neutrophil differential of the aspirated fluid. Non-infected patients with confounding factors that can elevate ESR and CRP including collagen vascular disease, inflammatory arthropathy, malignancy, and urinary tract infection were excluded. Receiver operator curves were used to determine the ideal cut-off point for both ESR and CRP.

The mean value of ESR in the infected group (77mm/ hr) was significantly higher compared to that of the non-infected cohort (29mm/hr) (p=0.0001). Similarly, infected patients presented with a greater mean CRP (9.8 mg/dl) than their non-infected cohort (1.48 mg/ dl) (p=0.0001). The infection threshold for ESR was 45mm/hr with a sensitivity of 85% and specificity of 79%, while the optimal cut-off value for CRP was defined as 1.6 mg/dl which yielded a sensitivity of 86% and specificity of 83%.

The optimal threshold values we determined are higher than the arbitrarily chosen values cited in the literature for ESR (30mm/hr) and CRP (1mg/dl). Although it has been previously reported that the sensitivity and specificity of CRP are far greater than that of ESR, we found that the two tests have comparable diagnostic value.

One of the routinely used intraoperative tests for diagnosis of periprosthetic infection (PPI) is Gram stain that is reported to carry a very high specificity and a poor sensitivity. However, it is not known if the result of this test can vary according to the type of joint affected or the number of specimen samples collected. This study intended to examine the role of this diagnostic test in a large cohort of patients from single institution.

A review of our joint registry database revealed that 453 total knee arthroplasty (TKA) and 551 total hip arthroplasty (THA) of which 171 and 150 cases were respectively infected underwent revision surgery during 2000–2005 and had intraoperative cultures available for interpretation. A positive gram stain was defined as the visualisation of bacterial cells or ‘many leukocytes’ (> 5 per high power field) under the smear. The sensitivity, specificity, and predictive values of each individual diagnostic arm of Gram stain were determined. Combinations were performed in series that require both tests to be positive to confirm infection and in parallel that necessitate both tests to be negative to rule out infection. This analysis was performed for THA and TKA separately and later compared for each joint type.

The presence of organism cells and ‘many’ neutrophils on a Gram smear had high specificity (98%–100%) and positive predictive value (89%–100%) in both THA and TKA. The sensitivities (30%–50%) and negative predictive values (70%–79%) of the two tests were low as expected among both joint types. When the two tests were combined in series the specificity and positive predictive value were absolute (100%). The sensitivity (43%–64%) and the negative predictive value (82%) improved among both THA and TKA.

The presence of organisms or ‘many’ leukocytes on the Gram smear can confirm PPI in TJA. As expected, the sensitivity and negative predictive value of the two tests were low, and therefore infection could not be safely ruled out. Although the two diagnostic arms of Gram stain can be combined to achieve improved negative predictive value (82%), Gram stain continues to have poor value in ruling out PPI. With the advances in the field of molecular biology, novel diagnostic modalities need to be designed that can replace these traditional and poor tests.

Introduction: Intraoperative tissue culture remains the “gold standard” in diagnosing periprosthetic infection (PPI). However, an organism is not always cultured and this has been attributed to the fact that preoperative antibiotics were administered. This study intends to examine if preoperative antibiotics prevent isolation of intraoperative organisms.

Methods: 91 total joint arthroplasty patients diagnosed with PPI during (1999–2005) and who had positive aspiration culture were included in the study. All intravenous antibiotics that were given to the patient within seven days of surgery were documented. The total number of positive intraoperative fluid and tissue samples of patients who did and did not receive antibiotics was calculated. Susceptibility of the organism(s) to antibiotics was determined by antibiogram of the preoperative and intraoperative culture.

Results: 60 out of 91 patients received preoperative antibiotics within seven days of surgery. Antibiotics prevented isolation of an intraoperative organism in 6 out of the 60 (10%) cases. All of the 31 patients who did not receive any preoperative antibiotics had positive intraoperative cultures. Chi-square analysis revealed no significant difference between giving preoperative antibiotics within 7 days and isolating an intraoperative organism (p=0.068). Giving antibiotics that specifically targets the culprit organism did not significantly affect the fluid (p=0.585) or tissue culture yield (p=0.152) either.

Discussion: Although, giving preoperative antibiotics can prevent isolation of intraoperative organisms in 10% of cases, this is not statistically or clinically significant in patients with positive aspiration cultures because the organism is known beforehand. However, it is clinically and medicolegally relevant to withhold antibiotics in patients with negative aspiration cultures since the postoperative treatment antibiotic is tailored according to the organism cultured.