Comparison Between Orthopaedic Trauma Versus Arthroplasty Fellowship Training on Outcomes of Total Hip Arthroplasty for Femoral Neck Fracture.

BACKGROUND: This study aimed to identify differences in patient characteristics, perioperative management methods, and outcomes for total hip arthroplasty (THA) for femoral neck fracture (FNF) when performed by orthopaedic surgeons who have arthroplasty versus orthopaedic trauma training. METHODS: This study was a multicenter retrospective review of 636 patients who underwent THA for FNF between 2010 and 2019. There were 373 patients who underwent THA by an arthroplasty surgeon, and 263 who underwent THA by an orthopaedic trauma surgeon. Comorbidities, management methods, and outcomes were compared between patients operated on by orthopaedic surgeons who had arthroplasty versus trauma training. RESULTS: Arthroplasty-trained surgeons had shorter operative times (102 versus 128 minutes, P < .0001) and utilized tranexamic acid more frequently than trauma-trained surgeons (48.8 versus 18.6%, P < .0001). Orthopaedic trauma surgeons more frequently utilized an anterior approach. Patients of arthroplasty-trained surgeons had lower rates of complications including pulmonary embolism (1.6 versus 6.5%, P = .0019) and myocardial infarction (1.6 versus 11.0%, P < .0001). Similarly, patients of arthroplasty-trained surgeons were discharged faster (5.3 versus 7.9 days, P < .0001) with greater ambulation capacity (92.2 versus 57.2 feet, P < .0001). Dislocation, periprosthetic joint infection, and revision were similar between both groups. When adjusted for covariates, there was no difference in 90-day, 1-year, or 2-year mortality. CONCLUSION: A THA performed for FNF by arthroplasty surgeons was associated with lower in-hospital morbidities and improved functional statuses at discharge. However, mortalities and complications after discharge were similar between both specialties when adjusted for confounding variables. Optimization of protocols may further improve outcomes for THA for FNF.

Effect of Fracture Type, Treatment, and Surgeon Training on Reoperation After Vancouver B Periprosthetic Femur Fractures.

BACKGROUND: The treatment of Vancouver B periprosthetic proximal femur fractures (PPFFs) is complex due to the overlap between arthroplasty and orthopedic trauma techniques. Our purpose was to assess the effects of fracture type, treatment difference, and surgeon training on the risk of reoperation in Vancouver B PPFF. METHODS: A collaborative research consortium of 11 centers retrospectively reviewed PPFFs from 2014 to 2019 to determine the effects of variations in surgeon expertise, fracture type, and treatment on surgical reoperation. Surgeons were classified as per fellowship training, fractures using the Vancouver classification, and treatment as open reduction internal fixation (ORIF) or revision total hip arthroplasty with or without ORIF. Regression analyses were performed with reoperation as the primary outcome. RESULTS: Fracture type (Vancouver B3 versus B1: odds ratio [OR]: 5.70) was an independent risk factor for reoperation. No differences were found in reoperation rates with treatment (ORIF versus revision: OR 0.92, P = .883). Treatment by a nonarthroplasty-trained surgeon versus an arthroplasty specialist led to higher odds of reoperation in all Vancouver B fracture (OR: 2.87, P = .023); however, no significant differences were seen in the Vancouver B2 group alone (OR: 2.61, P = .139). Age was a significant risk factor for reoperation in all Vancouver B fractures (OR: 0.97, P = .004) and in the B2 fractures alone (OR: 0.96, P = .007). CONCLUSION: Our study suggests that age and fracture type affect reoperation rates. Treatment type did not affect reoperation rates and the effect of surgeon training is unclear.

Trends of Prosthetic Joint Infection Organisms and Recurrence for a Single High-Volume Arthroplasty Surgeon Over 20 Years.

BACKGROUND: Prosthetic joint infection (PJI) is a morbid complication following total joint arthroplasty (TJA). PJI diagnosis and treatment has changed over time, and patient co-management with a high-volume musculoskeletal infectious disease (MSK ID) specialist has been implemented at our institution in the last decade. METHODS: We retrospectively evaluated all consecutive TJA patients treated for PJI between 1995 and 2018 by a single high-volume revision TJA surgeon. Microbial identities, antibiotic resistance, prior PJI, and MSK ID consultation were investigated. RESULTS: In total, 261 PJI patients (median age 66 years, interquartile range 57-75) were treated. One-year and 5-year reinfection rates were 15.8% (95% confidence interval [CI] 11.6-20.7) and 22.1% (95% CI 17.0-27.7), respectively. Microbial identities and antibiotic resistances did not change significantly over time. Despite seeing more prior PJI patients (53.3% vs 37.6%, P = .012), MSK ID-managed patients had similar infection rates as non-MSK ID-managed patients (hazard ratio [HR] 1.02, 95% CI 0.6-1.75, P = .93). Prior PJI was associated with higher reinfection risk (HR 2.39, 95% CI 1.39-4.12, P = .002) overall and in patients without MSK ID consultation, specifically (HR 2.78, 95% CI 1.37-5.65, P = .005). This risk was somewhat lower and did not reach significance in prior PJI patients with MSK ID consultation (HR 1.97, 95% CI 0.87-4.48, P = .106). CONCLUSION: We noted minimal differences in microbial/antibiotic resistances for PJI over 20 years in a single institution, suggesting current standards of PJI treatment remain encouragingly valid in most cases. MSK ID involvement was not associated with lower reinfection risk overall; however, in patients with prior PJI, the risk of reinfection appeared to be somewhat lower with MSK ID involvement. LEVEL OF EVIDENCE: Level IV-Case Series.

What Is the Prevalence of Burnout, Depression, and Substance Use Among Orthopaedic Surgery Residents and What Are the Risk Factors? A Collaborative Orthopaedic Educational Research Group Survey Study.

BACKGROUND: Burnout and depression among healthcare professionals and trainees remain alarmingly common. In 2009, 56% of orthopaedic surgery residents reported burnout. Alcohol and illicit drug use are potential exacerbating factors of burnout and depression; however, these have been scarcely studied in residency populations. QUESTIONS/PURPOSES: (1) What proportion of orthopaedic residents report symptoms of burnout and depression? (2) What factors are independently associated with an orthopaedic resident reporting emotional exhaustion, depersonalization, low personal accomplishment, and depression? (3) What proportion of orthopaedic residents report hazardous alcohol or drug use? (4) What factors are independently associated with an orthopaedic resident reporting hazardous alcohol or drug use? METHODS: We asked 164 orthopaedic surgery programs to have their residents participate in a 34-question internet-based, anonymous survey, 28% of which (46 of 164) agreed. The survey was distributed to all 1147 residents from these programs, and 58% (661 of 1147) of these completed the survey. The respondents were evenly distributed among training years. Eighty-three percent (551 of 661) were men, 15% (101 of 661) were women, and 1% (nine of 661) preferred not to provide their gender. The survey asked about demographics, educational debt, sleep and work habits, perceived peer or program support, and substance use, and validated instruments were used to assess burnout (abbreviated Maslach Burnout Inventory), depression (Patient Health Questionnaire-2), and hazardous alcohol use (Alcohol Use Disorder Identification Test-Consumption). The main outcome measures included overall burnout, emotional exhaustion, depersonalization, low personal accomplishment, depression, and hazardous alcohol and drug use. Using the variables gathered in the survey, we performed an exploratory analysis to identify significant associations for each of the outcomes, followed by a multivariable analysis. RESULTS: Burnout was reported by 52% (342 of 661) of residents. Thirteen percent of residents (83 of 656) had positive screening results for depression. Factors independently associated with high emotional exhaustion scores included early training year (odds ratio 1.15; 95% confidence interval, 1.01-1.32; p = 0.03) unmanageable work volume (OR 3.13; 95% CI, 1.45-6.67; p < 0.01), inability to attend health maintenance appointments (OR 3.23; 95% CI, 1.69-6.25; p < 0.01), lack of exercise (OR 1.69; 95% CI, 1.08-2.70; p = 0.02), and lack of program support (OR 3.33; 95% CI, 2.00-5.56; p < 0.01). Factors independently associated with depersonalization included early training year (OR 1.27; 95% CI, 1.12-1.41; p < 0.01), inability to attend health maintenance appointments (OR 2.70; 95% CI, 1.67-4.35; p < 0.01), and lack of co-resident support (OR 2.52; 95% CI, 1.52-4.18; p < 0.01). Low personal accomplishment was associated with a lack of co-resident support (OR 2.85; 95% CI, 1.54-5.28; p < 0.01) and lack of program support (OR 2.33; 95% CI, 1.32-4.00; p < 0.01). Factors associated with depression included exceeding duty hour restrictions (OR 2.50; 95% CI, 1.43-4.35; p < 0.01) and lack of program support (OR 3.85; 95% CI, 2.08-7.14; p < 0.01). Sixty-one percent of residents (403 of 656) met the criteria for hazardous alcohol use. Seven percent of residents (48 of 656) reported using recreational drugs in the previous year. Factors independently associated with hazardous alcohol use included being a man (OR 100; 95% CI, 35-289; p < 0.01), being Asian (OR 0.31; 95% CI, 0.17-0.56; p < 0.01), single or divorced marital status (OR 2.33; 95% CI, 1.47-3.68; p < 0.01), and more sleep per night (OR 1.92; 95% CI, 1.21-3.06; p < 0.01). Finally, single or divorced marital status was associated with drug use in the past year (OR 2.30; 95% CI, 1.26-4.18; p < 0.01). CONCLUSIONS: The lack of wellness among orthopaedic surgery residents is troubling, especially because most of the associated risk factors are potentially modifiable. Programs should capitalize on the modifiable elements to combat burnout and improve overall wellbeing. Programs should also educate residents on burnout, focus on work volume, protect access to health maintenance, nurture those in the early years of training, and remain acutely aware of the risk of substance abuse. Orthopaedic surgery trainees should strive to encourage peer support, cultivate personal responsibility, and advocate for themselves or peers when faced with challenges. At a minimum, programs and educational leaders should foster an environment in which admitting symptoms of burnout is not seen as a weakness or failure. LEVEL OF EVIDENCE: Level II, prognostic study.

Knee Arthrodesis Is a Durable Option for the Salvage of Infected Total Knee Arthroplasty.

BACKGROUND: Knee arthrodesis (KA) and above-knee amputation (AKA) have been used for salvage of failed total knee arthroplasty (TKA) after periprosthetic joint infection (PJI). However, few studies have assessed the outcomes of KA after TKA PJI, as it remains an uncommon procedure. We investigated rates of AKA, control of infection, and ambulatory status after KA for TKA PJI treatment. METHODS: This was a retrospective and single-surgeon series of 51 failed TKAs due to PJI treated with two-stage KA between 2000 and 2016 with a minimum of 2-year follow-up. Patient demographics, comorbidities, surgical history, radiographic data, and outcomes of KA treatment were recorded. RESULTS: Infection was successfully controlled in 48 of 51 patients (94.1%); of these, 24 knees (50.0%) required no reoperation subsequent to the index KA, whereas the remaining 24 (50.0%) patients required a median of 1 additional operation. Nonunion, malunion, or delayed union was noted in 10 patients (19.6%). Of the 48 patients who were successfully treated with KA, 41 patients (85.4%) remained ambulatory after KA and 9 of these patients (18.8%) did not require assistive devices. Three of 51 patients (5.9%) progressed to AKA after KA. CONCLUSION: Patients undergoing KA for TKA PJI had high rates of infection control and preservation of ambulatory status, with low rates of progression to AKA in our study. LEVEL OF EVIDENCE: Level IV-case series.

Improved Range of Motion and Patient-Reported Outcome Scores With Fixed-Bearing Revision Total Knee Arthroplasty for Suboptimal Axial Implant Rotation.

BACKGROUND: Suboptimal implant rotation has consequences with respect to knee kinematics and clinical outcomes. We evaluated the functional outcomes of revision total knee arthroplasty (TKA) for poor axial implant rotation. METHODS: We retrospectively reviewed 42 TKAs undergoing aseptic revision for poor axial implant rotation. We assessed improvements in Knee Society Score (KSS) and final range of motion (ROM). Subgroup analyses were performed for preoperative instability and stiffness, as well as the number of components revised and level of implant constraint used. RESULTS: Revision for poor axial rotation in isolation improved KSS from 52 ± 22 to 84 ± 25 (P < .001), and flexion increased from 105 ± 21° to 115 ± 13° (P = .001). Revision in the setting of instability significantly improved the KSS (P < .001) but did not affect ROM (P = .172). Revision in the setting of stiffness significantly improved both KSS (P < .001) and ROM (P = .002). There was no statistically significant difference between the postoperative KSS (P = .889) and final knee flexion (P = .629) with single- or both-component revision TKA for isolated poor axial rotation or between the postoperative KSS (P = .956) and final knee flexion (P = .541) with or without the use of higher constraint during revision TKA for isolated poor axial rotation. CONCLUSION: Revision TKA for poor axial alignment improves clinical outcomes scores and functional ROM.

Perioperative Dietary Restriction of Carbohydrates in the Management of Blood Glucose Levels in Patients Undergoing Total Knee Replacement.

BACKGROUND: Approximately 75% of the US population over 65 years has prediabetes or diabetes. Despite current evidence for the efficacy of carbohydrate restriction in managing blood glucose, this practice has not been implemented as part of routine perioperative blood sugar management. We hypothesize that a carbohydrate reduced hospital diet (CRD) of 135 g/d may improve blood sugar levels following total knee arthroplasty (TKA) compared to a non-carbohydrate reduced hospital diet (NCRD). METHODS: We randomized non-insulin-dependent prediabetic and diabetic patients undergoing TKA to either an NCRD or a CRD. Sixty-four patients were enrolled in the study and 2 were excluded, leading to 62 patients in the final analysis. The NCRD group included 14 females (47%) and 16 males (53%), with mean age of 68.5 years (±6.3 years). The CRD group included 16 females (50%) and 16 males (50%), with mean age of 68.0 years (±8.0 years). For hemoglobin A1C, the NCRD group had mean 5.8% (±0.6%) and the CRD group had mean 5.7% (±0.8%). For body mass index, the NCRD group had mean 29.3 kg/m2 (±6.3 kg/m2) and the CRD group 32.7 kg/m2 (±5.0 kg/m2). The primary outcome measure was mean blood glucose. RESULTS: Mean blood sugar values during hospital stay were significantly lower in the CRD group with 121.5 mg/dL (±17.1 mg/dL) compared to the NCRD group 141.2 mg/dL (±31.3 mg/dL, P = .0031). CONCLUSION: Blood sugar levels after surgery can be significantly reduced with a CRD. Further research is necessary to study the effect of reduced blood sugar levels on complications and infection rates following TKA surgery. LEVEL OF EVIDENCE: I.

Does the Watson-Jones or Modified Smith-Petersen Approach Provide Superior Exposure for Femoral Neck Fracture Fixation?

BACKGROUND: A well-reduced femoral neck fracture is more likely to heal than a poorly reduced one, and increasing the quality of the surgical exposure makes it easier to achieve anatomic fracture reduction. Two open approaches are in common use for femoral neck fractures, the modified Smith-Petersen and Watson-Jones; however, to our knowledge, the quality of exposure of the femoral neck exposure provided by each approach has not been investigated. QUESTIONS/PURPOSES: (1) What is the respective area of exposed femoral neck afforded by the Watson-Jones and modified Smith-Petersen approaches? (2) Is there a difference in the ability to visualize and/or palpate important anatomic landmarks provided by the Watson-Jones and modified Smith-Petersen approaches? METHODS: Ten fresh-frozen human pelvi underwent both modified Smith-Petersen (utilizing the caudal extent of the standard Smith-Petersen interval distal to the anterosuperior iliac spine and parallel to the palpable interval between the tensor fascia lata and the sartorius) and Watson-Jones approaches. Dissections were performed by three fellowship-trained orthopaedic traumatologists with extensive experience in both approaches. Exposure (in cm) was quantified with calibrated digital photographs and specialized software. Modified Smith-Petersen approaches were analyzed before and after rectus femoris tenotomy. The ability to visualize and palpate seven clinically relevant anatomic structures (the labrum, femoral head, subcapital femoral neck, basicervical femoral neck, greater trochanter, lesser trochanter, and medial femoral neck) was also recorded. The quantified area of the exposed proximal femur was utilized to compare which approach afforded the largest field of view of the femoral neck and articular surface for assessment of femoral neck fracture and associated femoral head injury. The ability to visualize and palpate surrounding structures was assessed so that we could better understand which approach afforded the ability to assess structures that are relevant to femoral neck fracture reduction and fixation. RESULTS: After controlling for age, body mass index, height, and sex, we found the modified Smith-Petersen approach provided a mean of 2.36 cm (95% confidence interval [CI], 0.45-4.28 cm; p = 0.015) additional exposure without rectus femoris tenotomy (p = 0.015) and 3.33 cm (95% CI, 1.42-5.24 cm; p = 0.001) additional exposure with a tenotomy compared with the Watson-Jones approach. The labrum, femoral head, subcapital femoral neck, basicervical femoral neck, and greater trochanter were reliably visible and palpable in both approaches. The lesser trochanter was palpable in all of the modified Smith-Petersen and none of the Watson-Jones approaches (p < 0.001). All modified Smith-Petersen approaches (10 of 10) provided visualization and palpation of the medial femoral neck, whereas visualization of the medial femoral neck was only possible in one of 10 Watson-Jones approaches (p < 0.001) and palpation was possible in eight of 10 Watson-Jones versus all 10 modified Smith-Petersen approaches (p = 0.470). CONCLUSIONS: In the hands of surgeons experienced with both surgical approaches to the femoral neck, the modified Smith-Petersen approach, with or without rectus femoris tenotomy, provides superior exposure of the femoral neck and articular surface as well as visualization and palpation of clinically relevant proximal femoral anatomic landmarks compared with the Watson-Jones approach. CLINICAL RELEVANCE: Open reduction and internal fixation of a femoral neck fracture is typically performed in a young patient (< 60 years old) with the objective of obtaining anatomic reduction that would not be possible by closed manipulation, thus enhancing healing potential. In the hands of surgeons experienced in both approaches, the modified Smith-Petersen approach offers improved direct access for reduction and fixation. Higher quality reductions and fixation are expected to translate to improved healing potential and outcomes. Although our experimental results are promising, further clinical studies are needed to verify if this larger exposure area imparts increased quality of reduction, healing, and improved outcomes compared with other approaches. The learning curve for the exposure is unclear, but the approach has broad applications and is frequently used in other subspecialties such as for direct anterior THA and pediatric septic hip drainage. Surgeons treating femoral neck fractures with open reduction and fixation should familiarize themselves with the modified Smith-Petersen approach.

Treatment of Periprosthetic Knee Infection With a Two-stage Protocol Using Static Spacers.

BACKGROUND: Two-stage exchange arthroplasty is a standard approach for treating total knee arthroplasty periprosthetic joint infection in the United States, but whether this should be performed with a static antibiotic spacer or an articulating one that allows range of motion before reimplantation remains controversial. It is unclear if the advantages of articulating spacers (easier surgical exposure during reimplantation and improved postoperative flexion) outweigh the disadvantages of increased cost and complexity in the setting of similar rates of infection eradication. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the ultimate range of motion; and (2) to determine the proportion of patients who remained free of infection at a minimum 2 years after treatment with static antibiotic spacers as part of a two-stage revision TKA for the treatment of periprosthetic joint infection. METHODS: Between 1999 and 2011, we treated 121 patients with chronically infected TKAs, of whom three had medical comorbidities precluding a two-stage exchange, four had died before 2-year followup for reasons other than the surgical intervention, and seven were lost to followup. The remaining 107 patients (109 knees; 53 men and 54 women) were treated using a two-stage approach with static spacers and are evaluated here at a mean of 3.7 years (range, 2.0-9.8 years); no patients were treated with articulating spacers during this study period. Twenty-five percent (27 of 109) of the organisms isolated the first-stage procedure were resistant to methicillin and/or vancomycin. Median age at the time of reimplantation was 67 years (range, 42-89 years). Range of motion was measured by an independent physical therapist with a standard goniometer. Knee Society knee and function scores were calculated before the first stage and at the 2-year mark. Because many of these patients were treated before consensus definitions of infection were established, we made the diagnosis of infection (and established that a patient was believed to be free of infection) using the approaches prevalent at that time, which generally included presence of a sinus tract communicating directly with the implant, two positive tissue cultures, or a combination of cultures, fluid analysis, and serology. RESULTS: Postoperatively, 67 knees had full extension and no patients had a flexion contracture > 10°. Median flexion was 100° (range, 60°-139°). Thirty-nine knees had postoperative flexion > 120°. Ninety-four percent of patients were clinically free of infection at last followup. CONCLUSIONS: Our two-stage exchange protocol with static spacers yielded comparable flexion and infection eradication when compared with other recent studies that have used articulating spacers. The large proportion of resistant organisms is alarming. Future multicenter studies should compare static with articulating spacers and should evaluate both cost and efficacy, because our study suggests that adequate range of motion can be achieved without the added cost of the articulating spacer. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Diagnosis of Periprosthetic Joint Infection: The Role of Nuclear Medicine May Be Overestimated.

Although the International Consensus Meeting on Periprosthetic Joint Infection's definition of periprosthetic joint infection (PJI) does not include nuclear imaging as part of the diagnostic criteria, many contemporary nuclear imaging studies are reporting exceptional results in PJI diagnosis. We conducted a systematic review of studies published from 2004 to 2012 reporting the accuracy of nuclear imaging for diagnosis of PJI, utilizing a specially designed tool (QUADAS-2) for critical appraisal and investigation of bias. Our results revealed high risk of bias as well as high levels of concern regarding the clinical applicability of these tests in a majority of the studies. On the basis of our findings, we recommend that the use of nuclear imaging for diagnosis of PJI be limited to a few select cases.

Medicare fails to compensate additional surgical time and effort associated with revision arthroplasty.

In comparison to primary total knee arthroplasty, surgical time was 1.8 times greater for all knee revisions and 2.4 times greater for complex knee revisions. Knee revisions had an 8.5% higher rate of 90-day repeat procedures. In comparison to primary total hip arthroplasty, surgical time was 1.8 greater for all hip revisions and 2.6 fold greater for complex hip revisions. Hip revisions had a 3.4% higher rate of 90-day repeat procedures. Practices based on revisions or complex revisions alone would see a 32% and 50% decrease in reimbursement respectively compared to the ones based on primary arthroplasty. The projected future increase in primary arthroplasties and the relative incentive to perform primary arthroplasty may soon put patient access to physicians willing to perform revision arthroplasty at risk.

What is the level of evidence substantiating the Medicare local coverage determinations?

Total joint arthroplasty (TJA) accounts for large expenditures of Medicare resources. Recovery audit contractors (RACs) utilize Local Coverage Determinations (LCDs) documents to retrospectively assess the medical necessity of performed procedures. The Florida LCD requires 3 months of documented unsuccessful nonoperative care prior to TJA. The purpose of our study was to evaluate the applicability and quality of the evidence cited in the Florida LCD for patients undergoing TJA. Applicability was assessed by evaluating the efficacy of nonoperative treatment in candidates for TJA. There were 23 citations, of which 11 mentioned nonoperative treatment and only 5 provided references. No citations provided Level I or II evidence substantiating the effectiveness of 3 months of nonoperative treatment in patients who would otherwise be candidates for TJA.

Diagnosis of periprosthetic joint infection in Medicare patients: multicriteria decision analysis.

BACKGROUND: In the setting of finite healthcare resources, developing cost-efficient strategies for periprosthetic joint infection (PJI) diagnosis is paramount. The current levels of knowledge allow for PJI diagnostic recommendations based on scientific evidence but do not consider the benefits, opportunities, costs, and risks of the different diagnostic alternatives. QUESTIONS/PURPOSES: We determined the best diagnostic strategy for knee and hip PJI in the ambulatory setting for Medicare patients, utilizing benefits, opportunities, costs, and risks evaluation through multicriteria decision analysis (MCDA). METHODS: The PJI diagnostic definition supported by the Musculoskeletal Infection Society was employed for the MCDA. Using a preclinical model, we evaluated three diagnostic strategies that can be conducted in a Medicare patient seen in the outpatient clinical setting complaining of a painful TKA or THA. Strategies were (1) screening with serum markers (erythrocyte sedimentation rate [ESR]/C-reactive protein [CRP]) followed by arthrocentesis in positive cases, (2) immediate arthrocentesis, and (3) serum markers requested simultaneously with arthrocentesis. MCDA was conducted through the analytic hierarchy process, comparing the diagnostic strategies in terms of benefits, opportunities, costs, and risks. RESULTS: Strategy 1 was the best alternative to diagnose knee PJI among Medicare patients (normalized value: 0.490), followed by Strategy 3 (normalized value: 0.403) and then Strategy 2 (normalized value: 0.106). The same ranking of alternatives was observed for the hip PJI model (normalized value: 0.487, 0.405, and 0.107, respectively). The sensitivity analysis found this sequence to be robust with respect to benefits, opportunities, and risks. However, if during the decision-making process, cost savings was given a priority of higher than 54%, the ranking for the preferred diagnostic strategy changed. CONCLUSIONS: After considering the benefits, opportunities, costs, and risks of the different available alternatives, our preclinical model supports the American Academy of Orthopaedic Surgeons recommendations regarding the use of serum markers (ESR/CRP) before arthrocentesis as the best diagnostic strategy for PJI among Medicare patients. LEVEL OF EVIDENCE: Level II, economic and decision analysis. See Instructions to Authors for a complete description of levels of evidence.

Revision knee arthroplasty for bone loss: choosing the right degree of constraint.

Revision total knee arthroplasty (TKA) in the setting of bone deficiency requires varied levels of constraint to restore knee stability. However, the outcomes between different levels remain controversial. Clinical outcomes for 183 AORI Type I knees, 168 Type II knees and 124 Type III knees utilizing posterior stabilized (PS), unlinked constrained (UC) or hinged prostheses were evaluated with standardized clinical assessment tools and radiographic results over an average of 7.4 years. PS yielded superior knee scores in AORI Type I patients (P<0.05), UC in Type II and III aseptic patients (P<0.05), and a hinge was preferred in septic Type II or III knees (P<0.05). Revision TKA conducted with increased constraint appears effective in the setting of increased bone deficiency.

Why are total knee arthroplasties failing today--has anything changed after 10 years?

The purpose of this study was to determine the frequency and cause of failure after total knee arthroplasty and compare the results with those reported by our similar investigation conducted 10 years ago. A total of 781 revision TKAs performed at our institution over the past 10 years were identified. The most common failure mechanisms were: loosening (39.9%), infection (27.4%), instability (7.5%), periprosthetic fracture (4.7%), and arthrofibrosis (4.5%). Infection was the most common failure mechanism for early revision (<2 years from primary) and aseptic loosening was the most common reason for late revision. Polyethylene (PE) wear was no longer the major cause of failure. Compared to our previous report, the percentage of revisions performed for polyethylene wear, instability, arthrofibrosis, malalignment and extensor mechanism deficiency has decreased.

Extensor mechanism reconstruction with achilles tendon allograft in TKA: results of an abbreviate rehabilitation protocol.

Various treatment alternatives address extensor mechanism failure after total knee arthroplasty. We present the results of a protocol utilizing Achilles tendon allograft followed by an abbreviated immobilization program to treat extensor mechanism disruptions after TKA in 29 knees (27 patients). Failed reconstruction was defined as mechanical allograft failure requiring re-intervention, extension lag >30°, recurrent falls, regression to a lower ambulatory status, and revision due to infection. With mean follow-up of 3.5 years, seventeen cases (58.6%) had satisfactory results, eleven cases (37.9%) were considered failures, and one case was lost to follow-up. Among failures, eight (27.5%) underwent reoperation with four (13.8%) due to late infections. Our observational data suggest that 1) a shortened immobilization protocol yields less favorable results than expected, and 2) continuous monitoring of patients who had allograft reconstruction for possible development of late infection is recommended.

Pattern of impact of femoroacetabular impingement upon health-related quality of life: the determinant role of extra-articular factors.

PURPOSE: Despite the interest in surgical treatment of femoroacetabular impingement (FAI), its impact upon health-related quality of life (HRQoL) has not been established. The objectives of this study were twofold: (a) to describe the pattern of impact of FAI on HRQoL and (b) to assess how articular and extra-articular factors influence HRQoL in this group of patients. METHODS: A total of 108 patients [55 females (50.9 %); age 36.0 ± 12.4 years] with intraoperatively confirmed FAI and no evidence of secondary hip osteoarthritis were studied. The pattern of impact on HRQoL was studied using SF-36 V.2™ and then contrasted with other medical conditions employing the SF-36 spydergram. The best model explaining the influence of "articular" and "extra-articular" factors over the SF-36 physical and mental component scores (PCS/MCS) was selected using the Akaike information criterion. RESULTS: The PCS was 53.2 ± 19.2 and MCS was 68.94 ± 17.15. The SF-36 spydergram depicted an impact pattern distinguishable from other conditions. A linear model predicted PCS would increase by 8.9 points in male patients and 3.7 points per point of University of California Los Angeles score (p value <0.01; R2 0.29). For MCS, obesity resulted in a 12.7 point reduction, psychiatric comorbidity reduced it by 11.1; and a combined reduction of 19 points (p value <0.01; R2 0.18). Unexpectedly, the extent of intra-articular disease had no influence on PCS or MCS. CONCLUSIONS: FAI impacts HRQoL with a distinguishable pattern. In our study, the manner in which HRQoL is affected by FAI can be explained only by patients' characteristics unrelated to the extent of intra-articular disease. LEVEL OF EVIDENCE: Prognostic Level IV.