Implementation of the New Medicare-Mandated Patient-Reported Outcomes After Joint Arthroplasty Performance Measure.

A new mandatory hospital-level, risk-standardized performance measure for elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) based on patient-reported outcomes (THA/TKA PRO-PM) has been implemented by the Centers for Medicare & Medicaid Services (CMS). All THA and TKA in Medicare fee-for-service beneficiaries at inpatient facilities are included. The THA/TKA PRO-PM is the proportion of risk-standardized THA or TKA patients meeting or exceeding the substantial clinical benefit threshold between preoperative and postoperative outcomes measures (Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement, Knee injury and Osteoarthritis Outcome Score for Joint Replacement). This binary outcome (yes/no) is then divided by all eligible patients creating a percentage of patients reaching substantial clinical benefit. The percentile score among hospitals will be reported. Following 2 voluntary reporting periods, mandatory reporting will begin in 2025. The CMS requires 50% reporting rates; failure leads to annual payment reduction in fiscal year 2028. The CMS intends the THA/TKA PRO-PM to be a patient-centered, meaningful, and relatable measure of hospital performance reported to the public. For surgeons, this is an opportunity to collaborate with hospitals for developing and implementing a THA/TKA data collection system to avoid penalties for the hospital. Further implementation for outpatient surgery and in ambulatory surgery centers has been announced by CMS. Major resources will be needed to succeed in the expected capture rates.

Oxidized Zirconium Versus Cobalt Chromium for Primary TKA: No Difference in Midterm Revision Rates From the American Joint Replacement Registry.

BACKGROUND: Cobalt chromium (CoCr) is the most commonly used material in TKA; however, the use of oxidized zirconium (OxZr) implants has increased. The advantages to this material demonstrated in basic science studies have not been borne out in clinical studies to date. QUESTION/PURPOSE: In the setting of the American Joint Replacement Registry (AJRR), how do revision rates differ between CoCr and OxZr after primary TKA? METHODS: The AJRR was accessed for all primary TKAs performed between 2012 and 2020 for osteoarthritis, resulting in 441,605 procedures (68,506 with OxZr and 373,099 with CoCr). The AJRR is the largest joint replacement registry worldwide and collects procedure-specific details, making it ideal for large-scale comparisons of implant materials in the United States. Competing risk survival analyses were used to evaluate the all-cause revision rates of primary TKAs, comparing CoCr and OxZr implants. Data from the Centers for Medicare and Medicaid Services claims from 2012 to 2017 were also cross-referenced to capture additional revisions from other institutions. Revision rates were tabulated and subclassified by indication. Multivariate Cox regression was used to account for confounding variables such as age, gender, region, and hospital size. RESULTS: After controlling for confounding variables, there were no differences between the OxZr and CoCr groups in terms of the rate of all-cause revision at a mean follow-up of 46 ± 23 months and 44 ± 24 months for CoCr and OxZr implants, respectively (hazard ratio 1.055 [95% confidence interval 0.979 to 1.137]; p = 0.16) The univariate analysis demonstrated increased rates of revisions for pain and instability in the OxZr group (p = 0.003 and p < 0.001, respectively). CONCLUSION: These findings suggest there is no difference in all-cause revision between OxZr and CoCr implants in the short-term to mid-term. However, further long-term in vivo studies are needed to monitor the safety and all-cause revision rate of OxZr implants compared with those of CoCr implants. OxZr implants may be favorable in patients who have sensitivity to metal. Despite similar short-term to mid-term all-cause revision rates to CoCr implants, because of the limitations of this study, definitive recommendations for or against the use of OxZr cannot be made. LEVEL OF EVIDENCE: Level III, therapeutic study.

Reasons and Risk Factors for Failed Same-Day Discharge After Total Joint Arthroplasty.

BACKGROUND: A shift toward same-day discharge (SDD) in primary elective total knee arthroplasty (TKA) and total hip arthroplasty (THA) has created a need to optimize patient selection and improve same-day recovery pathways. The objectives of this study were (1) to identify our institution's most common causes for failed SDD, and (2) to evaluate risk factors associated with failed SDD. METHODS: A retrospective review of SDD patients undergoing primary TKA or THA from January 2021 to September 2022 was conducted. Reasons for SDD failure were recorded and differences between successful and failed SDD cases were assessed via a multivariate logistic regression. RESULTS: Overall, 85.3% (651 of 753) of patients included were successful SDDs. Failed SDD occurred in 16.8% (74 of 441) of TKA and 11.8% (38 of 322) of THA cases. Primary reasons included failure to clear physical therapy (33.0%, 37 of 112), postoperative hypotension (20.5%, 23 of 112), and urinary retention (16.9%, 19 of 112). Analysis revealed that overall failed SDD cases were more likely to have had prior opioid use and a longer surgical time. Failed TKA SDD cases were more likely to have had a longer surgical time and not have receive a preoperative nerve block, while failed THA SDD cases were more likely to be older. CONCLUSIONS: The SDD selection criteria and pathways continue to evolve, with multiple factors contributing to failed SDD. Improving patient selection algorithms and optimizing post-operative pathways can enhance the ability to successfully choose SDD candidates. LEVEL OF EVIDENCE: III.

An Innovative Seven-year Physician Scientist Residency Training Program That Addresses the Shortage of Academic Surgeons.

Due to the declining number of scientifically trained physicians and increasing demand for high-quality literature, our institution pioneered a seven-year Physician Scientist Training Program (PSTP) to provide research-oriented residents the knowledge and skills for a successful academic career. The present study sought to identify orthopaedic surgeons with MD/PhD degrees, residency programs with dedicated research tracks, and to assess the effectiveness of the novel seven-year program in training prospective academic orthopaedic surgeons. Surgeons with MD/PhD degrees account for 2.3% of all 3,408 orthopaedic faculty positions in U.S. residency programs. During the last 23 years, our PSTP residents produced 752 peer-reviewed publications and received $349,354 from 23 resident-authored extramural grants. Eleven of our seven-year alumni practice orthopaedic surgery in an academic setting. The seven-year PSTP successfully develops clinically trained surgeon scientists with refined skills in basic science and clinical experimental design, grant proposals, scientific presentations, and manuscript preparation. (Journal of Surgical Orthopaedic Advances 31(3):144-149, 2022).

A Case Complexity Modifier Is Warranted for Primary Total Knee Arthroplasty.

BACKGROUND: The Center for Medicare and Medicaid Services is faced with a challenge of decreasing the cost of care for total knee arthroplasty (TKA) but must make efforts to prevent patient selection bias in the process. Currently, no appropriate modifier codes exist for primary TKA based on case complexity. We sought to determine differences in perioperative parameters for patients with complex primary TKA with the hypothesis that they would require increased cost of care, prolonged care times, and have worse postoperative outcome metrics. METHODS: We performed a single-center retrospective review from 2015 to 2018 of all primary TKAs. Patient demographics, medial proximal tibial angle (mPTA), lateral distal femoral angle (lDFA), flexion contracture, cost of care, and early postoperative outcomes were collected. Complex patients were defined as those requiring stems or augments, and multivariable logistic regression analysis and propensity score matching were performed to evaluate perioperative outcomes. RESULTS: About 1043 primary TKAs were studied, and 84 patients (8.3%) were deemed complex. For this cohort, surgery duration was greater (P < .001), cost of care higher (P < .001), and patients had a greater likelihood for 90-day hospital return. Deviation of mPTA and lDFA was significantly greater preoperatively before and after propensity score matching. Cut point analysis demonstrated that preoperative mPTA <83o or >91o, lDFA <84o or >90o, flexion contracture >10o, and body mass index >35.7 were associated with complex procedures. CONCLUSION: Complex primary TKA may be identifiable preoperatively and those cases associated with prolonged operative time, excess hospital cost of care, and increased 90-day hospital returns. This should be considered in future reimbursement models to prevent patient selection bias, and a complexity modifier is warranted.

Complications and Costs Are Not Increased After Total Hip Arthroplasty in Patients With a History of Prostate Cancer.

BACKGROUND: Prostate cancer (PCa) is a largely prevalent disease in the United States. Moreover, it is unclear whether the thromboembolic burden of disease remains present after the cancer has been treated and whether such state impacts the short-term outcomes of orthopedic procedures. Therefore, the purpose of this study is to assess 90-day postoperative complications and costs after total hip arthroplasty (THA) for osteoarthritis in patients with a history of PCa. METHODS: Two groups of patients who underwent THA for osteoarthritis in the Medicare Standard Analytical Files were identified through the PearlDiver server. Both groups were matched based on age, diabetes, smoking status, chronic kidney disease, alcohol abuse, chronic liver disease, and obesity in order to create a case-control study comparison. The 90-day complication rates after THA were compared using univariate regressions (odds ratio). We hypothesized that patients with a history of PCa would develop increased rates of thromboembolic complications based on a prolonged procoagulative state. RESULTS: After matching, each group was comprised of 62,571 patients. Our findings identified greater 90-day pneumonia rates for those without a history of PCa (3.26% vs 2.68%; odds ratio, 0.82). All other complications including thromboembolic diseases were clinically comparable in both groups during the 90-day postoperative period. The charges and reimbursements for the 90-day period were also comparable. CONCLUSION: In our large case-control study of 125,142 patients, we found that patients with a history of PCa do not have increased risk of short-term complications after THA and that the mean 90-day reimbursements were similar for both groups at $14,153 for PCa patients and $14,033 for those without (P = .114).

Value-Based Care Has Not Resulted in Biased Patient Selection: Analysis of a Single Center's Experience in the Care for Joint Replacement Bundle.

BACKGROUND: Bundled reimbursement models for total knee arthroplasty (TKA) by the Center for Medicare and Medicaid Services have resulted in an effort to decrease the cost of care. However, these models may incentivize bias in patient selection to avoid excess cost of care. We sought to determine the impact of the Comprehensive Care for Joint Replacement (CJR) model at a single center. METHODS: This is a retrospective review of primary TKA patients from July 2015 to December 2017. Patients were stratified by whether or not their surgery was performed before or after implementation of the CJR bundle. Patient demographic data including age, sex, and body mass index were collected in addition to Elixhauser comorbidities and American Society of Anesthesiologists score. In-hospital outcomes were then examined including surgery duration, length of stay, discharge disposition, and direct cost of care. RESULTS: A total of 1248 TKA patients (546 Medicare and 702 commercial insurance) were evaluated, with 27.0% undergoing surgery before the start of the bundle. Compared to patients following implementation of the bundle, there was no significant difference in age, gender, or body mass index. However, pre-CJR Medicare patients were more likely to have fewer Elixhauser comorbidities (P < .001), prolonged length of stay (P < .001), and greater discharges to inpatient facilities (P = .019). There was no significant difference in direct hospital costs or operative service time comparing pre-bundle and post-bundle patients. CONCLUSION: Implementation of the bundled reimbursement model did not result in biased patient selection at our institution; importantly, it also did not result in decreased hospital costs despite apparent improvement in value-based outcome metrics. This should be taken into consideration as future adaptations to reimbursement are made by the Center for Medicare and Medicaid Services.

Utilization of an Electronic Patient Portal Following Total Joint Arthroplasty Does Not Decrease Readmissions.

BACKGROUND: At the investigating institution, an electronic messaging portal (MyChart) allows patients to directly communicate with their healthcare provider. As reimbursement models evolve, there is an increasing effort to decrease 90-day hospital resource utilization and patient returns, and secure messaging portals have been proposed as one way to achieve this goal. We sought to determine which patients utilize this portal, and to determine the impact of secure messaging on emergency department (ED) visits and readmissions within 90 days postoperatively. METHODS: The institutional database was used to analyze 6426 procedures including 3297 primary total knee and 3129 primary total hip arthroplasties. Patient demographics, comorbidities, and secure communication activity status were recorded. Subsequently, statistical analysis was performed to determine which patients utilized MyChart, as well as to correlate patient outcomes to the utilization of secure messaging portals. RESULTS: Active MyChart users were significantly more likely to be young, healthy (American Society of Anesthesiologists 1 or 2), Caucasian, married, employed, have private insurance, and be discharged to home. Decreased utilization was seen in patients who were unhealthy (American Society of Anesthesiologists 3 or 4), were African American, unmarried, unemployed, had Medicare or Medicaid insurance, and were discharged to a skilled nursing facility; these characteristics were also independent significant risks for returning to the ED. Active MyChart status was not significantly associated with 90-day ED return (P = .781) or readmission (P = .512). However, if multiple messages to providers were sent, and the provider response rate was <75%, patients had significantly more readmissions (P = .004). CONCLUSION: Primary total joint arthroplasty patients who were at high risk for ED returns were less likely to utilize MyChart. However, MyChart use did not decrease the 90-day rate of return to the ED or readmissions. A low provider response rate to the secure messages may lead to increased resource utilization in patients using secure messaging as their preferred communication tool. Alternative means of communication with the most vulnerable patients must be investigated to effectively decrease postoperative complications and resource utilization.

Medicaid Insurance Correlates With Increased Resource Utilization Following Total Hip Arthroplasty.

BACKGROUND: With increased restraints and efforts to contain costs in total hip arthroplasty (THA), an emphasis has been placed on risk stratification. The purpose of this study was to determine whether Medicaid patients have increased resource utilization (including 90-day emergency department [ED] visits and readmissions) compared to Medicare or commercial insurance carriers. The study hypothesized that the Medicaid population would represent a high-risk cohort with increased resource utilization. METHODS: The institutional database was retrospectively queried for primary THAs from 2013 to 2017 based on Current Procedural Terminology codes and patients undergoing revision surgery were excluded. Demographic information including age, sex, and body mass index (BMI) and medical comorbidities including American Society of Anesthesiologists (ASA) scores were evaluated. Patients were stratified by insurance type and length of stay (LOS), and 90-day ED visits and 90-day readmissions were assessed in univariable and multivariable analysis. RESULTS: A total of 3674 primary THA patients were included in the analysis (including 116 with Medicaid, 1713 with Medicare, and 1845 with other insurance providers). Medicaid patients had significantly higher ASA scores (P < .001) and BMI (P < .001), with corresponding increase in procedure duration (115 vs 99 vs 105 minutes; P < .001). They had a prolonged LOS (2.5 vs 2.5 vs 1.5 days; P < .001) compared with other insurances, but similar to Medicare patients. Following discharge, in multivariable analysis controlling for age, BMI, and ASA score, Medicare patients were significantly more likely to return to the ED (odds ratio, 3.15; 95% confidence interval, 1.88-5.27; P < .001) and be readmitted (odds ratio, 2.46; 95% confidence interval, 1.26-4.81; P = .009). CONCLUSION: Medicaid patients represent a higher risk cohort with increased resource utilization perioperatively, including longer LOS, and more 90-day ED visits and readmissions. This should be considered in outcome assessments and alternative expectations for the episode of care should be set for this population.

Should Medical Severity-Diagnosis Related Group Classification Be Utilized for Reimbursement? An Analysis of Elixhauser Comorbidities and Cost of Care.

BACKGROUND: The Center for Medicare and Medicaid Services (CMS) classifies reimbursement for total hip arthroplasty (THA) and total knee arthroplasty (TKA) based on Medical Severity-Diagnosis Related Groups (MS-DRGs) 469 (with major complication/comorbidity) and 470 (without major complication/comorbidity). The validated Elixhauser comorbidity index includes 31 variables that may be associated with MS-DRG 469. However, we hypothesized that these comorbidities may not be the most predictive of increased cost of care. METHODS: Elixhauser comorbidities were retrospectively examined for 1243 TKAs and 897 THAs from 2013 to 2017 at a single center. Comorbidities were investigated in univariable analysis and significant variables associated with MS-DRG 469, and cost of care was further investigated in a multivariable regression to determine which were most predictive of the increased complexity classification assigned by CMS vs true increased cost of care. RESULTS: Thirty-nine patients (1.8%) were classified as MS-DRG 469. Univariable and multivariable logistic analysis revealed that coagulopathy, electrolyte disorders, neurodegenerative disorders, and psychosis were significantly associated with an increased complexity classification. These 4 comorbidities were also associated with increased cost of care; however, 13 additional comorbidities were also predictive of increased cost but not MS-DRG classification. CONCLUSIONS: Patient comorbidities have been shown to increase complications and cost of care for arthroplasty patients. To date, however, the only risk adjustment provided has been the 469 DRG code. This study demonstrates little correlation to the current system with the most expensive diagnoses. Consequently, an expansion of the current risk adjustment system for THA and TKA provided by CMS appears greatly needed.

No Changes in Patient Selection and Value-Based Metrics for Total Hip Arthroplasty After Comprehensive Care for Joint Replacement Bundle Implementation at a Single Center.

BACKGROUND: Alternative payment models for total hip arthroplasty (THA) were initiated by the Center for Medicare and Medicaid Services to decrease overall healthcare cost. The associated shift of financial risk to participating institutions may negatively influence patient selection to avoid high cost of care ("cherry picking," "lemon dropping"). This study evaluated the impact of the Comprehensive Care for Joint Replacement (CJR) model on patient selection, care delivery, and hospital costs at a single care center. METHODS: Patients undergoing a primary THA from 2015-2017 were stratified by insurance type (Medicare and commercial insurance) and whether care was provided before (pre-CJR) or after (post-CJR) CJR bundle implementation. Patient age, gender, and body mass index, Elixhauser comorbidities and American Society of Anesthesiologists scores, were analyzed. Delivery of care variables including surgery duration, discharge disposition, length of stay, and direct hospital costs were compared pre- and post-CJR. RESULTS: A total of 751 THA patients (273 Medicare and 478 commercial Insurance) were evaluated pre-CJR (29%) and post-CJR (71%). Patient demographics were similar (age, gender, BMI); however, commercially insured patients had less comorbidities pre-CJR (P = .033). Medicare patient post-CJR length of stay (P = .010) was reduced with a trend toward discharge to home (P = .019). Surgical time, operating room service time, 90-day readmissions and direct hospital costs were similar pre- and post-CJR. CONCLUSION: There was no differential patient selection after CJR bundle implementation and value-based metrics (surgical time, operating room service time) were not affected. Patients were discharged sooner and more often to home. However, overall direct hospital expenses remained unchanged revealing that any cost savings were for insurance providers, not participating hospitals.

Decreased Time to Return to Work Using Robotic-Assisted Unicompartmental Knee Arthroplasty Compared to Conventional Techniques.

INTRODUCTION: Unicompartmental knee arthroplasty (UKA) is a commonly used procedure for patients suffering from debilitating unicompartmental knee arthritis. For UKA recipients, robotic-assisted surgery has served as an aid in improving surgical accuracy and precision. While studies exist detailing outcomes of robotic UKA, to our knowledge, there are no studies assessing time to return to work using robotic-assisted UKA. Thus, the purpose of this study was to prospectively assess the time to return to work and to achieve the level of work activity following robotic-assisted UKA to create recommendations for patients preoperatively. We hypothesized that the return to work time would be shorter for robotic-assisted UKAs compared with TKAs and manual UKAs, due to more accurate ligament balancing and precise implementation of the operative plan. MATERIALS AND METHODS: Thirty consecutive patients scheduled to undergo a robotic-assisted UKA at an academic teaching hospital were prospectively enrolled in the study. Inclusion criteria included employment at the time of surgery, with the intent on returning to the same occupation following surgery and having end-stage knee degenerative joint disease (DJD) limited to the medial compartment. Patients were contacted via email, letter, or phone at two, four, six, and 12 weeks following surgery until they returned to work. The Baecke physical activity questionnaire (BQ) was administered to assess patients' level of activity at work pre- and postoperatively. Statistical analysis was performed using SAS Enterprise Guide (SAS Institute Inc., Cary, North Carolina) and Excel® (Microsoft Corporation, Redmond, Washington). Descriptive statistics were calculated to assess the demographics of the patient population. Boxplots were generated using an Excel® spreadsheet to visualize the BQ scores and a two-tailed t-test was used to assess for differences between pre- and postoperative scores with alpha 0.05. RESULTS: The mean time to return to work was 6.4 weeks (SD=3.4, range 2-12 weeks), with a median time of six weeks. There was no difference seen in the mean pre- and postoperative BQ scores (2.70 vs. 2.69, respectively; p=0.87). CONCLUSION: The findings of the current study suggest that most patients can return to work six weeks following robotic-assisted UKA which appears to be shorter than conventional UKA and TKA. Future level I studies are needed to verify our study findings.

Impact of Fluoroscopically Guided Bone Biopsy on Antibiotic Management of Osteomyelitis in the Lower Extremity.

This study evaluated the impact of fluoroscopically guided percutaneous bone biopsy on altering antibiotic regimens in lower extremity osteomyelitis. Eighty-eight patients who received fluoroscopically guided bone biopsies were identified. There was bacterial growth in 28% of bone biopsies overall. The rate of positive culture was decreased in patients started on empiric antibiotics before biopsy (23%) compare with patients without empiric antibiotics (44%). Antibiotic regimens were changed in 24% of patients overall in response to culture data. The majority of positive biopsy cultures (76%) but minority of negative biopsy cultures (3%) resulted in a change to antibiotic regimens. The impact of percutaneous bone biopsy on antibiotic management of adult patients with osteomyelitis diagnosed by magnetic resonance imaging is modest and is decreased in patients previously started on antibiotics. Despite its modest impact, bone biopsy results can provide useful information in antibiotic management, especially when positive (Journal of Surgical Orthopaedic Advances 27(4):277-280, 2018).

The Development of a Xenograft-Derived Scaffold for Tendon and Ligament Reconstruction Using a Decellularization and Oxidation Protocol.

PURPOSE: To evaluate the biological, immunological, and biomechanical properties of a scaffold derived by architectural modification of a fresh-frozen porcine patella tendon using a decellularization protocol that combines physical, chemical, and enzymatic modalities. METHODS: Porcine patellar tendons were processed using a decellularization and oxidation protocol that combines physical, chemical, and enzymatic modalities. Scaffolds (n = 88) were compared with native tendons (n = 70) using histologic, structural (scanning electron microscopy, porosimetry, and tensile testing), biochemical (mass spectrometry, peracetic acid reduction, DNA quantification, alpha-galactosidase [α-gal] content), as well as in vitro immunologic (cytocompatibility, cytokine induction) and in vivo immunologic nonhuman primate analyses. RESULTS: A decrease in cellularity based on histology and a significant decrease in DNA content were observed in the scaffolds compared with the native tendon (P < .001). Porosity and pore size were increased significantly (P < .001). Scaffolds were cytocompatible in vitro. There was no difference between native tendons and scaffolds when comparing ultimate tensile load, stiffness, and elastic modulus. The α-gal xenoantigen level was significantly lower in the decellularized scaffold group compared with fresh-frozen, nondecellularized tissue (P < .001). The in vivo immunological response to implanted scaffolds measured by tumor necrosis factor-α and interleukin-6 levels was significantly (P < .001) reduced compared with untreated controls in vitro. These results were confirmed by an attenuated response to scaffolds in vivo after implantation in a nonhuman primate model. CONCLUSIONS: Porcine tendon was processed via a method of decellularization and oxidation to produce a scaffold that possessed significantly less inflammatory potential than a native tendon, was biocompatible in vitro, of increased porosity, and with significantly reduced amounts of α-gal epitope while retaining tensile properties. CLINICAL RELEVANCE: Porcine-derived scaffolds may provide a readily available source of material for musculoskeletal reconstruction and repair while eliminating concerns regarding disease transmission and the morbidity of autologous harvest.

Obesity has no effect on outcomes following unicompartmental knee arthroplasty.

PURPOSE: Although obesity has historically been described as a contraindication to UKA, improved outcomes with modern UKA implant designs have challenged this perception. The purpose of this study was to assess the influence of obesity on the outcomes of UKA with a robotic-assisted system at a minimum follow-up of 24 months with the hypothesis that obesity has no effect on robotic-assisted UKA outcomes. METHODS: There were 746 medial robotic-assisted UKAs (672 patients) with a mean age of 64 years (SD 11) and a mean follow-up time of 34.6 months (SD 7.8). Mean overall body mass index (BMI) was 32.1 kg/m2 (SD 6.5), and patients were stratified into seven weight categories according to the World Health Organization classification. RESULTS: Patient BMI did not influence the rate of revision surgery to TKA (5.8 %) or conversion from InLay to OnLay design (1.7 %, n.s.). Mean postoperative Oxford knee score was 37 (SD 11) without correlation with BMI (n.s.). The type of prosthesis (InLay/OnLay) regardless of BMI had no influence on revision rate (n.s.). BMI did not influence 90-day readmissions (4.4 %, n.s.), but showed significant correlation with higher opioid medication requirements and a higher number of physical therapy session needed to reach discharge goals (p = 0.031). CONCLUSION: These findings suggest that BMI does not influence clinical outcomes and readmission rates of robotic-assisted UKA at mid-term. The classic contraindication of BMI >30 kg/m2 may not be justified with the use of modern UKA designs or techniques. LEVEL OF EVIDENCE: IV.

Cost Analysis of Sending Routine Pathology Specimens following Total Joint Arthroplasty in the Age of Bundled Payments.

Bundled payment plans are being developed as a means to curb healthcare spending. Routine histology following total hip arthroplasties (THA) and total knee arthroplasties (TKA) is standard practice at many institutions. Recently, the value of this practice has been questioned as histologic diagnoses in THA and TKA rarely differ from the clinical diagnoses. The goal of this study is to identify discrepant and discordant diagnoses following THA and TKA at an academic medical center and to calculate the cost-saving potential in the setting of a bundled payment plan. A retrospective chart review was conducted on 1,213 primary THA and TKA performed by two orthopaedic surgeons from 2012 to 2014. The clinical and histologic diagnoses were compared and classified as concordant, discrepant, or discordant. Cost information was obtained from the institutional billing office. One thousand one hundred and sixty-six THA and TKA were analyzed in the final cohort. Nineteen (1.6%) diagnoses were classified as discrepant while none were discordant. The cost of histologic examination per specimen was estimated to be $48.56. The total cost of all arthroplasties was $14,999,512.46, of which histologic examination made up 0.31% of the total cost. The results of this study corroborate the results of previous studies and support the proposition that routine histologic examination is not cost-effective. The cost incurred to perform histologic examination will become a cost deduction from future bundled payments. The practice of sending routine histologic specimens following TJA should be decided upon by the operating orthopaedic surgeon.

Patient Factors and Cost Associated with 90-Day Readmission Following Total Hip Arthroplasty.

This study sought to identify specific costs for 90-day readmissions following total hip arthroplasty in a bundled payment system. Hospital billing records revealed 139 readmissions (8.93%) in 1781 patients. Mean costs for surgical readmissions were greater (P=0.002) compared with medical reasons, but similar for Medicare/Medicaid and private payers (P=0.975). Costs for imaging, laboratory workup, medication and transfusions, and hospital cost correlated with increasing SOI (P<0.05). Patients transferred from outside hospitals or rehabilitation had higher hospital (P=0.006) and operating room costs (P=0.001) compared to patients admitted from ED or clinic. Hospitals that care for complex patients with Medicare/Medicaid may experience increased costs for unplanned 90-day readmissions highlighting considerations for payer mix.

Decreased Range of Motion After Total Knee Arthroplasty Is Predicted by the Tampa Scale of Kinesiophobia.

BACKGROUND: Range of motion (ROM) is important for functional outcome after total knee arthroplasty (TKA); however, some patients hesitate to maximize their ROM postoperatively. The Tampa Scale of Kinesiophobia (TSK) measures patients' fear of movement. The primary purpose of this investigation was to determine whether TSK scores correlated with decreased ROM after primary TKA. A secondary purpose was to determine whether biofeedback could increase ROM after TKA. METHODS: Patients were recruited from the senior author's practice between June 2011 and March 2013. A clinical photograph was taken of each patient's knee in maximum passive flexion in the operating room immediately following closure. Patients were randomized to the control or photograph group before incision. A linear mixed model was implemented to determine whether the TSK score and viewing the photo correlated to ROM. RESULTS: Seventy-nine patients were analyzed for correlation between the TSK score and the knee ROM. Sixty patients were analyzed for correlation between viewing the clinical photograph and the knee ROM. The linear mixed model demonstrated a significant negative correlation between the TSK score and both active (ß = -0.47, P < .01) and passive (ß = -0.66, P < .001) knee flexions. There was a trend toward decreased knee flexion among patients shown their clinical photograph. CONCLUSION: The TSK was developed as a tool to identify patients at risk for maladaptive responses to painful stimuli. Our data suggest that the TSK may help arthroplasty surgeons identify patients at risk for decreased ROM after TKA. Showing patients a clinical photograph failed to increase ROM after TKA.

Factors Associated with Range of Motion Recovery Following Manipulation Under Anesthesia.

INTRODUCTION: Stiffness and loss of motion following total knee arthroplasty (TKA) is a complex and multifactorial complication that may require manipulation under anesthesia (MUA). However, patient and surgical factors that potentially influence the development of knee stiffness following TKA are not fully understood. The purpose of this study was to identify patient and surgical factors that may influence range of motion loss following TKA by assessing a cohort of patients that underwent MUA and comparing them to a matched cohort of patients without complications. MATERIALS AND METHODS: The joints registry was searched for patients who underwent MUA following primary TKA between 2004 and 2013. Demographic and surgical information was obtained from the electronic medical record including range of motion (ROM), comorbidities and timing of MUA. Patients who underwent MUA were then double-matched by baseline (prior to primary TKA) knee ROM to patients who underwent primary TKA with normal postoperative range of motion recovery during the same time period. RESULTS: Fifty-two patients (fifty-six knees) (66% female, mean BMI 32.4 kg/m2) underwent MUA after TKA during the study period. MUA was performed a mean of 13.6 weeks after primary TKA. Study patients were double-matched by baseline flexion (mean 107º±2º) to 111 patients (112 knees) with a similar mean baseline flexion (104º±2º, p=0.138). Patients requiring MUA were younger (mean age 56 vs. 64 years, p<0.001), had more comorbidities (5 vs. 3, p<0.001), and a higher number of previous knee surgeries (56% vs. 21%, p<0.001) compared with controls. The risk for requiring MUA following primary TKA was significantly higher (2.4, p<0.001) in patients with previous knee surgery (arthroscopy for meniscal pathology, ACL reconstruction, osteotomies). Tourniquet time, length of stay, number of physical therapy sessions, blood loss >50 mL, and any complication during the hospital stay were not found to be associated with an increased risk of requiring MUA. CONCLUSION: Younger patients with more comorbidities and a history of previous knee surgery were found to have significantly higher risk for developing stiffness and loss of motion requiring MUA after primary TKA in the current study. Patients with this risk profile need to be counseled regarding the risk for postoperative knee stiffness and range of motion loss possibly requiring MUA after primary TKA.

Multiple Small Diameter Drillings Increase Femoral Neck Stability Compared with Single Large Diameter Femoral Head Core Decompression Technique for Avascular Necrosis of the Femoral Head.

Femoral head core decompression is an efficacious joint-preserving procedure for treatment of early stage avascular necrosis. However, postoperative fractures have been described which may be related to the decompression technique used. Femoral head decompressions were performed on 12 matched human cadaveric femora comparing large 8mm single bore versus multiple 3mm small drilling techniques. Ultimate failure strength of the femora was tested using a servo-hydraulic material testing system. Ultimate load to failure was compared between the different decompression techniques using two paired ANCOVA linear regression models. Prior to biomechanical testing and after the intervention, volumetric bone mineral density was determined using quantitative computed tomography to account for variation between cadaveric samples and to assess the amount of bone disruption by the core decompression. Core decompression, using the small diameter bore and multiple drilling technique, withstood significantly greater load prior to failure compared with the single large bore technique after adjustment for bone mineral density (p< 0.05). The 8mm single bore technique removed a significantly larger volume of bone compared to the 3mm multiple drilling technique (p< 0.001). However, total fracture energy was similar between the two core decompression techniques. When considering core decompression for the treatment of early stage avascular necrosis, the multiple small bore technique removed less bone volume, thereby potentially leading to higher load to failure.