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.

Favourable mid-term outcomes following unicompartmental knee arthroplasty with wider patient selection: A single-centre experience.

OBJECTIVE: The purpose of this study was to determine surgical outcomes of robotic-assisted UKAs utilizing a wider set of indications than traditionally utilized. Additionally, we seek to determine alternate predictive factors as potential surgical indications and contraindications. METHODS: A prospectively maintained institutional joint registry was queried at a single academic centre for all patients that underwent robotic-assisted UKA between January 2010-December 2016. Surgical indication included isolated medial or lateral compartment degenerative disease with a stable knee based on physical exam. In 2013, haemoglobin A1C levels over 7.5% were considered contraindications, which was lowered to 7.0% in 2015. Preoperative alignment, age, activity level and degree of pain were not contraindications for surgery. Preoperative demographics, Oxford scores, radiographic (joint space), comorbidities and operative data were collected and reviewed to determine factors related to conversion to TKA and survivorship of the primary implant. RESULTS: In total, 1878 cases were performed; however, excluding multi-joint knees, there were a total of 1186 knees in 1014 patients with a minimum 4-year follow-up. The mean age was 63.4 â€‹± â€‹10.7 years and mean follow-up was 76.4 â€‹± â€‹17.4 months. Mean BMI was 32.3 â€‹± â€‹6.5 â€‹kg/m2. (52.9% females, 47.1% males). There were 901 patients undergoing medial UKA, 122 patients undergoing lateral UKA and 69 patients undergoing patellofemoral UKA. In total, 85 (7.2%) knees underwent conversion to TKA. Preoperative factors such as the degree of preoperative valgus deformity (p â€‹= â€‹0.01), greater operative joint space (p â€‹= â€‹0.04), previous surgery (p â€‹= â€‹0.01), inlay implant (p â€‹= â€‹0.04) and pain syndrome (p â€‹= â€‹0.01) were associated with increased risk of revision surgery. Factors associated with decreased implant survivorship included patients with history of previous surgery (p â€‹< â€‹0.01), history of pain syndrome (p â€‹< â€‹0.01) and greater preoperative joint space (>2 â€‹mm) (p â€‹< â€‹0.01). There was no association of BMI to conversion to TKA. CONCLUSION: Robotic-assisted UKA with wider patient selection demonstrated favourable outcomes at 4 years with survivorship greater than 92%. The present series agree with emerging indications that do not exclude patients based on age, BMI, or degree of deformity. However, increased operative joint space, inlay design, history of surgery and coexistence of pain syndrome are factors that increase risk of conversion to TKA. LEVEL OF EVIDENCE: Level III.

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.

Shared and unique risk factors for readmission exist following upper and lower extremity arthroplasty in the 30-day postoperative period.

PURPOSE: Joint arthroplasty has become increasingly more common in the United States, and it is important to examine the patient-based risk factors and surgical variables associated with hospital readmissions. The purpose of this study was to identify stratified rates and risk factors for readmission after upper extremity (shoulder, elbow, and wrist) and lower extremity (hip, knee, and ankle) arthroplasty. METHODS: All patients undergoing upper and lower extremity arthroplasty from 2008-2018 were identified using the National Surgical Quality Improvement Program dataset. Patient demographics, medical comorbidities and surgical characteristics were examined utilizing uni- and multi-variate analysis for significant predictors of 30-days hospital readmission. RESULTS: A total of 523,523 lower and 25,215 upper extremity arthroplasty patients were included in this study. A number of 22,183 (4.2%) lower and 1072 (4.4%) upper extremity arthroplasty patients were readmitted within 30 days of discharge. Significant risk factors for 30-days readmission after lower extremity arthroplasty included age, Body Mass Index (BMI), operative time, dependent functional status, American Society of Anesthesiologists (ASA) score ≥3, increased length of stay, and various medical comorbidities such as diabetes, tobacco dependency, and chronic obstructive pulmonary disease (COPD). An overweight BMI was associated with a lower odds of 30-days readmission when compared to a normal BMI for lower extremity arthroplasty. Analysis for upper extremity arthroplasty revealed similar findings of significant risk factors for 30-days hospital readmission, although diabetes mellitus was not found to be a significant risk factor. CONCLUSION: Nearly one in 25 patients undergoing upper and lower extremity arthroplasty experiences hospital readmission within 30-days of index surgery. There are several modifiable risk factors for 30-days hospital readmission shared by both lower and upper extremity arthroplasty, including tobacco smoking, COPD, and hypertension. Optimization of these medical comorbidities may mitigate the risk short-term readmission following joint arthroplasty procedures and improve overall cost effectiveness of perioperative surgical care.

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).

Gout As a Predictor of Total Knee Arthroplasty Outcomes and Costs.

Gout is the most common inflammatory arthritis and affects approximately 4% of the U.S. population. As the prevalence of gout and the number of total knee arthroplasties (TKAs) performed continue to increase, the literature on TKA in patients with gout remains scant. The purpose of this study was to evaluate the outcomes of patients with gout following TKA at a population level, that is, how patient with gout fair after TKA. We hypothesized that patients with gout have higher rates of complications and higher costs compared with controls. A case-control study was designed to evaluate two cohorts of Medicare patients who underwent TKA whose only distinguishing feature was the presence or absence of gout. Matching was performed to decrease confounding at a 1:1 ratio based on age, gender, and Charlson comorbidity index (CCI), (10-year survival predictor). The Medicare standard analytical files were queried through International Classification of Disease and current procedural terminology codes. A total of 15,238 patients were evaluated with 7,619 in each cohort. There were no age, gender, or CCI differences and 57.4% were females. Day of surgery and 90-day post-surgery costs were both significantly greater in those with gout (p < 0.001 for both). Multivariate analysis revealed that gout patients had increased odds of infection (odds ratio [OR] 1.229, p = 0.019), cardiac arrest (OR 1.354, p = 0.002), pneumonia (OR 1.161, p < 0.001), hematoma (OR 1.204, p = 0.002), and development of capsulitis (OR 1.208, p = 0.012). Nonetheless these patients had a decreased risk of pulmonary emboli (OR 0.835, p = 0.016). Our results support our hypothesis that patients with gout have higher rates of postoperative complications and increased day of surgery and 90-day costs of care after TKA. Given the high prevalence of gout in the United States, additional study on the utility of preoperative gout optimization for TKA patients is warranted. The level of evidence of this study is III, and it is a retrospective case-control study.

Revision Total Joint Arthroplasty: Final Stop Tertiary Referral Center.

High complication rates associated with revision total knee arthroplasty (TKA) and total hip arthroplasty (THA) may unequally burden tertiary referral centers, which manage medically complex patients. The authors aimed to quantify TKA and THA referral patterns at a tertiary referral center based on travel distance and patient comorbidities. All patients who underwent primary or revision TKA or THA at the investigating institution from 2012 to 2016 were identified. Travel distance was calculated using each patient's home address and stratified into less than 25 miles, 25 to 74 miles, and 75 miles or more. Age, body mass index, Charlson Comorbidity Index, and postoperative clinical data were identified. Patients were analyzed based on procedure performed and travel distance. A total of 4245 procedures were included for analysis (1754 primary TKAs, 432 revision TKAs, 1503 primary THAs, and 556 revision THAs). Patients living 75 miles or more away had significantly higher odds of undergoing revision arthroplasty compared with patients living within 25 miles (knee: odds ratio [OR], 2.43; hip: OR, 2.61; P<.001). Charlson Comorbidity Index did not increase with travel distance. Patients traveling 75 miles or more were more likely to have periprosthetic fracture (OR, 3.91; P=.011) and less likely to have dislocation (OR, 0.54; P=.026) as the surgical indication for revision. Patients referred to a tertiary center were more likely to necessitate revision total joint arthroplasty but did not differ in comorbidity profile compared with local patients. Periprosthetic fracture, a particularly high-risk surgical indication, was overrepresented among referral patients. These data suggest that factors such as underlying diagnosis, but not preoperative medical comorbidities, may influence referral patterns. [Orthopedics. 2021;44(4):e477-e481.].

A History of Past Prostate Cancer Still Carries Risk After Total Knee Arthroplasty.

Prostate cancer (PCa) is one of the most prevalent diseases in the North American elderly population. Moreover, many patients undergo prostate resection without further treatment and are often considered cured. As such, it is expected that many undergo total knee arthroplasty (TKA) for osteoarthritis while having a history of PCa. Nonetheless, limited research is available on this topic, and without it, surgeons may not be aware of increased complication rates. Therefore, the purpose of this study was to evaluate whether patients at a national level with a history of PCa are at increased risk for complications after TKA. A retrospective case-control, comorbidity matched paired analysis was performed. Patients were identified based on International Classification of Diseases, Ninth Revision codes and matched 1:1 ratio to age, smoker status, chronic kidney disease, diabetes, chronic lung disease, smoking status, and obesity. Patients with active disease were excluded. The 90-day outcomes of TKA were compared through univariate regressions (odds ratios [ORs] and 95% confidence intervals). A total of 2,381,706 TKA patients were identified, and after matching, each comprised 113,365 patients with the same prevalence of the matched comorbidities and demographic characteristics. A significant increase in thromboembolic events that was clinically relevant was found in pulmonary embolisms (PEs) (1.44 vs. 0.4%, OR: 3.04, p < 0.001), Moreover, an increased rate of deep vein thromboses was also seen but was found to be not clinically significant (2.55 vs. 2.85%, OR: 1.19). Although length of stay and other complications were similar, average reimbursements were higher for those with a history of PCa. In conclusion, a history of prior PCa carries significant risk as these patients continue to develop increased PE rates during the 90-day postoperative period which appears to lead to greater economic expenditure. Surgeons and payers should include this comorbidity in risk and patient-specific payment models.

Flash Sterilization and Component Reimplantation Is a Viable Option for Articulating Antibiotic Spacers in Periprosthetic Knee Infections.

The articulating antibiotic spacer is a treatment utilized for two-stage revision of an infected total knee arthroplasty. The original femoral component is retained and reused in one described variation of this technique. The purpose of this study is to determine the safety and efficacy of flash sterilization of the femoral component for reimplantation in an articulating antibiotic spacer for the treatment of chronic periprosthetic joint infection. A total of 10 patients were identified prospectively with a culture positive infected total knee arthroplasty. The patients underwent explantation, debridement, and placement of an articulating antibiotic spacer consisting of the explanted and sterilized femoral component and a new polyethylene tibial insert. The explanted tibial components were cleaned and flash-sterilized with the femoral components, but the components were then aseptically packaged and sent to our microbiology laboratory for sonication and culture of the sonicate for 14 days. Ten of 10 cleaned tibial components were negative for bacterial growth of the infecting organism after final testing and analysis. At 18-month follow-up, 9 of 10 of patients remained clear of infection. Among the 10 patients, 7 were pleased with their articulating spacer construct and had no intention of electively pursuing reimplantation. Also, 3 of 10 of patients were successfully reimplanted at a mean of 6.5 months after explantation. Autoclave sterilization and reimplantation of components may be a safe and potentially resource-sparing method of articulating spacer placement in two-stage treatment of PJI. Patient follow-up demonstrated clinical eradication of infection in 90% of cases with good patient tolerance of the antibiotic spacer.

Two-Stage Exchange Using a Short Intramedullary Nail for Treatment of Periprosthetic Knee Infections: A Technique Worth Questioning.

Periprosthetic joint infections (PJIs) following total knee arthroplasty (TKA) are serious orthopaedic complications that pose marked burdens to both patients and health care systems. At our institution, two-stage exchange with a temporary short antibiotic cement-coated intramedullary nail was utilized for the treatment of repeat PJIs in a series of compromised patients with considerable bone loss. This study reports on (1) success rates, (2) functional and pain outcomes, (3) and complications for patients receiving a temporary short intramedullary nail for the treatment of PJI. Our institutional database was queried for all repeat knee PJI patients between March 1st, 2009 and February 28th, 2015. Patients with type II/III Anderson Orthopaedic Research Institute (AORI) bone defects who underwent two-stage exchange arthroplasty with a short antibiotic-coated intramedullary nail were included for analysis (n = 31). Treatment success was determined using the Delphi-based consensus definition of a successfully treated PJI: infection eradication (healed wound with no recurrence of infection by the same organism), no further surgical intervention for infection after reimplantation, and no PJI-related mortality. A paired t-test was performed to assess for continuous variables. A total of 26 patients went on to reimplantation, while 5 patients retained the intramedullary nail. Overall treatment success was 74.2%. Range of motion significantly decreased postoperatively (102.1 vs. 87.3 degrees; p < 0.001), while Knee Society Scores (function) significantly increased (55.6 vs. 77.7, p < 0.001). A majority of patients were full weight-bearing immediately following surgery (38.7%). Treating poor health status patients with PJI of the knee can be difficult after multiple revisions. With a success rate similar to conventional methods, our results demonstrate that two-stage exchange with a temporary short intramedullary nail may be a desirable treatment option for patients with bony defects wishing to avoid amputation or permanent arthrodesis. However, this method does not outperform other treatment modalities, and may not be suitable for all patients. Patient expectations and health status should be carefully assessed to determine if this procedure is appropriate in this complex patient population.

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.

All-Polyethylene Tibia: An Opportunity for Value-Based Care in Bundled Reimbursement Initiatives.

Surgeons play a critical role in making cost-effective decisions that maintain high-quality patient outcomes, which is the current focus of the Centers for Medicare & Medicaid Services. All-polyethylene tibial (APT) components often cost less during total knee arthroplasty (TKA). The authors sought to determine the relative cost savings of APT, as well as their effect on 90-day quality outcome metrics. This was a retrospective review of primary TKAs performed at a single tertiary referral center participating in the Comprehensive Care for Joint Replacement model, by 2 surgeons, from 2015 to 2017. Patient demographic data and direct hospital costs were collected, and patients were stratified by APTs vs metal-backed components. Univariable and multivariable analyses were performed for all outcome metrics. A total of 188 primary TKAs were included (92 APT, 96 metal-backed). Patients receiving APT components were older (P<.001) and had a lower body mass index (P<.001), but there was no difference in sex or American Society of Anesthesiologists score between groups. Operative time was significantly less (mean, 13 minutes) and direct surgery costs were significantly lower for APTs (P<.001). A multivariable regression model for surgical costs demonstrated significant savings (P<.001), and total hospital cost demonstrated a 6.2% average savings with APT. There was no difference in 90-day emergency department visits or re-admissions. This study demonstrates that the use of an APT is able to significantly affect not only the surgical cost but also the total hospital admission cost while maintaining equivalent 90-day outcome metrics. Strategies like this should be considered in appropriately selected patients as the incidence of TKA continues to expand. [Orthopedics. 2021;44(1):e114-e118.].

Patient Risk Profile for Unplanned 90-Day Emergency Department Visits Differs Between Total Hip and Total Knee Arthroplasty.

Numerous studies have explored 90-day readmissions following total joint arthroplasty; however, there is a paucity of literature concerning 90-day emergency department (ED) visits. The authors aimed to characterize the risk factors for ED presentations and to determine the primary reasons for return, hypothesizing that certain medical comorbidities would account for resource utilization. The institutional database was queried for primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). Patients were stratified based on return visits to the ED within 90 days postoperatively. Univariable and multivariable analyses were performed to determine the factors most predictive of ED return for each THA and TKA. A total of 10,479 procedures resulted in 1234 90-day ED visits made by 937 patients. Significant predictors of 90-day ED return after THA included black race, age older than 80 years, congestive heart failure, valvular heart disease, metastatic disease, peripheral vascular disease, alcoholism, drug use, depression, and discharge to a skilled nursing facility. In contrast, only black race, liver insufficiency, cancer, and pulmonary hypertension were predictive of ED return following TKA. The primary risk factors for ED return differ for THA and TKA, and this is not currently reflected in the medical severity diagnosis-related group system. Specifically, black patients with multiple comorbidities are at high risk for unplanned ED visits following THA. This should be considered in patient counseling and outreach programs when attempting to mitigate the postoperative risks and to decrease 90-day resource utilization in this patient population. [Orthopedics. 2020;43(5):295-302.].

Comparing the Efficiency, Radiation Exposure, and Accuracy Using C-Arm versus O-Arm With 3D Navigation in Placement of Transiliac-Transsacral and Iliosacral Screws: A Cadaveric Study Evaluating an Early Career Surgeon.

OBJECTIVES: To compare the efficiency, radiation exposure to surgeon and patient, and accuracy of C-arm versus O-arm with navigation in the placement of transiliac-transsacral and iliosacral screws by an orthopaedic trauma fellow, for a surgeon early in practice. METHODS: Twelve fresh frozen cadavers were obtained. Preoperative computed tomography scans were reviewed to assess for safe corridors in the S1 and S2 segments. Iliosacral screws were assigned to the S1 segment in dysmorphic pelvises. Screws were randomized to modality and laterality. An orthopaedic trauma fellow placed all screws. Time of procedure and radiation exposure to the cadaver and surgeon were recorded. Three fellowship-trained orthopaedic trauma surgeons rated the safety of each screw on postoperative computed tomography scan. RESULTS: Six normal and 6 dysmorphic pelvises were identified. Eighteen transiliac-transsacral screws and 6 iliosacral screws were distributed evenly between C-arm and O-arm. Average operative duration per screw was significantly shorter using C-arm compared with O-arm (15.7 minutes ± 6.1 vs. 23.7 ± 8.5, P = 0.014). Screw placement with C-arm exposed the surgeon to a significantly greater amount of radiation (3.87 × 10 rads vs. 0.32 × 10, P < 0.001) while O-arm exposed the cadaver to a significantly greater amount of radiation (0.03 vs. 2.76 rads, P < 0.001). Two S2 transiliac-transsacral screws (1 C-arm and 1 O-arm) were categorized as unsafe based on scoring. There was no difference in screw accuracy between modalities. CONCLUSIONS: A difference in accuracy between modalities could not be elucidated, whereas efficiency was improved with utilization of C-arm, with statistical significance. A statistically significant increase in radiation exposure to the surgeon using C-arm was found, which may be clinically significant over a career. The results of this study can be extrapolated to a fellow or surgeon early in practice. The decision between use of these modalities will vary depending on surgeon preference and hospital resources.

The Who, What, and Where of Primary TKAs: An Analysis of HCUP Data from 2009 to 2015.

The aim of this study was to assess (1) temporal trends, (2) primary indication, (3) patient-level demographics (age, race, gender, health status, and median income quartile), and (4) region and hospital type for all patients receiving primary total knee arthroplasty (TKA) between 2009 and the third quarter of 2015. The National Inpatient Sample Database (NIS) was used to identify all patients who underwent a TKA between 2009 and the third quarter of 2015. Regression analysis was utilized to assess trends. Chi-square analysis was used to explore categorical variables whereas Kruskal-Wallis test was used to explore nonparametric continuous variables. TKA utilization increased between 2009 and 2015 with the highest volume occurring during the fall. Primary osteoarthritis was the primary indication in 98% of cases. There was an increase in minority representation among recipients. Black TKA recipients were younger and had lower median age-adjusted Charlson's comorbidity index (CCI). Black recipients were most likely to be of the lowest 25% of median income than any other races. The Midwest demonstrated the greatest increase in TKAs performed per 100,000 between 2009 and 2014. Case volumes shifted to urban teaching hospitals between 2009 and 2014. There were differences in age of presentation, preoperative morbidity, and income status among races. Furthermore, our findings revealed a more rapid growth in TKA procedures per 100,000 in the Midwest, in addition to volume shifts toward urban teaching hospitals. Future studies are needed to update our findings as well as explore trends in racial disparities for primary TKA recipients.

Dialysis Is Not Associated with Increased Risk of Perioperative Complications in TKA Patients after Adjusting for Pertinent Confounders.

With a growing prevalence for chronic renal failure, arthroplasty surgeons will find it more likely to have dialysis dependent patients present for knee replacement. Previous retrospective studies using a matched cohort of patients have reported worse perioperative outcomes for dialysis-dependent patients. However, many of these studies failed to control for pertinent confounders. This study aims to fill in that void. The present study compares lengths of stay, discharge status, and 30-day outcomes between dialysis-dependent TKA recipients and a matched cohort of nondialysis dependent TKA recipients. The National Surgical Quality Improvement Program database was used to identify the study cohorts. Patients were propensity score matched based on patient-specific demographic variables, preoperative functional status, and preoperative laboratory values. Generalized regression models were conducted to assess the effects of dialysis dependency on perioperative outcomes. Dialysis dependent patients demonstrated longer mean lengths of stay (+1.14) and a lower likelihood for home discharge (odds ratio [OR] = 0.503). There was no increased risk of 30-day complications in dialysis dependent TKA patients. Our findings demonstrate no increased risk of 30-day complications after TKA when adjusting for pertinent confounders. This suggests TKA is safe for well optimized dialysis dependent patients prior to surgery.

Cartilage oligomeric matrix protein in patients with osteoarthritis is independently associated with metastatic disease in prostate cancer.

Metastatic prostate cancer has a 5-year survival rate of 30%. Identifying predictors of metastasis outcome could potentially reduce patient mortality. The objective of this study was to determine whether osteoarthritis had an impact on outcomes of prostate cancer including death, local recurrence and/or metastasis and to determine whether cartilage oligomeric matrix protein was involved. We performed a retrospective case-control study of patients with prostate cancer with and without the diagnosis of osteoarthritis and completed immunohistochemistry (IHC) analysis of prostate (n=20) and lymph node (n=7) surgical specimens. We evaluated death, local recurrence and metastatic disease by various IHC biomarkers including prostate specific membrane antigen (PSMA), cartilage oligomeric matrix protein (COMP), CD31, and Ki-67. Our model identified osteoarthritis as an independent risk factor for metastatic disease (OR 5.24, 95% CI 1.49 - 18.41). Most notably, when joint arthroplasty was included in the model, osteoarthritis was no longer an independent risk factor for this outcome (p=0.071). IHC demonstrated that those with osteoarthritis, had greater expression of COMP in the prostate samples (mean 23.9% vs 5.84%, p<0.05) but not of Ki-67, CD31, or PSMA. This study identified and quantified increased metastatic disease in patients with osteoarthritis. Also, patients with osteoarthritis expressed increased COMP levels in the prostate and most likely in distant lymphatic nodes. Moreover, our findings suggest that joint arthroplasty may affect the ability of osteoarthritis to promote metastasis, which could impact treatment protocols and survival outcomes of the most common cause of cancer-related death (metastasis) in the United States.

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).

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.

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.