Introduction Krackow Type II valgus deformity is defined by attenuation of the medial collateral ligament (MCL). However, little quantitative information exists about associated intra-operative MCL laxity. Furthermore, a corollary may exist in varus deformity with associated lateral ligament laxity but is poorly described. Robotic-assisted total knee arthroplasty (raTKA) includes quantitative assessment of intraoperative ligament function. This study evaluated whether increased preoperative medial or lateral radiographic joint space width (JSW) in valgus or varus knees, was associated with increased intraoperative soft tissue laxity of the respective compartment. Methodology Intraoperative data from 348 consecutive raTKAs with 270 varus knees (hip-knee-ankle angle [HKA]<-2°), and 78 valgus knees, (HKA>2°) were retrospectively reviewed. For varus knees, lateral JSW was measured on preoperative, standing anteroposterior radiographs to determine lateral widening (threshold 8.0mm). For valgus knees, medial JSW was evaluated to determine medial widening (threshold 7.0mm). Intraoperative medial and lateral gaps at 0° and 90° had been recorded during manual stress testing. Linear regression was performed to determine associations between intra-operative gaps, radiographic JSW, and HKA. Results 51 varus knees demonstrated lateral widening and 15 valgus knees had medial widening. In varus knees, lateral JSW was positively associated with the lateral extension (β=0.76, P <0.001) and flexion (β=0.74, P <0.001) gaps. Similarly, for valgus knees, medial JSW was positively associated with the medial extension (β=0.75, P <0.001) and flexion (β=0.77, P <0.001) gaps. Conclusion Increased preoperative radiographic JSW of the medial and lateral compartment in valgus and varus knees, predicted increased intraoperative gaps of that compartment, consistent with ligament attenuation.
Differences in Orthopaedic Surgeon Merit-based Incentive Payment System (MIPS) Performance, Demographics, and Patient Populations Based on Patient Social Risk
Background: The Centers for Medicare & Medicaid Services (CMS) Merit-based Incentive Payment System (MIPS) has undergone numerous changes to promote care for patients at high social risk. However, the effect of these changes on surgeon MIPS performance and caseload selection remains unclear. Thus, the purpose of this study was to evaluate how orthopaedic surgeon MIPS scores, demographics, practice characteristics, and patient populations varied on the basis of patient social risk in 2017 compared with 2021. Methods: CMS data were utilized to examine U.S. orthopaedic surgeons. Surgeons were placed into social-risk quintiles on the basis of the proportion of their patients who were dually eligible for Medicare and Medicaid, with the highest quintile representing the highest social risk. Demographics, practice location characteristics, patient data, and MIPS performance were assessed for the years 2017 and 2021. Differences between social-risk quintiles were assessed utilizing chi-square, Student t, and Wilcoxon signed-rank tests and multivariable logistic regression. Results: In 2017, surgeons with caseloads at the highest, compared with the lowest, social risk had lower MIPS performance scores (mean [and standard deviation], 66.0 ± 37.6 versus 70.1 ± 33.5; p < 0.001). However, in 2021, orthopaedic surgeons with caseloads at the highest, compared with the lowest, social risk had significantly higher MIPS performance scores (mean, 88.7 ± 16.9 versus 81.5 ± 18.3; p < 0.001). In terms of demographics, in 2021, orthopaedic surgeons with caseloads at the highest, compared with the lowest, social risk were more often women (9.2% versus 3.6%; p < 0.001), more often had a DO degree (11.2% versus 6.6%; p < 0.001), more recently graduated from medical school (mean, 23.0 ± 12.9 versus 25.7 ± 10.9 years; p < 0.001), and worked in areas with higher Distressed Communities Index (DCI) distress scores (mean, 56.9 ± 27.3 versus 35.1 ± 25.2; p < 0.001). Similar findings were present in 2017. Conclusions: The addition of the Complex Patient Bonus to the MIPS in 2020 may have reduced performance inequities in MIPS scoring for surgeons with caseloads at high social risk. However, the demographics and practice patterns of the orthopaedic surgeons caring for populations at the highest social risk remained consistent between years. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
Risk Factors in Patients Who Had Prior Renal or Liver Transplant Undergoing Primary Total Hip Arthroplasty
Background: Solid organ transplant (SOT) recipients are living longer and, consequently, more of them require elective total hip arthroplasty (THA) to restore mobility and improve quality of life. Because these patients are chronically immunosuppressed and often burdened by multiple comorbidities, their peri-operative risk profile may differ substantially from that of the general THA population. This study aimed to evaluate risk factors associated with acute medical and surgical complications, implant survivorship, and overall mortality in patients with a history of SOT who underwent THA. Methods: A total of 173 THA procedures were reviewed in patients with previous SOT. Among them, 64 had undergone liver transplantation (LT), 83 had received renal transplants (RT), and 26 had experienced more than one type of organ transplant (MT). Kaplan–Meier survival analysis was employed to estimate median survival. Complications were examined using univariate analysis through mixed-effects logistic regression, while Cox regression was utilized to assess mortality risk. The median follow-up period extended to 99 months. Results: The proportion of patients experiencing at least one acute medical event was 27% in the LT group, 33% in the RT group, and 38% in the MT group, with no statistically significant difference between groups (p = 0.5). American Society of Anesthesiologists Class (ASA) 4 (Odds Ratio (OR) = 28; p = 0.006) and treatment with bisphosphonates (OR = 2.25; p = 0.03) were associated with higher risk of acute medical complications. Increased age at the time of SOT was linked to a reduced likelihood of surgical complications (OR = 0.94, p = 0.008), as was older age at the time of undergoing THA (OR = 0.92, p = 0.001). The observed rates of reoperation and implant revision were 3% and 1%, respectively. The estimated patient survivorship rates at 1, 5, and 10 years were 98.6, 82, and 58.4%, respectively. Older age at SOT (Hazard Ratio (HR) = 1.06, p < 0.001), at THA (HR = 1.08, p < 0.001), ASA 4 at THA (HR = 7.57, p = 0.02), and atrial fibrillation (AFib) (HR = 3.13, p = 0.02) were associated with higher mortality. Conclusions: ASA 4 and bisphosphonates were associated with a higher risk of acute medical complications, whereas older age was associated with lower surgical complications. Additionally, older age, ASA 4, and AFib were associated with higher mortality.
Isolation of Multiple Positive Cultures at Resection Arthroplasty is a Predictor of Failure Following Reimplantation
Background: Although it is well established that the type of organism can be a risk factor for failure in patients with periprosthetic joint infection (PJI), no study to date has examined the impact of the number of positive cultures on treatment outcomes in patients undergoing 2-stage exchange. The purpose of this multicenter study was to determine the prognostic utility of multiple positive cultures at resection as a predictor of failure following reimplantation. Methods: This retrospective multicenter study identified 437 patients with chronic knee PJI who had undergone 2-stage exchange arthroplasty with a minimum of 1 year of follow-up following reimplantation. PJI was defined with use of the 2013 Musculoskeletal Infection Society (MSIS) criteria. Patients with culture-negative PJI were excluded (n = 138). Treatment failure was defined as either any reoperation for infection or PJI-related mortality. Multivariable regression controlling for risk factors for failure after a 2-stage arthroplasty was performed to determine whether ≥2 positive intraoperative cultures at resection can predict outcomes following reimplantation when compared with a single positive culture. Results: Two hundred and ninety-nine patients were included. At a mean follow-up of 6.2 ± 2.6 years, 48 patients (16.1%) experienced failure. Patients who had a failure were more likely to have had a longer interstage interval (p = 0.038) and were also more likely to have had ≥2 positive cultures at the time of resection arthroplasty (95.8% versus 75.3%; p = 0.001). On regression analysis, ≥2 positive cultures at resection was the only variable that was identified as a risk factor for failure following reimplantation in both the univariate (odds ratio [OR], 7.55 [95% CI, 2.24 to 47.0]; p = 0.006) and multivariable models (OR, 8.12 [95% CI, 2.31 to 51.9]; p = 0.005). Conclusions: This is the first study to examine the impact of the number of positive cultures on outcomes in patients with PJI. We found that the presence of ≥2 positive cultures at resection was an indicator of a poor prognosis and resulted in a greater than eightfold increase in the risk of treatment failure in patients undergoing a 2-stage exchange. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
Does Merit-based Incentive Payment System Performance Differ Based on Orthopaedic Surgeon Gender?
Background Value-based care payment and delivery models such as the recently implemented Merit-based Incentive Payment System (MIPS) aim to both provide better care for patients and reduce costs of care. Gender disparities across orthopaedic surgery, encompassing reimbursement, industry payments, referrals, and patient perception, have been thoroughly studied over the years, with numerous disparities identified. However, differences in MIPS performance based on orthopaedic surgeon gender have not been comprehensively evaluated. Questions/purposes After controlling for potentially confounding variables such as experience, geography, group size, and Medicare beneficiary characteristics, does MIPS performance differ between men and women orthopaedic surgeons? Methods The Medicare Physician and Other Practitioners and the Physician Compare databases were queried for years 2017, the first year MIPS was incorporated, and 2021, the most recent year with MIPS data published, to identify all physicians with a self-reported specialty of orthopaedic surgery. Together, these databases include all physicians who submitted at least 11 Medicare claims each year. Physician gender, US census region, years in practice, group practice size, billing practices, and patient demographic characteristics were collected for each surgeon. The MIPS Performance database was used to extract an overall MIPS performance score for each surgeon for each year. Payment adjustments, which are determined based on overall MIPS performance score, were derived for each surgeon based on the thresholds published by the Centers for Medicare & Medicaid Services. Payment adjustments include a negative adjustment, neutral adjustment, positive adjustment, or exceptional performance bonus and are associated with different thresholds each year. Statistical differences based on surgeon gender were assessed utilizing chi-square tests for categorical data, Student t-test for parametric continuous data, and Wilcoxon signed-rank test for nonparametric continuous data. Univariable and multivariable analyses were performed to analyze the relationship between surgeon gender and MIPS performance. Results After controlling for other patient and surgeon variables, woman gender was associated with a slightly increased MIPS performance score in 2021 (β 1.5 [95% confidence interval (CI) 0.02 to 3.00]; p = 0.047). However, this finding was statistically fragile, with the lower bound 95% CI being very close to the line of no difference. No association between surgeon gender and MIPS performance score was found in 2017 (β 2.2 [95% CI -0.5 to 4.9]; p = 0.11). Additionally, no relationship was found between gender and receiving either an exceptional performance MIPS bonus or a MIPS penalty in either year. Conclusion Women orthopaedic surgeons scored slightly higher on the MIPS in 2021, after controlling for surgeon and patient variables, despite providing care for a higher percentage of dual Medicare-Medicaid eligible patients and more medically complex patients. However, this finding was statistically fragile, with a small effect size, a 95% CI close to 0, and no consistent association in MIPS performance in 2017. Additionally, with no differences in MIPS performance bonuses or penalties, the clinical monetary impact of this difference may be minimal. Clinical Relevance The observed association between surgeon gender and MIPS performance scores in 2021, with women orthopaedic surgeons achieving slightly higher scores, raises interesting questions about potential differences in practice behaviors, communication styles, care quality, or other unmeasured variables. These findings may reflect true differences in how care is delivered or documented as scored by the MIPS. However, given the small effect size, statistical fragility, and inconsistency across years, there is a chance that this finding may be spurious. That being so, future research should aim to validate or refute these findings by examining a broader range of variables including documentation practices, practice behaviors, institutional differences, potential systemic biases in scoring methodologies, and patient outcomes. Understanding whether these differences are true is important to ensure that performance metrics like MIPS accurately and equitably reflect care quality.
Multicenter Randomized Clinical Trial of Highly Cross-Linked Polyethylene Versus Conventional Polyethylene in 518 Primary TKAs at 10 Years
Background: Second-generation highly cross-linked polyethylene (HXLPE) has revolutionized total hip arthroplasty. However, the long-term risks and benefits of HXLPE in primary total knee arthroplasty (TKA) remain unknown. This randomized clinical trial evaluated implant survivorship, complications, radiographic results, and clinical outcomes of HXLPE and conventional ultra-high molecular weight polyethylene (UHMWPE) inserts in primary TKAs. Methods: We enrolled 518 patients (518 knees) who underwent primary TKA in 3 centers within 1 tertiary referral network. The mean age was 67 years, the mean body mass index was 32 kg/m 2 , and 58% of the patients were women. All of the patients underwent primary TKA with a cemented posterior-stabilized tibial insert and patellar resurfacing. Randomization proceeded via stratified dynamic allocation. The patients were blinded to their study group allocation: those in the control group (254 knees) underwent TKA with an UHMWPE insert (N2Vac; Stryker); those in the treatment group (264 knees) received an HXLPE insert (X3; Stryker). Kaplan-Meier survivorship, radiographic results, and clinical outcomes were assessed. This trial was registered with ClinicalTrials.gov. The mean follow-up was 11 years. Results: The 10-year overall survivorship free from any revision and from any reoperation was 96% and 94%, respectively. There were no differences in the risk of revision or reoperation between the groups (p > 0.05). There were a total of 19 revisions. Revision indications included periprosthetic joint infection (14 knees), instability (4 knees), and open reduction and internal fixation (ORIF) for a patellar fracture due to osteolysis around a UHMWPE insert (1 knee). There were no revisions due to polyethylene wear, osteolysis, or fracture of the post in the HXLPE group. The radiographic results and clinical outcomes were otherwise similar. Conclusions: Notably, no wear-related failures were identified in the HXLPE group, but there was 1 case of osteolysis in the UHMWPE group. Level of Evidence: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.
Intraosseous regional prophylaxis in total knee arthroplasty
Prophylactic antibiotics are important in reducing the risk of periprosthetic joint infection (PJI) following total knee arthroplasty. Their effectiveness depends on the choice of antibiotic and the optimum timing of their administration, to ensure adequate tissue concentrations. Cephalosporins are typically used, but an increasing number of resistant organisms are causing PJI, leading to the additional use of vancomycin. There are difficulties, however, with the systemic administration of vancomycin including its optimal timing, due to the need for prolonged administration, and potential adverse reactions. Intraosseous regional administration distal to a tourniquet is an alternative and attractive mode of delivery due to the ease of obtaining intraosseous access. Many authors have reported the effectiveness of intraosseous prophylaxis in achieving higher concentrations of antibiotic in the tissues compared with intravenous administration, providing equal or enhanced prophylaxis while minimizing adverse effects. This annotation describes the technique of intraosseous administration of antibiotics and summarizes the relevant clinical literature to date.Cite this article: Bone Joint J 2023;105-B(11):1135–1139.
Does Preoperative Pharmacogenomic Testing of Patients Undergoing TKA Improve Postoperative Pain? A Randomized Trial
Abstract Background Pharmacogenomics is an emerging and affordable tool that may improve postoperative pain control. One challenge to successful pain control is the large interindividual variability among analgesics in their efficacy and adverse drug events. Whether preoperative pharmacogenomic testing is worthwhile for patients undergoing TKA is unclear. Questions/purposes (1) Are the results of preoperative pharmacogenetic testing associated with lower postoperative pain scores as measured by the Overall Benefit of Analgesic Score (OBAS)? (2) Do the results of preoperative pharmacogenomic testing lead to less total opioids given? (3) Do the results of preoperative pharmacogenomic testing lead to changes in opioid prescribing patterns? Methods Participants of this randomized trial were enrolled from September 2018 through December 2021 if they were aged 18 to 80 years and were undergoing primary TKA under general anesthesia. Patients were excluded if they had chronic kidney disease, a history of chronic pain or narcotic use before surgery, or if they were undergoing robotic surgery. Preoperatively, patients completed pharmacogenomic testing (RightMed, OneOME) and a questionnaire and were randomly assigned to the experimental group or control group. Of 99 patients screened, 23 were excluded, one before randomization; 11 allocated patients in each group did not receive their allocated interventions for reasons such as surgery canceled, patients ultimately undergoing spinal anesthesia, and change in surgery plan. Another four patients in each group were excluded from the analysis because they were missing an OBAS report. This left 30 patients for analysis in the control group and 38 patients in the experimental group. The control and experimental groups were similar in age, gender, and race. Pharmacogenomic test results for patients in the experimental group were reviewed before surgery by a pharmacist, who recommended perioperative medications to the clinical team. A pharmacist also assessed for clinically relevant drug-gene interactions and recommended drug and dose selection according to guidelines from the Clinical Pharmacogenomics Implementation Consortium for each patient enrolled in the study. Patients were unaware of their pharmacogenomic results. Pharmacogenomic test results for patients in the control group were not reviewed before surgery; instead, standard perioperative medications were administered in adherence to our institutional care pathways. The OBAS (maximum 28 points) was the primary outcome measure, recorded 24 hours postoperatively. A two-sample t-test was used to compare the mean OBAS between groups. Secondary measures were the mean 24-hour pain score, total morphine milligram equivalent, and frequency of opioid use. Postoperatively, patients were assessed for pain with a VAS (range 0 to 10). Opioid use was recorded preoperatively, intraoperatively, in the postanesthesia care unit, and 24 hours after discharge from the postanesthesia care unit. Changes in perioperative opioid use based on pharmacogenomic testing were recorded, as were changes in prescription patterns for postoperative pain control. Preoperative characteristics were also compared between patients with and without various phenotypes ascertained from pharmacogenomic test results. Results The mean OBAS did not differ between groups (mean ± SD 4.7 ± 3.7 in the control group versus 4.2 ± 2.8 in the experimental group, mean difference 0.5 [95% CI -1.1 to 2.1]; p = 0.55). Total opioids given did not differ between groups or at any single perioperative timepoint (preoperative, intraoperative, or postoperative). We found no difference in opioid prescribing pattern. After adjusting for multiple comparisons, no difference was observed between the treatment and control groups in tramadol use (41% versus 71%, proportion difference 0.29 [95% CI 0.05 to 0.53]; nominal p = 0.02; adjusted p > 0.99). Conclusion Routine use of pharmacogenomic testing for patients undergoing TKA did not lead to better pain control or decreased opioid consumption. Future studies might focus on at-risk populations, such as patients with chronic pain or those undergoing complex, painful surgical procedures, to test whether pharmacogenomic results might be beneficial in certain circumstances. Level of Evidence Level I, therapeutic study.
ANALYZING TRENDS IN PROM AND MCID REPORTING IN TOTAL JOINT REPLACEMENT OVER THE PAST DECADE
AbstractIntroductionMinimum clinically important differences (MCIDs) are critical to understanding changes in patient-reported outcome measure (PROM) scores after total joint arthroplasty (TJA). The usage and adoption of MCIDs not been well-studied. This study was performed to IDENTIFY trends in PROM and MCID use after TJA over the past decade.MethodsAll articles published in the calendar years of 2010 and 2020 in CORR, JBJS, and the Journal of Arthroplasty were reviewed. Articles relating to clinical outcomes in primary total hip arthroplasty (THA) or total knee arthroplasty (TKA) were included. For each article, all reported PROMs and (if present) accompanying MCIDs were recorded. The use of PROMs and MCIDs were compared between articles published in 2010 and 2020.ResultsOverall, 263 articles from 2010 and 546 articles from 2020 were included. The total number of articles reporting any PROM after THA and TKA increased from 131 in 2010 to 194 in 2020, but the proportion of articles reporting PROMs decreased from 49.8% (131/263) to 35.5% (194/546). Both the total number and proportion of articles reporting MCIDs increased from 2.3% (3/131) in 2010 to 16.5% (32/194) in 2020. These trends persisted when analyzing THA and TKA articles individually.ConclusionsBoth the absolute number and proportion of articles reporting MCIDs in conjunction with PROMs after TJA has increased in the past decade but remains low. We recommend that journal editors and meeting organizers encourage the inclusion of MCID information in all reports on clinical outcomes after joint replacement.
PROSPECTIVE RANDOMIZED STUDY USING PHARMACOGENETICS TO OPTIMIZE PERIOPERATIVE PAIN MANAGEMENT AFTER TOTAL KNEE ARTHROPLASTY
AbstractIntroductionAdverse reactions to pain medication and pain can delay discharge after outpatient knee arthroplasty (TKA). Pharmacogenomics is an emerging tool that might help reduce adverse events by tailoring medication use based on known genetic variations in the CYP genes determining drug metabolism. This study was undertaken to evaluate whether pre-operative pharmacogenomic testing could optimize peri-operative pain management in patients undergoing total knee arthroplasty (TKA).MethodsThis prospective, randomized study was performed in adults undergoing primary TKA. Patients in the experimental group underwent pre-operative pharmacogenomic evaluation and medication adjustments. Medications were not optimized for control patients. The Overall Benefit of Analgesic Score (OBAS) at 24 hours post-op was the primary outcome. Postoperative pain scores (VAS scale), total opioid use, time in recovery, and time to discharge were also compared.Results76 patients enrolled. 93% of patients had a poor-intermediate phenotype for at least one of four CYP genes. OBAS did not differ significantly between the two groups (4.2 control vs. 4.7 experimental; 95% CI −1.1 to 2.1) and was below the minimum clinically important difference of 2.0 points. Furthermore, there were no differences in any OBAS subscale including pain, satisfaction, or nausea. There were no differences in time in the recovery area or to discharge from hospital, or narcotic use.ConclusionsDespite many patients having a poor-intermediate phenotype for a CYP gene, pharmacogenomic testing prior to TKA and medication adjustment did not improve anesthesia or pain management outcomes, time to discharge or mean total opioid use after surgery.