Rheumatoid Arthritis Is Not a Contraindication to Unicompartmental Knee Arthroplasty.

BACKGROUND: Rheumatoid arthritis (RA) has historically been considered a contraindication for unicompartmental knee arthroplasty (UKA). However, the widespread use of disease-modifying antirheumatic drugs has substantially improved the management of RA and prevented disease progression. The objective of this study was to ascertain whether RA impacts UKA revision-free survivorship. METHODS: Patients undergoing UKA from 2010 to 2021 were identified in an administrative claims database (n = 105,937) using Current Procedural Terminology code 27446. All patients who underwent UKA who had a diagnosis of RA with a minimum of 2-year follow-up (n = 1,422) were propensity score matched based on age, sex, and Elixhauser Comorbidity Index to those who did not have RA (n = 1,422). Laterality was identified using the 10th Revision of International Classification of Diseases codes. The primary outcome was ipsilateral revision to total knee arthroplasty (TKA) within 2 years, and the secondary outcome was ipsilateral revision at any time. RESULTS: Among the 1,422 patients who had a UKA and a diagnosis of RA, 37 patients (2.6%) underwent conversion to TKA within 2 years, and 48 patients (3.4%) underwent conversion to TKA at any point. In comparison, 28 patients (2.0%) in the propensity-matched control group underwent conversion to TKA within 2 years, and 40 patients (2.8%) underwent conversion to TKA at any point. Statistical analysis revealed no significant difference in conversion to TKA between patients who had and did not have RA, either within 2 years (P = .31) or anytime (P = .45). CONCLUSIONS: Patients who had RA and underwent UKA did not have an increased risk of revision to TKA compared to those who did not have RA. This may indicate that modern management of RA could allow for expanded UKA indications for RA patients.

Individualizing a Total Knee Arthroplasty with Three-Dimensional Planning.

Total knee arthroplasty (TKA) is evolving from mechanical alignment to more individualized alignment options in an attempt to improve patient satisfaction. Thirteen-year survival of kinematically aligned prostheses has recently been shown to be similar to mechanically aligned TKA, allaying concerns of long-term failure of this newer individualized technique. There is a complex inter-relationship of three-dimensional knee and limb alignment for a TKA. This article will review planning parameters necessary to individualize each knee, along with a discussion of how these parameters are related in three dimensions. Future use of computer software and machine learning has the potential to identify the ideal surgical plan for each patient. In the meantime, the material presented here can assist surgeons as newer individual alignment planning becomes a reality.

Clostridium difficile Infection Prior to Total Hip Arthroplasty Independently Increases the Risk of Periprosthetic Joint Infection.

BACKGROUND: Periprosthetic joint infection (PJI) following total hip arthroplasty (THA) is associated with major morbidity. There may be a link between the gut microbiome and an individual's overall immune system. A Clostridium difficile (C. difficile) infection portends poor gut microbiome health and has been previously associated with increased 90-day complication rates in total joint arthroplasty (TJA). The purpose of this study was to determine the effect of a previous history of C. difficile infection within 2 years of undergoing THA on PJI within 2 years postoperatively. METHODS: Patients undergoing THA from 2010 to 2021 were identified in a patient claims database (n = 770,075). Patients who had active records 2 years before and after THA as well as a history of C. difficile infection within 2 years prior to THA (n = 1,836) were included and propensity matched to a control group using age, sex, and Elixhauser comorbidity index. The primary outcome was the 2-year incidence of postoperative PJI. The exposed C. difficile infection cohort was stratified into 4 groups based on the time proximity of the C. difficile infection. Chi-square tests and logistic regressions were used to compare the groups. RESULTS: A C. difficile infection anytime within 2 years prior to total hip arthroplasty was independently associated with higher odds of PJI (OR [odds ratio]: 1.49 [95% CI (confidence interval) 1.09 to 2.02, P = .014]). Proximity of C. difficile infection to arthroplasty was associated with increased risk of PJI (infection 0 to 3 months before THA: OR 2.01 [95% CI 1.23 to 3.20], infection 3 to 6 months before THA: OR 1.84 [95% CI 1.06 to 3.04], infection 6 to 12 months before THA: OR 1.10 [95% CI 0.65 to 1.77], infection 1 to 2 years before THA: OR 1.40 [95% CI 0.94 to 2.06]). CONCLUSIONS: A C. difficile infection prior to THA is an independent risk factor for PJI. Proximity of C. difficile infection is associated with increased risk of PJI. Future investigations should evaluate how to adequately optimize patients prior to THA and pursue strategies to determine appropriate timing for proceeding with THA.

Posteromedial Periarticular Injection in Total Knee Arthroplasty: A Cadaveric Study.

Achieving optimal pain control in total knee arthroplasty has improved with the use of regional anesthesia and periarticular injections (PAIs). When performing a PAI, the relative location of the anesthetic spread is not well defined in comparison with an adductor canal block (ACB). In this study, our aim was to evaluate the location of posteromedial PAI spread compared with a surgeon administered ACB. One PAI and one surgeon-administered ACB were performed in the contralateral limbs of four human cadavers. The injectate was composed of methylene blue dye to visually inspect the dye spread from the tip of the needle. Dissections were performed on each cadaver to quantify the dye spread from the tip of the needle and compare the location of the dye spread. Dye spread location was characterized as either entering the adductor canal or including the posterior capsule. The mean distance of dye spread from the needle tip to the proximal most aspect of the dyed tissue was 10.125 cm in the ACB group compared with 6.5 cm in the posteromedial PAI group. In the ACB group, 4 of 4 injections were present in the adductor canal block group compared with 3 of 4 in the posteromedial PAI group. The posteromedial PAI group also had 3 of 4 injections involve the area around the posterior capsule compared with 0 of 4 in the ACB group. Posteromedial PAI appears to provide local delivery to both the adductor canal and the posterior capsule. Intraoperative, surgeon-administered ACB reliably delivers injectate to the adductor canal only but may allow for more proximal dye spread. Posteromedial PAI may provide a benefit in delivering injectate to the posterior capsule in addition to the ACB. Additional clinical studies are necessary to determine the clinical effects of this finding.

Does Preoperative Pharmacogenomic Testing of Patients Undergoing TKA Improve Postoperative Pain? A Randomized Trial.

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.

Periprosthetic Infection in Patients With Multiple Joint Arthroplasties.

The number of total joint arthroplasties performed in the United States is increasing every year. Owing to the aging population and excellent long-term prosthesis survival, 45% of patients who undergo joint arthroplasty will receive two or more joint arthroplasties during their lifetimes. Periprosthetic joint infection (PJI) is among the most common complications after arthroplasty. Evaluation and treatment of PJI in patients with multiple joint arthroplasties is challenging, and no consensus exists for the optimal management. Multiple PJI can occur simultaneously, synchronous, or separated by extended time, metachronous. Patient risk factors for both scenarios have been reported and may guide evaluation and long-term management. Whether to perform joint aspiration for asymptomatic prosthesis in the presence of suspected PJI in patients with multiple joint arthroplasties is controversial. Furthermore, no consensus exists regarding whether patients who have multiple joint arthroplasties and develop PJI in a single joint should be considered for prolonged antibiotic prophylaxis to reduce the risk of future infections. Finally, the optimal treatment of synchronous joint infections whether by débridement, antibiotics and implant retention, and one-stage or two-stage revision has not been defined. This review will summarize the best information available and provide pragmatic management strategies.

Risk Factors in Patients Who Had Prior Renal or Liver Transplant Undergoing Primary Total Knee Arthroplasty.

BACKGROUND: More solid organ transplant (SOT) patients are undergoing total knee arthroplasty (TKA). This study identifies risk factors for complications, implant survivorship, and mortality in TKA patients who had prior SOT. METHODS: We identified 176 TKAs in patients who had prior SOT. Of these, 77 had a prior renal (RT), 77 had a prior liver (LT) transplant, and 22 had multiple prior transplants (MT). Median survival was estimated using Kaplan-Meier. Univariate analyses were assessed with mixed-effects logistic regressions for complications and Cox-regressions for mortality. Median follow-up was 63 months (range, 24 to 109). RESULTS: At least one acute medical complication occurred in 25, 13, and 27% of cases with prior RT, LT, and MT, respectively (P = .12). None of the variables were significantly associated with acute medical complications. At least one surgical complication occurred in 14, 13 and 14% of cases with prior RT, LT, and MT, respectively (P = 1). Vitamin D supplementation (Odds Ratio [OR] = 0.38, P < .03) was associated with lower risk of surgical complications. Reoperation and revision rates were 5 and 3%, respectively. Older age at time of transplantation and greater level of serum creatinine at time of TKA were associated with lower risk (OR = 0.96, P = .01), and higher risk of reoperation (OR = 4.9, P = .01), respectively. Coronary artery disease was associated with higher mortality (Hazard Ratio = 2.35, P = .01). CONCLUSIONS: Vitamin D was associated with lower surgical complications, whereas a younger age at time of transplantation increased the risk of reoperation. Additionally, SOT patients with coronary artery disease demonstrated higher mortality after TKA.

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.

A Randomized Controlled Trial of Kinematically and Mechanically Aligned Total Knee Arthroplasties: Long-Term Follow-Up.

BACKGROUND: The optimal alignment technique for total knee arthroplasty (TKA) remains controversial. We previously reported 6-month and 2-year results of a randomized controlled trial comparing kinematically versus mechanically aligned TKA. In the present study, we report the mean 13-year (range, 12.6-14.4) follow-up results from this trial. METHODS: The original cohort included 88 TKAs (44 kinematically aligned using patient-specific guides and 44 mechanically aligned using conventional instrumentation), performed from 2008 to 2009. After institutional review board approval, the health records of the original 88 patients were queried. Revisions, reoperations, and complications were recorded. There were 26 patients who died, leaving 62 patients for follow-up. Of these, 48 patients (77%) were successfully contacted via phone. Reoperations and complications were documented. Furthermore, a battery of patient-reported outcome measures (PROMs) (including Western Ontario and McMaster University Index, Oxford Knee Score, Knee Injury and Osteoarthritis Outcome Score Junior, Forgotten Joint Score, Modified-Single Assessment Numerical Evaluation, and patient satisfaction) were obtained. RESULTS: Of the original 88 patients in the study, 15 patients had at least one reoperation (17%) and 5 patients had undergone complete revision surgery (6%). There was no difference between the 2 alignment methods for major and minor reoperations (P = .66). The kinematically aligned total knees self-reported a nonstatistically significant (P = .16) improved satisfaction (96% versus 82%), but no difference in other PROMs compared to mechanically aligned TKAs. CONCLUSION: Kinematically aligned TKA demonstrates excellent mean 13-year results, comparable to mechanically aligned TKA with similar reoperations, complications, and PROMs.

Changes Over a Decade in Patient-Reported Outcome Measures and Minimal Clinically Important Difference Reporting in Total Joint Arthroplasty.

Background: When used appropriately, the minimal clinically important difference (MCID) provides a powerful tool for identifying meaningful improvements brought about by a given treatment, offering more clinically relevant information than frequentist statistical analysis. However, recent studies have shown inconsistent derivation methods and use of MCIDs. The goal of this study was to report the rate of patient-reported outcome measures (PROMs) and MCIDs use in the literature and assess how this rate has changed over time. Methods: All articles published in 2010 and 2020 reporting on total hip arthroplasty or total knee arthroplasty in The Journal of Clinical Orthopaedics and Related Research, The Journal of Bone and Joint Surgery, and The Journal of Arthroplasty were reviewed. In each reviewed article, every reported PROM and, if present, its corresponding MCID was recorded. These data were used to calculate the rate of reporting of each PROM and MCID. Results: While the total number of articles on total hip arthroplasty and total knee arthroplasty reporting PROMs increased over time, the proportion of articles reporting PROMs decreased from 49.8% (131/263) in 2010 to 35.5% (194/546) in 2020 (P = .011). Of these articles that report PROMs, the proportion of articles reporting any MCID increased from 2.3% (3/131) in 2010 to 16.5% (32/194) in 2020 (P = .002). Conclusions: The rate of reporting of MCIDs among articles relating to total hip arthroplasty and total knee arthroplasty that report PROMs has increased significantly between 2010 and 2020 but remains low. Continued emphasis on appropriate inclusion and value of MCIDs when PROMS are reported in clinical outcomes studies is needed.

The Fate of the Inconclusive Periprosthetic Joint Infection Workup and Reliability of Data Points.

In 2018, periprosthetic joint infection (PJI) criteria were revised to include a new category labeled "inconclusive." The purpose of this study was to characterize and describe the fate of the inconclusive PJI workup and to analyze preoperative factors associated with outcomes. We reviewed all PJI workups at our institution during a 3-year period (426 patients). Patients were labeled "infected," "not infected," or "inconclusive" according to 2018 PJI preoperative criteria. In addition to standard diagnostic variables, the presence or absence of clinical elements that increase the pretest probability of infection were collected. Patients with any missing preoperative diagnostic test results and those with clinical follow-up less than 30 days were excluded. Logistic regression was used to identify the factors associated with infection. Two hundred ninety-six workups remained after exclusion criteria were applied, consisting of 66 (22.2%) with a preoperative score of 6 or greater defined as infected, 52 (17.6%) inconclusive (score 2-5), and 178 (60.1%) not infected (score 0-1). Postoperative re-scoring of the inconclusive group based on intraoperative findings as per the 2018 criteria identified 6 of 52 (11.5%) as infected, 12 (23.1%) inconclusive, and 34 (65.4%) not infected. Among those preoperatively scored as inconclusive, variables statistically correlated with the presence of infection included history of PJI, factors that increase skin barrier penetration (eg, psoriasis and venous stasis), and presence of comorbidities predisposing to infection. For patients labeled inconclusive, clinical elements of the pretest probability for infection (eg, history of prior PJI) were as reliable as any diagnostic test, including alpha-defensin, in the diagnosis of PJI. [Orthopedics. 2023;46(5):e291-e297.].

Routine Type and Screens Are Unnecessary in Primary Total Joint Arthroplasty: Follow-up After a Change in Practice.

Background: Routine type and screens (T&S) prior to total hip (THA) and total knee arthroplasty (TKA) are common despite low transfusion rates. Our institution implemented a practice change after previously demonstrating a transfusion rate of 1.06%. The purpose of this study is to present the follow-up data 1 year after the practice change of discontinuing routine T&S orders in primary total joint arthroplasty. Methods: A practice change was implemented discontinuing routine T&S orders prior to elective primary total joint arthroplasties. We retrospectively reviewed prospectively collected data on preoperative T&S, hemoglobin values, transfusion rates, bleeding disorders, and anticoagulation status. Results: A total of 663 patients were included in the study (273 THAs and 390 TKAs). The cumulative transfusion rate was 0.75. No patients received an intraoperative transfusion. Three patients (1.1%) received a postoperative transfusion after THA, and 3 patients (0.5%) received a transfusion after TKA. The mean preoperative hemoglobin in the transfused patients was 12.1 g/dL. Thirteen patients underwent a preoperative T&S (2.0%), and only 2 required transfusion (15.4%). Only 1 patient who required transfusion was on preoperative anticoagulation, and no patients with bleeding disorders required transfusions. Discontinuing routine T&S resulted in an estimated cost savings of $124,325.50. Conclusions: Discontinuation of routine T&S did not result in any adverse consequences. If required, T&S can safely be performed intraoperatively or postoperatively. Surgeons may consider obtaining a T&S if their preoperative hemoglobin is less than 11-12 g/dL or if significant blood loss is expected in a complex primary total joint arthroplasty.

There are Considerable Inconsistencies Among Minimum Clinically Important Differences in TKA: A Systematic Review.

BACKGROUND: Patient-reported outcome measures (PROMs) are frequently used to assess the impact of total knee arthroplasty (TKA) on patients. However, mere statistical comparison of PROMs is not sufficient to assess the value of TKA to the patient, especially given the risk profile of arthroplasty. Evaluation of treatment effect sizes is important to support the use of an intervention; this is often quantified with the minimum clinically important difference (MCID). MCIDs are unique to specific PROMs, as they vary by calculation methodology and study population. Therefore, a systematic review of calculated MCID values, their respective ranges, and assessment of their applications is important to guide and encourage their use as a critical measure of effect size in TKA outcomes research. QUESTIONS/PURPOSES: In this systematic review of MCID calculations and reporting in primary TKA, we asked: (1) What are the most frequently reported PROM MCIDs and their reported ranges in TKA? (2) What proportion of studies report distribution- versus anchor-based MCID values? (3) What are the most common methods by which these MCID values are derived for anchor-based values? (4) What are the most common derivation methods for distribution-based values? (5) How do the reported medians and corresponding interquartile ranges (IQR) compare between calculation methods for each PROM? METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review was conducted using the PubMed, EMBASE, and MEDLINE databases from inception through March 2022 for TKA articles reporting an MCID value for any PROMs. Two independent reviewers screened articles for eligibility, including any article that calculated new MCID values for PROMs after primary TKA, and extracted these data for analysis. Overall, 576 articles were identified, 38 of which were included in the final analysis. These studies had a total of 710,128 patients with a median age of 67.7 years and median BMI of 30.9 kg/m 2 . Women made up more than 50% of patients in most studies, and the median follow-up period was 17 months (range 0.25 to 72 months). The overall risk of bias was assessed as moderate using the Jadad criteria for one randomized controlled trial (3 of 5 ideal global score) and the modified Methodological Index for Non-randomized Studies criteria for comparative studies (mean 17.2 ± 1.8) and noncomparative studies (mean 9.6 ± 1.3). There were 49 unique PROMs for which 233 MCIDs were reported. Calculated values were classified as anchor-based, distribution-based, or not reported. MCID values for each PROM, MCID calculation method, number of patients, and study demographics were extracted from each study. Anchor-based and distribution-based MCIDs were compared for each unique PROM using a Wilcoxon rank sum test given non-normal distribution of values. RESULTS: The WOMAC Function and Pain subscores were the most frequently reported MCID value, comprising 9% (22 of 233) and 9% (22 of 233), respectively. The composite Oxford Knee Score (OKS) was the next most frequently reported (9% [21 of 233]), followed by the WOMAC composite score (6% [13 of 233]). The median anchor-based values for WOMAC Function and Pain subscores were 23 (IQR 16 to 33) and 25 (IQR 14 to 31), while the median distribution-based values were 11 (IQR 10.8 to 11) and 22 (IQR 17 to 23), respectively. The median anchor-based MCID value for the OKS was 6 (IQR 4 to 7), while the distribution-based value was 7 (IQR 5 to 10). Thirty-nine percent (15 of 38) used an anchor-based method to calculate a new MCID, while 32% (12 of 38) used a distribution-based technique. Twenty-nine percent of studies (11 of 38) calculated MCID values using both methods. For studies reporting an anchor-based calculation method, a question assessing patient satisfaction, pain relief, or quality of life along a five-point Likert scale was the most commonly used anchor (40% [16 of 40]), followed by a receiver operating characteristic curve estimation (25% [10 of 40]). For studies using distribution-based calculations, all articles used a measure of study population variance in their derivation of the MCID, with the most common method reported as one-half the standard deviation of the difference between preoperative and postoperative PROM scores (45% [14 of 31]). Most reported median MCID values (15 of 19) did not differ by calculation method for each unique PROM (p > 0.05) apart from the WOMAC Function component score and the Knee Injury and Osteoarthritis Outcome Score Pain and Activities of Daily Living subscores. CONCLUSION: Despite variability of MCIDs for each PROM, there is consistency in the methodology by which MCID values have been derived in published studies. Additionally, there is a consensus about MCID values regardless of calculation method across most of the PROMs we evaluated. CLINICAL RELEVANCE: Given their importance to treatment selection and patient safety, authors and journals should report MCID values with greater consistency. We recommend using a 7-point increase as the MCID for the OKS, consistent with the median reported anchor-based value derived from several high-quality studies with large patient groups that used anchor-based approaches for MCID calculation, which we believe are most appropriate for most applications in clinical research. Likewise, we recommend using a 10-point to 15-point increase for the MCID of composite WOMAC, as the median value was 12 (IQR 10 to 17) with no difference between calculation methods. We recommend use of median reported values for WOMAC function and pain subscores: 21 (IQR 15 to 33) and 23 (IQR 13 to 29), respectively.

Discordance Abounds in Minimum Clinically Important Differences in THA: A Systematic Review.

BACKGROUND: The minimum clinically important difference (MCID) is intended to detect a change in a patient-reported outcome measure (PROM) large enough for a patient to appreciate. Their growing use in orthopaedic research stems from the necessity to identify a metric, other than the p value, to better assess the effect size of an outcome. Yet, given that MCIDs are population-specific and that there are multiple calculation methods, there is concern about inconsistencies. Given the increasing use of MCIDs in total hip arthroplasty (THA) research, a systematic review of calculated MCID values and their respective ranges, as well as an assessment of their applications, is important to guide and encourage their use as a critical measure of effect size in THA outcomes research. QUESTIONS/PURPOSES: We systematically reviewed MCID calculations and reporting in current THA research to answer the following: (1) What are the most-reported PROM MCIDs in THA, and what is their range of values? (2) What proportion of studies report anchor-based versus distribution-based MCID values? (3) What are the most common methods by which anchor-based MCID values are derived? (4) What are the most common derivation methods for distribution-based MCID values? (5) How do the reported medians and corresponding ranges compare between calculation methods for each PROM? METHODS: The EMBASE, MEDLINE, and PubMed databases were systematically reviewed from inception through March 2022 for THA studies reporting an MCID value for any PROMs. Two independent authors reviewed articles for inclusion. All articles calculating new PROM MCID scores after primary THA were included for data extraction and analysis. MCID values for each PROM, MCID calculation method, number of patients, and study demographics were extracted from each article. In total, 30 articles were included. There were 45 unique PROMs for which 242 MCIDs were reported. These studies had a total of 1,000,874 patients with a median age of 64 years and median BMI of 28.7 kg/m 2 . Women made up 55% of patients in the total study population, and the median follow-up period was 12 months (range 0 to 77 months). The overall risk of bias was assessed as moderate using the modified Methodological Index for Nonrandomized Studies criteria for comparative studies (the mean score for comparative papers in this review was 18 of 24, with higher scores representing better study quality) and noncomparative studies (for these, the mean score was 10 of a possible 16 points, with higher scores representing higher study quality). Calculated values were classified as anchor-based, distribution-based, or not reported. MCID values for each PROM, MCID calculation method, number of patients, and study demographics were extracted from each study. Anchor-based and distribution-based MCIDs were compared for each unique PROM using a Wilcoxon rank sum test, given the non-normal distribution of values. RESULTS: The Oxford Hip Score (OHS) and the Hip Injury and Osteoarthritis Score (HOOS) Pain and Quality of Life subscore MCIDs were the most frequently reported, comprising 12% (29 of 242), 8% (20 of 242), and 8% (20 of 242), respectively. The EuroQol VAS (EQ-VAS) was the next-most frequently reported (7% [17 of 242]) followed by the EuroQol 5D (EQ-5D) (7% [16 of 242]). The median anchor-based value for the OHS was 9 (IQR 8 to 11), while the median distribution-based value was 6 (IQR 5 to 6). The median anchor-based MCID values for HOOS Pain and Quality of Life were 33 (IQR 28 to 35) and 25 (14 to 27), respectively; the median distribution-based values were 10 (IQR 9 to 10) and 13 (IQR 10 to 14), respectively. Thirty percent (nine of 30) of studies used an anchor-based method to calculate a new MCID, while 40% (12 of 30) used a distribution-based technique. Thirty percent of studies (nine of 30) calculated MCID values using both methods. For studies reporting an anchor-based calculation method, a question assessing pain relief, satisfaction, or quality of life on a five-point Likert scale was the most commonly used anchor (30% [eight of 27]), followed by a receiver operating characteristic curve estimation (22% [six of 27]). For studies using distribution-based calculations, the most common method was one-half the standard deviation of the difference between preoperative and postoperative PROM scores (46% [12 of 26]). Most reported median MCID values (nine of 14) did not differ by calculation method for each unique PROM (p > 0.05). The OHS, HOOS JR, and HOOS Function, Symptoms, and Activities of Daily Living subscores all varied by calculation method, because each anchor-based value was larger than its respective distribution-based value. CONCLUSION: We found that MCIDs do not vary very much by calculation method across most outcome measurement tools. Additionally, there are consistencies in MCID calculation methods, because most authors used an anchor question with a Likert scale for the anchor-based approach or used one-half the standard deviation of preoperative and postoperative PROM score differences for the distribution-based approach. For some of the most frequently reported MCIDs, however, anchor-based values tend to be larger than distribution-based values for their respective PROMs. CLINICAL RELEVANCE: We recommend using a 9-point increase as the MCID for the OHS, consistent with the median reported anchor-based value derived from several high-quality studies with large patient groups that used anchor-based approaches for MCID calculations, which we believe are most appropriate for most applications in clinical research. Likewise, we recommend using the anchor-based 33-point and 25-point MCIDs for the HOOS Pain and Quality of Life subscores, respectively. We encourage using anchor-based MCID values of WOMAC Pain, Function, and Stiffness subscores, which were 29, 26, and 30, respectively.

A Case Report of a Subdural Hematoma following Spinal Epidural prior to a Total Knee Arthroplasty.

Introduction: This case report adds to current literature on management of a subdural hematoma following total knee arthroplasty and is particularly important as joint replacement moves into outpatient surgery centers where the orthopedic surgery team becomes the sole patient contact point. Case Presentation. A 66-year-old male presented to the emergency department five days after elective robotic-assisted left total knee arthroplasty performed with spinal epidural with the symptoms of a persistent nonpostural headache. CT of the head revealed a small bifrontal acute subdural hematoma. He was admitted for overnight monitoring as a precaution. No vascular abnormalities or underlying pathology was found on further advanced imaging. He was discharged the following morning after follow-up CT showed no focal changes. Magnetic resonance imaging (MRI) one month later confirmed resolution of the subdural hematoma. Conclusion: Orthopedic surgeons should be aware of the signs and symptoms, as well as the risk factors for subdural hematomas following lumbar puncture, as it is a rare, but potentially life-threatening complication of spinal epidural.

Movement is Life-Optimizing Patient Access to Total Joint Arthroplasty: The Relationship Between Preoperative Optimization and Healthcare Disparities.

In coordination with Movement is Life, a multistakeholder coalition dedicated to promoting musculoskeletal health equity, the JAAOS Editorial Board has overseen the preparation of 12 articles that focus on methodology to optimize patients and improve access to total hip and knee arthroplasty for underserved populations.

Robotic-Assisted Total Knee Arthroplasty Allows for Trainee Involvement and Teaching Without Lengthening Operative Time.

BACKGROUND: Robot-assisted total knee arthroplasty (RA-TKA) is more accurate than mechanical total knee arthroplasty (M-TKA) and can provide real-time feedback about alignment and soft-tissue balancing that may be helpful in trainee education. However, both robotic-assist and trainee involvement potentially increase the surgical time. This study sought to evaluate whether RA-TKA procedures were longer than M-TKA procedures and whether trainee participation added additional surgical time. METHODS: This retrospective cohort study reviewed 220 consecutive primary TKAs (110 M-TKA and 110 RA-TKA) performed by an orthopedic trainee under supervision or performed by the consultant surgeon with an assistant present. For M-TKAs, a measured resection technique was used. For all RA-TKAs, the MAKO robotic system (Stryker, USA) was used. Tourniquet time was measured from inflation immediately prior to skin incision to deflation after placement of the final polyethylene insert. Procedures performed by a consulting surgeon with a surgical assist were used as controls for procedures performed by the trainee. In trainee-conducted procedures, the trainee is responsible for performing all critical aspects of the procedure while the consulting surgeon provides supervision and acts as first assist. RESULTS: 103 M-TKA and 96 RA-TKA were included. Tourniquet time was significantly longer for RA-TKAs vs M-TKAs (100 vs 89 minutes, P < .0001). However, there were no significant differences in tourniquet times between surgery performed by a trainee vs the consulting surgeon with surgical assist for either M-TKA (P = .3452) or RA-TKA (P = .6724). CONCLUSIONS: While RA-TKA takes longer, orthopedic trainees do not add additional time. Trainees at all stages of postgraduate learning can be educated in the use of robotic technology and potentially benefit from real-time feedback without further compromising surgical efficiency or increasing patient risk.