Racial and Ethnic Minorities Underrepresented in Pain Management Guidelines for Total Joint Arthroplasty: A Meta-analysis.

BACKGROUND: Total joint arthroplasty aims to improve quality of life and functional outcomes for all patients, primarily by reducing their pain. This goal requires clinical practice guidelines (CPGs) that equitably represent and enroll patients from all racial/ethnic groups. To our knowledge, there has been no formal evaluation of the racial/ethnic composition of the patient population in the studies that informed the leading CPGs on the topic of pain management after arthroplasty surgery. QUESTIONS/PURPOSES: Using papers included in the 2021 Anesthesia and Analgesia in Total Joint Arthroplasty Clinical Practice Guidelines and comparing them with US National census data, we asked: (1) What is the representation of racial/ethnic groups in randomized controlled trials compared with their representation in the US national population? (2) Is there a relationship between the reporting of racial/ethnic groups and year of data collection/publication, location of study, funding source, or guideline section? METHODS: Participant demographic data (study year published, study type, guideline section, year of data collection, study site, study funding, study size, gender, age, and race/ethnicity) were collected from articles cited by this guideline. Studies were included if they were full text, were primary research articles conducted primarily within the United States, and if they reported racial and ethnic characteristics of the participants. The exclusion criteria included duplicate articles, articles that included the same participant population (only the latest dated article was included), and the following article types: systematic reviews, nonsystematic reviews, terminology reports, professional guidelines, expert opinions, population-based studies, surgical trials, retrospective cohort observational studies, prospective cohort observational studies, cost-effectiveness studies, and meta-analyses. Eighty-two percent (223 of 271) of articles met inclusion criteria. Our original literature search yielded 27 papers reporting the race/ethnicity of participants, including 24 US-based studies and three studies conducted in other countries; only US-based studies were utilized as the focus of this study. We defined race/ethnicity reporting as the listing of participants' race or ethnicity in the body, tables, figures, or supplemental data of a study. National census information from 2000 to 2019 was then used to generate a representation quotient (RQ), which compared the representation of racial/ethnic groups within study populations to their respective demographic representation in the national population. An RQ value greater than 1 indicates an overrepresented group and an RQ value less than 1 indicates an underrepresented group, relative to the US population. Primary outcome measures of RQ value versus time of publication for each racial/ethnic group were evaluated with linear regression analysis, and race reporting and manuscript parameters were analyzed with chi-square analyses. RESULTS: Two US-based studies reported race and ethnicity independently. Among the 24 US-based studies reporting race/ethnicity, the overall RQ was 0.70 for Black participants, 0.09 for Hispanic participants, 0.1 for American Indian/Alaska Natives, 0 for Native Hawaiian/Pacific Islanders, 0.08 for Asian participants, and 1.37 for White participants, meaning White participants were overrepresented by 37%, Black participants were underrepresented by 30%, Hispanic participants were underrepresented by 91%, Asian participants were underrepresented by 92%, American Indian/Alaska Natives were 90% underrepresented, and Native Hawaiian Pacific Islanders were virtually not represented compared with the US national population. On chi-square analysis, there were differences between race/ethnicity reporting among studies with academic, industry, and dual-supported funding sources (χ2 = 7.449; p = 0.02). Differences were also found between race/ethnicity reporting among US-based and non-US-based studies (χ2 = 36.506; p < 0.001), with 93% (25 of 27) of US-based studies reporting race as opposed to only 7% (2 of 27) of non-US-based studies. Finally, there was no relationship between race/ethnicity reporting and the year of data collection or guideline section referenced. CONCLUSION: The 2021 Anesthesia and Analgesia in Total Joint Arthroplasty Clinical Practice Guidelines provide evidence-based recommendations that reflect the current standards in orthopaedic surgery, but the studies upon which they are based overwhelmingly underenroll and underreport racial/ethnic minorities relative to their proportions in the US population. As these factors impact analgesic administration, their continued neglect may perpetuate inequities in outcomes after TJA. CLINICAL RELEVANCE: Our study demonstrates that all non-White racial/ethnic groups were underrepresented relative to their proportion of the US population in the 2021 Anesthesia and Analgesia in Total Joint Arthroplasty Clinical Practice Guidelines, underscoring a weakness in the orthopaedic surgery evidence base and questioning the overall external validity and generalizability of these combined CPGs. An effort should be made to equitably enroll and report outcomes for all racial/ethnic groups in any updated CPGs.

Traumaplasty: When and How to Perform Acute Arthroplasty for Fractures Around the Hip in the Elderly Patient.

Acute fractures around the hip are prevalent injuries associated with potentially devastating outcomes. The growing utilization of arthroplasty for femoral neck fractures in the elderly is likely a result of improvements in reoperation rates and postoperative function. Compared to hemiarthroplasty, total hip arthroplasty is associated with a slight functional benefit that is unlikely noticeable for many patients, as well as minimal differences in complications and patient reported outcome measures. However, the evidence supporting cement use in femoral stem fixation is robust. Multiple high power randomized controlled trial-based studies indicate cement fixation brings more predictable outcomes and fewer reoperations. In the setting of acute acetabular fracture, total hip arthroplasty is a favorable approach for elderly patients and fracture patterns associated with increased risk of revision after open reduction and internal fixation. Variations in patient characteristics and fracture patterns demand careful consideration whenever selecting the optimal treatment. In fracture patient populations, comanagement is an important consideration when seeking to reduce complications and promote cost-effective quality care.

Underrepresentation of Non-White Participants in the American Academy of Orthopaedic Surgeons Guidelines for Surgical Management of Knee Osteoarthritis.

BACKGROUND: The aim of this study was to examine the racial and ethnic representation in studies included in the 2015 American Academy of Orthopaedic Surgeons Surgical Management of the Knee Evidence-Based Clinical Practice Guideline relative to their representation of the United States (US). METHODS: The demographic characteristics reported in articles included in the 2015 American Academy of Orthopaedic Surgeons Surgical Management of the Knee Evidence-Based Clinical Practice Guideline were analyzed. The primary outcome of interest was the representation quotient, which is the ratio of the proportion of a racial/ethnic group in the guideline studies relative to their proportion in the US. There were 211 studies included, of which 15 (7%) reported race. There were 35 studies based in the US and 7 of the US-based studies reported race. RESULTS: No US-based studies reported race and ethnicity separately, no studies reported American Indian/Alaska Native participants and no US-based studies reported Asian participants. The representation quotient of US-based studies was 0.66 for Black participants, 0.33 for Hispanic participants, and 1.30 for White participants, which indicates a relative over-representation of White participants compared to national proportions. CONCLUSION: This study illustrated that the evidence base for the surgical management of knee osteoarthritis has been constructed from studies which fail to consider race and ethnicity. Of those US-based studies which do report race or ethnicity, study cohorts do not reflect the US population. These results illustrate a disparity in clinical orthopedic surgical evidence and highlight the need for improved research recruitment strategies.

Quantifying Patient Expectations for Total Knee Arthroplasty: Expectations for Improvement Are Greater Than Minimal Clinically Important Difference.

BACKGROUND: Achieving a minimal clinically important difference (MCID) in patient-reported outcomes following total knee arthroplasty (TKA) is common, yet up to 20% patient dissatisfaction persists. Unmet expectations may explain post-TKA dissatisfaction. No prior studies have quantified patient expectations using the same patient-reported outcome metric as used for MCID to allow direct comparison. METHODS: This was a prospective study of patients undergoing TKA with 5 fellowship-trained arthroplasty surgeons at one academic center. Baseline Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) domains were assessed. Expected PROMIS scores were determined by asking patients to indicate the outcomes they were expecting at 12 months postoperatively. Predicted scores were generated from a predictive model validated in the Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR) dataset. T-tests were used to compare baseline, expected, and predicted PROMIS scores. Expected scores were compared to PROMIS MCID values obtained from the literature. Regression models were used to identify patient characteristics associated with high expectations. RESULTS: There were 93 patients included. Mean age was 67 years (range, 30 to 85) and 55% were women. Mean baseline PROMIS PF and PI was 34.4 ± 6.7 and 62.2 ± 6.4, respectively. Patients expected significant improvement for PF of 1.9 times the MCID (MCID = 11.3; mean expected improvement = 21.6, 95% confidence interval [CI] 19.6 to 23.5, P < .001) and for PI of 2.3 times the MCID (MCID = 8.9; mean expected improvement = 20.6, 95% CI 19.1-22.2, P < .001). Predicted scores were significantly lower than expected scores (mean difference = 9.5, 95% CI 7.7 to 11.3, P < .001). No unique patient characteristics were associated with high expectations (P > .05). CONCLUSIONS: To our knowledge, this study is the first to quantify preoperative patient expectations using the same metric as MCID to allow for direct comparison. Patient expectations for improvement following TKA are ∼2× greater than MCID and are significantly greater than predicted outcome scores. This discrepancy challenges currently accepted standards of success after TKA and indicates a need for improved expectation setting prior to surgery.

2023 American College of Rheumatology and American Association of Hip and Knee Surgeons Clinical Practice Guideline for the Optimal Timing of Elective Hip or Knee Arthroplasty for Patients With Symptomatic Moderate-to-Severe Osteoarthritis or Advanced Symptomatic Osteonecrosis With Secondary Arthritis for Whom Nonoperative Therapy Is Ineffective.

OBJECTIVE: To develop evidence-based consensus recommendations for the optimal timing of hip and knee arthroplasty to improve patient-important outcomes including, but not limited to, pain, function, infection, hospitalization, and death at 1 year for patients with symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis of the hip or knee who have previously attempted nonoperative therapy, and for whom nonoperative therapy was ineffective, and who have chosen to undergo elective hip or knee arthroplasty (collectively referred to as TJA). METHODS: We developed 13 clinically relevant population, intervention, comparator, outcomes (PICO) questions. After a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the quality of evidence (high, moderate, low, or very low), and evidence tables were created. A Voting Panel, including 13 physicians and patients, discussed the PICO questions until consensus was achieved on the direction (for/against) and strength (strong/conditional) of the recommendations. RESULTS: The panel conditionally recommended against delaying TJA to pursue additional nonoperative treatment including physical therapy, nonsteroidal antiinflammatory drugs, ambulatory aids, and intraarticular injections. It conditionally recommended delaying TJA for nicotine reduction or cessation. The panel conditionally recommended delay for better glycemic control for patients who have diabetes mellitus, although no specific measure or level was identified. There was consensus that obesity by itself was not a reason for delay, but that weight loss should be strongly encouraged, and the increase in operative risk should be discussed. The panel conditionally recommended against delay in patients who have severe deformity or bone loss, or in patients who have a neuropathic joint. Evidence for all recommendations was graded as low or very low quality. CONCLUSION: This guideline provides evidence-based recommendations regarding the optimal timing of TJA in patients who have symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis for whom nonoperative therapy was ineffective to improve patient-important outcomes, including pain, function, infection, hospitalization, and death at 1 year. We acknowledge that the evidence is of low quality primarily due to indirectness and hope future research will allow for further refinement of the recommendations.

Caring for Diverse and High-Risk Patients: Surgeon, Health System, and Patient Integration.

Access and outcome disparities exist in hip and knee arthroplasty care. These disparities are associated with race, ethnicity, and social determinants of health such as income, housing, transportation, education, language, and health literacy. Additionally, medical comorbidities affecting postoperative outcomes are more prevalent in underresourced communities, which are more commonly communities of color. Navigating racial and ethnic differences in treating our patients undergoing hip and knee arthroplasty is necessary to reduce inequitable care. It is important to recognize our implicit biases and lessen their influence on our healthcare decision-making. Social determinants of health need to be addressed on a large scale as the current inequitable system disproportionally impacts communities of color. Patients with lower health literacy have a higher risk of postoperative complications and poor outcomes after hip and knee replacement. Low health literacy can be addressed by improving communication, reducing barriers to care, and supporting patients in their efforts to improve their own health. High-risk patients require more financial, physical, and mental resources to care for them, and hospitals, surgeons, and health insurance companies are often disincentivized to do so. By advocating for alternative payment models that adjust for the increased risk and take into account the increased perioperative work needed to care for these patients, surgeons can help reduce inequities in access to care. We have a responsibility to our patients to recognize and address social determinants of health, improve the diversity of our workforce, and advocate for improved access to care to decrease inequity and outcomes disparities in our field.

The Impact of Race and Socioeconomic Status on Total Joint Arthroplasty Care.

BACKGROUND: Racial minorities and patients from lower socioeconomic backgrounds are less likely to undergo total joint arthroplasty (TJA) for degenerative joint disease (DJD). However, when these patients do present for care, little is known about the overall severity of DJD and surgical wait times. METHODS: A retrospective cohort of 407 patients (131 black and 276 white) who presented to an arthroplasty clinic and went on to receive TJA was established. Severity of osteoarthritis was assessed radiographically via Kellgren-Lawrence (KL) grade. Preoperative Knee Society Score (KSS) and Harris Hip Score (HHS) were used to measure joint pain and function. Multivariate regression modeling and analysis of covariance were used to examine racial and socioeconomic differences in KL grade, KSS, HHS, and time to surgery. RESULTS: Black patients presented with significantly greater KL scores than white patients (P = .046, odds ratio = 1.65, 95% confidence interval [1.01, 2.70]). In contrast, there were no statistically significant racial differences in the mean preoperative KSS (P = .61) or HHS (P = .69). Black patients were also found to wait, on average, 35% longer for TJA (P = .03, hazard ratio = 1.35, 95% confidence interval [1.04, 1.75]). Low income was associated with higher KL grade (P = .002), lower KSS (P = .07), and lower HHS (P = .001). CONCLUSION: Despite presenting with more advanced osteoarthritis, black patients reported similar levels of joint dysfunction and had longer surgical wait times when compared with white patients. Lower socioeconomic status was similarly associated with more severe DJD.

Disparities in Hip Arthroplasty Outcomes: Results of a Statewide Hospital Registry From 2016 to 2018.

BACKGROUND: In November 2019, Centers for Medicare and Medicaid Services announced total hip arthroplasty (THA) will be removed from the inpatient-only list. This may lead to avoidance of patients who have prolonged hospitalizations and discharge to skilled nursing facilities or push providers to unsafely push patients to outpatient surgery centers. Disparities in hip arthroplasty may worsen as patients are "risk stratified" preoperatively to minimize cost outliers. We aimed to evaluate which patient characteristics are associated with extended length of stay (eLOS)-greater than 2 days-and nonhome discharge in patients undergoing hip arthroplasty. METHODS: The Illinois COMPdata administrative database was queried for THA admissions from January 2016 to June 2018. Variables included age, sex, race and ethnicity, median household income, Illinois region, insurance status, principal diagnosis, Charlson comorbidity index, obesity, discharge disposition, and LOS. Hospital characteristics included bundled payment participation and arthroplasty volume. Using multiple Poisson regression, we examined the association between these factors and the likelihood of nonhome discharge and eLOS. RESULTS: There were 41,832 THA admissions from January 2016 to June 2018. A total of 36% had LOS greater than 2 midnights and 25.3% of patients had nonhome discharges. Female patients, non-Hispanic black patients, patients older than 75, obese patients, Medicaid or uninsured status, Charlson comorbidity index > 3, and hip arthroplasty for fracture were associated with increased risk of eLOS and/or nonhome discharge (P < .05). CONCLUSION: With the Centers for Medicare and Medicaid Services emphasis on cost containment, patients at risk of extended stay or nonhome discharge may be deemed "high risk" and have difficulty accessing arthroplasty care. These are potentially vulnerable groups during the transition to the bundled payment model.

What Are the Risk Factors for 48 or More-Hour Stay and Nonhome Discharge After Total Knee Arthroplasty? Results From 151 Illinois Hospitals, 2016-2018.

BACKGROUND: Bundled payment programs and the Centers for Medicare and Medicaid Services removal of total knee arthroplasty (TKA) from the inpatient-only list potentially incentivize avoiding patients with extended length of stay (eLOS) and nonhome discharge (NHD). We aimed to describe which patients are most at risk of eLOS (>2 days), very eLOS (veLOS; >4 days), and NHD. METHODS: Admissions for unilateral TKAs at 151 Illinois nonfederal hospitals from January 2016 to June 2018 were selected from the Illinois Hospital and Health Systems Association COMPdata administrative hospital discharge database. Records included patient age, race and ethnicity, Illinois region, insurance status, principal diagnosis, and date of procedure. Zip code level median household income, Charlson comorbidity index, and obesity status were computed. Hospitals were characterized through their bundled payment participation status, academic status, and annual knee replacement volume. Poisson regression was used to test the associations between patient and hospital characteristics and the likelihood of eLOS, veLOS, and NHD. RESULTS: Of the 72,359 admissions included, 25.0% had an NHD, 41.1% had eLOS, and 4.0% veLOS. Female patients, those 75 years old or more as compared to those 65-74 years old, non-Hispanic blacks, Hispanics and Asians versus non-Hispanic whites, Medicaid/uninsured patients versus those privately insured, obese patients, those with nonzero Charlson comorbidity index, and those treated at low-volume hospitals (<200 TKAs/year vs >600 TKAs/year) were more likely to have eLOS, veLOS, and/or NHD (P < .05). CONCLUSION: Arthroplasty surgeons may be incentivized to avoid the abovementioned patient groups due to bundled payment programs and recent Centers for Medicare and Medicaid Services legislation.

Current Approach to the Management of Forearm and Elbow Dislocations in Children.

Pediatric orthopedic injuries are a common reason for presentation to the emergency department. This article sequentially discusses 2 important upper extremity injuries that require prompt management in the emergency department. Radial head subluxations are discussed with a focus on current evidence for imaging, reduction techniques, and follow-up. Elbow dislocations, although less common than radial head subluxations, are also addressed, highlighting imaging, reduction, immobilization, and follow-up recommendations.

The Interaction of Obesity and Metabolic Syndrome in Determining Risk of Complication Following Total Joint Arthroplasty.

BACKGROUND: The arthroplasty population is increasingly comorbid, and current quality improvement initiatives demand accurate risk stratification. Metabolic syndrome (MetS) has been identified as a risk factor for adverse events after arthroplasty; however, its interaction with obesity in contributing to risk is unclear. METHODS: A retrospective analysis of all Medicare patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) at a single institution from 2009 to 2013 investigated the interaction between MetS, body mass index (BMI), and risk for Centers for Medicare and Medicaid Services (CMS)-reportable complications, readmission, and discharge disposition. RESULTS: A total of 1462 patients (942 TKA, 538 THA) were included, of which 16.2% had MetS. Regression analysis found that MetS was significantly related to risk of CMS complications (odds ratio [OR] = 1.96, 95% confidence interval [CI] 1.16-3.31, P = .012) and nonhome discharge (OR = 1.78, 95% CI 1.39-2.27, P < .001), but not readmission (OR = 1.23, 95% CI 0.7-2.18, P = .485). Within the MetS cohort, increasing BMI was not associated with increasing complications (P = .726) or readmissions (P = .206) but was associated with nonhome discharge (OR = 1.191 per unit increase in BMI, 95% CI 1.038-1.246, P = .001). CONCLUSION: MetS increases risk for CMS-reportable complications and nonhome discharge disposition after THA and TKA regardless of BMI. Obesity is of less value than MetS in assessing overall risk for complication after THA and TKA.

Perioperative Outcomes Following Unilateral Versus Bilateral Total Knee Arthroplasty.

Simultaneous bilateral total knee arthroplasty (SB-TKA) is potentially a cost saving manner of caring for patients with bilateral symptomatic knee arthritis. We performed a retrospective analysis using the 2010-2012 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) to evaluate the risk of perioperative complication following SB-TKA. Demographic characteristics, comorbidities, and 30-day complication rates were studied using a propensity score-matched analysis comparing patients undergoing unilateral TKA and SB-TKA. A total of 4489 patients met the inclusion criteria, of which 973 were SB-TKA. SB-TKA was associated with increased overall complications (P = 0.023), medical complications (P = 0.002) and reoperation (OR 2.12, P = 0.020). Further, total length of hospital stay (4.0 vs 3.4 days, P < 0.001) was significantly longer following bilateral surgery.

Can the American College of Surgeons Risk Calculator Predict 30-Day Complications After Knee and Hip Arthroplasty?

Accurate risk stratification of patients undergoing total hip (THA) and knee (TKA) arthroplasty is essential in the highly scrutinized world of pay-for-performance, value-driven healthcare. We assessed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) surgical risk calculator's ability to predict 30-day complications using 1066 publicly-reported Medicare patients undergoing primary THA or TKA. Risk estimates were significantly associated with complications in the categories of any complication (P = .005), cardiac complication (P < .001), pneumonia (P < .001) and discharge to skilled nursing facility (P < .001). However, predictability of complication occurrence was poor for all complications assessed. To facilitate the equitable provision and reimbursement of patient care, further research is needed to develop accurate risk stratification tools in TKA and THA surgery.

Imageless robotic total knee arthroplasty determines similar coronal plane alignment of the knee (CPAK) parameters to long leg radiographs.

BACKGROUND: The coronal plane alignment of the knee (CPAK) classification was first developed using long leg radiographs (LLR) and has since been reported using image-based and imageless robotic total knee arthroplasty (TKA) systems. However, the correspondence between imageless robotics and LLR-derived CPAK parameters has yet to be investigated. This study therefore examined the differences in CPAK parameters determined with LLR and imageless robotic navigation using either generic or optimized cartilage wear assumptions. METHODS: Medial proximal tibial angle (MPTA) and lateral distal femoral angle (LDFA) were determined from the intraoperative registration data of 61 imageless robotic TKAs using either a generic 2 mm literature-based wear assumption (Navlit) or an optimized wear assumption (Navopt) found using an error minimization algorithm. MPTA and LDFA were also measured from preoperative LLR by two observers and intraclass correlation coefficients (ICCs) were calculated. MPTA, LDFA, joint line obliquity (JLO), and arithmetic hip-knee-ankle angle (aHKA) were compared between the robotic and the average LLR measurements over the two observers. RESULTS: ICCs between observers for LLR were over 0.95 for MPTA, LDFA, JLO, and aHKA, indicating excellent agreement. Mean CPAK differences were not significant between LLR and Navlit (all differences within 0.6°, P > 0.1) or Navopt (all within 0.1°, P > 0.83). Mean absolute errors (MAE) between LLR and Navlit were: LDFA = 1.4°, MPTA = 2.0°, JLO = 2.1°, and aHKA = 2.7°. Compared to LLR, the generic wear classified 88% and the optimized wear classified 94% of knees within one CPAK group. Bland-Altman comparisons reported good agreement for LLR vs. Navlit and Navopt, with > 95% and > 91.8% of measurements within the limits of agreement across all CPAK parameters, respectively. CONCLUSIONS: Imageless robotic navigation data can be used to calculate CPAK parameters for arthritic knees undergoing TKA with good agreement to LLR. Generic wear assumptions determined MPTA and LDFA with MAE within 2° and optimizing wear assumptions showed negligible improvement.

Agreement of the American Academy of Orthopaedic Surgeons Appropriate Use Criteria With Treatment Recommendations From Arthroplasty Surgeons.

Background: The American Academy of Orthopaedic Surgeons (AAOS) Appropriate Use Criteria (AUC) for Surgical Management of Osteoarthritis of the Knee (2016) and Management of Osteoarthritis of the Hip (2017) are intended to provide treatment recommendations for osteoarthritis (OA). This study examined the agreement of AUC appropriateness classifications with arthroplasty surgeon recommendations for total knee arthroplasty (TKA) and total hip arthroplasty (THA). Methods: The cohort included 558 OA patients (397 knee, 161 hip) referred to a specialty arthroplasty clinic. Surgeons completed the online AAOS AUC patient profiles to generate appropriateness ratings. Surgeons' recommendations for treatment were recorded. We performed univariate and bivariate analyses to evaluate relationships between AUC appropriateness and surgeon recommendations. Results: The knee OA AUC classified TKA as "appropriate" for 309 (77.8%) of the 397 knee OA patients. Surgeons recommended TKA for 123 (31.0%), resulting in 46.8% (n = 186) higher rate of "appropriate" classification by AUC than TKA recommendation by surgeons. Weighted Cohen's κ demonstrated slight agreement (κ = 0.06, 95% confidence interval: 0.04, 0.09) between AUC appropriateness and surgeon TKA recommendation. The hip OA AUC classified THA as "appropriate" for 98 (60.9%) of the 161 hip OA patients. Surgeons recommended THA for 76 (47.2%), resulting in 13.7% (n = 22) higher rate of "appropriate" classification by AUC than THA recommendation by surgeons. Weighted Cohen's κ demonstrated moderate agreement (κ = 0.47, 95% confidence interval: 0.37, 0.57) between the AUC appropriateness classification and the surgeon's THA recommendation. Conclusions: AAOS AUC guidelines indicated surgical appropriateness significantly more than arthroplasty surgeons. AUC agreed slightly with surgeons for TKA and moderately for THA.

Laxity, Balance, and Alignment of a Simulated Kinematic Alignment Total Knee Arthroplasty.

Background: Kinematic alignment (KA) and related personalized alignment strategies in total knee arthroplasty (TKA) target restoration of native joint line obliquity and alignment. In practice, deviations from exact restoration of the prearthritic joint surface are tolerated for either the femur or tibia to achieve ligamentous balance. It remains unknown what laxity, balance, and alignment would result if a pure resurfacing of both femur and tibia were performed in a KA TKA technique. Methods: We used data from 382 robot-assisted TKA performed with a digital joint tensioner to simulate TKA with a pure resurfacing KA technique for both femur and tibia. All knees had the posterior cruciate ligament retained. Knees were subdivided into 4 groups based on preoperative coronal alignment: valgus, neutral, varus, and high varus. Medial and lateral laxity in extension and flexion, balance in extension and flexion, and coronal plane alignment were compared between groups using analysis of variance testing. Results: In simulated pure resurfacing KA TKA across a range of preoperative coronal plane deformities, only 11%-31% of knees would have mediolateral extension ligament balance within ±1 mm, and 20%-41% would have a medial flexion gap that is looser than the lateral flexion gap. Over 45% of knees would have coronal hip-knee-ankle angle >3 degrees from mechanical neutral. Conclusions: In simulations of pure resurfacing KA TKA, there was wide variability in the resulting laxity and alignment outcomes. Most knees had alignment and balance outcomes outside of normally accepted ranges. Techniques that deviate from pure resurfacing in order to achieve balance appear favorable.