Are current rates of uncemented fixation in total hip arthroplasty supported by the literature? An update on the uncemented paradox.

The optimal fixation method in total hip arthroplasty (THA) remains controversial. Initial concerns related to the long-term performance of cement fixation as well as cement disease led to the development of cementless implants, and registry data has indicated that the use of this type of fixation has increased in recent years. However, data from these same registries has not shown any improvement in outcomes when compared to cement fixation. On the contrary, while similar outcomes are seen when comparing these fixation types in younger patients (<70 years of age), cementless fixation has shown increased implant failure and revision rates in elderly patients (>70 years of age). Given the increased projected volume of THA in the United States over the next decade, it is important to utilise available data to make clinical decisions that minimise not only individual patient harm, but also the burden on the healthcare system itself. This review provides an overview of currently available outcomes data comparing cement and cementless fixation, as well as an updated analysis of current trends in fixation use in THA. We furthermore provide a comprehensive technique guide to help surgeons optimise cement fixation of the femoral component for THA and hemiarthroplasty.

Assessing Ability for ChatGPT to Answer Total Knee Arthroplasty-Related Questions.

BACKGROUND: Artificial intelligence in the field of orthopaedics has been a topic of increasing interest and opportunity in recent years. Its applications are widespread both for physicians and patients, including use in clinical decision-making, in the operating room, and in research. In this study, we aimed to assess the quality of ChatGPT answers when asked questions related to total knee arthroplasty. METHODS: ChatGPT prompts were created by turning 15 of the American Academy of Orthopaedic Surgeons Clinical Practice Guidelines into questions. An online survey was created, which included screenshots of each prompt and answers to the 15 questions. Surgeons were asked to grade ChatGPT answers from 1 to 5 based on their characteristics: (1) relevance, (2) accuracy, (3) clarity, (4) completeness, (5) evidence-based, and (6) consistency. There were 11 Adult Joint Reconstruction fellowship-trained surgeons who completed the survey. Questions were subclassified based on the subject of the prompt: (1) risk factors, (2) implant/intraoperative, and (3) pain/functional outcomes. The average and standard deviation for all answers, as well as for each subgroup, were calculated. Inter-rater reliability (IRR) was also calculated. RESULTS: All answer characteristics were graded as being above average (ie, a score > 3). Relevance demonstrated the highest scores (4.43 ± 0.77) by surgeons surveyed, and consistency demonstrated the lowest scores (3.54 ± 1.10). ChatGPT prompts in the Risk Factors group demonstrated the best responses, while those in the Pain/Functional Outcome group demonstrated the lowest. The overall IRR was found to be 0.33 (poor reliability), with the highest IRR for relevance (0.43) and the lowest for evidence-based (0.28). CONCLUSIONS: ChatGPT can answer questions regarding well-established clinical guidelines in total knee arthroplasty with above-average accuracy but demonstrates variable reliability. This investigation is the first step in understanding large language model artificial intelligence like ChatGPT and how well they perform in the field of arthroplasty.

Total Hip Arthroplasty is the Most Effective Treatment for Atraumatic Subchondral Insufficiency Fractures of the Femoral Head.

BACKGROUND: Subchondral insufficiency fracture of the femoral head (SIFH) is a relatively newly used diagnosisfollowing an insidious onset of hip pain in individuals without apparent antecedent trauma. The aim of this study was to investigate the outcomes of a consecutive series of patients with SIFH treated at one institution. METHODS: A total of 93 patients aged 23 to 91 years who were treated for SIFH in the outpatient clinics at one academic, urban medical center between August 2012 and August 2019 were identified. The diagnosis was made by magnetic resonance imaging or radiograph of the hip and was confirmed by a radiologist specialized in orthopedic surgery. Patient demographics, injury history, duration of pain, treatment type, and persistence of pain were recorded. RESULTS: Sixty-five (69.9%) patients with a mean age of 64.2 ± 9.4 years ultimately underwent total hip arthroplasty (THA). Twenty-eight (30.1%) patients chose no surgical intervention. Patients who underwent THA had less pain at their final follow-up appointment than patients who elected non-operative treatment (p < 0.001). At their final follow-up appointments, 92.9% of patients treated non-operatively reported pain, compared to only 13.8% of patients who underwent THA who had pain. Age, body mass index, and duration of pain prior to initial complaint did not affect presence of continued pain at final follow-up appointments, regardless of treatment type (p > 0.05). CONCLUSION: In the majority of patients, SIFH is often not sufficiently managed with non-operative treatments. Pain reported among patients with confirmed or suspected SIFH is usually severe and interferes with patients' ability to perform their activities of daily life. Total hip arthroplasty seems to be the most reliable method of treatment for this condition. Physicians who treat patients with SIFH should counsel them as to the expectations of recovery and the potential for poorer outcome if treated without THA.

The Effect of Surgeon and Hospital Volume on Total Knee Arthroplasty Patient-reported Outcome Measures: An American Joint Replacement Registry Study.

BACKGROUND: The lower morbidity and mortality rate associated with increased surgeon and hospital volume may also correlate with improved patient-reported outcome measures. The goal of this study was to determine the relationship between surgeon and hospital volume and patient-reported outcome measures after total knee arthroplasty (TKA) using American Joint Replacement Registry data. METHODS: Using American Joint Replacement Registry data from 2012 to 2020, 8,193 primary, elective TKAs with both preoperative and 1-year postoperative The Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS-JR) scores were analyzed. This study was powered to detect the minimally clinical important difference (MCID). The main exposure variables were median annual surgeon and hospital volume. Tertiles were formed based on the median annual number of TKAs performed: low-volume surgeons (1 to 52), medium-volume (53 to 114), and high-volume (≥115); low-volume hospitals (1 to 283), medium-volume (284 to 602), and high-volume (≥603). The mean preoperative and 1-year postoperative KOOS-JR were compared. Multivariable logistic regression models were used to determine the effect of surgeon and hospital volume and demographics on achieving the MCID for KOOS-JR. RESULTS: The mean preoperative and 1-year postoperative KOOS-JR score for low-volume surgeons was 47.78 ± 13.50 and 77.75 ± 16.65, respectively, and 47.32 ± 13.73 and 76.86 ± 16.38 for low-volume hospitals. The mean preoperative and 1-year postoperative KOOS-JR score for medium-volume surgeons was 47.20 ± 13.46 and 76.70 ± 16.98, and 48.93 ± 12.50 and 77.15 ± 16.36 for medium-volume hospitals. The mean preoperative and 1-year postoperative KOOS-JR scores for high-volume surgeons were 49.08 ± 13.04 and 78.23 ± 16.72, and 48.11 ± 13.47 and 78.23 ± 17.22 for high-volume hospitals. No notable difference was observed in reaching MCID for KOOS-JR after adjustment for potential confounders. CONCLUSION: An increased number of TKA cases performed by a given surgeon or at a given hospital did not have an effect on achieving MCID for KOOS-JR outcomes.

Chronic Lower Back Pain in Weight Lifters: Epidemiology, Evaluation, and Management.

¼ Chronic lower back pain (LBP) is common in both nonathletes and weight lifters, but the diagnosis and treatment should be approached differently in these 2 populations based on the unique movement patterns causing the pain.¼ Injury rates of weight lifters are far less than those of contact sports, ranging from 1.0 to 4.4 injuries per 1,000 workout hours. However, the lower back was consistently one of the top 2 injury sites for weight lifters, accounting for anywhere from 23% to 59% of all injuries. LBP was most often associated with the squat or deadlift.¼ Guidelines for evaluating general LBP are applicable to weight lifters, including a thorough history and physical examination. However, the differential diagnosis will change based on the patient's lifting history. Of the many etiologies of back pain, weight lifters are most likely to be diagnosed with muscle strain or ligamentous sprain, degenerative disk disease, disk herniation, spondylolysis, spondylolisthesis, or lumbar facet syndrome.¼ Traditional recommended therapies include nonsteroidal anti-inflammatory drugs, physical therapy, and activity modification, which are often insufficient to resolve pain and prevent injury recurrence. Because most athletes will want to continue to lift weights, lifting-specific behavior modifications focused on improved technique and correcting mobility and muscular imbalances are important aspects of management in this patient population.

Pain-management protocol aimed at reducing opioids following total knee arthroplasty does not negatively impact patient satisfaction.

BACKGROUND: Prior research has demonstrated that the prescription of opioid medications may be associated with the desire to treat pain in order to achieve favorable patient satisfaction. The purpose of the current study was to investigate the effect of decreased opioid prescribing following total knee arthroplasty (TKA) on survey-administered patient satisfaction scores. METHOD: This study is a retrospective review of prospectively collected survey data for patients who underwent primary elective TKA for the treatment of osteoarthritis (OA) between September 2014 and June 2019. All patients included had completed Hospital Consumer Assessment of Healthcare Providers and Systems (HCAPS) survey information. Patients were stratified into two cohorts based on whether their surgery took place prior to or subsequent to the implementation of an institutional-wide opioid-sparing regimen. RESULTS: Of the 613 patients included, 488 (80%) were in the pre-protocol cohort and 125 (20%) in the post-protocol cohort. Rate of opioid refills (33.6% to 11.2%; p < 0.001) as well as length of stay (LOS, 2.40 ± 1.05 to 2.13 ± 1.13 days; p = 0.014) decreased significantly after protocol change while rate of current smokers increased significantly (4.1% to 10.4%; p = 0.011). No significant difference was observed in "top box" percentages for satisfaction with pain control (Pre: 70.5% vs Post: 72.8%; p = 0.775). CONCLUSIONS: Protocols calling for reduced prescription of opioids following TKA resulted in significantly lower rates of opioid refills, and were associated with significantly shorter LOS, while causing no statistically significant deleterious changes in patient satisfaction, as measured by HCAPS survey. LOE: III. CLINICAL RELEVANCE: This study suggests that HCAPS scores are not negatively impacted by a reduction in postoperative opioid analgesics.

Trends in Revision Total Hip Arthroplasty Cost, Revenue, and Contribution Margin 2011 to 2021.

BACKGROUND: Revision total hip arthroplasty (rTHA) is a costly procedure, and its prevalence has been steadily increasing over time. This study aimed to examine trends in hospital cost, revenue, and contribution margin (CM) in patients undergoing rTHA. METHODS: We retrospectively reviewed all patients who underwent rTHA from June 2011 to May 2021 at our institution. Patients were stratified into groups based on insurance coverage: Medicare, government-managed Medicaid, or commercial insurance. Patient demographics, revenue (any payment the hospital received), direct cost (any cost associated with the surgery and hospitalization), total cost (the sum of direct and indirect costs), and CM (the difference between revenue and direct cost) were collected. Changes over time as a percentage of 2011 numbers were analyzed. Linear regression analyses were used to determine the overall trend's significance. Of the 1,613 patients identified, 661 were covered by Medicare, 449 by government-managed Medicaid, and 503 by commercial insurance plans. RESULTS: Medicare patients exhibited a significant upward trend in revenue (P < .001), total cost (P = .004), direct cost (P < .001), and an overall downward trend in CM (P = .037), with CM for these patients falling to 72.1% of 2011 values by 2021. CONCLUSION: In the Medicare population, reimbursement for rTHA has not matched increases in cost, leading to considerable reductions in CM. These trends affect the ability of hospitals to cover indirect costs, threatening access to care for patients who require this necessary procedure. Reimbursement models for rTHA should be reconsidered to ensure the financial feasibility of these procedures for all patient populations.

Larger operating rooms have better air quality than smaller rooms in primary total knee arthroplasty.

INTRODUCTION: Operating room air quality can be affected by several factors including temperature, humidity, and airborne particle burden. Our study examines the role of operating room (OR) size on air quality and airborne particle (ABP) count in primary total knee arthroplasty (TKA). MATERIALS AND METHODS: We analyzed all primary, elective TKAs performed within two ORs measuring 278 sq ft. (small) and 501 sq ft. (large) at a single academic institution in the United States from April 2019 to June 2020. Intraoperative measurements of temperature, humidity, and ABP count were recorded. p values were calculated using t test for continuous variables and chi-square for categorical values. RESULTS: 91 primary TKA cases were included in the study, with 21 (23.1%) in the small OR and 70 (76.9%) in the large OR. Between-groups comparisons revealed significant differences in relative humidity (small OR 38.5% ± 7.24% vs. large OR 44.4% ± 8.01%, p = 0.002). Significant percent decreases in ABP rates for particles measuring 2.5 µm (- 43.9%, p = 0.007) and 5.0 µm (- 69.0%, p = 0.0024) were found in the large OR. Total time spent in the OR was not significantly different between the two groups (small OR 153.09 ± 22.3 vs. large OR 173 ± 44.6, p = 0.05). CONCLUSIONS: Although total time spent in the room did not differ between the large and small OR, there were significant differences in humidity and ABP rates for particles measuring 2.5 µm and 5.0 µm, suggesting the filtration system encounters less particle burden in larger rooms. Larger studies are required to determine the impact this may have on OR sterility and infection rates.

Patient-Reported Outcomes Following Intra-articular Hyaluronic Acid for Knee Osteoarthritis.

BACKGROUND: Intra-articular hyaluronic acid (IAHA) has been commonly used in the management of knee osteoarthritis (OA). This study sought to assess patient-reported outcomes (PRO) following different formulations of hyaluronic acid injections for patients who have knee OA. METHODS: A retrospective analysis was performed on patients who have knee OA and received IAHA knee injections from October 2018 to May 2022 in sports medicine (SM) and adult reconstructive (AR) clinics. Patients completed PRO measures including the Patient-Reported Outcome Measurement Information System (PROMIS) Mobility, Pain Interference, and Pain Intensity at baseline, 6-week, 6-month, and 12-month follow-up. Univariate and multivariate analyses were used to evaluate changes in PRO measures between baseline and follow-up periods and to evaluate differences between the SM and AR divisions. A total of 995 patients received IAHA for knee OA and completed PRO assessments. RESULTS: There was no difference in the PROMIS measures based on molecular weight at 6 weeks, 6 months, and 12 months. Except for 6-month Mobility scores between the SM and AR patients (-0.52 ± 5.46 versus 2.03 ± 6.95; P = .02), all other PROMIS scores were similar. Mobility scores at 6 months were significantly different based on Kellgren and Lawrence grade (P = .005), but all other PROMIS scores were similar. CONCLUSION: Average change in PROMIS scores were significantly different only for 6-month Mobility scores based on divisions and Kellgren and Lawrence grade but did not achieve minimally clinical important difference at most timepoints. Further studies are needed to investigate whether improvement is observed in specific patient populations.

Trends in Complications and Outcomes in Patients Aged 65 Years and Younger Undergoing Total Hip Arthroplasty: Data From the American Joint Replacement Registry.

This study sought to determine common complications and the rates of readmission and revision in total hip arthroplasty patients younger than 65 years. Using the American Joint Replacement Registry, we conducted a retrospective review of all THAs in patients aged 18 to 65 years from 2012 to 2020. We excluded patients aged older than 65 years, revisions, oncologic etiology, conversion from prior surgery, and nonelective cases. Primary outcomes included cumulative revision rate, 90-day readmission rate, and reason for revision. The Kaplan-Meier method and univariate analysis were used. Five thousand one hundred fifty-three patients were included. The average age was 56.7 years (SD 7.8 years), 51% were female, 85% were White, and 89% had a Charlson Comorbidity Index of 0 (1 = 7%, >2 = 4%). The mean follow-up was 39.57 months. Fifty-three patients (1.0%) underwent revision. Seventy-four patients (1.4%) were readmitted within 90 days. Revision was more common in Black patients (P = 0.023). Survivorship was 99% (95% confidence interval, 98.7 to 99.3) and 99% (95% confidence interval, 98.5 to 99.3) at 5 and 8 years, respectively. Infection (21%), instability (15%), periprosthetic fracture (15%), and aseptic loosening (9%) were the most common indications for revision. Total hip arthroplasty performed in young and presumed active patients had a 99% survivorship at 8 years. A long-term follow-up is needed to evaluate survival trends in this growing population.

Trends in Revenue and Cost for Revision Total Knee Arthroplasty.

BACKGROUND: Over the past decade, reimbursement models and target payments have been modified in an effort to decrease costs of revision total knee arthroplasty (rTKA) while maintaining the quality of care. The goal of this study was to investigate trends in revenue and costs associated with rTKA. METHODS: We retrospectively reviewed all patients who underwent rTKA between 2011 and 2021 at our institution. Patients were stratified into groups based on insurance coverage: Medicare, government-managed or Medicaid (GMM), or commercial insurance. Patient demographics were collected, as well as revenue, costs, and contribution margin (CM) of the inpatient episode. Changes over time as a percentage of 2011 numbers were analyzed. Linear regressions were used to determine trend significance. In the 10-year study period, 1,698 patients were identified with complete financial data. RESULTS: Overall total cost has increased significantly (P < .01). While revenues and CM for Medicare and Commercial patients remained steady between 2011 and 2021, CM for GMM patients decreased significantly (P = .01) to a low of 53.2% of the 2011 values. Since 2018, overall CM and revenues decreased significantly (P = .05, P = .01, respectively). CONCLUSION: While from 2011 to 2018 general revenues and CM were relatively steady, since 2018 they have decreased significantly to their lowest values in over a decade for GMM and commercial patients. This trend is concerning and may potentially lead to decreased access to care. Re-evaluation of reimbursement models for rTKA may be necessary to ensure the financial viability of this procedure and prevent issues with access to care. LEVEL OF EVIDENCE: III.

Patellar Component Design Does Not Impact Clinical Outcomes in Primary Total Knee Arthroplasty.

BACKGROUND: Round or oval implants are used in patellar resurfacing during total knee arthroplasty (TKA). However, whether component geometry affects clinical outcomes is unclear. This study aimed to determine if one implant shape conferred superior outcomes to the other. METHODS: A retrospective review of primary TKA cases performed from 2016 to 2020 was conducted at an urban, tertiary academic center. Four hundred consecutive, primary TKAs were included in these analyses. Cases were included if a surgeon used the round design then oval design for fifty consecutive cases. Baseline demographic data and radiographic measurements were assessed. Surgical data, reasons for revision, and patient-reported outcome measures were analyzed. Independent samples t-test and chi-square tests were used to compare means and proportions. There were no demographic differences between the cohorts. RESULTS: Postoperative patellar tilt was statistically different between the cohorts. Sixteen patients required revision surgery; however, revision rates did not differ between the cohorts. Of the 9 rounds, 1 button was revised for infection. Of the 7 ovals, 1 button was revised for infection and 1 for loosening. Veterans RAND 12 Physical Component Score at 3 months postoperatively was higher for the round cohort, but no differences were observed at 1 year. CONCLUSION: While radiographic patellar tilt was significantly different between the cohorts, there was no clinical correlation in outcomes at 3 months or 1 year postoperatively. Longer-term follow-up studies are needed to evaluate the implications of patellar component design on outcomes and function. Nevertheless, the current study affirms that both designs are clinically equivalent which should be used to guide clinical decision-making. LEVEL III EVIDENCE: Retrospective Cohort.

Implementation of a relapse prevention program among smokers undergoing arthroplasty: lessons learned.

BACKGROUND: Surgery is a potent motivator to help people quit smoking to reduce the risk of complications. Many patients who smoke receive tobacco cessation counseling prior to surgery and are able to quit, but do not receive the same resources after surgery and often resume smoking. METHODS: We present a case study describing the recruitment process, study components, and lessons learned from StayQuit, a comprehensive relapse prevention program designed to prevent relapse after arthroplasty. Lessons learned were examined post hoc to determine challenges related to program implementation, using existing study procedures and information collected. RESULTS: While a comprehensive postoperative relapse prevention program may be beneficial to patients, implementation of StayQuit is unlikely to be feasible under current circumstances. The primary challenges to successful implementation of StayQuit focused on themes of lack of engagement in the preoperative Orthopedic Surgery Quit Smoking Program (OSQSP) and an environment unfavorable to in-person enrollment on the day of surgery. CONCLUSIONS: Postoperative relapse prevention programs may be beneficial for patients who quit smoking prior to elective surgery. To help guide implementation, it is important to consider surgeon behavior, the collaboration of clinical and non-clinical teams, and best practices for study enrollment in surgical settings.

The Impact of Machine Learning on Total Joint Arthroplasty Patient Outcomes: A Systemic Review.

BACKGROUND: Supervised machine learning techniques have been increasingly applied to predict patient outcomes after hip and knee arthroplasty procedures. The purpose of this study was to systematically review the applications of supervised machine learning techniques to predict patient outcomes after primary total hip and knee arthroplasty. METHODS: A comprehensive literature search using the electronic databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews was conducted in July of 2021. The inclusion criteria were studies that utilized supervised machine learning techniques to predict patient outcomes after primary total hip or knee arthroplasty. RESULTS: Search criteria yielded n = 30 relevant studies. Topics of study included patient complications (n = 6), readmissions (n = 1), revision (n = 2), patient-reported outcome measures (n = 4), patient satisfaction (n = 4), inpatient status and length of stay (LOS) (n = 9), opioid usage (n = 3), and patient function (n = 1). Studies involved TKA (n = 12), THA (n = 11), or a combination (n = 7). Less than 35% of predictive outcomes had an area under the receiver operating characteristic curve (AUC) in the excellent or outstanding range. Additionally, only 9 of the studies found improvement over logistic regression, and only 9 studies were externally validated. CONCLUSION: Supervised machine learning algorithms are powerful tools that have been increasingly applied to predict patient outcomes after total hip and knee arthroplasty. However, these algorithms should be evaluated in the context of prognostic accuracy, comparison to traditional statistical techniques for outcome prediction, and application to populations outside the training set. While machine learning algorithms have been received with considerable interest, they should be critically assessed and validated prior to clinical adoption.

The Effect of Surgeon and Hospital Volume on Total Hip Arthroplasty Patient-Reported Outcome Measures: An American Joint Replacement Registry Study.

BACKGROUND: Some studies have shown lower morbidity and mortality rates with increased surgeon and hospital volumes after total hip arthroplasty (THA). This study sought to determine the relationship between surgeon and hospital volumes and patient-reported outcome measures after THA using American Joint Replacement Registry data. METHODS: Using American Joint Replacement Registry data from 2012 to 2020, 4,447 primary, elective THAs with both preoperative and 1-year postoperative Hip Dysfunction and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR) scores were analyzed. This study was powered to detect the minimum clinically important difference (MCID). The main exposure variables were median annual surgeon and hospital volumes. Tertiles were formed based on the median annual number of THAs conducted: low-volume (1 to 42), medium-volume (42 to 96), and high-volume (≥96) surgeons and low-volume (1 to 201), medium-volume (201 to 392), and high-volume (≥392) hospitals. Mean preoperative and 1-year postoperative HOOS-JR scores were compared. RESULTS: Preoperative HOOS-JR scores were significantly higher at high-volume hospitals than low-volume and medium-volume hospitals (49.66 ± 15.19 vs. 47.68 ± 15.09 and 48.34 ± 15.22, P < 0.001), although these differences were less than the MCID. At the 1-year follow-up, no difference was noted with no resultant MCID. Preoperative and 1-year HOOS-JR scores did not markedly vary with surgeon volume. In multivariate regression, low-volume and medium-volume surgeons and hospitals had similar odds of MCID achievement in HOOS-JR scores compared with high-volume surgeons and hospitals, respectively. CONCLUSION: Using the HOOS-JR score as a validated patient-reported outcome measure, higher surgeon or hospital THA volume did not correlate with higher postoperative HOOS-JR scores or greater chances of MCID achievement in HOOS-JR scores compared with medium and lower volume surgeons and hospitals.

Impact of preoperative opioid use on patient-reported outcomes following primary total knee arthroplasty.

PURPOSE: The previous literature suggests that 25-30% of patients who undergo total knee arthroplasty (TKA) are using opioids prior to their surgery. This study aims to investigate the effect of preoperative opioid use on clinical outcomes and patient-reported outcome measures (PROMs) following TKA. METHODS: We retrospectively reviewed 329 patients who underwent primary TKA from 2019 to 2020, answered the preoperative opioid survey, and had available PROMs. Patients were stratified into two groups based on whether they were taking opioids preoperatively or not: 26 patients with preoperative opioid use (8%) and 303 patients without preoperative opioid use (92%) were identified. Demographics, clinical data, and PROMs [Forgotten Joint Score (FJS-12), Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR), and Veterans RAND-12 Physical and Mental components (VR-12 PCS and MCS)] were collected. Demographic differences were assessed with Chi-square and independent sample t-tests. Outcomes were compared using multilinear regression analysis, controlling for demographic differences. RESULTS: Preoperative opioid users had a significantly longer length-of-stay (2.74 vs. 2.10; p = 0.010), surgical time (124.65 vs. 105.69; p < 0.001), and were more likely to be African-American (38.5 vs. 14.2%; p = 0.010) compared to preoperative opioid-naive patients. Postoperative FJS-12 did not statistically differ between the two groups. While preoperative KOOS, JR scores were significantly lower for preoperative opioid users (41.10 vs. 46.63; p = 0.043), they did not significantly differ postoperatively. Preoperative VR-12 PCS did not statistically differ between the groups; however, both 3-month (33.87 vs. 38.41; p = 0.049) and 1-year (36.01 vs. 44.73; p = 0.043) scores were significantly lower for preoperative opioid users. Preoperative VR-12 MCS was significantly lower for preoperative opioid users (46.06 vs. 51.06; p = 0.049), though not statistically different postoperatively. CONCLUSION: At 8%, our study population had a lower percentage of opioid users than previously reported in the literature. Preoperative opioid users had longer operative times and length of stay compared to preoperatively opioid-naive patients. While both cohorts achieved similar clinical benefits following TKA, preoperative opioid users reported lower postoperative scores with respect to VR-12 PCS scores. LEVEL III EVIDENCE: Retrospective Cohort.

Hospital Revenue, Cost, and Contribution Margin in Inpatient Versus Outpatient Primary Total Joint Arthroplasty.

BACKGROUND: Removal of primary total knee arthroplasty (TKA) and primary total hip arthroplasty (THA) from the inpatient-only list has financial implications for both patients and institutions. The aim of this study was to evaluate and compare financial parameters between patients designated for inpatient versus outpatient total joint arthroplasty. METHODS: We reviewed all patients who underwent TKA or THA after these procedures were removed from the inpatient-only list. Patients were statistical significance into cohorts based on inpatient or outpatient status, procedure type, and insurance type. This included 5,284 patients, of which 4,279 were designated inpatient while 1,005 were designated outpatient. Patient demographic, perioperative, and financial data including per patient revenues, total and direct costs, and contribution margins (CMs) were collected. Data were compared using t-tests and Chi-squared tests. RESULTS: Among Medicare patients receiving THA, CM was 89.1% lower for the inpatient cohort when compared to outpatient (P < .001), although there was no statistical significance difference between cohorts for TKA (P = .501). Among patients covered by Medicaid or Government-managed plans, CM was 120.8% higher for inpatients receiving THA (P < .001) when compared to outpatients and 136.3% higher for inpatients receiving TKA (P < .001). CONCLUSION: Our analyses showed that recent costs associated with inpatient stay inconsistently match or outpace additional revenue, causing CM to vary drastically depending on insurance and procedure type. For Medicare patients receiving THA, inpatient surgery is financially disincentivized leaving this vulnerable patient population at a risk of losing access to care. LEVEL III EVIDENCE: Retrospective Cohort Study.

The Cam-Post Dislocation in Posterior-Stabilized Total Knee Arthroplasty A Case Series.

Cam-post dislocations are a unique complication of total knee arthroplasty (TKA) designs that utilize a cam-post mechanism, representing an extreme form of deep flexion instability. They are rare complications and are poorly defined in the existing literature. The purpose of this case study is to present a series of six cam-post dislocation cases to improve understanding of this complication and its mechanism, presentation, and available treatment options. All patients experienced cam-post dislocations after a deep flexion moment that were identified clinically and confirmed radiographically. Affected implants included both primary and revision components and all utilized a cam-post mecha- nism. Three patients underwent revision surgery whereas the remaining three were treated with closed reduction only. Cam-post dislocations are rare complications of posterior- stabilized TKA that should be understood and recognized by adult reconstruction surgeons. Closed reduction may be achieved with hyperflexion and anterior drawer or with hyperextension, but these patients may ultimately require a revision procedure.