Relationship of the Posterior Condylar Line and the Transepicondylar Axis: A CT-Based Evaluation.

Posterior condylar referencing, a common method for determining femoral axial orientation during total knee arthroplasty (TKA), relies upon an assumed consistent relationship between the posterior condylar line (PCL) and the transepicondylar axis (TEA) of 3 degrees rotation. A total of 3,010 computed tomography (CT) scans and three-dimension (3D)-reconstructions for presurgical creation of patient-matched TKA instrumentation were analyzed. Demographic data and five anthropometric measurements (hip-knee angle [HKA], distal femoral angle [DFA], proximal tibial angle [PTA], tibial slope [TS], and PCL-TEA relationship) were recorded for each scan. A logistic regression model was fit to assess interaction between the PCL-TEA relationship and demographic and radiological variables. The mean (standard deviation [SD]) PCL-TEA was +2.9 degrees (0.8 degree). The range varied between +0.5 and +16.5 degrees. In 2,758 knees (91.6%), the PCL-TEA was within 3 ± 1 degrees, whereas 252 knees (8.4%) fell outside this range. There were no significant demographic or anthropometric differences between those knees with PCL-TEA relationship between 3 ± 1 degrees and those falling outside that range. The posterior condyles of diseased knees undergoing TKA can be reliably used to indirectly reference the TEA of the distal femur with an error of only 1 degree in 92% of patients.

Preoperative Opioid Use Negatively Affects Patient-reported Outcomes After Primary Total Hip Arthroplasty.

BACKGROUND: Opioid use is a public health crisis in the United States and an area of increased focus in orthopaedic surgery. The aim of this study is to investigate whether preoperative opioid use had any effect on patient-reported outcome measures (PROMs) before and after total hip arthroplasty (THA). METHODS: A total of 389 patients with THA with both preoperative and postoperative PROMs were reviewed: (1) 76 patients with preoperative opioid use (24%) and (2) 237 patients without preoperative opioid use (76%). Patient demographics and clinical information including opioid use, length of stay, and implant information. RESULTS: Preoperative opioid users were more likely to stay in the hospital longer (P = 0.004) and be discharged to a rehabilitation facility (P = 0.038). Postoperatively, the Physical Function Short Form 10a (P = 0.021) and Patient-Reported Outcomes Measurement Information System Global-10 (P < 0.001 physical, P = 0.001, mental) were significantly lower in the preoperative opioid users. Within groups, both nonusers and preoperative opioid users saw improvements after THA in Hip Disability and Osteoarthritis Outcome Score-Physical Function Short Form (P < 0.001), Short Form 10a (P < 0.001), and Patient-Reported Outcomes Measurement Information System Global-10 (P < 0.001, physical and P = 0.008, mental). DISCUSSION: Although all patients reported improvements after THA regardless of preoperative opioid use, preoperative opioid users undergoing THA had significantly lower patient-reported outcome scores, longer hospital stays, and a more likely discharge to rehabilitation.

Early diagnosis of septic arthritis in immunocompromised patients.

OBJECTIVES: Septic arthritis results in rapid joint destruction if not properly diagnosed and treated. A work up for septic arthritis includes a peripheral white blood cell count, inflammatory markers, and a joint aspiration. In the general population, the interpretation of these labs has been well-defined by prior studies. To this point, no study has determined how immunosuppressive states affect this work up. METHODS: Patients with immunosuppressive conditions who received a joint aspiration for a painful joint were retrospectively identified. Laboratory results from their work up were gathered and analyzed. RESULTS: 216 patients were included in the study, 21 of whom were diagnosed with septic arthritis. The average aspiration WBC count was 74,190 with 88% PMNs. 81% had a positive gram stain. DISCUSSION: Laboratory values for immunosuppressed patients with septic arthritis were similar to those associated with septic arthritis in historical general population controls.

Differences in Post-Operative Outcome Between Conversion and Primary Total Hip Arthroplasty.

BACKGROUND: The demand for conversion of prior hip surgery to total hip arthroplasty (conversion THA) is likely to increase as a function of increasing US hip fracture burden in addition to its application in managing other conditions. Thus, outcome analysis is warranted to better inform value-based reimbursement schemes in the era of bundled payments. METHODS: Via Current Procedural Terminology codes, the National Surgical Quality Improvement Project data files were queried for all patients who underwent primary THA and conversion of previous hip surgery to THA from 2005 to 2014. To better understand the isolated effect of procedure type on adverse outcomes, primary and conversion cohorts were then propensity-score matched via logistic regression modeling. Comparisons of the study's primary outcomes were drawn between matched cohorts. Statistical significance was defined by a P-value less than or equal to .05. RESULTS: Relative to the primary THA group, the conversion THA group had statistically greater rates of Center Medicare and Medicaid Services (CMS) complications (7.5% vs 4.5%), non-home bound discharge (19.6% vs 14.7%), and longer length of hospital stay. Conversion THA was associated with increased likelihood of CMS complications (odds ratio 1.68, confidence interval 1.39-2.02) and non-home bound discharge (odds ratio 1.41, confidence interval 1.25-1.58). No statistically significant differences in mortality and readmission were detected. CONCLUSION: The elevated risk for CMS-reported complications, increased length of hospital stay, and non-home bound discharge seen in our study of conversion THA indicates that it is dissimilar to elective primary THA and likely warrants consideration for modified treatment within the Comprehensive Care for Joint Replacement structure in a manner similar to THA for fracture.

The Lawrence D. Dorr Surgical Techniques & Technologies Award: Differences in Postoperative Outcomes Between Total Hip Arthroplasty for Fracture vs Osteoarthritis.

BACKGROUND: Hip fracture is an increasingly common expanded indication for total hip arthroplasty (THA) and warrants outcome analysis so as to best inform risk assessment models, public reporting of outcome, and value-based reimbursement schemes. METHODS: The National Surgical Quality Improvement Program data file from 2011 to 2014 was used to identify all patients undergoing THA via current procedural terminology code 27130. Propensity score matching in a 1:5 fashion was used to compare 2 cohorts: THA for osteoarthritis and THA for fracture. Primary outcomes included Centers for Medicare and Medicaid Services (CMS) reportable complications, unplanned readmission, postsurgical length of stay, and discharge destination. χ2 tests for categorical variables and Student t test for continuous variables were used to compare the 2 cohorts and adjusted linear regression analysis used to determine the association between hip fracture and THA outcomes of interest. RESULTS: A total of 58,302 patients underwent elective THA for osteoarthritis and 1580 patients underwent THA for hip fracture. Rates of CMS-reported complications (4.0% vs 10.7%; P < .001), non-homebound discharge (39.8% vs 64.7%; P < .001), readmission (4.7% vs 8.0%; P < .001), and mean days of postsurgical hospital stay (3.2 vs 4.4; P < .001) were greater in the hip fracture cohort. THA for hip fracture was significantly associated with increased risk of CMS-reportable complications (odds ratio [OR], 2.67; 95% confidence interval [CI], 2.17-3.28), non-homebound discharge (OR, 1.73; 95% CI, 1.39-2.15), and readmission (OR, 2.78; 95% CI, 2.46-3.12). CONCLUSION: Our findings support recent advocacy for the exclusion of THA for fracture from THA bundled pricing methodology and public reporting of outcomes.

The Impact of Metabolic Syndrome on 30-Day Complications Following Total Joint Arthroplasty.

BACKGROUND: The arthroplasty population increasingly presents with comorbid conditions linked to elevated risk of postsurgical complications. Current quality improvement initiatives require providers to more accurately assess and manage risk presurgically. In this investigation, we assess the effect of metabolic syndrome (MetS), as well as the effect of body mass index (BMI) within MetS, on the risk of complication following hip and knee arthroplasty. METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program database for total hip or knee arthroplasty cases. Thirty-day rates of Centers for Medicare and Medicaid Services (CMS)-reportable complications, wound complications, and readmissions were compared between patients with and without a diagnosis of MetS using multivariate logistic regression. Arthroplasty cases with a diagnosis of MetS were further stratified according to World Health Organization BMI class, and the role of BMI within the context of MetS was assessed. RESULTS: Of the 107,117 included patients, 11,030 (10.3%) had MetS. MetS was significantly associated with CMS complications (odds ratio [OR] = 1.415; 95% confidence interval [CI], 1.306-1.533; P < .001), wound complications (OR = 1.749; 95% CI, 1.482-2.064; P < .001), and readmission (OR = 1.451; 95% CI, 1.314-1.602; P < .001). When MetS was assessed by individual BMI class, the MetS + BMI >40 group was associated with significantly higher risk of CMS complications, wound complications, and readmission compared to the lower MetS BMI groups. CONCLUSION: MetS is an independent risk factor for CMS-reportable complications, wound complications, and readmission following total joint arthroplasty. The risk attributable to MetS exists irrespective of obesity class and increases as BMI increases.