Faculty Bibliography

BACKGROUND: Revision total hip arthroplasty (RHA) has been associated with greater morbidity and length of stay (LOS) compared to primary total hip arthroplasty. Despite this, few validated metrics exist for risk stratification in RHA cohorts. The Charlson Comorbidity Index (CCI) has been associated with complications in total hip arthroplasty, but its utility in revision surgery remains unexplored. The purpose of this study was to examine the relationship between preoperative CCI and a variety of outcome metrics following RHA. METHODS: The National Surgical Quality Improvement Program database was used to identify all patients undergoing aseptic RHA between 2006 and 2013. A variety of demographics and perioperative variables were collected. Modified CCI scores were computed for each patient based on a validated formula incorporating comorbidities found in the National Surgical Quality Improvement Program database. Outcome variables of interest included mortality, major postoperative complications, minor adverse events, incidence of transfusion, and prolonged LOS. Perioperative factors were tested for association with these outcomes using bivariate analysis and significant variables were then incorporated into a logistic regression model to explore the relationship between preoperative CCI scores and postoperative events. RESULTS: In a multivariable regression model controlling for the significant perioperative variables, operative time, and American Society of Anesthesiologists classification, higher CCI scores were significantly associated with mortality (odds ratio [OR] 1.89, 95% confidence interval [CI] 1.64-2.18, P < .001), major complications (OR 1.12, 95% CI 1.05-1.20, P = .001), minor complications (OR 1.53, 95% CI 1.39-1.69, P < .001), transfusions (OR 1.14, 95% CI 1.09-1.20, P < .001), and prolonged LOS (OR 1.32, 95% CI 1.26-1.39, P < .001). CONCLUSION: Higher preoperative CCI scores were independent risk factors for numerous complications. This highlights the potential utility of the CCI in risk stratification for RHA populations.

Paget's disease of the bone is a chronic osteopathy that leads to structural weakness, hypervascularity, and bone deformities. Rapid bone turnover in patients with Paget's disease may affect outcomes following total hip arthroplasty (THA). Most literature on THA in the setting of Paget's disease is limited to isolated case reports or case series documenting a single institution experience. By completing a comprehensive analysis of the available cases, this study aims to investigate the outcomes and complications of THA in patients with Paget's disease.

BACKGROUND: The Bundled Payment for Care Improvement (BPCI) Initiative is a Centers for Medicare and Medicaid Services program designed to promote coordinated and efficient care. This study seeks to report costs of readmissions within a 90-day episode of care for BPCI Initiative patients receiving total knee arthroplasty (TKA) or total hip arthroplasty (THA). METHODS: From January 2013 through December 2013, 1 urban, tertiary, academic orthopedic hospital admitted 664 patients undergoing either primary TKA or THA through the BPCI Initiative. All patients readmitted to our hospital or an outside hospital within 90-days from the index episode were identified. The diagnosis and cost for each readmission were analyzed. RESULTS: Eighty readmissions in 69 of 664 patients (10%) were identified within 90-days. There were 53 readmissions (45 patients) after THA and 27 readmissions (24 patients) after TKA. Surgical complications accounted for 54% of THA readmissions and 44% of TKA readmissions. These complications had an average cost of $36,038 (range, $6375-$60,137) for THA and $38,953 (range, $4790-$104,794) for TKA. Eliminating the TKA outlier of greater than $100,000 yields an average cost of $27,979. Medical complications of THA and TKA had an average cost of $22,775 (range, $5678-$82,940) for THA and $24,183 (range, $3306-$186,069) for TKA. Eliminating the TKA outlier of greater than $100,000 yields an average cost of $11,682. CONCLUSION: Hospital readmissions after THA and TKA are common and costly. Identifying the causes for readmission and assessing the cost will guide quality improvement efforts.

A 35-year-old female presented to orthopaedic clinic with a chief complaint of chronic left hip pain, beginning 17 years prior when she had sustained a gunshot wound to her left buttock. Imaging demonstrated significant left hip arthritis with a retained projectile in the femoral head. Lead levels were also found to be significantly elevated. The patient underwent successful left total hip arthroplasty, with subsequent postoperative pain relief and consistent decrease in serum lead level. This report presents a rare case that emphasizes lead intoxication as a potentially dangerous complication of gunshot wounds and retained projectiles in the orthopaedic patient. Recognition of lead intoxication as a potential complication of retained gunshot projectiles allows for efficient diagnosis and treatment, which may prevent associated future morbidity.

BACKGROUND: Regional analgesia is more effective than conventional analgesia for controlling pain and may facilitate rehabilitation after large joint replacement in the short term. It remains unclear if regional anaesthesia improves functional outcomes after joint replacement beyond three months after surgery. OBJECTIVES: To assess the effects of regional anaesthesia and analgesia on long-term functional outcomes 3, 6 and 12 months after elective major joint (knee, shoulder and hip) replacement surgery. SEARCH METHODS: We performed an electronic search of several databases (CENTRAL, MEDLINE, EMBASE, CINAHL), and handsearched reference lists and conference abstracts. We updated our search in June 2015. SELECTION CRITERIA: We included randomized controlled trials (RCTs) comparing regional analgesia versus conventional analgesia in patients undergoing total shoulder, hip or knee replacement. We included studies that reported a functional outcome with a follow-up of at least three months after surgery. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We contacted study authors for additional information. MAIN RESULTS: We included six studies with 350 participants followed for at least three months. All of these studies enrolled participants undergoing total knee replacement. Studies were at least partially blinded. Three studies had a high risk of performance bias and one a high risk of attrition bias, but the risk of bias was otherwise unclear or low.Only one study assessed joint function using a global score. Due to heterogeneity in outcome and reporting, we could only pool three out of six RCTs, with range of motion assessed at three months after surgery used as a surrogate for joint function. All studies had a high risk of detection bias. Using the random-effects model, there was no statistically significant difference between the experimental and control groups (mean difference 3.99 degrees, 95% confidence interval (CI) - 2.23 to 10.21; P value = 0.21, 3 studies, 140 participants, very low quality evidence).We did not perform further analyses because immediate adverse effects were not part of the explicit outcomes of any of these typically small studies, and long-term adverse events after regional anaesthesia are rare.None of the included studies elicited or reported long-term adverse effects like persistent nerve damage. AUTHORS' CONCLUSIONS: More high-quality studies are needed to establish the effects of regional analgesia on function after major joint replacement, as well as on the risk of adverse events (falls).

We explored the average cost of 94,197 total knee and 78,541 total hip arthroplasties (TKA and THA) using the New York State Hospital Inpatient Cost Transparency database to evaluate the effect of beneficiary health status on hospital reported cost for the two operations. Using the 3M APR-DRG severity of illness index as a measure of patient's health status, we found a significant increase in cost for both TKA and THA for patients with higher severity of illness index. This study confirms the greater cost and variability of TKA and THA for patients with increased severity of illness and illustrates the inherent unpredictability in cost forecasting and budgeting for these same patients.

There is currently wide variation in the use and cost of post acute care following total joint arthroplasty. Additionally the optimum setting to which patients should be discharged after surgery is controversial. Discharge patterns following joint replacement vary widely between physicians at our institution, however, only weak correlations were found between the cost of discharge and length of stay or readmission rates. The inter-physician variance in discharge cost did not correlate to a difference in quality, as measured by length of stay and readmission rates, but does imply there is significant opportunity to modify physician discharge practices without impacting patient outcomes and the quality of care.

The significantly higher incidence of anterior cruciate ligament (ACL) injuries in collegiate women compared with men may result from relative ligament laxity. Differences in estrogen and relaxin activity, similar to that seen in pregnancy, may account for this. We quantified estrogen receptors by flow cytometry and relaxin receptors by radioligand binding assay in human ACL cells and compared the presence of these receptors in males and females. ACL stumps were harvested from seven males and eight females with acute ACL injuries. The tissue was placed in M199 cell culture medium. Outgrowth cultures were obtained, and passage 2 cells were used for all studies. Estrogen receptor determination was performed using flow cytometry. Relaxin binding was performed in ACL cells derived from five female and male patients using I(125)-labeled relaxin. Estrogen receptors were identified by flow cytometry in 4 to 10% of ACL cells. Mean fluorescence of cells expressing estrogen receptors was approximately twice that of controls, with no significant differences between males and females. Relaxin studies showed low-level binding of I(125)-relaxin-labeled ACL cells. Relaxin binding was present in four out of five female ACL cells versus one out of five male ACL cells