Faculty Bibliography

Given the steady increase in the number of primary and revision total knee arthroplasties (TKAs) performed in the United States, we wanted to determine if an evidence-based TKA perioperative surgical home could close the perioperative morbidity gap between primary and revision TKAs. We conducted a prospective cross-sectional cohort study comparing outcomes of patients who had primary TKA (n = 235) with outcomes of patients who had revision TKA (n = 50). We measured several perioperative outcomes: length of stay, discharge disposition, 30-day readmission rate, and 30-day reoperation rate. Mean length of stay was 2.55 days for primary TKA and 2.92 days for revision TKA (P = .061). Eighty (34%) of the 235 primary TKA patients and 21 (41%) of the 51 revision TKA patients were discharged to a subacute nursing facility (P = .123). One primary TKA patient (0.4%) and 2 revision TKA patients (4%) were readmitted within 30 days after surgery (P = .081). None of the primary TKAs and 2 (4%) of the revision TKAs underwent reoperation (P = .993). There was no difference in perioperative outcomes between the primary and revision TKA groups in our Total Joint Replacement Perioperative Surgical Home (TJR-PSH) cohort. Advances in multidisciplinary co-management of TKA patients are highlighted in the TJR-PSH. The similarity in primary and revision TKA outcomes has significant implications regarding costs and potential increased patient satisfaction.

OBJECTIVE: To test whether use of a personalized report card, Nursing Home Compare Plus (NHCPlus), embedded in a reengineered discharge process, can lead to better outcomes than the usual discharge process from hospitals to nursing homes. DATA SOURCES/SETTING: Primary data collected in the Departments of Medicine and Surgery at a University Medical Center between March 2014 and August 2015. STUDY DESIGN: A randomized controlled trial in which patients in the intervention group were given NHCPlus. Participants included 225 patients or their family members/surrogates. DATA COLLECTION: Key strokes of NHCPlus users were recorded to obtain information about usage. Users were surveyed about usability and satisfaction with NHCPlus. All participants were surveyed at discharge from the hospital. Survey data were merged with medical records. PRINCIPAL FINDINGS: About 85 percent of users indicated satisfaction with NHCPlus. Compared to controls, intervention patients were more satisfied with the choice process (by 40 percent of the standard deviation p < .01), more likely to go to higher ranked five-star nursing homes (OR = 1.8, p < .05), traveled to further nursing homes (IRR = 1.27, p < .10), and had shorter hospital stays (IRR = 0.84, p < .05). CONCLUSIONS: Personalizing report cards and reengineering the discharge process may improve quality and may lower costs compared to the usual discharge process.

Introduction/objectives: Individuals co-infected with both HCV) and HIV represent a unique and growing population of patients undergoing orthopaedic surgical procedures. Data regarding complications for HCV monoinfection or HIV monoinfection is robust, but there exists a paucity of data regarding coinfected individuals. Methods: State-wide database was used to identify patients undergoing THA between 2010-2014. Patients were stratified into 4 groups based upon HCV/HIV status: healthy controls without disease, HCV monoinfection, HIV monoinfection, and co-infection. Differences regarding hospital LOS (days), total charges ($USD), discharge disposition, in-hospital complications, in-hospital mortality, and hospital readmission were calculated. Results: 80,722 patients underwent THA between 2010-2014. 98.55% had neither HCV nor HIV, 0.66% had HCV, 0.66% HIV and 0.13% were coinfected with both HCV and HIV. Co-infected patients were more likely to be younger, male, insured by Medicaid, history of AVN and be homeless. Additionally, co-infected patients had the highest rates of alcohol abuse, drug abuse, tobacco, and high rates of psychiatric disorders, including depression. HCV and HIV co-infection was an independent risk factor for increased LOS (p<0.001), total hospital charges in the 90th percentile (p<0.001), having 2 or more in-hospital complications (p<0.001), and 90-day readmission rates (p<0.001). Conclusions: As the prevalence of HCV and HIV co-infectivity continues to increase, surgeons will encounter a greater number of these patients. Awareness of the demographic and socioeconomic factors leading to increased complications after THA will allow physicians to consider interventions to improve patient health status in order to optimize outcomes and reduce costs

Introduction/objectives: Spinal deformity has a known deleterious effect upon the outcomes of THA and acetabular component positioning. This study sought to evaluate the relationship between severity of spinal deformity parameters and acetabular cup position, rate of dislocation, and rate of revision among patients with THAs and concomitant spinal deformity. Methods: A prospectively database of patients with spinal deformity was reviewed and patients with THA were identified. The full standing stereoradiographic images (EOS) were reviewed. Spinal deformity parameters and acetabular cup anteversion and inclination were measured. A chart review was performed to determine dislocation and revision arthroplasty events. Statistical analysis was performed to determine correlation of deformity with acetabular cup position. Subgroup analysis was performed for spinal fusion, dislocation events, and revision THA. Results: 142 patients were identified with THA and spinal deformity, with 152 hips. The rate of dislocation was 5.7%, with a revision rate of 3.6% for instability. Only 42.1% met the radiographic "safe zone" criteria. 7 (77.8%) of the 9 dislocations occurred in patients with acetabular cups outside the safe zone (p = 0.304). Patients with dislocations had significantly higher inclination than those patients who did not dislocate (p = 0.016), but had no difference in anteversion (p = 0.646). Conclusions: In this cohort, patients with THA and concomitant spinal deformity have a high dislocation rate and a high percentage of acetabular cups which lie outside the safe zone in the standing position. Known spinal deformity parameters and the presence of spinal fusion do not correlate strongly with cup position or dislocation rates

Introduction/objectives: Adult spinal deformity correction results in changes in acetabular anteversion. Spinopelvic fusion reduces the protective motion of the pelvis between sitting and standing to prevent THA dislocation. Our hypothesis is that spinal deformity correction may result in dislocation of previously stable THA due to changes in acetabular orientation and fixation to the pelvis. Methods: Patients with previously implanted THA were identified from a prospective database of spinal realignment patients if they had a THA in situ prior to spinal surgery. Only patients with at least 6 months postoperative follow-up and visible THA prostheses were included. All postoperative imaging was reviewed. A chart review was performed to determine the indication for revision THA. Acetabular orientation and global/regional spinopelvic parameter were measured pre-and post-SSD correction. Results: 42 patients met criteria. 27 of these patients underwent a 3-column osteotomy. Four patients (7.2% of patients-5.7% hips) required revision THA after spinal realignment procedure: all revisions were for recurrent dislocations. All had stable THAs prior to spinal realignment. All acetabular components were within Lewinnek's 'safe zone' after ASD correction. There was no difference between the revised and non-revised group in mean anteversion or inclination. All hips requiring revision were fused to the pelvis as part of their SSD correction. Conclusions: Dislocation of a previously stable THA is a potential complication after ASD correction. Instability may be a result of a combination of change in alignment of the acetabular prosthesis, as well as reduced spinopelvic motion from spinopelvic fusion

Introduction/objectives: Lumbar fusion is known to reduce the variation in pelvic tilt between standing and sitting by reducing flexibility of the lumbar spine. Flexibility of the lumbo-pelvic segment theoretically improves stability of a hip replacement during sitting by increasing anterior clearance and acetabular anteversion, thus preventing prosthetic impingement. The effect of lumbar fusion on stability of THA has not been previously investigated. Methods: Medicare database was searched from 2005 to 2012 for patients who underwent THA and spinal fusion. PearlDiver software was used to query the database by ICD-9 procedural code for primary THA and lumbar spinal fusion. The lumbar fusion and THA patients were then divided into three groups-1-2 levels fused, 3-7 levels, and 8 + levels. THA dislocation rates were searched within each group. Patients undergoing THA but no spinal fusion were used as the control group. Statistical significant difference between groups was tested with chi-squared test, and significance at p<0.05. Results: 2912 patients were identified to have THA after lumbar spinal fusion (2420 1-2 level, 476 3-7 level) and 2-year follow-up. The control group of THA patients with no history of spinal fusion consisted of 839,004 patients. The dislocation rate in the control group was 1.55%. Higher dislocation rates were found in patients with spinal fusion of 1-2 levels (2.73%, p<0.0001), 3-7 levels (4.62%, p<0.0001). Patients with 3-7 levels fused had higher dislocation rates than patients with 1-2 levels fused (p<0.0001). Conclusions: Patients with a previous history of lumbar spinal fusion have significantly higher rates of dislocation of their THA than patients without lumbar spinal fusions, and longer fusion segments also had higher dislocation rates

Introduction/objectives: Peri-prosthetic joint infections (PJI) are a continued concern in arthroplasty surgery. The rate of PJIs for total hip arthroplasty (THA) procedures varies from 0.3% to 2.9%. Irrigation & debridement (I&D) with a head and liner exchange is often performed to treat this complication. Early management of PJI is cited to offer a higher success rate. The purpose of this study is to evaluate the efficacy and timing of I&D for PJI in THA. Methods: We reviewed the records of 39 patients that underwent a THA between January 5th, 2009 and October 30th, 2014 who subsequently had an I&D with a head and liner exchange to treat a PJI. Date of THA and date of I&D with ahead and liner exchange were recorded. Success was measured by the need for any additional procedure due to persistent infection. Results: The average time between THA and I&D with a head and liner exchange was 48 days. Successful I&Ds took place an average of 46.8 days after the initial THA while unsuccessful I&Ds were performed 51.6 days after the initial THA. The difference, however, was not statistically significant. Conclusions: Our results demonstrate the average time to I&D with a head and liner exchange was shorter for those who had a successful outcome but the difference between the two groups was not significant. A short time interval between arthroplasty and I&D is recommended by most authors but our results did not support this view

Introduction/objectives: Computer/robotic navigation has been shown to improve the precision of acetabular component position in THA. The purpose of our study was to utilize robotic-arm assisted computer navigation to assess the reliability of pelvic position in total hip arthroplasty, which can directly impact anteversion and inclination. Methods: 100 hips underwent a CT-guided robotic THA via a minimally invasive posterior approach in the lateral position. The surgeon placed the robotic arm parallel to the longitudinal axis of the patient and the horizontal surface of the table, representing 0 degrees anteversion and inclination. The software generated values of this perceived zero-zero position based on the registration of the patient's preoperative CT. To ensure the accuracy of measurements, cup anteversion and inclination at time of impaction were recorded and compared to 3 month postop X-rays. Results: 22% of anteversion values were altered by >10 degrees and 41% of anteversion values were altered by >5 degrees. Range of anteversion was-20 to 20 degrees. 2% of inclination values were altered by >10 degrees. 18% of inclination values were altered by >5 degrees. Anteversion differences were correlated with patient BMI (p = 0.02). There was no difference in robotic planned anteversion and inclination compared to postoperative X-rays (21.8 vs 21.9 degrees anteversion; 40.6 vs 40.5 degrees inclination). Conclusions: Pelvic positioning devices offer up to 20 degrees of variability in acetabular cup orientation. Compounding this with the fact that human error is prone to 10 degrees of anteversion inaccuracy, it is essential to ensure accurate patient position or use some form of computer/robotic navigation to place acetabular components within the well defined safe zones