Utility of Synovial White Blood Cell Count and Differential Before Reimplantation Surgery.

BACKGROUND: Determining optimal timing of reimplantation during 2-stage exchange for periprosthetic joint infection (PJI) remains elusive. Joint aspiration for synovial white blood cell (WBC) count and neutrophil percentage (PMN%) before reimplantation is widely performed; yet, the implications are rarely understood. Therefore, this study investigates (1) the diagnostic yield of synovial WBC count and differential analysis and (2) the calculated thresholds for persistent infection. METHODS: Institutional PJI databases identified 129 patients undergoing 2-stage exchange arthroplasty who had joint aspiration before reimplantation between February 2005 and May 2014. Persistent infection was defined as a positive aspirate culture, positive intraoperative cultures, or persistent symptoms of PJI-including subsequent PJI-related surgery. Receiver-operating characteristic curve was used to calculate thresholds maximizing sensitivity and specificity. RESULTS: Thirty-three cases (33 of 129; 25.6%) were classified with persistent PJI. Compared with infection-free patients, these patients had significantly elevated PMN% (62.2% vs 48.9%; P = .03) and WBC count (1804 vs 954 cells/µL; P = .04). The receiver-operating characteristic curve provided thresholds of 62% and 640 cells/µL for synovial PMN% and WBC count, respectively. These thresholds provided sensitivity of 63% and 54.5% and specificity of 62% and 60.0%, respectively. The risk of persistent PJI for patients with PMN% >90% was 46.7% (7 of 15). CONCLUSION: Synovial fluid analysis before reimplantation has unclear utility. Although statistically significant elevations in synovial WBC count and PMN% are observed for patients with persistent PJI, this did not translate into useful thresholds with clinical importance. However, with little other guidance regarding the timing of reimplantation, severely elevated WBC count and differential analysis may be of use.

Length of stay after shoulder arthroplasty-the effect of an orthopedic specialty hospital.

BACKGROUND: One potential avenue for the realization of health care savings is reduction in hospital length of stay (LOS). Initiatives to reduce LOS may also reduce infection and improve patient satisfaction. We compare LOS after shoulder arthroplasty at an orthopedic specialty hospital (OSH) and a tertiary referral center (TRC). METHODS: A single institutional database was used to retrospectively identify all primary shoulder arthroplasties performed between January 1, 2013, and July 1, 2015, at the OSH and TRC. Manually matched cohorts from the OSH and TRC were compared for LOS and readmission rate. RESULTS: There were 136 primary shoulder arthroplasties performed at the OSH matched with 136 at the TRC during the same study period. OSH and TRC patients were similar in age (P = .949), body mass index (P = .967), Charlson Comorbidity Index (P = 1.000), gender (both 52.21% male), procedure (69.12% total shoulder arthroplasty, 7.35% hemiarthroplasty, and 23.53% reverse shoulder arthroplasty), insurance status (P = .714), and discharge destination (P = .287). Despite equivalent patient characteristics, average LOS at the OSH was 1.31 ± 0.48 days compared with 1.85 ± 0.57 days at the TRC (t = 8.41, P < .0001). Of the 136 OSH patients, 3 (2.2%) required transfer to a TRC. Readmission rates for the OSH patients (2/136, 1.5%) and TRC patients (1/136, 0.7%) were similar (z = 0.585, P = .559). CONCLUSION: LOS at the OSH was significantly shorter than at the TRC for a strictly matched cohort of patients. This may be a result of fast-track rehabilitation and strict disposition protocols at the OSH. With rising shoulder arthroplasty demand, utilization of an OSH may be a safe avenue to delivery of more efficient and effective orthopedic care.

Workers' Compensation patients after total joint arthroplasty: do they return to work?

Clinicians identify patients receiving Workers' Compensation (WC) as unlikely to fully benefit from total joint arthroplasty (TJA), with possibly decreased ability to return to work. We completed follow-up for 164 patients undergoing 177 arthroplasties while receiving WC between 2000 and 2009. Inquiry was made regarding work status, nature of work, and return to work time frame. Patients undergoing primary versus revision TJA returned to work 70.2% versus 43.9%, respectively (p=0.002). The mean time frame for return to work following primary TJA was 16.4 weeks. Manual laborers versus sedentary workers returned to work 67.1% versus 84.8%, respectively (p=0.05). As this group is limited by the strenuous nature of their employment, clinicians should be aware that receiving WC may modestly impact return to work following arthroplasty.