OBJECTIVES: To compare health economic outcomes after total hip and knee arthroplasty (TJA) when implementing multi-layer watertight closure (MLWC) using knotless barbed suture and 2-octyl cyanoacrylate plus polymer mesh tape compared to conventional closure (CC) using Vicryl sutures and staples.

METHODS: This retrospective observational study identified patients undergoing TJA from a single surgeon at a US hospital (CC group: 2011 to 2013; MLWC group: 2015 to 2018). The study was reviewed and approved by the hospital Institutional Review Board. Outcomes of interest included 90-day SSI and readmission rates, length of stay (LOS) and discharge status. Following bivariate analyses, adjusted interrupted time series analyses were conducted to account for decreasing trends in LOS and shift in discharge status over the study period.

RESULTS: In total, 2167 TJA cases were included in this study (N_CC = 906, N_MLWC = 1261). Bivariate analysis showed that despite no statistically significant differences in 90-day SSI rates, patients in the MLWC cohort had 60% lower 90-day readmission rates (1.5% vs 3.8%, p<0.05), 44% lower LOS (1.4 days vs. 2.5 days, p<0.05) and 40% lower discharge rates to a skilled care facility (8.5% patients vs 14.1%, p<0.05) compared to patients in the CC cohort. Interrupted time series analyses showed a sharp decline in LOS (0.9 days) and discharge status to a skilled care facility (5.6% incidence) immediately after implementation of the MLWC approach. A levelling of the data with no further changes in LOS or discharge status were observed for the remainder of the study period.

CONCLUSIONS: MLWC compared to a CC approach in a TJA cohort was associated with at least 40% reduction in 90-day readmission rates, LOS and discharge to a skilled facility. Interrupted time series analyses confirmed the impact of introducing a MLWC approach despite shifting trends in LOS and discharge status.