A Comparison Between Polyethylene Exchange and Full Revision For Arthrofibrosis Following Total Knee Arthroplasty.

INTRODUCTION: Arthrofibrosis is a debilitating postoperative complication, and a major cause of patient dissatisfaction following total knee arthroplasty (TKA). There is no consensus regarding the optimal treatment for stiffness after TKA. For cases not amenable to manipulation under anesthesia (MUA), one component or full revision are both suitable options. In a value-based healthcare era, maximizing cost-effectiveness with optimized clinical outcomes for patients remains the ultimate goal. As such, we compared (1) Knee Injury and Osteoarthritis Outcome Scores for Joint Replacement (KOOS, JR), (2) ranges of motion (ROM), as well as (3) complication rates, including MUA and lysis of adhesions (LOA), between polyethylene exchange and full component revision for TKA arthrofibrosis.

METHODS: Patients were queried from an institutional database who underwent revision TKA for arthrofibrosis between January 1, 2015, and April 31, 2021. There were 33 patients who underwent full revision and 16 patients who underwent polyethylene exchange. Demographics and baseline characteristics between the cohorts were analyzed. Postoperative outcomes included MUA, LOA, and re-revision rates as well as KOOS, JR, and extension and flexion ROM at a mean follow-up of 3.8 years. Baseline comorbidities, including age, body mass index, alcohol use, tobacco use, and diabetes, were comparable between the full revision and polyethylene exchange revision cohorts (P > 0.05). The one and full component revisions had similar preoperative KOOS, JR (43 versus 42, P = 0.85) and flexion (81 versus 82 degrees, P = 0.80) versus extension (11 versus 11 degrees, P = 0.87) ROM.

RESULTS: The full component revision had higher KOOS, JR (65 versus 55, P = 0.04) and flexion (102 versus 92 degrees, P = 0.02), but similar extension (3 versus 3 degrees, P = 0.80) ROM at final follow-up compared to the polyethylene exchange revision, respectively. MUA (18.2 versus 18.8%, P = 0.96) and LOA (2.0 versus 0.0%, P = 0.32) rates were similar between full component and polyethylene exchange revisions. There was one re-revision (3.0%) for the cohort of patients who initially underwent full revision. There were four full re-revisions (25.0%) and two polyethylene exchange re-revisions (12.5%) performed in the cohort of patients who initially underwent a polyethylene exchange revision.

CONCLUSION: The full component revision for stiffness after TKA showed favorable KOOS, JR, ROM, and outcomes in comparison to the polyethylene exchange revision. While the optimal treatment for stiffness after TKA is without consensus, this study supports the use of the full component revision when applied to the institutional population at hand. It is imperative that homogeneity exists in preoperative definitions, preoperative baseline patient demographics, ROM and function levels, outcome measures, preoperative indications, as the inclusion of clinical data that assesses complete exchange, single exchange, and tibial insert exchange.