Polyethylene exchange versus full component revision for arthrofibrosis following total knee arthroplasty: A retrospective cohort analysis

Introduction: Arthrofibrosis occurs in up to 10% of patients who undergo total knee arthroplasty (TKA). For cases that are not amenable to manipulation under anesthesia (MUA), there is little consensus on how many components should be revised. We compared outcomes of polyethylene exchanges, when doing lysis of adhesions (LOA) versus full component revision. Specifically, we assessed: (1) re-operation rates at one and two years; (2) rates of surgical complications at one year; and (3) associated risk factors for requiring a LOA. Methods: A database queried all patients who underwent revision TKA for arthrofibrosis. A total of 2410 patients were identified, 1120 (46.5%) of which underwent all-component knee revision, while the remaining 1290 (53.5%) underwent polyethylene spacer revision. Multivariate logistic regressions assessed re-operation rates and risk factors for requiring LOA. Results: The incidence and odds of re-operation within one year following polyethylene exchange was not significantly different than full component revision (10.9 versus 12.9%, odds ratio (OR) 0.83, 95% confidence interval (CI) [0.64-1.06], p = 0.145). However, the adjusted models for re-operation within one- and two-years following LOA in the form of polyethylene exchange revision was significantly higher than the full component revision cohort (OR 1.52 CI [1.07-2.17], p = 0.022 and OR 1.44 CI [1.06-1.97] p = 0.022). Risk factors associated with the need for lysis of adhesions included age less than 60 years, depression, fibromyalgia, and anxiety. Conclusions: Full component revision TKA for arthrofibrosis was associated with lower two-year re-operation rate than polyethylene exchange. Risk factors for LOA include younger age and fibromyalgia.