Total Knee Arthroplasty in Patients with Greater than 20 Degrees Flexion Contracture

Abstract
Fixed flexion contracture can present a technical challenge in total knee arthroplasty. Various techniques of addressing these deformities have been described including additional bony resection, ligamentous releases, and the use of increasing constraint. We retrospectively reviewed the clinical outcomes of 40 patients (52 knees) with fixed flexion contracture greater than or equal to 20 degrees treated with revision TKA and a stepwise algorithmic approach to treating the contracture. A cruciate-retaining device was used in 31 knees, a posterior stabilized design was used in 14, a posterior stabilized constrained device was used in five knees, and a rotating hinged design in was used in two knees. Full correction was achieved intraoperatively. Ninety-four percent of knees had less than 10 degrees residual contracture at an average followup of 37 months. We revised one case of postoperative instability in the posterior stabilized group and we had one infection in the cruciate-retaining group. No other revisions were performed. The stepwise algorithmic approach to treating fixed flexion deformity presented in this study in primary total knee arthroplasty is safe and effective.