Does flexion contracture continue to improve up to five years after total knee arthroplasty?

Purpose: To determine whether flexion contracture continues to improve up to 5 years after total knee arthroplasty (TKA).
Methods: Records of 200 women and 123 men (mean age, 72 years) with osteoarthritis and preoperative flexion contracture were reviewed. 155 (48%) involved the left knee and 168 (52%) the right knee. Patients were assessed clinically before TKA and one and 5 years later, by a single researcher using a goniometer to measure flexion contracture, range of movement, maximum flexion, and the Knee Society Score. In all patients the same prosthesis design was used. The surgical technique was standard and involved a medial parapatellar approach with bone resection.
Results: All variables improved significantly from pre-TKA to one-year post-TKA and from one-year post-TKA to 5-year post-TKA; respectively the mean flexion contracture decreased from 11 to 3 to 2 degrees; the mean knee range of movement increased from 90 to 103 to 107 degrees; the mean maximum flexion increased from 101 to 106 to 109 degrees; and the mean Knee Society Scores increased from 39 to 87 to 90.
Conclusion: Functional outcome and flexion contracture may continue to improve up to 5 years after TKA.