The natural history of a newly developed flexion contracture following primary total knee arthroplasty.

Purpose: We investigated the incidence, natural history, and functional consequences of a newly developed flexion contracture after total knee arthroplasty (TKA).

Methods: Forty patients with full knee extension preoperatively who developed a postoperative flexion contracture were match-paired 1:2 with 80 patients who had full extension. The incidence of a newly developed flexion contracture, ROM, and Knee Society scores (KSS) at six weeks, four months, and one year were analysed.

Results: The incidence of a new flexion contracture at six weeks was 14%, but diminished to 5% and 0.3% at four months and one year, respectively. One year after surgery, there was no difference in the KSS (p = 0.5).

Conclusions: This study showed that the majority of patients who developed a new flexion contracture after TKA have full knee extension one year postoperatively. Moreover, knee extension and KSS at one year are equivalent to those patients who did not developed a flexion contracture.