[Posterior capsule releasing in total knee arthroplasty for patients with rheumatoid arthritis with stiff knees in flexion].

OBJECTIVE

To investigate the correct method of bone resection and posterior capsular soft tissue releasing in total knee arthroplasty (TKA) for the patients with rheumatoid arthritis with stiff knee in flexion.

METHODS

From November 2009 to January 2012,15 patients with rheumatoid arthritis with stiff knee in flexion underwent primary TKA and releasing of the posterior soft tissues. There were 7 males and 8 females,aged 22 to 75 years old (58.7 years old on average). The preoperative range of movement(ROM) was (3.2 ± 1.7)°. According to Knee Society score (KSS) criterion, the preoperative clinical score was 23.3 ± 12.5 and functional score was 35.2 ± 9.8. Based on the correct osteotomy, effective releasing of posterior structures was used for different degrees of flexion contracture during the TKA procedure.

RESULTS

All the patients were followed up, and the average duration was 2.3 years (1.6 to 3 years). At the latest follow-up,the KSS clinical score was 81.7 ± 6.5 and functional score was 82.8 ± 9.3. The flexion and extension ROM of the knee joint was (103.5 ± 13.1). Three knees remained 50 flexion contracture deformity, but the function of the affect knees was good.

CONCLUSION

The effective releasing of the soft tissue of posterior capsule is a major management for correction of the flexion contracture in TKA. The correct releasing of posterior structure can not only achieve fundamental gap of TKA but also effectively avoid bone over-resection.