Effect of repairing capsule and short external rotators on postoperative dislocation rate following pri-mary total hip arthroplasty

Objective To explore the effect of repairing capsule and short external rotators by postero-lateral approach on postoperative dislocation rate following primary total hip arthroplasty. Methods We retrospectively analyzed the 371 cases of primary THA (388 hips) performed through posterolateral approach in our hospital from January 2002 to June 2006. Of them, 116 cases (122 hips) received repair of the posterior capsule and short external rotators which were sutured in figure-of-8 respectively to the greater trechanter of the femur. The postoperative dislocation rate of this group was compared with that of the other 255 eases of routine THA (266 hips) without posterior capsulotendinous repair. There were no significant differences in the mean age, gender, complicated diseases and duration of follow-up between the 2 groups ( P ＞ 0.05).Results In patients with posterior eapsulotendinous repair, only 1 dislocation occurred within 6 months after primary THA (0.8% ); while in patients without posterior capsulotendinous repair, 15 dislocations oc-curred (5.6%). The difference between the 2 groups was statistically significant ( P = 0.027). There was no significant difference in the dislocation rate beyond 6 months between the 2 groups. Conclusion Repair of posterior capsule and short external rotators can effectively prevent early dislocation after primary THA. Key words: Arthroplasty, replacement, hip; Hip disl.ocation; Joint capsule