168 patients scheduled for total hip arthroplasty through a posterolateral approach were randomized to posterior soft tissue repair through either a tendon-to-bone or tendon-to-tendon method. Patients were assessed over the first 1 year postoperatively for incidents of hip dislocation and suture failure. Cases of suture failure were assessed using No. 26 metal wire placed at an interval of 1.2cm apart during surgery, and then monitored for cases of increase in width between markers of 2.5cm or more during subsequent follow-up. Both dislocation rates and suture failure rates were significantly lower in the tendon-to-bone group compared to the tendon-to-tendon group.