The aim of this study was to determine the outcome of total hip arthroplasty, with regard to dislocation, at our unit. 1727 primary total joint arthroplasties and 305 revision total hip arthroplasties were performed between 1993 and 1996 at our unit. We followed up 1567 of the primary hip arthroplasties and 284 of the revision hip arthroplasties at 8 to 11 years post surgery. Patients were traced by postal questionnaire, telephone interview or examination of case notes of the deceased. The dislocation rates by approach were: 23 out of 555 (4.1%) for the posterior approach, 0 out of 120 (0%) for the Omega approach and 30 out of 892 (3.4%) for the modified Hardinge approach. 58.5% of dislocations after primary total hip arthroplasty were recurrent. The mean number of dislocations per patient was 2.81. 8.1% of revision total hip arthroplasties suffered dislocation. 70% of these became recurrent. The mean number of dislocations per patient was 2.87. The vast majority of dislocations occur within 3 months of surgery. To our knowledge this is the largest multisurgeon audit of dislocation after total hip arthroplasty published in the United Kingdom. The follow-up of 8 to 11 years is longer than most comparable studies.
One hundred Newtons was decided on as the maximum force following measurements in theatre showing a force of approximately 75N were applied to a hamstring ACL graft at the time of fixation in the tibial tunnel. The DVRT’s allowed accurate assessment of the Load/Displacement of each tendon in the construct to be assessed. Repeatability experiments on the DVRT’s were performed. Ten specimens were prepared which were all tested in the different suturing configurations. Each test was repeated three times on each construct.