EFFECT OF SURGICAL APPROACH ON EARLY DISLOCATION OF TOTAL HIP ARTHROPLASTY

Abstract

Introduction and Objectives: Posterior or posterolateral approaches to the hip joint have classically been associated with higher rates of dislocation. The goal of this study is to investigate the effect of reconstructive procedures of the posterior joint capsule and external rotator muscles in the short term on incidence of luxation and to compare these procedures with anterior or anterolateral approaches in which such procedures were not performed.

Materials and Methods: This is a prospective study of 605 total primary hip arthroplasties based on 2 models that have been widely used in our centre. The cases included 431 biological fixation prostheses coated with hydroxyapatite with 28mm heads and 174 low-friction cemented prostheses with 22.25 mm heads. These surgeries were performed consecutively in our centre, with a minimum follow-up of 6 months. Each patient was assigned to one of two groups based on the individual preference of the surgeon performing the operation: anterior or posterior. Only in the latter group was reconstruction of the capsule and external rotator musculature performed. Cases in which previous surgery had been performed on the hip were not included in this study in order to avoid skewing results, as previous surgery is the factor known to have the greatest impact on dislocation rate.

Results: A procedure involving reconstruction of both the posterior capsule and external rotator musculature significantly reduced the rate of early dislocation in primary total hip arthroplasties done using a posterior approach. Incidence of dislocation in these cases was lower than in cases with anterior approaches where a wider capsulectomy was performed without reconstruction.

Conclusion: The idea that the dislocation rate in total hip arthroplasties is higher with a posterior approach should be reconsidered.