Posterolateral Surgical Approach Compared With Modified Lateral Approach

Total hip arthroplasty is one of the most successful orthopaedic procedures for relieving pain and improving quality of life. But dislocation remains the leading early complication after total hip arthroplasty with a reported frequency between 0.4% and 11%. There are several risk factors of dislocation after total hip arthroplasty including patients, implants and surgical approaches. Among lots of risk factors, surgical approach has been debated as one of the important key factor influencing dislocation and abductor function. Direct lateral or posterolateral surgical approach is most commonly used in the total hip arthroplasty. The modified lateral approaches generally are thought to have lower dislocation rates and allow excellent acetabular exposure although limping is increased. The posterolateral approach may allow maintenance of abductor strength but it generally results in a higher dislocation rate. However, there are several reports that the posterolateral approach with capsular repair might be reduced dislocation rate.

We hypothesize the dislocation rate for the posterolateral approach with capsular repair is similar to modified lateral approaches for total hip arthroplasty. A prospective, randomized-controlled study was to examine the null hypothesis that the dislocation rate for the posterior approach with capsular repair was similar to modified lateral approaches for total hip arthroplasty at up to 2 year followup. We attempted to determine whether there was a difference in surgical parameters, component positioning, and clinical results of the modified lateral approach compared with the posterolateral approach.

• Procedure: surgical approach
  Using a gluteus maximus split, the posterolateral approach remains posterior to the gluteus medius and minimus. Exposure of the hip and proximal femur requires division of the posterior hip capsule and the external rotators. The exposure and dislocation are completed with flexion and internal rotation of the femur. After arthroplasty, the external rotators and posterior capsule was routinely repaired using a heavy absorbable suture.
  Other Name: posterolateral approach
• Procedure: modified lateral approach
  The operative technique described modified lateral approach as described by Mulliken et al.

• Active Comparator: posterolateral approach
  The posterolateral approach was described by many authors, but all share a common muscular interval in reference to the gluteus medius tendon. Using a gluteus maximus split, the posterolateral approach remains posterior to the gluteus medius and minimus. Exposure of the hip and proximal femur requires division of the posterior hip capsule and the external rotators. The exposure and dislocation are completed with flexion and internal rotation of the femur. After arthroplasty, the external rotators and posterior capsule was routinely repaired using a heavy absorbable suture.
  Intervention: Procedure: surgical approach
• Active Comparator: modified lateral approach
  The operative technique described modified lateral approach as described by Mulliken et al.
  Intervention: Procedure: modified lateral approach

Inclusion Criteria:

• osteonecrosis
• primary or secondary osteoarthritis of the hips
• femoral neck fracture.

Exclusion Criteria:

• Patients with previous hemi- or total hip arthroplasty
• highly dislocated or severe ankylosed hip
• patients who are considered potentially unreliable or who may not reliably attend study visits