Abstract
Purpose
Hip arthroplasty is a good treatment option for displaced femoral neck fracture in elderly patients. However, neuromuscular disease such as cerebral infarction or hemorrhage can be a concerning problem for THA since dislocation after operation can frequently occur. The purpose of this prospective study was to evaluate the functional results of modified minimally invasive (MI) two-incision total hip arthroplasty (THA) with the use of large-diameter (>38mm) metal-on-metal articulation in patients with muscle weakness.
Patients and Methods
19 consecutive patients (19 hips) with displaced femoral neck fracture with muscle weakness were enrolled. There were 11 patients with cerebral infarction, 4 patients with cerebral hemorrhage and 4 patients with Parkinson's disease. In the lateral position, an anterolateral approach between the gluteus medius and tensor fascia lata and a posterior approach between the piriformis and gluteus medius were used.
Surgical morbidity, functional recovery, radiological implantation properties, range of motion (ROM) and complications were assessed.
Results
The mean operation time was 73.5 minutes and the average perioperative blood loss was 725.9cc. The mean head diameter used was 44 mm (38–50). The mean lateral opening angle of the acetabular component was 38.4°, the mean anteversion of the acetabular component was 16.4°, and the mean stem position was 0.3° valgus. The average postoperative ambulation time was 2.4 days. The mean Harris hip score was 81.0 at final follow-up, and the mean WOMAC score was 42.9. At final follow-up, there was no case of dislocation. There was no hypersensitivity, no osteolysis, and no revision.
Conclusions
Our study suggests that the functional results of modified MI two-incision THA with the use of large-diameter metal on metal articulation in patients with muscle weakness can produce satisfactory early functional recovery and can reduce the dislocation rate.
