Short Term Results of Total Hip Arthroplasty using the Impact Modular Hip System

Between 1993 and 1994, twenty-six hip arthroplasties were performed on 25 patients using the Impact Modular Hip System. This system maintains the entire femoral neck by allowing the resection to be made at the head/neck junction. By saving the femoral neck, minimal bone is removed. It also permits the entire implant to rest within the neck region where it can obtain unsurpassed rotational stability and transfer physiological load along the trabecular path. Preoperative diagnosis was osteoarthritis of the hip in 19 hips, avascular necrosis of the femoral head in 2, and miscellaneous in 5. The JOA hip score averaged 56.5 points before surgery. The average age of the patients at the time of surgery was 62.5 years, ranging from 42 to 85 years. Postoperatively, there were no major complications such as postoperative infection or dislocation. All patients were followed for more than 4 months (mean 10.4 months). The JOA hip score averaged 89.4 points after surgery. More than 80% of the hips were rated as having an excellent or good result and there were no poor results.