We investigated the clinical course of each age-group following hemiarthroplasty for a displaced fracture of the proximal humerus. There were 13 patients with 15 shoulders (mean age at injury: 77.5 years old,1 man and 12women) who underwent surgery for a displaced fracture of the proximal humerus. All patients were operated on by hemiarthroplasty. We divided 15 shoulders into 3 groups by age at injury. There were 3 shoulders in the seventh decade group,5 shoulders in the eighth decade group and 7 shoulders in the ninth decade group. We investigated the shoulder function using the Japanese Orthopaedic Association (JOA) score and shoulder flexion at 3 months,6 months, and 12 months postoperatively. In the seventh decade group, the JOA score was 77 points,90 points, and 98 points (3 months,6 months, and 12 months postoperatively: the same as above) and shoulder flexion was 98 degrees,110 degrees, and 150 degrees. In the eighth decade group, the JOA score was 71 points,85 points, and 88 points, and shoulder flexion was 82 degrees,95 degrees, and 118 degrees. In the ninth decade group, the JOA score was 69 points,75 points, and 76 points, and shoulder flexion was 71 degrees,81 degrees, and 83 degrees. Functional recovery improved up until 12 months after hemiarthroplasty and the outcome was the most excellent in the seventh decade group. Remarkable functional recovery was not obtained after 6 months postoperatively in the eighth decade group and ninth decade group. So, early time exercises before 3months postoperatively were very important for functional recovery in patients more than 70years old.
