We investigated the clinical results of humeral head replacement and the influencing factors affecting the results. Twelve shoulders of 11 patients were followed-up. Six patients were male and 5 patients were female. Humeral head replacement was performed on these patients. The patients' age at operation averaged 56.3 years. The follow-up period ranged from 8 months to 17 years and 8 months (average 4 years 1 month). Preoperative diagnosis was dislocation fracture of the proximal humerus in 6shoulders, non-union in 2 shoulders and avascular necrosis of the humeral head in 4 shoulders. The operative results were evaluated according to the shoulder evaluation sheet of the Japan Orthopaedic Association. (JOA score).
The average postoperative JOA score was 69.8 points (46-97 points). The average shoulder elevation was 84.6±39.1°. The roentgenograms showed an inferior subluxation in 4 shoulders. The average points of the JOA scores of 4 shoulders with underlying complications such as other injuries and axillar nerve palsy was 59.5±9.3 points. In 8 shoulders without such complications, the averages of the JOA scores was 74.9±16.4 points. The averages of the elevation angle in shoulders with an inferior subluxation was 56.3±17.9°. The average of the elevation angle in shoulders without an inferior subluxation was 96.3±41.4°.
From the results of this study, it can be concluded that the prognosis is poor for patients with underlying complications and an inferior subluxation.
