[Shoulder hemi-arthroplasty in proximal humeral fractures]

Most fractures of the proximal humerus with significant displacement are best treated surgically. The range of surgical treatment varies from closed reduction and pinning to hemiarthroplasty depending on the degree of displacement, age of the patient, and bone quality. Determining whether or not the individual fractured bone segments are displaced to a significant degree requires high quality x-rays which can be difficult to obtain from acutely injured patients. Indications for replacement of the humeral head in acute fractures include: head splitting fractures in elderly patients, Neer 4-part fracture dislocations, selected 3 part fractures and fracture dislocations in elderly patients with poor bone quality and a very small head fragment, selected severe impression fractures in elderly patients that involve more than 40% to 50% of the articular surface and selected anatomical neck fractures in which internal fixation is not possible. If a prosthetic replacement of the humeral head is chosen, secure repair of the tuberosities is essential to avoid tuberosity migration and malunion. The clinical results of prosthetic replacement of the proximal humerus for acute fractures are superior to those for late arthroplasty. This treatment modality has been proven to relieve pain. However, even for patients treated with primary arthroplasty, a restricted range of motion has to be expected postoperatively. Furthermore, several studies indicate that a significant number of complications can occur following early and late prosthetic replacement. Humeral head replacement as a salvage procedure after malunions or failed open reduction and internal fixation is technically demanding with a relatively high rate of complications. Newer implant designs and instruments may improve the clinical results.