Most fractures of the proximal humerus with significant displacement are be
st treated surgically. The range of surgical treatment varies from closed r
eduction and pinning to hemiarthroplasty depending on the degree of displac
ement, age of the patient, and bone quality. Determining whether or not the
individual fractured bone segments are displaced to a significant degree r
equires high quality x-rays which can be difficult to obtain from acutely i
njured patients. Indications for replacement of the humeral head in acute f
ractures 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 frac
tures 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 treat
ed with primary arthroplasty, a restricted range of motion has to be expect
ed postoperatively. Furthermore, several studies indicate that a significan
t number of complications can occur following early and late prosthetic rep
lacement.
Humeral head replacement as a salvage procedure after malunions or failed o
pen reduction and internal fixation is technically demanding with a relativ
ely high rate of complications. Newer implant designs and instruments may i
mprove the clinical results.