Aim: To evaluate the results of internal fixation of displaced proximal humeral fractures with a locking plate system.

Material and Methods: Between 2002 and 2003, 126 patients presented to our shoulder unit with proximal humeral fractures. Of these, 22 healthy active patients with displaced two to four-part fractures underwent open reduction and internal fixation with a locking compression plate system (Philos, Stratec UK Ltd). Their average age was sixty-two years. They were evaluated clinically and radiologically at 4, 12, 26 weeks or until union. Objective assessment was measured by the Constant scoring system, subjective assessment by the Oxford shoulder questionnaire.

Surgical Technique: Through an anterior deltopectoral approach, the fracture was reduced. A titanium plate designed to contour over the lateral aspect of the humeral head was applied with minimum of five locking screws in head fragment and three in the humeral shaft. Tuberosities approximation was reinforced with Ticron sutures through the rotator cuff and the holes in the plate. The shoulder was immobilised in a sling for two weeks followed by gradual mobilisation program with the physiotherapist.

Results: All fractures united with a mean healing time of fourteen weeks. There were no malunion, non-union or failure of fixation. The mean constant score was 78. The average range of flexion was 1330, abduction of 1250 and external rotation of 430. One patient had a significant fall three months after surgery and sustained an undisplaced fracture of shaft of humerus below the plate. Treated non operatively, both fractures went on to uneventful union.

Conclusions: Internal fixation with locking plate system in healthy active patients, disregarding their age, is a reliable method of treating displaced proximal humerus fractures. In our experience, the functional outcome of these patients was superior to those patients treated with hemiarthroplasty or intramedullary fixation.