When open reduction and internal fixation with plate and screws are indicated in comminuted proximal shaft of humerus, the ideal plate position at proximal end of the humerus is the lateral surface of the greater tuberosity. At midshaft of the humerus, however, insertion of the deltoid muscle limits the application of the plate on the lateral aspect. To overcome this discordance, open reduction and internal fixation for the treatment of comminuted fracture in the proximal humerus with precontoured spiral plate was performed to preserve deltoid insertion.

We performed open reduction and internal fixation with spiral plate in five patients. Two out of five required tricortical autogenous iliac bone graft due to severe comminution at the surgical neck. All patients were folllowed up for 20.5 months in average. The radiographic study for bony union and shoulder function ( Neer's criteria ) were evaluated.

All five fractures healed. Comminuted fracture at proximal humerus consolidated at 5 months in average. Comminuted fracture at the surgical neck needed an extra 2 months for healing. Shoulder function was classified as one excellent, two good and two fair. Two fair patients, who had severe comminution at the surgical neck, resulted in moderate loss of abduction and external rotation of the involved shoulder. But, the patients were satisfied with their shoulder function at final follow-up. There was no infection or metal failure.

We recommend spiral plate as a worthwhile treatment for comminuted fracture of proximal humerus. Preservation of deltoid insertion seems to be helpful in the recovery of shoulder function.