Natural history of complex fractures of the proximal humerus using a three-dimensional classification system.

We studied the nonoperative treatment of proximal humeral fractures in severe injuries usually treated surgically. The natural history of 63 patients was followed prospectively for 2 to 9 years (mean, 42 months) with a nonrandomized protocol. A 3-dimensional classification system based on computed tomography scans was used to categorize the fractures.