Existing classifications of fractures of the head of the humerus are inadequate in terms of interobserver reliability and the predictability of the clinical outcome. From a combined study of 73 fracture specimens in museums and 84 CT-three-dimensional reconstructions in patients, we have devised a classification which appears to be more useful clinically. Common patterns of fracture and a plausible mechanism of injury were observed.

In 3-D most proximal humeral fractures can be organised into five basic types. These correspond in some degree to the Codman/Neer classification, but differ significantly in regard to the more complex patterns of fracture. We observed a logical progression from simple to complex fractures. An interobserver reliability study was carried out which indicated the improved usefulness of this new 3-D concept in providing a common language among clinicians for classifying these injuries. When surgery is indicated, the 3-D concept is also invaluable in guiding the restitution of anatomy through either open or percutaneous means.

Complex fracture patterns of the proximal humerus can be difficult to understand and to treat. Classification systems are inadequate and the exact mechanisms of injury are obscure. From inspection of 73 cases of proximal humeral fractures culled from a large number of museum specimens, we propose a hypothesis as to the nature and configuration of these injuries. It is suggested that the glenoid is the “anvil” upon which the humeral head is broken and that the particular fracture personality reflects the position of the head vis a vis the glenoid at the time of injury. From this perspective, proximal humeral fractures present in a comprehensible and progressive sequence. Five different fractures patterns are identified and account for the vast majority of these injuries. X-ray examination, especially CT 3-D reconstructions, in a small group of clinical cases (30 patients) substantiated the usefulness of looking at these fractures in this way. From a combination of the museum studies and patient material, we have constructed a “fracture wheel” diagram for the presentation of these injuries in a format which may be helpful in organizing a new and clinically useful classification system.