Surgical exposures of the humerus.

The neurovascular and muscular anatomy about the humerus precludes the use of a truly "safe" fully extensile approach. Working around a spiraling radial nerve at the posterior midshaft requires either a transmuscular dissection or a triceps-avoiding paramuscular technique. To gain maximal exposure, the radial nerve must be mobilized at the spiral groove. For exposure of only the proximal humeral shaft, many surgeons prefer the anterolateral approach because it uses the internervous plane between the axillary and deltoid nerves proximally and the radial and musculocutaneous nerves distally. Proximally, the deltopectoral approach to the shoulder continues to be the most widely used. However, the lateral deltoid-splitting approach is a viable, less invasive approach for both rotator cuff repair and fixation of valgus-impacted proximal humeral fractures. Distally, intra-articular exposure is dependent on triceps mobilization, either by olecranon osteotomy or triceps release; this exposure can be coupled with either a triceps-splitting or a paratricipital approach for proximal extension.