What neurovascular structures are of concern with proximal humerus fractures?

Proximal humerus fractures are significant injuries that can lead to various complications involving neurovascular structures in the shoulder region. The correct identification of the structures at risk is crucial for preventing complications and ensuring proper management.

The axillary artery and axillary nerve are particularly important to consider in the context of proximal humerus fractures. The axillary nerve innervates the deltoid muscle and the teres minor muscle and provides sensation to the skin overlying the deltoid. It runs in close proximity to the surgical neck of the humerus and is susceptible to injury during a fracture in this area. Compression or transection of the axillary nerve can lead to shoulder weakness and loss of sensation in the lateral shoulder region.

The axillary artery is also at risk, especially in fractures that involve significant displacement or when fragment stabilization is challenging. Damage to the axillary artery can result in significant hemorrhage and compromise the blood supply to the arm.

In contrast, the other neurovascular structures mentioned in the other options are either not located near the proximal humerus or have a different anatomical relevance that does not make them as critical as the axillary artery and nerve in the context of these types of fractures. Understanding the anatomy and potential complications is essential for effective