Final answer:
Anatomic landmarks to look out for when placing a proximal humeral locking plate include the medial epicondyle, lateral epicondyle, and lateral supracondylar ridge.
Step-by-step explanation:
When placing a proximal humeral locking plate, there are several anatomic landmarks to look out for. These include the medial epicondyle of the humerus, which is a prominent bony projection on the medial side. On the lateral side of the distal humerus, there is a smaller bony projection called the lateral epicondyle. Just above the lateral epicondyle is the lateral supracondylar ridge, a roughened ridge of bone. These landmarks are important for proper placement of the locking plate and also serve as attachment points for muscles that act on the forearm, wrist, and hand.