Extension (Or Straightening) of the Elbow Stops When the Proximal

Question

Extension (or straightening) of the elbow stops when the proximal end of the ulna engages the .
A) olecranon fossa of the humerus
B) coronoid fossa of the humerus
C) medial epicondyle of the humerus
D) trochlea of the humerus

Accepted Answer

The olecranon fossa of the humerus is where the proximal end of the ulna fits when the elbow is fully extended. This anatomical feature prevents further extension, acting as a physical stop.