What is the insertion point of the triceps brachii?

• A. Olecranon tuber
• B. Radial and ulnar tuberosity
• C. Distal phalanx II-V
• D. Caudal border of the scapula

Answer: (A)

The triceps brachii muscle has its insertion point at the olecranon tuber of the ulna. This anatomical feature is significant because the olecranon serves as the bony prominence of the elbow, providing leverage for the muscle to extend the forearm at the elbow joint. Given the function of the triceps brachii, which is primarily to extend the elbow, this insertion is ideally positioned to facilitate that movement.

The other options do not accurately represent the triceps brachii's insertion point. The radial and ulnar tuberosities are locations where the biceps brachii attaches, not the triceps. The distal phalanx of fingers II-V relates to the flexor tendons and other muscles involved in finger movements, quite unrelated to the triceps. Similarly, the caudal border of the scapula pertains to the attachment of different muscles, primarily those associated with shoulder movements rather than elbow extension.