Short head of biceps brachii

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The short head inserts distally on the tuberosity while the long head inserts proximally closer to the apex of the tuberosity.

The bicipital aponeurosis, also called the lacertus fibrosus, is a thick fascial band that organizes close to the musculotendinous junction of the biceps and radiates over and inserts onto the ulnar part of the antebrachial fascia.

The tendon that attaches to the radial tuberosity is partially or completely surrounded by a bursa, the bicipitoradial bursa, which ensures frictionless motion between the biceps tendon and the proximal radius during pronation and supination of the forearm.

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