Anatomy and ultrasound of the anterior aspect of the elbow by Pr Marie Faruch

Distal biceps brachii tendon:
To analyze the distal tendon of the biceps brachii, I suggest starting with an axial section at the musculotendinous junction.
At the musculotendinous junction, we can identify a thin aponeurotic expansion that starts on the medial edge of this musculotendinous junction, the lacertus fibrosus that will cover the neurovascular bundle of the median nerve and the brachial artery to terminate on the antebrachial fascia.
Staying with the axial section, proximally we can use small movements to play with the anisotropy to see the two portions of the biceps tendon: the short head of biceps is located on the medial side and the long head of biceps is located on the lateral side. If we then slide the probe down, we can see that these two tendons have switched positions: the short head of biceps is now superficial and the long head is deeper.