Rupture of the distal tendon of the biceps brachii. A biomechanical study.

In biomechanical studies on ten patients who had had a rupture of the distal tendon of the biceps brachii, we compared the results of immediate anatomical reattachment, delayed reattachment, and conservative treatment. When the tendon was simply attached to the brachialis muscle (one patient), there was nearly normal strength in elbow flexion but about 50 per cent loss of forearm supination. Late reinsertion (one patient) improved strength of both flexion and supination, but not to normal. Immediate reattachment (four patients) restored normal strength in flexion and supination at one year but not at four months (one patient). With conservative treatment (three patients) there was a mean loss of 40 per cent of supination strength and variable loss of flexion strength, averaging 30 per cent. These data suggest that immediate surgical reinsertion of the biceps tendon into the radial tuberosity, compared with other modes of treatment, restores more strength of flexion and supination.