Insertional footprint anatomy of the pectoralis major tendon

Correct anatomical repair of pectoralis major tendon injuries requires accurate identification of the humeral insertion site. In the absence of residual fibers at the insertion, proper placement requires knowledge of the anatomic relationships in the proximal humerus. This anatomic study attempts to measure these relationships and the dimensions of the insertional footprint to assist in surgical repair and reconstruction. Six matched pairs of cadaver proximal humeri were examined. All specimens were found to be in good condition and none were excluded. The proximal to distal length and maximum width of the pectoralis major tendon were measured at the humeral insertion with a digital caliper. The distance from the superomedial corner of the greater tuberosity to the superior aspect of the tendon insertion was also measured. The mean proximal to distal dimension of the pectoralis major insertion was 72.3+/-12.3 mm. The mean maximal thickness at the humeral insertion was 1.4+/-.2 mm. The distance from the superomedial corner of the greater tuberosity to the bony tendon insertion was 42.2+/-8.5 mm. The anatomic location of the humeral insertion of the pectoralis major tendon can be located in repair of pectoralis tendon injuries by referencing the superomedial corner of the greater tuberosity and the lateral lip of the bicipital groove. Findings in the present study will improve knowledge of the surgical anatomy relevant to repair and reconstruction of the pectoralis major tendon.