Modified pectoralis major myocutaneous flap with partial preservation of the muscle: a study of 55 cases.

The results of a technical modification of the pectoralis major myocutaneous flap are presented in which the clavicular bundles, the first two or three sternocostal bundles, and the lateral border of the muscle were preserved. The flap was delivered into the neck through a subclavicular tunnel. The procedure was performed in 55 patients, with a bilateral simultaneous flap used in one. Four instances of flap necrosis occurred, although it was felt that they were not related to the modified technique, and no damage to the subclavian vessel occurred. In the first 25 flaps, we did not identify the neurovascular bundle supplying the preserved musculature. Eighteen of these flaps were evaluated, and atrophy was encountered in 10. Of the latter 31 patients, only one suffered atrophy of the sternocostal bundle. The technical modification of preserving part of the muscle and its neurovascular supply is especially important in manual workers. Twenty-eight of 38 patients with preserved muscle function at the donor site were manual workers, and 10 of them returned to normal activity. None of the patients who developed atrophy of the pectoralis major muscular remnant was able to return to work within 1 year or longer after treatment. In the successful cases, there were no functional sequelae of the arm, visible depressions in the infraclavicular area, or loss of the anatomic configuration of the anterior axillary line.