Pectoralis Major Tendon Avulsion from Rappelling

Military Medicine, Feb 2004 by Whitaker, Derek C, Warme, Winston J

To our knowledge, we are reporting the first case of a pectoralis major tendon avulsion from rappelling. The mechanism of injury in this case differs biomechanically from the commonly associated activity of bench pressing. The patient's initial presentation, course of corrective treatment, and postoperative rehabilitation is discussed in detail. A review of the historical and current literature on pectoralis major tendon injuries is included. The results of current biomechanical studies are discussed in relation to the complex anatomy of the pectoralis major muscle. This report is relevant to individuals involved in rappelling, high-demand athletes, and the surgeons who treat them. Nonoperative management of pectoralis major tendon tears is contrasted with operative repair. The current literature supports operative treatment in high-demand athletes, laborers, and military personnel to allow them to regain full strength and endurance.

Introduction

Rupture of the pectoralis major is an uncommon injury. Patissier1 presented the first case in 1822. Less than 100 cases have been reported to date.2"6 The majority of these injuries involves tears of the Inferior sternal fibers of the pectoralis major at or near the musculotendinous junction.2-5,7,8 Most reported ruptures occurred in weight lifters, and the bench-press exercise is the most common mechanism of injury. To date, there have been no reported tears of the pectoralis major muscle associated with rappelling. This article presents a case of an acute rupture of the pectoralis major tendon in a soldier who was rappelling in a U.S. Army air assault course. His written consent was obtained prior to publication of this report

Case Report

A 34-year-old right-hand-dominant active duty soldier was rappelling from a height of 70 feet when he quickly reached behind his back with his right hand to "brake" or slow his descent to avoid contact with another rappeller. he immediately felt a "pop" followed by excruciating pain in the right shoulder. he completed his descent without further injury, waited approximately 1 hour while the pain in his shoulder resolved to a dull ache, and attempted to make a second descent. On the second attempt, the pain associated with braking was exponentially worse, forcing the soldier to report to his troop medical clinic for treatment and orthopedic consultation.

The soldier is a recreational weight lifter who denied previous upper extremity injury or any recent consumption of fluoroquinolone antibiotics. he also denied using any performance-enhancing supplements including anabolic steroids, creatine phosphate, or androstenedione. he had no significant past medical or surgical history. On initial presentation, he was in moderate discomfort, standing with the right shoulder slightly lower than the left. There was marked ecchymosis on the medial aspect of his proximal right humerus (Fig. 1). There was diffuse swelling over the right pectoralis region with a palpable bulge within the muscle belly as well as mild asymmetry of the anterior axillary fold. This area was tender to palpation. The asymmetry of his anterior chest was accentuated by active abduction and adduction vs. resistance. His motor examination revealed weakness on adduction and internal rotation. His active range of motion was also limited in internal rotation secondary to pain. His neurovascular examination was normal. Radiographie examination revealed normal anterior-posterior, axillary, and scapular-Y views with no bony abnormality.

After discussing his treatment options at length, the patient elected to undergo a surgical repair, and informed consent was obtained. A 7-cm vertical incision was made over the anterior aspect of the proximal humerus above the bicipital groove. The deltopectoral interval was identified. The cephalic vein and deltoid muscle were retracted laterally. The superior three-fourths of the pectoralis major tendon, the entire sternal head, had avulsed off the bone. The inferior 5-mm cuff of tendon from the clavicular head remained intact. The middle and posterior laminar tendons were identified. The retracted edges of the manubrial and abdominal portions of the tendinous sternal head were secured with modified Mason-Alien sutures of no. 2 Ethibond and no. 2 Panacryl (Ethicon, Somerville, New Jersey). A 3-mm-wide by 5-cm-long trough was made in the proximal humerus just lateral to the biceps tendon at the anatomic insertion of the pectoralis major muscle. Three drill holes were made 5 mm lateral to the trough for passage and tying of the sutures (Fig. 2). The abdominal fibers were secured most posteriorly, and the middle laminar (sternal) attachment was tied more anteriorly. Postoperative treatment included right upper extremity immobilization in a sling for 4 weeks except for elbow and wrist range of motion exercises. During weeks 4 through 6, gentle passive range of motion was allowed. Isometric exercises began at 8 weeks. Light resistance commenced at 12 weeks, followed by heavy lifting at 4 months.2^4