Pectoralis Major Rupture: Ensuring Accurate Diagnosis and Effective Rehabilitation
Janus D. Butcher, MD; Andrew Siekanowicz, MD; Frank Pettrone, MDTHE PHYSICIAN AND SPORTSMEDICINE - VOL 24 - NO. 3 - MARCH 96
In Brief: Rupture of the pectoralis major muscle and tendon, which occurs most frequently among weight lifters but has been reported in many sports, can most often be diagnosed based on the history and physical exam. Surgical intervention for complete ruptures has a clear advantage over conservative therapy. Athletes of all levels can be expected to return to near preinjury levels of participation following surgery and a well-constructed, supervised rehabilitation program. This should involve immobilization followed by range-of-motion exercises and strength training of gradually increasing resistance.
Rupture of the pectoralis major can be a devastating injury in an active person. While it is relatively uncommon, clinical experience indicates that it probably occurs more frequently than the literature suggests. Recent reviews (1-14) have reported fewer than 100 cases, mostly involving complete avulsion of the pectoralis tendon from the humerus. Recognition of an acute pectoralis major rupture and early surgical intervention followed by a well-structured rehabilitation program are crucial to ultimate functional recovery. The two cases described below exhibit typical injury histories but very different management strategies and outcomes.
Case 1: Pole-Vaulter
A 21-year-old, right-handed, world-class pole-vaulter reported right arm pain following a tearing sensation as he completed the eighth repetition of his third set of bench pressing 175 lb. He felt generalized weakness in his right arm and noticed immediate swelling in his right anteromedial chest. He denied anabolic steroid use.
Examination revealed a very firm 10-cm mass on the anteromedial chest wall, with ecchymosis and soft-tissue swelling in the proximal arm and axilla. A defect in the anterior axillary border was palpated. Strength testing demonstrated marked weakness in arm adduction, forward flexion, and internal rotation. The patient's range of motion (ROM) was significantly limited because of pain.
Open exploration revealed a complete avulsion of the pectoralis major tendon from its insertion on the proximal humerus. The tendon was identified and reattached to its normal insertion just lateral to the bicipital groove using suture anchors.
The athlete's arm was immobilized using a sling and swath for 10 days postoperatively, after which gentle ROM exercises were initiated. He started progressive weight training with wrist curls and elbow flexion and extension 4 weeks after surgery. Resistance exercises involving internal and external rotation and light bench pressing were added at 6 weeks. The patient had significant strength gains and full ROM 10 weeks postsurgery. He had full strength (equal to the unaffected arm) 4 months postoperatively and had returned to pole vault training at that time (figure 1).
Case 2: Body Builder and Rower
A 28-year-old left-handed body builder and competitive rower felt a tearing sensation and experienced severe pain in his right arm during a maximal bench press of 450 lb. Ecchymosis and swelling rapidly developed in his axilla and chest, and he noticed a peculiar bulge in his medial chest. He was evaluated and told he had a partial tear of his pectoralis major muscle; conservative measures were prescribed.
Two years after the injury, he reported significant right-arm weakness that prevented him from weight training. He was able to continue rowing, although not competitively. He also complained of the cosmetic effects of the injury. At the time of his reevaluation, he had significant asymmetry in his chest with the loss of the right axillary border (figure 2a), axillary webbing (figure 2b), and an anteromedial chest wall mass with flexion and resisted internal rotation (figure 2c). Isokinetic testing revealed a 27% work deficit in internal rotation and a 29% work deficit with adduction compared with the unaffected arm. He, too, denied anabolic steroid use.
The patient elected to undergo surgery, which revealed evidence of a previous complete avulsion of the right pectoralis major tendon. The free edge of the pectoralis muscle was adhering to the anterior deltoid without appreciable remaining tendon. Because of the absence of tendon and the significant adhesion between the muscles, it was determined that reconstruction was not feasible.
Anatomy and Function
The pectoralis major functions in arm flexion, internal rotation, and adduction (figure 3: not shown). It is a broad, flat muscle that originates from two heads: the clavicular head, which arises from the proximal portion of the clavicle, and the sternocostal head, originating from the sternocostal cartilage of the second through sixth ribs. The muscle traverses the anterior chest wall and overlies the pectoralis minor, producing the typical upper-chest contours. It then forms the anterior border of the axilla before terminating as a flat tendon inserting onto the lateral edge of the bicipital groove on the proximal humerus.
Typical Injury Patterns
Ruptures and tears of the pectoralis major are most commonly seen in weight lifting but have been reported in many other sports, including wrestling, rodeo, football, boxing, water skiing, and sailboarding (1-5). Most of these injuries occur in athletes in their third or fourth decade of life. To date, ruptures have not been reported in female patients; however, with the growing interest in weight training and body building among female athletes, this may change.
Injuries can occur at any point from the origin to the insertion and are graded based on the site and degree of the tear. A grade 1 injury is a contusion or strain without tearing. Grade 2 injuries are partial tears, usually of the muscle body or musculotendinous junction. Although grade 2 injuries produce less functional impairment than a complete rupture, the resulting weakness can considerably impair an active patient's ability to train and compete. Finally, grade 3 injuries are complete tears of the musculotendinous junction or an avulsion of the tendon. Most complete tears involve an avulsion of the tendon from the humerus.
Separate processes may account for tendon ruptures and midsubstance tears. The typical mechanism for tendon or musculotendinous junction injury is excessive tension from acute overload of an eccentrically loaded tendon, as occurs in bench pressing (6): As the weight is lowered to the chest, fibers originating from the sternal head are maximally stretched. During the deceleration and early lift phase of this exercise, the fibers can be overstretched, leading to failure of the viscoelastic force and rupture (7). In contrast, complete tears of the muscle body are commonly caused by direct trauma (8,9).
One theory suggests that tendons may not be able to adjust to the increasing muscle mass and decreased flexibility associated with weight training (4). This may be particularly true with rapidly changing muscle mass when a person uses anabolic steroids or growth hormone. Therefore, this injury should raise suspicion of anabolic steroid use, particularly in body builders (4).
The patient usually has no warning of impending rupture. In most cases there are no preceding complaints relating to pectoralis problems. The patient experiences an abrupt tearing sensation and pain in the affected arm and chest wall and may report hearing a pop when the injury occurs. Swelling and ecchymosis develop rapidly in the axilla and lateral chest; they will, however, be absent in patients who have chronic ruptures.
Physical examination demonstrates an obvious defect in the anterior axillary border. A mass may be appreciated in the anteromedial chest wall when the pectoralis muscle is flexed (figure 2a). This can be demonstrated by having the patient press his or her hands together in front of the abdomen (figure 2c). Weakness in adduction, internal rotation, and flexion of the arm is universal. The patient will generally have limited ROM due to pain. Axillary webbing—the accentuation of the inferior margin of the anterior deltoid with the loss of the pectoralis—may be seen as swelling decreases (figure 2b). Grade 1 and grade 2 injuries without significant tearing may produce local swelling and ecchymosis but no defect in the axillary border.
Plain radiographs are not uniformly helpful but will often demonstrate an absence of the pectoralis shadow on the anterior chest wall. Magnetic resonance imaging (MRI) has been reported to be useful in the diagnosis, but the high cost of this procedure and the overt physical findings in most cases limit its clinical utility. MRI may be helpful in differentiating partial from complete tears and in defining the location of the tear when this information is relevant to surgical planning (10).
Determining the degree of tear may be difficult in the acute injury because of swelling, muscle spasm, and ecchymosis. Repeated clinical evaluation as the swelling decreases will allow accurate grading of the severity and location of the tear.
Treatment Usually Surgical
Surgical treatment of complete pectoralis major ruptures has a clear advantage over conservative management in athletes and anyone who would be impeded by loss of strength (1-14) Pectoralis ruptures have been successfully repaired following delays of up to 5 years after injury, but best results are achieved with prompt recognition and surgery (14).
Although good functional results are reported in conservative therapy, these patients experience a residual loss of strength in arm adduction, flexion, and internal rotation. Wolfe et al (7) reported a 26% loss of peak torque and a 39.9% work deficit in arm adduction in unrepaired pectoralis major ruptures. In contrast, patients who had surgical repair had no residual strength or power deficits. Overall, the functional results in surgical intervention have been shown as 80% excellent, 10% good, and 10% unreported; whereas conservative management showed 17% excellent, 58% good, 17% fair, and 8% lost to follow-up (13).
The two cases presented earlier demonstrate the differences in the two treatment approaches quite well. The athletes sustained similar injuries. Their sports differed, but both activities require a great deal of upper-extremity strength. The patient in case 1 returned to full participation following surgery, while the second athlete was unable to return to his preinjury level.
Athletes are often unhappy with the cosmetic consequences of the injury as well, which can eliminate an athlete from competition in sports such as body building (4,7). Most of the cases in which this has been mentioned have reported good cosmetic results following surgery (1-10,12-14).
Although an argument for conservative therapy in sedentary people can be made, early surgical repair in the athlete is the general consensus in the literature. Therefore, all active patients who have acute pectoralis major rupture should be referred for early surgical consultation. Several techniques have been described for both midsubstance and tendon avulsion injuries.
Grade 1 and grade 2 injuries without significant tearing can be treated conservatively with pain-relieving measures followed by range of motion. Return to play usually takes 1 to 3 weeks. More significant grade 2 tears often require the same treatment as grade 3 injuries.
Rehabilitation and Return to Play
Postoperatively, the patient's arm and shoulder are immobilized using a sling and swath for 10 to 14 days, followed by gentle shoulder ROM exercises. Light resistance exercises are gradually added, concentrating on shoulder flexion initially and progressing to adduction and internal rotation over 5 to 7 weeks. At approximately 10 weeks after surgery, light bench pressing is added, gradually increasing in resistance. Patients should be cautioned strongly against "working through" pain in the arm or chest; they should be instructed to alter their rehabilitation if symptoms develop. Full return to athletic training is allowed when full range of motion and strength, as compared with the unaffected side, are attained.
Early, Straightforward Recognition
Pectoralis major injuries can be devastating to athletes at all levels. These injuries are readily identifiable by clinical presentation and rarely require expensive diagnostic imaging tests. Early recognition followed by surgical intervention and a well-structured rehabilitation program are crucial to returning athletes to their preinjury levels of participation.
Dr Butcher is the director of primary care sports medicine in the Department of Family Medicine at the Dwight D. Eisenhower Army Medical Center in Fort Gordon, Georgia. Dr Siekanowicz is an orthopedic surgeon in private practice with Kinston Orthopedic and Sports Medicine Center in Kinston, North Carolina. Dr Pettrone is an associate professor of orthopedics in the Department of Orthopedics at Georgetown University in Washington, DC. Address correspondence to Janus D. Butcher, MD, Dept of Family Medicine, Dwight D. Eisenhower Army Medical Center, Fort Gordon, GA 30905-5650.