Tears of the pectoralis major tendon are an uncommon, but significant, injury to the shoulder. The pec major is a major shoulder muscle, and the shoulder becomes much weaker if it is torn. Therefore, all Pectoralis Tendon Tears should be surgically repaired, except in the infirm.
The Pectoralis Major is the main muscle of the chest. It attaches via a tendon (rope) to the humerus (arm bone). The most common site of rupture is when the tendon tears away from the bone. The other potential site of injury is when the tendon itself tears, near where this tendon emerges from the muscle.
There are two parts to the pec major. The one that commonly ruptures is the deep part, which has over 80% of the Pec’s muscle fibers. The small superficial portion often remains intact, giving the false impression that nothing is torn and making it difficult to diagnose this injury on physical examination. Diagnosis can be especially difficult during the first three weeks following injury, when swelling can make palpation difficult. Sometimes the injury is obvious because a ball forms in the chest when the muscle retracts and the front of the armpit has a noticeable change in appearance. However, in many cases the injury is not totally obvious; in these cases an MRI is very helpful in confirming the diagnosis.
Pectoralis Major Tendon tears are repaired as an outpatient procedure through a cosmetic incision over the pectoralis tendon. When the tendon itself is torn, it is repaired with strong sutures. When the tendon is torn from the bone, it is repaired back to the bone using 3 bone anchors (VIDEO). Bone anchors are harpoon-head shaped devices with strong suture in them, used to repair tendons back to bones. They provide strong fixation. The rate of re-tear following repair is 0-8%.
The best results occur with early surgery, within the first month (or two) following injury. Early Pectoralis Major Tendon repair often leads to full recovery of strength. However, even in cases where significant time has elapsed, it is still advisable to repair this tendon. For surgical repairs performed at a later date, some (average 6%) loss of strength is common. In these long-standing cases, part of the torn tendon may have resorbed, and a tendon graft (from someone who no longer needs it) may be required to bridge the resulting gap between the tendon and bone. Without repair a permanent 30% loss of strength will occur. So even late Pectoralis Major Tendon repairs do better than leaving it unrepaired. Studies have shown that surgical repairs of the Pectoralis Major Tendon regains strength, decreases pain and leaves patients more satisfied; in these studies, 88-90% that had a surgical repair were satisfied vs only 17-27% who elected to not undergo surgical repair.
After surgery, leave the dressings on and keep the wound clean and dry for 24 hours. Before 24 hours, bathing is fine; just keep the shoulder above water and don’t get the dressings wet. After 24 hours the dressings can be removed and the incision can get wet in the shower. Blot it dry. There are no stitches to remove (they’re buried and absorbable). There’s a piece of tape over the wound. The tape will fall off when it’s ready. The longer it stays on, the nicer the final wound may look. Please don’t submerge the incision under water (like swimming, or putting your hand under water) for 10 days after surgery. The elbow, wrist, forearm and hand can be moved early on to prevent stiffness.
After surgery, a shoulder immobilizer or sling is worn for 6 weeks. A home motion program and physical therapy is required. At 6 weeks, the arm can be used for light activities. Most activities can be performed at 3 months, with heavy activities allowed at 4 months after surgery. Weight lifting and sports are allowed at 5-6 months.
Pectoralis Major Tendon tears are a serious injury that are best treated early by an experienced surgeon. In good hands, the results of surgical repair are excellent.