Pec Major Tear or Rupture (Pectoralis Major Tear or Rupture).
The pectoralis major (pec major) muscle lies at the front of the chest. It helps bring the arm forward (during a press up and bench press), brings the arm from the side towards the chest (during a shoulder dip) and rotates the upper arm inwards (internal rotation). As well as being a powerful muscle it is important in contributing to the appearance of the chest and upper arm.
Because of the power and structure of the muscle and the increased participation in sports involving weight lifting and training the frequency of pectoralis major (pec major) injuries has increased dramatically in recent years.
The pectoralis major muscle (pec major) is a fan shaped muscle that originates from the collarbone (clavicle) and from the breastbone (sternum). It then passes to the upper arm (humerus) where it attaches just in front of the Long Head Biceps (LHB) tendon as it passes down the arm from the shoulder. The pectoralis major (pec major) has a number of heads or points of origin that converge to attach to the upper arm in 2 layers. Traditionally the muscle and its tendon were considered to twist to produce the dual layered insertion but more detailed anatomical studies suggest that the insertion pattern is produced by a layering of the tendon rather like the sticks or ribs of a Japanese hand fan.
Pectoralis muscle injury
Strains of the muscle in which the tendon attachment remains intact normally settle with conservative management in the form of rest, ice, rehabilitation, analgesics and anti-inflammatories. However, the tendon may tear or become detached from the arm bone (humerus).
Tears of the pectoralis major (pec major) muscle typically occur near the attachment of the tendon to the arm bone (humerus) and may be full thickness, affecting both layers of the attachment, or partial thickness, affecting only one layer. The tear may also be complete involving the full width of the tendon or incomplete effecting only a portion of the attachment. Once the attachment of the tendon is torn it will not reattach to the humerus itself and may require surgical re-attachment. Detachment of the origin of the pectoralis major (pec major) from the sternum is rare and does not typically require surgical treatment.
Tears of the pectoralis major (pec major) typically occur in active men aged 20 to 40 years. The tear is typically caused by an indirect injury to the arm. Typically it occurs during a forced contraction of the muscle during a sporting or weights related activity, such as a bench press (48% of all cases).
Although anabolic steroid use has been linked with tears of the pectoralis major there is no proven correlation.
A tear of the pectoralis major muscle is typically associated with the sudden onset of pain in anterior chest wall or upper arm during a forced contraction of the muscle, typically a bench press or similar activity. The pain is usually marked and prevents continuation of the activity or the weights to be dropped.
There is usually associated weakness of the shoulder and arm.
There may be significant bruising both to the chest wall and arm. This bruising may track down the arm to the elbow or wrist.
There may be a significant change in the appearance of the chest wall and upper arm. The pectoralis major (pec major) muscle may be more prominent over the chest wall as the tendon rupture and retraction allows the muscle to bunch up. There may be a reduction or thinning of the fold of tissue in front of the armpit and upper arm (the anterior axillary fold) as the tendon retracts towards the chest.
Diagnosis and Investigation
The diagnosis may be apparent from the history and examination. In a complete tear the diagnosis tends to be more obvious but partial tears may be more difficult to identify. Further investigations may be undertaken to confirm the diagnosis and to exclude additional pathology.
Plain radiographs (X-Rays).
Radiographs of the shoulder are typically taken but are often unremarkable. These may demonstrate that the pectoralis major tendon has pulled off with a piece of bone (avulsion fracture).
Ultrasound scan (USS) or Magnetic Resonance Imaging (MRI) scan.
Scans may be arranged to identify structural damage to the pectoralis major muscle or injuries to the adjacent structures such as the rotator cuff.
Rest and avoidance of exacerbating activities.
Rest will typically allow the pain associated with a pectoralis major (pec major) tendon tear to settle. Weakness and the cosmetic deformity will typically persist.
Analgesia Anti-inflammatory medication.
Anti-inflammatories eg: Ibuprofen, Diclofenac and VoltarolTM may be helpful in addition to simple painkillers (analgesia) eg: Paracetamol.
Rehabilitation and physiotherapy.
Physiotherapy may be helpful to maintain range of movement and
condition the shoulder. The weakness and cosmetic deformity will typically persist.
Pectoralis major (pec major) tendon detachments from the arm bone (humerus) do not reattach spontaneously or with non-operative management. In the absence of surgical repair weakness and cosmetic deformity are likely to persist. The injury typically occurs in young active individuals and surgery is frequently indicated.
The surgery typically involves a 5-7cm scar over the front of the upper arm. The torn tendon is identified and repaired back to the upper arm (humerus).
Link to Pec (Pectoralis) Major repair surgery.
Complications with surgery of this type are uncommon but may include failure of repair.
Following the surgery the arm is typically immobilized in a sling for a period of 2 to 6 weeks. A progressive and supervised rehabilitation program typically allows range of movement and strength to be regained. It may be 3 to 6 months before you return to manual work or contact sports and heavy weights. Compliance with the rehabilitation program will affect the outcome of the surgery undertaken.
Surgery typically improves the pain, strength and the cosmetic appearance associated with a pectoralis major (pec major) rupture improving function and the probability of returning to sporting activities.