It is made up of 2 main muscles – the pectoralis major, the larger muscle of the pectoralis which helps to move your arms in front of your body, and the pectoralis minor, the smaller of the 2 pectoralis muscles and it helps to move the shoulder blades forward. Both muscles are important in ensuring a good range of motion and strength in the arms and shoulder.

A pectoralis major rupture is a rare injury that occurs when the tendon or muscles associated with the pectoralis major gets torn or ruptured. 

A pectoralis major rupture can occur in 4 areas, these are:

• Tendon tears or ruptures off the arm bone
• Tear or rupture where the tendon and muscle connect
• Tear or rupture within the pectoralis major muscle
• Tear or rupture of the muscle from the breast bone

Pectoralis major rupture is caused by:

• Weightlifting: particularly bench press exercises, where heavy weights are lifted predominantly with the pectoralis major. This might cause the tendon or muscles of the pectoralis major to snap or rupture.
• Contact sports: sports such as football, wrestling, or rugby can cause the tendon or muscles of the pectoralis major to rupture or tear.
• Injury: trauma or accidents can also cause pectoralis major rupture.

• Severe pain in your chest muscles
• Popping sound when the pectoralis major ruptures
• Pain or weakness in upper arms
• Bunching or lumping of the pectoralis major
• Bruising or swelling  

This is accompanied by loss of strength in the chest and upper arm muscles, bruising, and bunching up of the pectoralis major muscle.

• Age: men between the ages of 20 to 40 are more prone to a pectoralis major rupture.
• Gender: while it can also happen in women, a pectoralis major rupture is more commonly seen in men.
• Weightlifters: weightlifters, especially those who bench press very heavy weights are at high risk of a pectoralis major rupture.
• Athletes or hobbyists: participating in certain sports such as wrestling, football, rowing, rugby, etc increase your risk of a pectoralis major rupture.
• Steroids: research has shown that individuals who consume steroids are at a higher risk of a pectoralis major rupture. This is because steroids grow muscles bigger and disproportionately compared to the size of tendons, resulting in tendons unable to withstand the heavy weights that muscles can, causing them to rupture. 

• Physical examination: during your physical examination, it is important to inform your orthopaedist on how the injury occurred. Your muscle strength will be tested and your orthopaedist will palpate the area for signs for a tear or rupture.
• Magnetic resonance imaging (MRI): an MRI will be conducted to identify the area of rupture and its severity, such as a partial tear or complete rupture. 
• X-ray: an x-ray will be used to rule out other issues such as shoulder injuries.

Treatment options include:

• Non-surgical: recommended for older individuals and for those with a sedentary lifestyle. Rest and ice the area to allow the area to heal. Use non-steroidal anti-inflammatory drugs (NSAIDs) and painkillers to reduce inflammation and alleviate pain.
• Surgical: surgery, also known as a pectoralis major repair, can be performed on young and active individuals. Depending on where the rupture occurred, the area will be repaired before rehabilitation can occur.
• Physiotherapy: this option is advised for all individuals regardless of treatment option (surgical or non-surgical). Physiotherapy involves the use of gentle and therapeutic exercises to strengthen and rehabilitate the area.