Pectoralis major tear/rupture

The muscles situated at the front of the chest strengthen the chest cavity, serve as a strong protective shield and they are also a big part of securing shoulder and arm mobility and functionality. Chest muscles are the m. pectoralis major and pectoralis minor. Chest muscle  or tendon injuries in most cases reffer to injuries of the pectoralis major and its tendon. Pectoralis major performs internal rotation of shoulder and arm, it pulls the arm horizontally to the front and across the chest and pulls the arm from an above shoulder level position diagonally downwards.

Pectoralis major originates from the medial proximal part of the humerus, and it descends across the chest diagonally toward the sternum along whose lenght it connects. It has two parts, the strenal part, due to its connection to the sternum and the clavicular part, connected to the clavicle.

Pectoralis major tendon rupture is a rare occurence, it can be either partial or complete which is more common. It mostly affects the male population between 20-50 years due to the fact that they more often participate in activities where this type of injury can occur. Chest muscle tendon ruptures happen during explosive and sudden motions with heavy loads on the arm, shoulder or chest. They are a common occurence with weightlifters, eg. during bench press, they can also be common in wrestling, rugby or american football as a result of a direct trauma on the chest/shoulder/arm during falls or blows on them.

Depending on the location of the rupture, there are 4 types of it:

  1. Rupture at the origin of the pectoralis major tendon on the humerus

 2. Rupture at the musculo-tendon junction where the tednon tissue transforms into muscle tissue

  3. Rupture at the belly/middle of the muscle

  4. Rupture at the connection of the muscle with the sternum, ie. chest bone – extremely rare

Pain, located in the chest or upper part of the humerus, is very intense and a sense of tearing in the location of the tera can be heard and felt. There can be swelling and a hematoma, deformation of muscle or tendon tissue where the tear occured (convexity or concavity), muscle weakness, inability to lift the arm forward and diagonally infront of the body or to perform internal shoulder rotation. Arm and shoulder movement is limited.

Pectoralis tendon ruptures are treated depending on their gravity, ie. if they are partial or complete. With partial tears a conservative approach can be implemented, but with complete ruptures a surgical reconstruction, ie. connecting of the tendon has to be performed as soon as possible after the injury occured in order to prevent excesive tendon shortening. After the surgery the arm and shoulder should be immobilised to enable proper healing. Afterwards careful and progressive range of motion should be developed as well as muscle stretching and relaxing. Progressive muscle strengthening has to be implemented, first through static then dynamic exercises, without loads and later adding them gradualy and through concentric work in the beginning and eccentric work load in the latter stages of rehabilitation. Shoulder, chest and arm stability exercises should be a part of the rehabilitation process to ensure full functionality and return to normal activities which is expected after cca. 3-4 months.