YOUR HEALTH:
SPORTSMEDICINE UPDATE

By Dr. Robert Martin

Shoulder Impingement

One of the most common complaints in any orthopaedic practice is shoulder pain. The most common cause of shoulder pain is problems related to a complex structure know as the rotator cuff. The rotator cuff is commonly injured in overhead or throwing sports and thus gets mentioned regularly in the sports media. If you doubt this theory just watch Sports Center for one week and I can almost guarantee a reference to someone’s injured rotator cuff. Last year alone Greg Norman, Pete Sampras, 3 MLB pitchers and many more all had significant rotator cuff injuries, some requiring surgery. So why is this so common. It has to do with two factors, one is the design of some shoulders and the other is the way we use our shoulders.

The shoulder starts with the scapula or shoulder blade which is suspended on the back by 21 muscles (the only bone connecting the scapula to the body is the clavicle or collarbone). Articulating in a shallow socket in the scapula (called the glenoid) is the humerus or arm bone. The fact that the glenoid is shallow (about the curve of a coffee cup saucer) allows to arm to move through a wide and free ranging motion pattern. Off the back of the scapula is a projection of bone that forms a hood over the shoulder joint. This bone is called the acromion. Three muscles that begin on the scapula form a common tendon which is the rotator cuff attaching to the humerus. A major portion of the rotator cuff passes directly underneath the acromion. In doing so the rotator cuff is protected yet in another way it is confined and at times compressed as the arm moves above shoulder height. This compression of the rotator cuff between the humeral head and the acromion is known as Impingement Syndrome and results in progressive wear even tearing of the rotator cuff tendon. In most people this process starts with mild symptoms of shoulder pain many times coming and going over months or years. Typically this pain is worse with reaching above shoulder height, reaching behind the back or lying on the shoulder. Often this is referred to as bursitis. Impingement is more likely to occur in people with a particular shape to their acromions. Acromions that are flat rarely cause problems however acromions that are curved down in the front compress the rotator cuff more resulting in impingement.

Solutions for this problem generally start with limiting overhead activities and taking an anti-inflammatory for a few weeks. If this does not get results an evaluation by your physician may be warranted. Additional medical treatment and physical therapy may be recommended. In some cases surgery is needed if the injury to the rotator cuff is significant. Surgery is generally done arthroscopically through small poke hole type incisions as an outpatient. The surgery relieves the pressure on the rotator cuff and alleviates pain by removing the hook portion of the acromion. Arthroscopy patients can generally return to normal daily activities rapidly.