Small rotator cuff tears (RCTs) can become large tears over time. The four shoulder muscles of the rotator cuff hold the head of the humerus in the shoulder socket. Without this active stabilization, the humeral head moves upward. It starts to rub against the bottom of the acromion. The acromion is the bone that comes from the scapula (shoulder blade) across the top of the shoulder.
The end result is a condition called rotator cuff arthropathy. There is weakness of the rotator cuff, increased wear and tear on the shoulder, and upward migration of the humeral head. In this article, orthopedic surgeons from the University of Southern California review rotator cuff tear arthropathy.
They begin by presenting a summary of the anatomy and biomechanics of the rotator cuff. Results of recent studies explaining RCTs are presented. It appears that there are many factors that can cause RCTs.
Some patients are born with slight anatomical variations that put pressure on the rotator cuff. Age and repetitive use combined together cause wear and tear. Over time, the patient develops painful symptoms, weakness, and decreased shoulder joint motion.
Several theories are offered to explain what actually happens inside the joint with RCT arthropathy. But none of these theories help explain why some people with massive RCTs never develop RCT arthropathy.
Once the exam and X-rays help make the diagnosis, treatment can begin. There is no consensus yet what is the best approach to manage this problem. Conservative care is advised at first. This consists of antiinflammatory drugs and physical therapy.
If nonoperative care fails to relieve symptoms or restore motion, then surgery may be needed. Shoulder replacement is the most common operation. Hemiarthroplasty and reverse ball-and-socket arthroplasty are the two procedures of choice. A hemiarthroplasty just replaces one side of the joint. This is usually the round head with a stem into the upper shaft of the humerus.
Reverse shoulder replacement is a fairly new concept. Instead of a round ball at the end of the humerus that fits into the socket of the scapula (shoulder blade), there is a socket at the end of the humerus. On the other side, a round metal ball is inserted where the shoulder socket normally occurs. The two components still form a ball-and-socket joint but the parts are switched.
The reverse shoulder replacement is gaining in popularity. Patients get pain relief and increased motion. Often, the hemiarthroplasty relieves the pain. But it does nothing to restore normal shoulder motion. Long-term results of this treatment for RCT arthroplasty remain unknown.