Category Archives: Andrew Mahoney

The shoulder joint is the most movable and complex joint in the body, therefore the opportunity for complex problems is greater. A few of the more common shoulder conditions are arthritis and rotator cuff injuries.  When both of these conditions are present, it can present a complex problem for the orthopedic surgeon. A relatively new FDA-approved procedure may be the answer:  reverse total shoulder replacement.

A brief review of shoulder anatomy

The shoulder joint is made up of three main bones; the collarbone (clavicle), the shoulder blade (scapula), and the upper arm bone (humerus). The shoulder joint is a ball-and-socket-type joint. The “socket” is a shallow dish-shaped area of the scapula. The top of the humerus bone is round like a ball, and fits into the socket.  The bones are held in place by the rotator cuff, which is made of four major muscles, tendons, and ligaments. The ligaments from the rotator cuff attach directly to the head of the humerus bone and hold the arm in place.

The shoulder joint is the most movable and complex joint in the body, therefore the opportunity for complex problems is greater. A few of the more common shoulder conditions are arthritis and rotator cuff injuries.  When both of these conditions are present, it can present a complex problem for the orthopedic surgeon. A relatively new FDA-approved procedure may be the answer:  reverse total shoulder replacement.

A brief review of shoulder anatomy

The shoulder joint is made up of three main bones; the collarbone (clavicle), the shoulder blade (scapula), and the upper arm bone (humerus). The shoulder joint is a ball-and-socket-type joint. The “socket” is a shallow dish-shaped area of the scapula. The top of the humerus bone is round like a ball, and fits into the socket.  The bones are held in place by the rotator cuff, which is made of four major muscles, tendons, and ligaments. The ligaments from the rotator cuff attach directly to the head of the humerus bone and hold the arm in place.

Rotator Cuff Tear and Arthritis

The shoulder can be injured easily at work, around the house, or during sports or exercise activities. When the cause of shoulder pain is related to your rotator cuff, the simple act of throwing a ball to your grandchild may cause enough pain to drop you to your knees.  In many cases minor rotator cuff injuries can be rehabilitated without surgery, but major damage must be surgically repaired.  In some cases, it may not be possible to fully restore the strength and stability of a damaged rotator cuff.

When your pain is caused by degeneration of soft tissues and the effects of arthritis inside the joint, you can thank the natural aging process. While Mild to moderate arthritis can be managed conservatively with medication, physical therapy, and therapeutic injections; severe arthritis can only be resolved by replacing the joint.

Traditional Vs Reverse Shoulder Replacement

In a traditional shoulder replacement, the ball of the humerus is replaced by a half ball, and the socket is replaced by a “cup”.  This mimics the same anatomy as the original bones, minus the arthritis.  If necessary, the rotator cuff is repaired and reattached to the new joint.  A traditional shoulder replacement is best for patients when the rotator cuff is intact or is repairable.

In a reverse shoulder replacement, the cup is placed on the top of the humerus – replacing the ball – and the ball is placed in the cup – replacing the socket.  See figure below. Reversing the ball and cup placement puts the deltoid muscle in place as the major muscle for the new joint instead of the rotator cuff. A reverse shoulder replacement is also recommended for people with severe arthritis and rotator cuff damage, or prior failed traditional shoulder replacement.  The reverse shoulder replacement procedure was approved by the FDA in 2004.

Am I a Candidate?

Through a comprehensive evaluation by your doctor which can include X-rays, and MRI, the doctors will determine which type of shoulder replacement is best suited for your case.  The extent of damage in your shoulder joint will determine the type of surgery you need.  People with unrepairable damage to their rotator cuff along with severe arthritis are the best candidates for reverse shoulder replacement.

It all starts with a visit to Tucson Orthopaedic Institute, Southern Arizona’s largest and most advanced multi-specialty orthopedic group.  Here, we are able to diagnose your symptoms to determine the best course of action for you. We can perform either a traditional or reverse shoulder surgery, and arrange your physical therapy so you can get back to doing all you like to do.

Several of our orthopedic surgeons are trained and experienced in both traditional and reverse shoulder replacement: Dr. Kevin Bowers and Dr. Christopher Stevens in the Oro Valley office, Dr. Joel Goode and Dr. Andrew Mahoney in the East office, and Dr. Steven Shapiro in the Northwest office.  Call one of our conveniently located offices today to schedule an appointment at Tucson orthopaedic Institute.