REVERSE SHOULDER REPLACEMENT
Reverse Shoulder Replacement provides a solution for problems that were previously untreatable in the shoulder. It is a highly technical operation which is best performed by a surgeon with expertise in this form of shoulder replacement.
In the normal shoulder, the rotator cuff muscles help balance the ball of the arm bone (humeral head) in the socket against the upward pull of the deltoid muscle. In large rotator cuff tears, the rotator cuff tendons that normally are interposed between the humeral head and the overlying coracoacromial arch become progressively thinned until the humeral head moves upwards and rubs against the bone of the arch.
A conventional shoulder replacement device mimics the normal anatomy of the shoulder: a plastic "cup" is fitted into the shoulder socket (glenoid), and a metal "ball" is attached to the top of the upper arm bone (humerus). In a reverse total shoulder replacement, the socket and metal ball are switched. The metal ball is fixed to the socket and the plastic cup is fixed to the upper end of the humerus.
A reverse total shoulder replacement works better for people with large rotator cuff tears because it relies on different muscles to move the arm. In a healthy shoulder, the rotator cuff muscles help position and power the arm during movement. A conventional replacement device relies on the rotator cuff muscles to function properly. In a patient with a large rotator cuff tear and cuff tear arthropathy, these muscles no longer function. The reverse total shoulder replacement relies on the deltoid muscle, instead of the rotator cuff, to power and position the arm.
CANDIDATES FOR SURGERY
Reverse total shoulder replacement may be recommended if you have:
• A completely torn rotator cuff that cannot be repaired
• Arthritis with a rotator cuff tear
• A previous shoulder replacement that was unsuccessful
• Fracture of the shoulder
SURGERY
Reverse total shoulder replacement is a highly technical procedure. Reverse shoulder replacement is usually a very successful operation and most patients are very happy with the result. As with any operation, there are risks associated with undergoing surgery. The risks of having any operation such as bleeding, nerve damage, clots in your legs or lungs, heart attacks or a reaction to the anaesthetic could occur but are usually very uncommon occurring in less than 1%. There is a risk with shoulder replacement that the shoulder could dislocate or come out of joint after surgery. There is a risk that infection could occur either in the wound or deep in the joint. With dislocation or deep joint infection, you are likely to require further surgery to address the issue. The rate of either of these complications is around 1%. Over time the shoulder replacement can loosen from the bone and may need revision surgery. Revision surgery may also be required if the polyethylene joint wears away with time due to the use of the replacement.
PREPARATION FOR SURGERY
Individuals should optimize their health so that they will be in the best possible condition for this procedure. Smoking should be stopped a month before surgery and not resumed for at least three months afterwards. Any heart, lung, kidney, bladder, tooth or gum problems should be managed before surgery. Any infection may be a reason to delay the operation. The area of the skin incision must be clean and free from sores and scratches. Individuals should also recognize that reverse shoulder replacement cannot restore normal function to the severely damaged shoulder.
The individual needs to plan on carefully protecting the arm for three to six weeks after the procedure. Driving shopping and performing usual work or chores may be difficult after surgery. Plans for necessary assistance need to be made before surgery. For individuals who live alone or those without readily available help arrangements for home help should be made well in advance.
RECOVERY
After surgery, you will have several doses of antibiotics to prevent infection, and pain medication to keep you comfortable. Most patients have a nerve block to help with pain management. Most patients are able to eat solid food and get out of bed the day of surgery. You will most likely be able to go home on the second or third day after surgery.
The shoulder will be protected in a sling for three to six weeks after surgery. During this time you will be able to temporarily remove the sling for meals, showering, exercises and small amounts of writing or computer work. The wound needs to be kept dry until it is healed and the dressing removed at the clinic appointment two to three weeks after surgery.
LONG-TERM OUTCOMES
After rehabilitation, you will most likely be able to lift your arm to just above shoulder height and bend your elbow to reach the top of your head or into a cupboard. Some people have difficulties getting their arm behind their back after surgery. Reverse total shoulder replacement provides excellent pain relief and patient satisfaction is typically very high.