Reverse Shoulder Replacement
Shoulder Joint Replacement is a surgery that replaces the worn joint surfaces of an arthritic shoulder joint. “Reverse” refers to the replacement of the worn shoulder joint ball with a hard wearing plastic cup or socket. The bony socket of the joint is resurfaced with a stainless steel dome. Thus the socket becomes a ball. The point of reversing the ball and socket is that this configuration can compensate for the problems that might be caused by a torn or deteriorating rotator cuff. A torn or failing rotator cuff will allow the ball component of the more conventional Anatomic Shoulder Replacement to ride upwards in the socket. This can result in premature wear or loosening of the plastic socket component of an Anatomic Shoulder Replacement.
The design of a Reverse Shoulder Replacement helps to keep the two prosthetic components to in their correct orientation regardless of the state of the rotator cuff. This stable fulcrum allows the deltoid muscle to help to elevate the arm overhead despite the lack of intact rotator cuff tendons.
Indications for Reverse Shoulder Replacement?
Reverse Shoulder Joint Replacement is particularly suited to patients with arthritic wear of the shoulder as well as tearing or degeneration of the rotator cuff tendons. Reverse Shoulder Replacement helps to address the potential problem of gradual rotator cuff failure after Anatomic Shoulder Replacement.
Sometimes the gradual failure of the rotator cuff tendons can be the underlying cause of the joint becoming arthritic. Healthy rotator cuff tendons have an important role in keep the head of the humerus centred in the shoulder joint socket. If the rotator cuff tear becomes extensive enough the head will start to ride upwards with attempts to elevate the arm overhead. Instead of the ball rolling smoothly in the socket it will begin to slide upwards causing wearing of the joint cartilage. This culminates in a condition referred to as Rotator Cuff Tear Arthropathy. Reverse Shoulder Replacement is particularly suited to treating this condition.
Fractures of the upper humerus may be so fragmented as to require replacement of the shoulder joint. This type of fracture is often associated injury to the rotator cuff tendons. Reverse Shoulder Replacement may be helpful in this setting.
Shoulder Joint Replacement Procedure
The surgery is performed under general anaesthesia. It takes approximately 2 hours to complete. The surgery is performed through an incision at the front of the shoulder. The worn head of humerus is removed. The socket of the joint is reshaped. A central hole is drilled in the socket. A titanium plate that covers the surface of the socket is fitted. It has a metal post on its under-side that is driven in to the bone. It is secured by screws that lock the plate to the bone. A stainless steel dome is fitted to the plate thus converting the socket to a ball shape. The marrow canal of the humerus is then shaped to allow the insertion of a titanium stem. A metal backed plastic cup is fitted to the stem. Thus the s original ball has now been replaced by a cup or socket. The new joint components are engaged to provide a stable joint with smooth pain free movement. The tissues around the shoulder joint are repaired to enhance stability. A dressing is applied to the surgical wound.
Postoperative Care for Shoulder Joint Replacement
Although there will be some pain after the surgery, many patients notice from the outset that it a different pain to the arthritic pain they were experiencing. Stroger pain medication will be required in the first few days after surgery. This can be gradually reduced in strength and frequency as the shoulder becomes more comfortable.
The Physiotherapist will help you to start exploring gentle use of your shoulder while in hospital.You will generally be in hospital for about 4 to 5 days following a shoulder joint replacement. Unlike a hip or knee joint replacement you do not usually require admission to a rehabilitation hospital after shoulder replacement. Some older patients who are on their own at home may want to consider a brief period of respite as a stepping stone to home. Spending the first week or so after surgery with family is also an option for some. You can usually go direct to home with the physio having given you a series of rehabilitation exercises to work on at home.
It is expected that by the time you leave hospital you will be able to dress and shower without assistance. You will be able to get the dressing wet briefly in the shower and pat it dry. Although Mr Lyons will ask you to wear a sling when outdoors or travelling in a car you can take the arm out of the sling at home to perform light waist level tasks. You will for instance to use a fork or spoon, a computer keyboard etc. Exploring gentle tasks such as these is part of your rehab. You should not drive until discussed with Mr Lyons.
You will have a post-surgery appointment with Mr Lyons approximately 2 weeks after surgery. Stitches will be removed at that visit. You will be encouraged to spend more time out of the sling and gradually increase use of the shoulder as any soreness allows. It is expected that you will be able to lift the arm to chest or shoulder height after about 6 to 8 weeks. The bulk of improvements occur within about 3 to 4 months from the time of surgery. However some patients notice gains in shoulder strength and mobility for as long as 12 months after surgery. If you are having trouble regaining enough strength and mobility Mr Lyons may advise some supervised Physiotherapy or Hydrotherapy at the appropriate time.
You will have further appointments to monitor your progress until such time as the best possible outcome has been achieved.
Complications of Shoulder Joint Replacement
As with any major surgery, there may be potential risks. It is Mr Lyons’ brief to have precautions in place to minimise risk and avoid complications. Risks to bear in mind include:
- General Medical Conditions (Heart, Lung, Blood Pressure, Diabetes, Blood Clots etc.)
- Anaesthetic Complications
- Nerve, Blood Vessel, Bone Injury
- Shoulder Instability
- Wearing or Loosening of Artificial Components