Anatomic Shoulder Replacement
Shoulder Joint Replacement is a surgery that replaces the worn joint surfaces of an arthritic shoulder joint. “Anatomic” refers to the replacement of the worn shoulder joint ball and socket of the joint with artificial components that simulate the anatomy of a normal shoulder, hence the term “Anatomic”. The ball is replaced with a stainless steel ball. A titanium stem fixes the prosthesis in the upper arm bone or humerus. The socket is replaced with a hard wearing plastic lining. This eliminates the bone to bone contact that was causing pain in the arthritic shoulder joint. Releasing the tight tissue around the joint will help to restore better joint mobility.
Indications for Anatomic Shoulder Replacement?
Anatomic shoulder Joint Replacement is particularly suited to patients with arthritic wear of the shoulder but a sound rotator cuff. The rotator cuff tendons have an important role in centralising the artificial ball within the plastic lining of the socket. Healthy rotator cuff tendons will also contribute to better shoulder function.
There are some circumstances where anatomic shoulder replacement may not be the best option. Anatomic Shoulder Replacement relies on the rotator cuff tendons to keep the artificial ball centred in the joint socket. The rotator cuff may be torn and possibly not repairable. The tendons might be intact but of poor quality. They may gradually tear away, sometimes many years after the joint replacement. These scenarios can allow the metal ball to start riding upwards relative to the plastic lining. This can lead to premature wear or loosening of the plastic glenoid component. There may also be deterioration in the function of the joint replacement if the tendons fail. Consideration will be given to the use of a Reverse Shoulder Replacement in these circumstances.
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 may need to be reshaped to provide a stable foundation for the plastic lining. The plastic component is fixed to the bone by multiple pegs on its underside that are secured to the bone by bone cement. The marrow canal of the humerus is shaped to allow the insertion of a titanium stem. The stainless steel ball is then fitted to the metal stem. The new ball can then be positioned in the plastic socket and tissues around the shoulder joint are repaired. 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