Angus Keogh Procedures – Shoulder Arthritis / Replacement
Shoulder Arthritis / Replacement
Shoulder arthritis is a degeneration of the soft cartilage lining of the shoulder joint (glenohumeral joint). It can come about as a consequence of trauma, dislocations, infection or most commonly idiopathic. Idiopathic means that we don't really have a good explanation for the arthritis other than perhaps some genetic factors (familial toughness of the cartilage).
Shoulder arthritis is characterised by a progressive loss of range of movement in the joint and increasing aching pain in the joint.
Treatment in the first instance consists of simple measures such as anti-inflammatory medications, gentle movement therapy and hydrotherapy, hot packs, avoiding movements that cause pain and occasional injections into the joint with steroid medication.
When these simple measures fail then surgery can be considered.
Surgical techniques involve a joint replacement - removal of the arthritic joint surfaces (these are usually denuded of cartilage and there is bone grinding against bone). Once the joint surfaces are removed they need to be replaced with something. This is done with metal and plastic. Metal "stems” are used to anchor the components in the bone and a plastic articulating surface is placed between the two metal components, allowing smooth movement.
There are two types of joint replacement. The first is an “anatomical” replacement, replacing the bone components like for like (i.e. the head is replaced with a head, and the cup is replaced with a cup). This is the normal anatomical relationship, hence the use of the term “anatomical”. The mechanics of anatomical replacements demand that the normal tendon structures around the shoulder are intact to be able to control the anatomical replacement.
A newer development (over the last fifteen years) is the reverse shoulder replacement. The “reverse” involves replacing the ball part of the shoulder with a cup, and the cup with a ball. Hence the mechanics of the joint are reversed. It has been found that this arrangement improves outcomes of shoulder replacements where the normal tendon structures of the shoulder are deficient (i.e. rotator cuff tears).
Outcomes after shoulder replacement usually involve good pain relief but patients will have some stiffness. In my experience shoulder replacement outcomes can range from shoulder abduction (lifting the arm away from the body) from 80 degrees (roughly shoulder height) all the way to near normal range of motion. I usually tell people to expect range of movement to shoulder height only but it may turn out to be better than this.
Overall, this is a very pleasing operation as the majority of patients experience excellent pain relief although range of movement is rarely restored to normal.