Shoulder Replacement Surgery
Indications
Painful arthritis of the shoulder glenohumeral joint, not amenable to lesser treatments of activity modification, simple medication, or arthroscopic debridement.
Goals of Surgery
Pain relief and often improvement in movement and function.
The level of movement and functional improvement varies depending on the condition of the shoulder including the rotator cuff.
Often patients with primary glenohumeral osteoarthritis achieve good pain relief and two-thirds normal range of movement or better.
Planning
Pre-operative medical assessment may be advised to optimise safety for anaesthesia and recovery support.
Pre-operative imaging includes X-Rays and often CT or MRI scans. These may assist in planning the procedure.
Arthroplasty Options
Total Shoulder Replacement (ball and socket replacement)
Reverse Shoulder Arthroplasty (“ball” is on the socket side, designed to compensate for deficient rotator cuff muscles and tendons)
Hemiarthroplasty (replacing the ball but not the socket)
The decision on which type of implant is used is based on a number of individual factors including the pattern of bone wear and the condition of the rotator cuff
How Long Do They Last?
In New Zealand, more than 90% of shoulder replacements have not had a revision procedure in the first 10 years from surgery.
In Hospital
The procedure is done under general anaesthetic through an incision on the front of the shoulder.
The operation often takes 2 hours or longer.
Expectations
The goal is for the shoulder to feel around 80% right around 4 – 6 months from surgery, and 90% right or better 9 – 12 months from surgery.
Sometimes it can take a long time for all aching to fully resolve.
A shoulder sling is applied at the end of the procedure.
There are routine X-Rays and blood tests done on the first post-operative day.
On the second day, usually the patient can be helped to shower in a light sling and start the pendulum exercise. This is the most gentle shoulder exercise, involving leaning forward, letting the arm hang down and swinging the arm in a gentle circle, for around 30 seconds twice a day.
The hospital stay is often 3 or 4 nights, depending on the level of independence and home support.
The First 6 Weeks
The sling is worn for the first 6 weeks.
Sometimes we recommend physiotherapy – passive external rotation to neutral, and passive elevation exercises, starting around 2 weeks from surgery.
You should not drive in this time as your arm is in a sling.
Depending on pre-surgery level of function, you may need help with shower and dressing, cooking and cleaning.
After the First 6 Weeks
Wean off using the sling over 2 or 3 days.
Use the arm gently in comfort range.
Don’t lift heavier than 1 – 2 kg.
Do gentle range of motion exercises but don’t force it.
Be careful not to stress the healing subscapularis muscle, so don’t force external rotation or internally rotate forcefully.
Work on posture and scapular control.
3 Months Post Surgery
Sometimes some physiotherapy guided light inner range strengthening.
However, the shoulder should never be used for heavily lifting or rapid ballistic activities, or stretched forcefully.
Risks
The risks and complications of shoulder replacement surgery include, but are not limited to: anaesthetic and medical risks, infection, fracture, neurovascular injury, instability, pain, loosening and wear.