Morton’s neuroma
X-ray showing degenerative osteoarthritic changes of the shoulder joint

Definition

Osteoarthritis or arthritis of the shoulder is a degenerative condition caused by chronic inflammation of the shoulder joints, the acromioclavicular and/or the gleno-humeral
joint, which leads to severe pain and loss of function.

Erosion of the shoulder joint cartilage due to arthritisPathology

Pathology


Osteoarthritis is a complex pathology of the joints originating from a variety of aetiologies, which have in common a persistent inflammatory process affecting multiple joint structures such as the cartilage, the connective tissue forming the synovium, the bursa and even tendons and muscles. Due to the protracted inflammation the surrounding tissues gradually degenerate and the joint space is reduced causing the opposing bones to rubbing against each other. These effects produce joint swelling, severe pain and decrease in joint mobility. 

Osteoarthritis may involve a single joint or several joints of the body and can arise suddenly or develop over years. This pathology is most frequent in women and ageing individuals.


After the age of 50 most people will have a degree of joint osteoarthritis. Sadly there is no treatment to cure this disease. Due to its heterogeneity, osteoarthritis of the shoulder is divided into six main pathologies:

1. Osteoarthritis

2. Rheumatoid arthritis

3. Post-traumatic arthritis

4. Rotator cuff tear arthropathy

5. Avascular necrosis

6. Overuse

Medical examination of the shoulder

Diagnosis

Diagnosis is formed by firstly discussing the patient’s medical history of previous shoulder injuries and then with physical examination including special tests to determine changes in the range of movement of the shoulder and pain that may arise with function. During clinical examination the following parameters are assessed:

Inspection of the shoulder to detect structural changes to muscles, tendons and ligaments

Pain triggered in response to palpation and pressure onto the shoulder

Range of movement during passive and active motion

Production of any noises with shoulder movement

Weakness of shoulder muscle

Contribution of other joints in case of rheumatoid
arthritis, gout

Primarily X-ray but also CT scan and MRI are useful diagnostic tools to detect changes in the shoulder such as joint restriction, cartilage degeneration, presence of bone spurs and associated injuries of the shoulder. These radiologic images allow to identify the nature of shoulder osteoarthritis. The diagnosis is also proven when the pain disappears after local injection of anaesthetics. If rheumatoid arthritis is suspected a blood test will confirm the disease. In case of gout or possible joint infection a small sample is aspirated from the synovium.

Prolonged symptoms of a trochanteric bursitis are treated with steroid injection into the bursa

Nonoperative treatment

Management of trochanteric bursitis begins with conservative treatment, which is mostly successful although with a lengthy prognosis. This approach involves:

Anti-inflammatory therapy with NSADs

Local injection of steroids

Local injection of platelet-rich plasma (PRP)

Reduction of physical activity and extreme sport

Physiotherapy

Surgical treatment

Top left: Shoulder arthroscopy for debridement of an acromion spur; Top right: Shoulder hemi-arthroplasty; Low left: Total shoulder replacement; Low right: Reverse total shoulder replacement

If conservative treatment for shoulder osteoarthritis is unsuccessful and the degeneration of the joint is advanced, surgery is the only option. This can be achieved via minimally invasive arthroscopic or open access surgery. Different techniques are available to repair the arthritic shoulder and vary relative to the disease conditions, use of the shoulder and age.

Arthroscopic resection arthroplasty is used to debride (remove) fragments on the inner joint to create more space and restore mobility. This procedure however will not eliminate arthritis but alleviate the symptoms temporarily. In most cases it is done arthroscopically. When the degenerative process has destroyed either the humeral head or the glenoid a prosthetic shoulder replacement is necessary.

This type of surgery requires open approach and comprises a partial or total shoulder prosthesis whereby:

Humeral head resurfacing is a simplified approach of joint reconstruction. The goal of this surgery is to resect part of the humeral head, which is covered using a metal cap. This treatment is a good compromise prior to proceed with hemi or total shoulder replacement and is specifically advised in younger patients practicing sport.

Hemiarthoplasy consists in the replacement of the entire humeral head with a metal sphere and a stem inserted in the humeral shaft.

Total shoulder arthroplasty involves a complete prosthetic replacement of both the humeral head as described in hemiarthroplasty and the glenoid (socket) of the shoulder, which is substituted with a concave plastic prosthesis.

Reverse total shoulderarthroplast is similar to the replacement of the socket and glenoid but employs a reversed ball-socket prostheses. The bio-mechanical concept is reversed and the glenoid becomes the ‘humerus head’ whereas the previous humerus head becomes the ‘glenoid’.

Resection arthroplasty is a procedure used for the treatment of arthritis of the acromio-clavicular joint. A section of the clavicle adjacent to the humeral head is resected and eventually replaced with scar tissue.

In the surgeries described a number of post-operative complications include: infections, bleeding, blood clot formation, damage of vessels and nerves, ongoing pain issues, reduced mobility and in very severe cases, ankylosis (stiffening) of
the shoulder joint. Loosening and dislocation of the prosthesis may occur especially early after surgery. This may require surgery if recurrent.