Arthritis of the hand

What is it?

Arthritis is wear and tear of the joint. The information here deals mainly with arthritis of the finger (knuckle) joints. Arthritis of the thumb and arthritis of the wrist are covered individually. There are two main types of arthritis that can affect the finger joints.

Osteoarthritis is a slow process that develops over many years. With this type of arthritis the joint cartilage gradually roughens and becomes thin. The bone underneath thickens and the bone at the edge grows outwards causing bony spurs (osteophytes).  The joint may swell as the body makes extra fluid to lubricate the joint. The joint may get deformed and there will be gradual loss of movement.

Inflammatory arthritis includes conditions like rheumatoid disease or psoriasis.

What is its cause?

The most common cause of osteoarthritis is wear and tear of the joint due to ageing. This is called ‘primary osteoarthritis’. Sometimes a major injury (fracture, dislocation) to a joint may lead to osteoarthritis in later life and this is termed as ‘secondary osteoarthritis’. Arthritis in the joints of the finger is most common. The end joints of the fingers (DIP joints) are most commonly affected.
In rheumatoid arthritis the arthritis spreads throughout the body. In this condition the patient’s own immune system mistakenly attacks the joints causing damage to many joints in the body.

What are the symptoms and how is the condition diagnosed?

The symptoms of primary osteoarthritis start in middle age. They are of gradually increasing pain and stiffness. This is followed by difficulty in straightening or bending the finger. Firm to hard swellings may form over the end knuckles due to the underlying spurs (see picture above). These are called Heberden’s nodes. They can be unsightly and sometimes painful. Cysts may form over the end knuckle joint. These are known as mucus or myxoid cysts. The cysts can become inflamed, painful and may intermittently discharge. With time the symptoms may worsen and cause functional disability. Functional disability will depend on which knuckle joint is affected.

The fingers can be damaged by rheumatoid or psoriatic arthritis at any age. With rheumatoid disease there may be other problems due to synovitis (inflammation of the soft tissue lining over the tendons), tendon ruptures, or joint instability and deformity.

Will further tests or investigations be needed?

An x-ray of the hand is needed (as below). It will confirm the extent and type of arthritis. X-rays will show lost joint space with bony spurs (osteophytes), cysts and bony sclerosis.

What is the treatment?

1. Initial conservative management consists of painkillers, anti-inflammatory medication and activity modification. It is aimed at easing the pain and regaining further range of motion.
2. A steroid injection in the affected joint may relieve symptoms. The injection very occasionally causes some thinning or colour change of the skin at the site. Improvement is variable and can be temporary.
3. If the above measures fail, then surgery is advised. There are various operations that can be considered. The type of surgery that will be recommended will depend on the nature and longevity of the symptoms, extent of arthritis, the knuckle joint affected, age and functional demands of the patient.

The main operations are:

Excision of Heberdon’s nodes or mucus / myxoid cysts: If the nodes or cysts are painful, excision is recommended. The procedure is practised under local anaesthesia as a day case. After the operation a sticky dressing is applied over the surgical wound. A bulky supportive cotton-wool dressing then goes on top of that. This supportive dressing is reduced after a couple of days. The small sticky dressing should be left for 10 -12 days, after which time the stitches will need to come out. The arm should be kept elevated after surgery for 1-2 days as this will prevent the fingers from swelling and causing discomfort. Light use of the hand should be possible from the day of surgery. Active movements of the finger are recommended soon after surgery.

Fusion of the affected joints (DIP or PIP joint): If the end or middle knuckle joints continue to be painful, fusion of the joints is considered. A successful operation will get rid of the pain, movement of the joint will however be lost. This is the surgery of choice for painful end-joint finger arthritis. Fusion is also usually considered for middle-knuckle arthritis though replacement of that joint is an alternative (see x-ray below). Fusion will be achieved by using plates, screws or wires.

Joint replacement surgery (PIP or CMC joint): In the last decade there has been a significant progress in joint replacement surgery. Painful arthritic first knuckle joints are best treated by joint replacement (see x-ray above). Medium to long-term results are encouraging, and movement of that joint is maintained. The joints are made out of pyrocarbon which is the same material used to make artificial heart valves. Middle knuckle joints can also be replaced (as in the picture below) but joint replacements cannot be performed if the ligaments are damaged and the joint is unstable.

Surgery for the rheumatoid hand: In rheumatoid patients there are significant deformities. A combination of staged procedures that include deformity correction, joint fusion and silastic flexible joint replacements will need to be considered.