Shoulder arthritis

What it is

The ball at the top of the upper arm bone and the shallow socket on the shoulder blade are covered with smooth cartilage. In osteoarthritis that cartilage thins and wears away, the joint loses its smooth movement, and the bone responds by forming spurs around the edges. The joint becomes painful and stiff.

Most shoulder arthritis is osteoarthritis with no single cause. It can also follow an old fracture or repeated dislocations, a long-standing large rotator cuff tear, or an inflammatory condition such as rheumatoid arthritis. It is less common than arthritis of the hip or knee because the shoulder does not carry body weight.

You can compare a normal and an arthritic joint on the 3D shoulder model under "Arthritis".

Symptoms

• A deep ache in the shoulder, worse after use and in cold or damp weather.
• Pain at night, especially lying on that side.
• Stiffness. Turning the arm outwards and reaching behind the back are usually lost first.
• Grinding or clicking as the joint moves.

Symptoms fluctuate. Bad spells lasting weeks are often followed by better ones, so one bad month does not mean the joint has suddenly deteriorated.

How it is diagnosed

An X-ray shows it clearly. A CT or MRI scan is only needed if an operation is being planned, to assess the shape of the socket and the state of the rotator cuff tendons.

What you can do

Keep it moving

Regular gentle stretching preserves the movement you have, and strengthening the muscles around the shoulder helps it cope. Exercise is the core treatment recommended for osteoarthritis of any joint.¹ It will not wear the joint out faster. A physiotherapist can set a programme that suits a stiff shoulder.

Adapt

Keep things you use often between waist and shoulder height, use the other arm for reaching, and break up heavy jobs. Heat is soothing for many people.

Pain relief

Paracetamol and anti-inflammatory gels or tablets are used as needed, at the lowest dose that works. Anti-inflammatory tablets are not suitable for everyone, so check with your GP or pharmacist. Strong opioid painkillers are not recommended for arthritis: they work poorly for this kind of pain and cause problems of their own.¹

Injections

A steroid injection into the joint can settle a flare for a few weeks to a few months. It is helpful for getting through a bad spell or a particular event, and can be repeated occasionally. It does not alter the course of the arthritis. Injections of hyaluronic acid (a joint lubricant) are not recommended by the National Institute for Health and Care Excellence, because trials have not shown a worthwhile benefit.¹ See the guide to shoulder injections.

Keyhole surgery

Washing out or tidying an arthritic shoulder through the keyhole does not give lasting benefit and is not generally advised.

When to consider a replacement

There is no stage on an X-ray at which a replacement becomes necessary. The decision rests on how you are:

• pain that regularly disturbs sleep
• pain that is not controlled by the measures above
• loss of function that stops you doing things that matter to you

About nine in ten shoulder replacements are still in place ten years later.² The operation, its risks and the recovery are described in the guide to shoulder replacement.

Waiting does not usually make the operation less successful, so there is no need to have it before you are ready. The exception is a shoulder that is becoming very stiff or weak quickly, which should be reviewed.