Calcific periarthritis

Calcific periarthritis (perry-arth-ritus) is a condition that can cause painful swelling around your joints. 'Peri' means that the swelling is around the joint, not inside the joint itself.

Calcium crystals occur naturally in the body and help make our bones and teeth strong. However, some people have too many calcium crystals in other parts of the body – for example:

• in a tendon, one of the strong cords that attach our muscles to our bones – this is referred to as calcific tendonitis
• in a bursa, a fluid-filled sac that acts like a cushion which allows muscles, tendons and ligaments to glide smoothly over our bones as we move.

It’s possible to have crystals in a tendon and not know that they’re there, as they might not cause any pain or other problems.

But sometimes the crystals can leave the tendon, or ‘shed’, into the soft tissue surrounding the joint. When this happens the hard, sharp crystals can cause pain and swelling as they rub against the soft tissues. This is known as calcific periarthritis.

This condition most commonly affects tendons that help the shoulders move, but it can also affect the hips, hands and other parts of the body.

Calcific periarthritis causes pain and swelling around a joint, and the joint may be tender to the touch. These symptoms usually come on quite quickly, which is referred to as 'acute', and can be severe.

In most cases the pain and swelling only occurs when the crystals leave the tendon and go into the soft tissues in the surrounding area.

However, if you have crystals in a tendon around the shoulder, this can cause problems even if they haven’t shed into the soft tissues. A large crystal, in particular, can be painful and make it difficult to move your arm properly.

Typical attacks of acute calcific periarthritis gradually settle on their own, without causing any damage to the tendon or surrounding tissues.

Even without treatment, the pain and swelling usually start to ease after the first few days and most people find they're getting back to normal within about four weeks.

Once shedding starts, the crystals usually continue to shed until they've all gone. The crystals don't usually re-form in the same place, so it's often a one-off problem in that particular part of the body.

However, if you have an attack of calcific periarthritis in one shoulder then you may be more likely to get it in the other shoulder. And some people go on to have attacks in other parts of the body too.

As you get older, natural chemical changes in the body can make it more likely that calcium crystals will form in blood, urine or soft tissues.

The following conditions can also cause you to have too much calcium in your body:

• an overactive parathyroid gland (hyperparathyroidism)
• kidneys that aren’t functioning properly
• diabetes – a condition that causes high levels of glucose, a type of sugar, in the body.

It's not always clear why crystals start to shed, but it quite often happens a day or two after an injury or over-use.

There are several tests that can help make a diagnosis of calcific periarthritis.

X-rays or ultrasound scans can show any calcium crystals forming in a tendon.

Blood tests can check for:

• inflammation in the body
• calcium levels
• possible other causes of symptoms, such as an infection
• problems with the kidneys, which in rare cases can be a cause of calcific periarthritis.

Calcific periarthritis usually settles on its own without any treatment. However, because it can be very painful and distressing, you may need treatment to relieve pain and reduce inflammation.

Aspiration and injection

Sometimes there may be swelling in a bursa, a fluid-filled sac that provides cushioning to your joints. In this case, your doctor may use a needle and syringe to remove extra fluid from the bursa. This is called aspiration, and it can quickly reduce pain.

Your doctor will numb the area first, so it isn't too painful. Usually, once the fluid has been drawn out, your doctor will inject a small amount of a long-acting steroid treatment into the bursa through the same needle. This helps to reduce swelling in the lining of the bursa and prevent the build-up of more fluid.

Applying ice

Applying an ice pack around the painful area is a quick and safe way of taking the edge off pain. You can buy ice packs, or you could use a pack of frozen peas or ice cubes wrapped up in a damp towel, to protect your skin.

Drugs

Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, may reduce the swelling and ease the pain.

As with any drug, there are some risks and side effects with NSAIDs, so check with your doctor or a pharmacist if they're suitable for you.

Are there any treatments to prevent the crystals forming?

There are no drug treatments that can prevent the formation of calcium crystals in tendons.

If you have a condition that may increase the likelihood of calcific periarthritis, such as kidney disease or an overactive parathyroid gland, then these should be treated.

Are there any treatments to remove the crystals?

If necessary, there are procedures to remove crystals, especially if they are large deposits.

Surgery

Key-hole (or endoscopic) surgery may be used to remove a large deposit that is restricting movement and causing discomfort.

As with any surgery, there are some risks of complications, such as infection. If you’re considering surgery, it’s important to discuss this with your doctor.

Shock-wave treatment

A procedure called shock-wave treatment may be an option to remove large calcium deposits from a tendon if they're causing problems. This is most commonly done for calcium deposits in a tendon in the shoulder.

High-frequency shock waves are sent to the affected area. The vibrations can help to break up large deposits of crystals and allow the smaller particles to be slowly dissolved away.

People normally have several sessions of shock-wave treatment spaced about a week apart. Each session only takes about five minutes. You may experience some discomfort during the treatment. You'll be given  an NSAID tablet to reduce swelling and an anaesthetic patch to help numb the area. But let your healthcare professional know if you need them to reduce the intensity of the treatment.

This procedure causes the calcium deposits to shed from the tendon, which is sometimes necessary but can itself can cause pain and swelling. Therefore, you may have some tenderness and bruising afterwards.

People normally have several sessions spaced about a week apart.

There are some possible complications from shock-wave treatment, such as the risk of damage to the tendon. Therefore, if you’re considering this procedure it’s important to discuss it fully with your doctor.

Exercise

It’s important that you get the joint and muscles in the affected region moving as soon as possible. It will help the healing and prevent the joint from becoming stiff.

Doing a small amount of exercise on a regular basis will help the inflamed tissues return to normal. A physiotherapist can help you with expert advice.

Diet and nutrition

The formation of calcium crystals isn’t usually affected by your diet. For general health and well-being, however, you should eat a well-balanced diet and avoid becoming overweight.

It’s not possible to get calcific tendonitis or calcific periarthritis by eating too much calcium. It’s important to have calcium in your diet, because it can reduce the chances of osteoporosis, a condition which causes bones to become thin and to fracture.

Find out more about eating well with arthritis and related conditions.