Calcific tendonitis

What is calcific tendonitis?

Calcific tendonitis is a painful condition caused by a build-up of calcium deposits within a tendon, most often one of the tendons in your rotator cuff, the group of tendons that support your shoulder. The tissue surrounding the deposit can also become inflamed, adding to the pain.

Symptoms of calcific tendonitis

• Sudden shoulder pain, often without any injury to explain it
• Pain over the top or front of the shoulder, sometimes spreading down the upper arm
• Pain that's worse when lifting your arm away from your body or overhead
• Severe pain that disrupts your sleep, especially lying on the affected side
• Reduced range of movement in the shoulder, and sometimes some weakness
• Popping, clicking or grinding sensations when you move your shoulder

Not everyone with calcium deposits has symptoms. Around 1 in 5 people have deposits that are picked up incidentally on a scan taken for another reason, without ever causing any pain.

Causes of calcific tendonitis and who's at risk

The exact cause isn't fully understood, though it's thought to be linked to natural wear and tear within the tendon as it ages, rather than to any particular activity or sport. It's also:

• more likely to develop in adults between the ages of 30 and 60
• slightly more common in women than in men
• linked to endocrine conditions such as diabetes and an underactive thyroid
• more common in people who have other calcium-related conditions, such as kidney stones or gallstones
• possibly linked to gout, though this isn't fully proven.

It usually affects one shoulder, most often the supraspinatus tendon, though both shoulders are affected at the same time in around 1 in 10 people.

Are there different stages of calcific tendonitis?

Rather than distinct types, calcific tendonitis tends to move through overlapping stages, which helps explain why the pain can vary so much over time:

1. Formative stage: The calcium deposit gradually forms and grows. This stage often causes little or no pain, so it's frequently discovered by chance
2. Resorptive stage: Your body starts to reabsorb the deposit. This is usually when pain is at its most intense, since the process itself is inflammatory, and pain often comes on suddenly and can wake you at night
3. Post-calcific stage: The deposit is replaced by healthy tissue, and your range of movement gradually improves.

How is calcific tendonitis diagnosed?

Your GP or physiotherapist will examine your shoulder and ask about your symptoms, but a clinical examination alone can't reliably confirm calcific tendonitis, since it shares symptoms with other shoulder problems such as impingement, frozen shoulder, rotator cuff tears, and arthritis of the joints around the shoulder.

An X-ray usually confirms the diagnosis by showing the calcium deposit directly, and also helps rule out other causes of shoulder pain. An ultrasound scan can also detect deposits and is often used to guide certain treatments. An MRI scan isn't routinely needed, but may be used if the picture is unclear or to check for a co-existing rotator cuff tear.

As mentioned, calcific tendonitis is sometimes confused with frozen shoulder, since both cause significant pain, particularly at night, and restricted movement. Calcific tendonitis tends to come on more suddenly, while frozen shoulder develops more gradually and tends to affect a slightly older age group.

How is calcific tendonitis treated?

Most people improve with non-surgical treatment, and surgery is only needed in a small proportion of cases.

Non-surgical treatment

• Rest: And avoiding movements that aggravate the pain
• Over-the-counter or prescribed painkillers: Such as ibuprofen or naproxen
• Physiotherapy: Including stretching and strengthening exercises
• Steroid injections around the tendon: This can settle inflammation and ease pain, but it can be short-lived if the deposit is still present
• Extracorporeal shockwave therapy (ESWT): This uses a probe on the skin to send shockwaves that help break down the deposit so your body can reabsorb it, usually given as a short outpatient course
• Barbotage: This is an ultrasound-guided procedure where a needle is used to break up and draw out the calcium deposit under local anaesthetic, often followed by a steroid injection to settle any remaining inflammation.

Taken together, non-surgical treatment succeeds for the majority of people, though reported success rates vary quite widely between studies, and can be lower if you also have an underlying condition such as diabetes.

Surgical treatment

Surgery is generally only considered if symptoms haven't settled after around 6 months of non-surgical treatment, or continue to significantly affect your daily life.

It's usually done as keyhole (arthroscopic) surgery under general anaesthetic, to locate and remove the deposit. Depending on what's found, this may be combined with widening the space around the tendon or repairing a rotator cuff tear at the same time.

Surgical outcomes are generally good, with some studies reporting successful results in around 9 in 10 people. Many people feel considerably better within 6 weeks, and most within 3 months, though it can take longer to settle completely, and mild twinges of pain can occasionally continue for up to 2 years afterwards. You'll usually need to wear a sling for a few weeks to protect your shoulder while it heals.

Complications from any of these treatments are uncommon. With injections or barbotage, there's a small risk of infection. With surgery, risks are low but can include infection, a period of stiffness that usually eases with time, and rarely, nerve injury.

When should I see a doctor?

See your GP or physiotherapist if you have sudden or intense shoulder pain, stiffness, or pain that's disrupting your sleep. It's also worth getting checked before pushing through any strenuous activity on a painful shoulder, since prompt diagnosis and treatment gives you the best chance of a quick recovery.