Calcific tendinitis
Disorder characterized by calcium deposits in a tendon
From Wikipedia, the free encyclopedia
Calcific tendinitis is a common and expected aspect of tendinopathy or enthesopathy where deposits of calcium phosphate form in a tendon or enthesis.[1] Calcium in a tendon or enthesis is seen on radiographs (X-ray imaging).
| Calcific tendinitis | |
|---|---|
| Other names | calcified/calcareous tendinitis/tendinopathy, tendinosis calcarea, hydroxyapatite deposition disease, calcific periarthritis |
| |
| A plain X ray of the shoulder showing calcific tendinitis | |
| Specialty | Rheumatology  |
| Symptoms | Chronic shoulder pain during activities; acute shoulder pain |
| Duration | Self-limiting, typically resolves in 6-9 months |
| Risk factors | Diabetes, hypothyroidism |
| Diagnostic method | X-ray |
| Treatment | Physiotherapy, extracorporeal shockwave therapy, surgical excision |
| Medication | NSAIDs |
Calcification in soft tissues is associated with acute inflammation on uncommon occasions, a condition referred to as acute calcific tendinitis. It’s important to distinguish acute calcific tendinitis from the very common calcium deposits in tendinopathy and enthesopathy.
The symptoms of acute calcific tendinitis can mimic infection: intense pain, and warmth, redness and swelling in superficial sites. The symptoms from acute calcific tendinitis resolve spontaneously over a few weeks. The calcium is typically amorphous on radiographs in acute calcific tendinitis and often disappears after the inflammation resolves. Treatment with non-steroidal anti-inflammatory drugs can alleviate pain.
Calcifications in the rotator cuff were first described by Ernest Codman in 1934. The name, "calcifying tendinitis" was coined by Henry Plenk in 1952.
Signs and symptoms
Calcification is an integral part of tendinopathy.[1][2] In acute calcific tendinitis the calcium deposit is breaking down, and people experience severe acute pain.[2] Those affected tend to hold the shoulder rotated inwards to alleviate pain.[2] Some people experience heat and redness at the affected shoulder. Motion is very painful.[2]
Cause
The pathophysiology of tendinopathy is mucoid degeneration, part of which is chondroid metaplasia of the fibroblasts. Chondroid metaplasia means the fibroblasts are acting like cartilage cells (chondrocytes). Fibroblasts that are acting like chondrocytes can deposit calcium into the soft tissues as they do in bone. Calcification in the tendons is a common component of tendinopathy.
The calcification consists of calcium phosphate.[2] These deposits are common in rotator cuff tendinopathy and are most frequently found in the supraspinatus tendon (63% of the time), and less frequently in the infraspinatus tendon (7%), subacromial bursa (7%), subscapularis tendon (3%), or in both the supraspinatus and subscapularis tendons at the same time (20%).[2]
Diagnosis
Acute calcific tendinitis is typically diagnosed by physical examination and X-ray imaging.[2] When calcium deposits for in the setting of tendinopathy there is typically uniform density and a clear margin.[2] In the setting of acute calcific tendinitis, calcium deposits may appear cloudy and with unclear margins.[2] By arthroscopy, formative stage deposits appear crystalline and chalk-like, while resorptive stage deposits appear smooth resembling toothpaste.[2] Ultrasound is also used to locate and assess calcium deposits. In the formative stage, deposits are hyperechoic and arc-shaped; in the resorptive stage deposits are less echogenic and appear fragmented.[2][3]
Treatment
The first line of treatment for calcific tendinitis is typically nonsteroidal anti-inflammatory drugs to relieve pain, rest for the affected joint, and sometimes physical therapy to avoid joint stiffness.[3][2] For those with severe pain direct injections of steroids to the affected site are often effective for pain relief,[2] but may interfere with reabsorption of the calcium deposit.[3] For those whose pain doesn't improve with medication and rest, the deposit can be dissolved and removed with techniques called "ultrasound-guided needling", "barbotage", and "US-PICT" (for "ultrasound percutaneous injection in calcific tenditis"). In each, ultrasound is used to locate the deposit and guide a needle to the affected site. There saline and lidocaine are injected to dissolve the deposit, then removed to wash it away.[2][3][4] Another common treatment is extracorporeal shockwave therapy, where pulses of sound are used to break up the deposit and promote healing.[2] There is little standardization of energy levels, duration, and time interval of treatment; though most studies report positive outcomes with low- to medium-energy waves (below 0.28 mJ/mm2).[3]
Surgery
Surgery is only recommended once 6 months of conservative, non-operative treatment has failed to reduce symptoms. Surgery is arthroscopic and involves calcification removal with or without acromioplasty of the shoulder.[5] Additionally, debate remains over whether a complete removal of the deposits is necessary, or if equal pain relief can be obtained from a partial removal of calcium deposits.[6]
Removing the deposits either with open shoulder surgery or arthroscopic surgery are both difficult operations, but with high success rates (around 90%). About 10% require re-operation. If the deposit is large, then frequently the patient will require a rotator cuff repair to fix the defect left in the tendon when the deposit is removed or to reattach the tendon to the bone if the deposit was at the tendon insertion into the bone.
Outcomes
Epidemiology
Calcific tendinitis typically occurs in adults aged 30 to 50, and is rare in those older than 70. It is twice as common in women as men.[2]
Risk factors that increase the chance of developing calcific tendinitis include; hormonal disorders, like diabetes and hypothyroidism, autoimmune disorders, like rheumatoid arthritis, and metabolic disorders that also cause kidney stones, gallstones, and gout. Occupations that consist of repetitive overhead lifting, such as athletes or construction workers, do not seem to significantly increase the likelihood of developing calcific tendinitis.[6]
History
Calcifications in the rotator cuff tendon were first described by Ernest Codman in his 1934 book The Shoulder.[3] In 1952, in his study on x-ray therapy for people with such calcifications, Henry Plenk coined the term "calcifying tendinitis".[3][8]