Calcific tendinitis is a self limiting condition due to deposition of calcium hydroxyapatite within tendons, usually of the rotator cuff.
Typically this condition affects middle aged patients between the ages of 30 and 60, with a slight predilection for women 2.
The condition passes through four stages 2:
- fibrocartilaginous metaplasia (see below)
- calcific or formative
- symptoms are variable from none to pain on movement
- most symptomatic
- pain due to extravasation of calcium hydroxyapatite into adjacent tissues, especially subacromial bursa
- pain typically lasts 2 weeks
- variable symptomatology
- some restriction of movement common
- may last months
Calcific tendonitis results from the deposition of calcium hydroxyapatite within the substance of a tendon, and is thought to be due to decreased oxygen tension, leading to fibrocartilagenous metaplasia and secondary mineralization 1.
This condition most frequently affects the rotator cuff of the shoulder 1.
- supraspinatus - 80%
- infraspinatus - 15%
- subscapularis - 5%
- periarticular soft tissues in addition to tendons
- calcific deposits are usually visualized as homogeneous hyperdensity with variable morphology, but typically globular / amorphous with poor margins.
- hypointense homogeneous signal
- adjacent tendon may be thickened
- some enhancement surrounding deposit may be seen
- hypointense calcium deposits
- hyperintense signal may be present peripherally due to edema
- hyperintense subacromial-subdeltoid bursal fluid
- T2*: calcifications may bloom
Treatment and prognosis
Controversial and difficult to measure due to the inherent variability of the symptoms and the self limiting nature of the disease. Potential treatments include 2:
- oral analgesia / anti-inflammatory medication
- subacromial local anesthetic / steroid injection
- aspiration of mineralized material
- ultrasound therapy
In the shoulder consider
- incidental calcification: seen in 2.5-20% of 'normal' healthy shoulders 1-2
- degenerative calcification
- seen in previously torn tendons
- generally smaller
- slightly older individuals
- loose bodies
- associated chondral defect
- associated secondary osteoarthritis