Calcific tendinitis is a common condition where deposits of calcium phosphate form in a tendon, sometimes causing pain at the affected site.

The disease often resolves completely on its own, but is typically treated with non-steroidal anti-inflammatory drugs to relieve pain, rest and physical therapy to promote healing, and in some cases various procedures to breakdown and/or remove the calcium deposits.

[1] In the "resorptive phase" when the calcium deposit is breaking down, many experience severe acute pain that worsens at night.

[2] Finally, in the "postcalcific stage" the calcium deposits are replaced with new tissue and the tendon completely heals.

[1] During the formative phase, X-ray images typically reveal calcium deposits with uniform density and a clear margin.

[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").

[1][3][2] Another common treatment is extracorporeal shockwave therapy, where pulses of sound are used to break up the deposit and promote healing.

[1] 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).

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.

[3] In 1952, in his study on x-ray therapy for people with such calcifications, Henry Plenk coined the term "calcifying tendinitis".