Calcific tendonitis is a condition that causes the formation of a small sized calcium deposit within any tendon in the body. The most common place are the tendons of the rotator cuff. These deposits are usually found in individuals at least 30-40 years old. The calcium deposits are not always painful, and even when painful they will often spontaneously resolve after a period of one to four weeks. It is linked to many other conditions, such as Adhesive Capsulitis and Subacromial Impingement.
What causes it?
The cause of calcium deposits within the rotator cuff tendon (calcific tendonitis) is not entirely understood. Different ideas have been suggested, including blood supply and ageing of the tendon, but the evidence to support these conclusions is not clear. One of the most compelling arguments is delayed healing.
Usually the tendon heals through the action of collagen forming cells (fibroblasts). After a period of weeks or months, the fibroblasts become less numerous in the region and are replaced by osteoblasts (bone forming cells). The osteoblasts, in turn stimulate the growth of bone (calcium) in the tendon. Hence the main reason for the development of calcific tendonitis appears to be delayed healing.
Calcific Tendinitis typical course
- Pre-calcification Stage: individuals usually do not have any symptoms in this stage. At this point in time, the site where the calcifications tend to develop undergo cellular changes that predispose the tissues to developing calcium deposits.
- Calcific Stage: during this stage, the calcium is excreted from cells and then coalesces into calcium deposits. When seen, the calcium looks chalky, it is not a solid piece of bone. Once the calcification has formed, a so-called resting phase begins, this is not a painful period and may last a varied length of time. After the resting phase, a resorptive phase begins–this is the most painful phase of calcific tendonitis. During this resorptive phase, the calcium deposit looks something like toothpaste.
- Postcalcific Stage: this is usually a painless stage as the calcium deposit disappears and is replaced by more normal appearing rotator cuff tendon.
As Calcific Tendinitis is directly linked to Frozen Shoulder and Adhesive Capsulitis, symptoms can be the same as those conditions:
- pain on movement
- stiffness and lack of movement
- painful swelling around the joint
- can present bulging tendons due to crystal deposits