Cause of Calcific TendonitisThe cause of calcium deposits within the rotator cuff tendon is not entirely understood. Different ideas have been suggested, including blood supply and aging of the tendon, but the evidence to support these conclusions is not clear.
Calcific tendonitis usually progresses predictably, and almost always resolves eventually without surgery. The typical course is:
- Precalcification Stage
Patients 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.