Why Is Calcific Tendinitis So Painful?

There are a couple of shoulder conditions that can be extremely painful. One is adhesive capsulitis, better known as frozen shoulder, and the other is calcific tendinitis. Calcific tendinitis is characterised by the formation of calcium deposits in the rotator cuff tendons of the shoulder. A few months ago Hackett et al from the University of New South Wales published the results of a study that could explain why calcific tendinitis is so painful. Their findings are published in The Journal of Bone & Joint Surgery.

They concluded that there was “a significant increase in neovascularization and neoinnervation in calcific tendinitis lesions of the shoulder along with an eightfold increase in mast cells and macrophages. The findings are consistent with the hypothesis that, in calcific tendinitis, the calcific material is inducing a vigorous inflammatory response within the tendon with formation of new blood vessels and nerves”.