To evaluate whether Extracorporeal Shock Wave Therapy (ESWT) is an effective treatment without side effects for chronically painful calcifying tendinitis.

Study subjects were 72 patients (17 males and 55 females) aged 37-64 years, with a mean of 48, showing chronic, symptomatic, calcifying tendinitis of the shoulder refractory to other conventional conservative therapies. Calcifications were type I or type II according to the classification of Gartner, and with a minimum diameter of 10 mm. Patients with type 3 calcific tendinitis were excluded, because this type has a strong tendency to spontaneous resolution. Extracorporeal shock wave therapy comprised one or two treatments, each consisting of 800 shocks, with a frequency of 120 impulse per minute and the energy density of 0.14 mJ/mm². We assessed the presence and size of calcified deposits at 1, 3, 6 and 12 months by conventional radiography. All patients also underwent clinical examination, and the Constant (and Murley) score and pain were calculated. The intensity of pain was measured with the visual analogue scale (VAS) from 0 to 10 points, where 0 represents the absence of pain and 10 unbearable pain.

One month after the treatment, complete resorption of the calcium deposits was observed in 19 patients (26%), partial resorption was observed in 26 patients (36%), and no modification in the calcium deposits was observed in 27 patients (38%). At six months the complete disappearance of the calcium deposits was noted in 42 patients (68%), but in the 10 patients (14%), calcium deposit appeared unchanged. This result is remained unvaried after 6 month follow-up. Using the Constant and Murley score, this study showed a significant decrease in pain and a significant increase in shoulder function (p<0.001). At six months, 76% of the patients presented satisfactory functional result. About 15% reported a subjective and objective recovery, and only 6 patients (8%), classified as poor result but in our series no differences were found between results at 6 month and 12 month follow-up. At 12 month follow-up there were differences in the Constant score between treated shoulder and contralateral side, respectively 77.6 (59-91) and 87.2 (74-96), but not significant. There were no side effects.

ESWT is an effective treatment without side effects and an alternative therapy for chronically painful calcifying tendinitis of the shoulder refractory to conventional therapies.