The purpose of this study was to propose a reasonable guideline for using corticosteroids as a means of treating calcific tendinitis of the shoulder. We reviewed 73 patients who were treated with the administration of steroids into the subacromial bursa. Of these,34 regained near normal shoulder function within 3 weeks after the start of the treatment. The effect of 7 clinical and radiological items on the recovery time was analysed using the quantification theory of Hayashi. It was found that the symptomatic period before treatment and the location of the calcium deposit significantly affected the recovery time. Categories working for early recovery were a symptomatic period of less than 3 weeks and a calcium deposit in tendons other than the supraspinatus. Thus, the use of corticosteroids should be limited to patients with a shorter history and to those without calcium in the supraspinatus tendon.
