We report the results of hydraulic distension of the glenohumeral joint with manipulation using local anaesthesia and radiographic control in 24 frozen shoulders in 22 patients. In a prospective study, the pre- and postoperative range of movement in 3 planes was measured by an electronic digital inclinometer. At 3 months, the range compared with the unaffected shoulder was abduction 93%, glenohumeral abduction 84%, forward flexion 94%, backward extension 96%, internal rotation 75% and external rotation 73%. The procedure was repeated once in 3 patients. One also had a manipulation under general anaesthesia and was classed as a failure. The subjective outcome was good in all the other patients. This investigation shows that the technique is safe, reliable and effective treatment for frozen shoulder.