From 1970 to 1980 155 supracondylar fractures of the humerus in children were treated conservatively by the method of Blount and 33 were treated surgically. The indications for operation were flexion-fractures, second- or third-grade compound fractures, vessel or nerve lesions and for easier nursing of polytraumatized patients. Out of 82 fractures treated by collar and cuff 64 (78%) show an ideal, 12 (15%) a good and 6 (7%) a satisfactory result two to ten years after the accident. In 18 cases one could see a defective varus function of more than five degrees.