From a pool of 131 supracondylar fractures of the humerus in 131 patients who were treated conservatively, all of which healed in an average time of 4.5 weeks without complications related to the treatment itself, the cases of fifty-three patients were reviewed at maturity. The average age at follow-up was twenty-six years. Nine patients had unimportant limitation of elbow motion, and slight atrophy of the musculature of the arm or forearm, or of both, was present in six patients. Arm-length discrepancy was never observed. The carrying angle remained at about the same value that had been present at the time of fracture-healing in eighteen patients, decreased in twenty-two patients, and increased in thirteen. Malrotation of the distal fragment of the fracture only rarely caused medial tilting of the fragment with consequent cubitus varus. Varus deformity was present in four patients and valgus deformity, in three. None of the patients with valgus deformity had ulnar-nerve palsy. According to our results, varus and valgus deformities of the elbow after supracondylar fractures of the humerus seem to be caused either by growth imbalance of the growth plate of the distal end of the humerus (four patients) or by malreduction of the fracture (three patients). Twelve patients in the entire pool had neurological complications at the time of the fracture. Ten of those patients fully recovered from the deficit, whereas two--one with a radial-nerve deficit and the other with ulnar-nerve involvement--still had neurological impairment at follow-up.