Objective: The objective of the submitted paper is to demonstrate the results of sports fractures of the diaphysis of the humerus and possible complications. Method: During a five-year period 18 men were followed up and treated during hospitalization with a spiral fracture of the diaphysis of the humerus. Their average age was 31.3 years. The mechanism of injury was in all rotational. In ten instances a fracture contracted during a „levered“ fight was involved, in the remaining eight patients the cause of fracture was a fall from a bicycle or occurred during skiing. Five patients were not operated because the position of the fragments was favourable.In the remaining patients osteosynthesis was performed. An intramedullary nail was used in 7 and osteosynthesis by means of a splint in 6. The function of the shoulder joint and elbow was evaluated and compared with the sound side, as well as the muscular strength and subjective feeling of the patients Results: In all conservatively treated cases the fracture healed. The original function of the extremity was fully restored. In operated patients three times a pseudoarthrosis developed which was treated by surgical revision and four times injuries of the radial nerve. The subsequent rehabilitation was however quicker and in all instances complete function was achieved. Conclusions: The majority of spiral fractures of the humerus heals after conservative treatment. Early functional treatment is essential for preserving the function of the affected extremity. Surgical treatment should be indicated carefully and the radial nerve should be carefully protected.

        Key words: humeral shaft – spiral fractures – arm wrestling