Hand fractures (phalanges and metacarpals) are very common and they constitute a cause of considerable ambulatory and surgical departments workload. Isolated, undisplaced and displaced but stable fractures are usually treated non-operatively, and classical indication to surgery are unstable, oblique, spiral, intra-articular, open and complex fractures. Results of some studies suggest that oblique, spiral and apparently unstable fractures can be successfully treated conservatively, questioning afore-mentioned indications to surgeryThe aim of this prospective and randomized study was to compare the results of conservative versus operative (by fixation with K-wires) treatment of isolated, displaced and extra-articular metacarpal fractures.Material and methods. Forty-seven patients, 36 male (77%) and 11 female (23%) with a mean age of 34 years (range 16-75), with isolated metacarpal fractures, were randomly allocated to operative, by intramedullary fixation with K-wires (24 patients), or conservative, by reduction and immobilization (23 patients) treatment. Patients were followed-up at 2 and 6 months, and the assessments included measurements of active range of motion of fingers, total grip and pinch strengths, angular deformity on X-rays and subjective hand function with DASH questionnaire.Results. In one patient (4%) treated conservatively, an unacceptable secondary displacement occurred, and he was withdrawn from the study. and given surgical treatment. All fractures consolidated. At 2 months assessment, no statistically significant differences between the variables in the operative and conservative treatment groups were noted, except of the angular deformity on X-rays, which was significantly greater after conservative than operative treatment (median 31° vs 9°). At 6 months assessment, an active range of motion of involved fingers was statistically significantly greater in operative, than in conservative treatment group (median 269° vs 250°) and the angular deformity was significantly lesser after operative than conservative treatment (median 24° vs 12°). There were no statistically significant differences between the groups with regard other analysed parameters. None healing disturbances and malrotations were noted.Conclusions. The results of this study indicate the equal effectiveness of both the operative by K-wiring, and conservative treatment of fractures of the metacarpals. The better anatomical outcomes in terms of the degree of angular deformity did not translate directly into the better function of the hand.