BACKGROUND: This study compared the incidence of loss of reduction (LOR) between metacarpal fractures fixed with screws alone and those fixed with plates and screws. Secondary aims included identifying patient or fracture characteristics associated with increased risk of LOR. METHODS: We retrospectively reviewed 138 metacarpal fractures in 106 patients treated with open reduction internal fixation with screws (60 fractures) or plates and screws (78 fractures) with a mean radiographic follow-up of 50 days for evidence of LOR. We compared the incidence of LOR between the screw and plate groups using a χ(2) test. We performed logistic regression analysis to determine whether patient age, sex, metacarpal location (index, long, ring, small), the presence of multiple metacarpal fractures, or fracture pattern were associated with increased incidence of LOR. RESULTS: Loss of reduction occurred in 19 (13.8%) of 138 fractures, with no statistically significant difference between lag screw (7 of 60, 11.6%) and plate fixation (12 of 78, 15.4%). Neither fracture pattern nor the presence of multiple metacarpal fractures was associated with an increased incidence of LOR, but patients experienced a 7% increase in the risk of LOR for each additional year of age. Loss of reduction occurred most frequently in index metacarpal fractures (4 of 12, 33%), although this did not reach statistical significance. CONCLUSIONS: We found no difference in LOR incidence between lag screw fixation and plate fixation. The overall incidence of LOR was higher in this study than previously reported and increased with increasing patient age.