Factors affecting outcome after pediatric forearm fracture include fracture angulation and fracture position. A new index, axis deviation, combines these factors. Two review studies were performed to determine if axis deviation correlated with outcome. In the first study, 35 subjects were reviewed 2.7 years after fracture without radiographs. In the second study, 152 fractures were reviewed a mean of 4 years after fracture, with 124 patients consenting to undergo radiographs. In both studies, the new index, axis deviation, correlated better with restricted forearm movement than either degree of angulation or fracture position. Midshaft and distal remodeling occurred and could be predicted in terms of axis deviation. We propose that an axis deviation of < 5 at the time of union be the reduction criteria of pediatric forearm-shaft fracture regardless of fracture position.