A treatment gap exists for moderately displaced pediatric distal forearm fractures (DFF), which carry a potential risk of improper reduction when treated conservatively. Currently, no standard method for the correction of the initial reduction of pediatric DFF is available. A novel closed reduction method has been proposed to correct and maintain a successful reduction throughout the healing process. This study further develops this novel cast system and evaluates its mechanical behavior through the design, construction, and testing of a biomechanical CAD model and pediatric forearm phantom. Initial results support the novel system as an improved treatment for pediatric fractures. Both the CAD model and tissue phantom indicate the ability of the system to manipulate a 15° fracture, with 0-1° of residual angulation.