This is a multicenter, randomized superiority trial comparing closed reduction and cast immobilization to flexible intramedullary nails in 7-12 year old children with > 10° of angulation and/or > 10mm of shortening in displaced both bone forearm shaft fractures (AO-pediatric classification: 22D/2.1-5.2). A total of 78 patients with minimum 2 years of expected growth left are randomized in 1:1 ratio to either treatment group. The study has a parallel non-randomized patient preference arm. Both treatments are performed under general anesthesia. In the cast group a long arm cast is applied for 6 weeks. The flexible intramedullary nail group is immobilized in a collar and cuff sling for 4 weeks. Data is collected at baseline and at each follow-up until 1 year.~Primary outcome is 1) PROMIS Pediatric Item Bank v2.0 - Upper Extremity and 2) forearm pronation-supination range of motion at one-year follow-up. Secondary outcomes are Quick DASH, Pediatric pain questionnaire, Cosmetic VAS, wrist range of motion as well as any complications (malunion, delayed union, non-union or deep wound infection, peripheral nerve injury, need for re-intervention during 1-year follow-up) and costs of treatment.~The investigators hypothesize that flexible intramedullary nailing results in a superior outcome.
The forearm is the most common fracture location in children, with an increasing incidence. Displaced forearm shaft fractures have traditionally been treated with closed reduction and cast immobilization. Diaphyseal fractures in children have poor remodeling capacity, and malunion can thus cause permanent cosmetic and functional disability. Internal fixation especially with flexible intramedullary nails has gained increasing popularity, without evidence of a better outcome compared to closed reduction and cast immobilization.