Fractures of the apophysis of the olecranon occur in children with osteogenesis imperfecta. This report includes a cohort of 17 fractures in ten children who had osteogenesis imperfecta. Fourteen of the 17 fractures occurred after relatively trivial trauma. The mean age of the patients was 10 years. Interestingly, seven children sustained bilateral injuries. Five of the ten children were not known to have osteogenesis imperfecta prior to their elbow injury. Treatment consisted of either closed management or surgical fixation. Four minimally displaced fractures were treated with long-arm cast immobilization. One displaced within the cast and required surgical intervention. The majority of fractures were treated by open reduction and internal fixation through a posterior incision. The most common fixation technique was a tension band fixation. Sixteen of the 17 fractures were followed for more than 1 year. No patient reported pain or limitation of function. Mild irregularities were noted on the x-ray, but none appeared to have functional impact. One patient did develop an elbow contracture.
Fractures of the olecranon apophysis appear to result from avulsion forces secondary to the triceps. The relationship of this type of fracture to osteogenesis imperfecta is unknown. The most important take-home points from this article are that bilateral fractures can occur in up to 70% of children and that the olecranon apophysis fracture may be the presenting sign in children with undiagnosed osteogenesis imperfecta.
J Pediatric Orthopaedics