Sandwich Allograft for Repair of Tibial Nonunion Fracture in Patient with Osteogenesis Imperfecta Secondary to Failure of Alternative Interventions

Background - Osteogenesis Imperfecta (OI) is a group of connective tissue disorders caused by mutations in the type I collagen gene. Type I collagen acts as a mechanical scaffold for various tissues of the body, the most notable being bone. Patients with this disease classically present with fracture of long bones. These fractures are especially difficult to treat, as the bone quality limits the ability to adequately stabilize the site and it takes longer for bone to heal. As a result, nonunion of these fractures is a common phenomenon. Case Information - A 36-year-old female presents with past medical history of OI and known tibial fracture. After failure of conservative management and previous surgical interventions including tibial osteotomy with open reduction internal fixation and subsequent revision surgery for hardware displacement to correct the tibial fracture, the patient elected for surgical correction of the deformity. Repair was performed using a "sandwich allograft" technique, with added cancellous bone chips and Bone Morphologic Protein 2 (BMP2) impregnated collagenous matrix to facilitate bone regeneration. Conclusion - Patients with Osteogenesis Imperfecta frequently suffer from nonunion fractures. As an adult, these fractures are commonly complex and have prolonged healing processes. The "sandwich allograft" technique presents an additional surgical method which can be used for patient with failure of traditional surgical methods. Repair of these fractures results in reduction of deformity, decrease incidence of future complications, restoration of function though the ability to weight bear or ambulate, and ultimately result in better quality of life.