The Use of Triphasic Bone Graft for the Treatment of Pediatric Bone Cysts: Experience at 2 Institutions.

Unicameral/aneurysmal bone cysts can lead to pain, fracture, and limb deformity. In this study, the authors evaluated the outcome of triphasic bone graft to treat unicameral/aneurysmal bone cysts. They retrospectively evaluated 41 immature patients from a prospectively enrolled cohort from 2 institutions treated from May 9, 2007, to November 1, 2014. Medical record review and evaluation of radiographs and computed tomography scans were performed. The authors characterized replacement of the material by normal bone or recurrent cyst at final follow-up. They recorded rates of fractures and complications after treatment. Twenty-nine patients were treated in Wisconsin, and 12 patients were treated in Florida. Average follow-up was 2.8 years. At follow-up, 13 of 41 patients had cyst recurrence. Three patients had fracture after initial treatment; 2 were treated surgically. Two of 9 patients with extraosseous bone graft had soft tissue swelling, and 1 required debridement. Complications did not differ by cyst type, location, sex, age, or use of internal fixation. For 27 patients with at least 2-year follow-up, percent fill of triphasic bone graft at initial surgery correlated with rate of recurrence at final follow-up: 15 of 27 patients with no cyst recurrence at final follow-up had a mean of 100% initial fill, and 12 of 27 with cyst recurrence at final follow-up had a mean of 90% initial fill (P=.048). Using triphasic bone graft for the treatment of unicameral/aneurysmal bone cysts, the authors observed a 7% rate of clinical recurrence (3 of 41 had fracture). Because this material has the potential to be locally inflammatory, efforts are needed to keep it within the bone.