Clinical use of recombinant human bone morphogenic protein-2 in a whooping crane (Grus americana)

Objective - To report use of recombinant human bone morphogenetic protein-2 (rhBMP-2) as adjunctive therapy for treatment of a comminuted, open, proximal humeral fracture in an avian species. Study Design - Clinical report. Animals - A 3.5-month-old male whooping crane (Grus americana). Methods - An open, severely comminuted humeral facture was stabilized with an intramuscular (IM) pin/type IA external skeletal fixator with tie-in configuration. rhBMP-2 was applied in a calcium phosphate matrix (CPM) paste directly to the fracture site as a bone graft substitute. Radiographic evidence of bone healing was monitored for 14 weeks. Results - Substantial bony callus was evident at 4 weeks and at 8 weeks there was bridging callus with obvious bony remodeling. The fixation was destabilized at 9 weeks by IM pin removal, bone healing progressed and the fixator was removed at 11 weeks. By 14 weeks both cortices had been re-established with continued callus remodeling evident. Conclusion - rhBMP-2, applied in a CPM paste, was used as a bone graft substitute in the treatment of a comminuted, open humeral fracture in a whooping crane. Clinical Relevance - Use of rhBMP-2/CPM should be considered in treatment of avian fractures.