Transverse ulnar bone transport osteogenesis: a new technique for limb salvage for the treatment of distal radial osteosarcoma in dogs.

Objective: To develop instrumentation and a technique for transverse ulnar bone transport osteogenesis in dogs.

Study Design: Cadaveric study and in vivo validation (1 dog).

Sample Population: Paired cadaveric antebrachii (n=10 dogs) and 1 live dog.

Methods: Circular fixator constructs were applied and fitted with reeling or linear motors designed to transport an ulnar segment transversely into a defect created by excising the distal 50% of the ipsilateral radius. A longitudinal osteotomy of the adjacent ulna was created and the segment was transported across the radial defect. Pre- and post-distraction CT scans were used to compare the efficacy of each construct. The procedure was performed unilaterally in a live dog using the reeling motor (RM) construct.

Results: Both constructs effectively transported the ulnar segment into the defect. Subjectively, the RMs were easier to apply and operate. No significant differences were observed in the objective measures of efficacy between the 2 construct types. The live dog produced viable regenerate bone after transverse ulnar bone transport.

Conclusions: Transverse ulnar bone transport should be considered a potential method for limb salvage in dogs with osteosarcoma (OSA) of the distal radius. The RMs were effective and clinically applicable.

Clinical Relevance: Transverse ulnar bone transport osteogenesis affords the benefits of longitudinal radial bone transport osteogenesis, allowing resolution of large longitudinal radial defects in a substantially less time as a result of shortening the transport distance. This would be beneficial when treating conditions such as OSA where minimizing convalescence and maximizing quality of life is a priority.