YAN LU, MD , BRETT NEMKE, BS, DOUGLAS M. LORANG, PhD , ROEL TRIP, MD , HIROHITO KOBAYASHI, MS, and MARK D. MARKEL, DVM, PhD, Diplomate ACVS Veterinary Surgery June 2009 38 4 467 - 476 Objectives—To compare bone healing of tibial osteotomy repaired with Nitinol wire braid and hardened steel rods (Braid system) and polymethylmethacrylate bone cement with an interlocking intramedullary (IM) nail fixation in an ovine model. Study Design—In vitro and in vivo experimental study. Animals—Adult female sheep (n=22). Methods—Using sheep tibia, a middiaphyseal transverse osteotomy was performed in the right tibia, which were then randomly assigned to the Braid system group or IM nail group (n=5). The left tibia were used as controls. The torsional properties of tibial constructs were compared. The study was repeated in vivo in 12 sheep and mechanical properties and bone healing were evaluated at 12 weeks. Results—In vitro, there was no significant difference in torsional stiffness between the groups. In vivo, operative time for the Braid system group was significantly shorter than the IM nail group. At 12 weeks, there were no significant differences in maximum torque and torsional stiffness between IM nail and Braid system groups nor were there significant radiographic or histologic differences between the groups. Conclusions—The Braid system might decrease operative time for repair of transverse middiaphyseal tibial fractures and result in similar bone healing at 12 weeks after surgery compared with an interlocking IM nail repair. Clinical Relevance—A Nitinol Braid system may be a treatment option for transverse midshaft tibial fractures.