Effect of low modulus titanium plate fixation on rabbit femur bone healing

The effect of a low-rigidity titanium alloy plate on bone formation during the early stage of fracture healing was investigated in this work. An artificial defect was created on rabbit femurs, and fixations of Ti–6Al–4V ELI (Ti-64) and Ti–29Nb–13Ta–4.6Zr (TNTZ) implant plates were attached to the defect with two screws at both ends of the implant plate. After 3 weeks, the rabbits were euthanized, and cross-sections of the femurs were evaluated by scanning electron microscopy, image analysis, hematoxylin–eosin staining, and Vickers hardness tests. Both fixations showed similar patterns of new bone formation in the defect area but differences in average callus area. The use of the TNTZ implant plate led to a smaller area (8.316 mm 2 ) and harder (20 HV) callus when compared with the results of the Ti-64 implant plate (area: 18.394 mm 2 ; callus hardness: 13 HV). We conclude that low-rigidity titanium alloys could improve bone formation during the early stages of fracture healing. Graphical abstract