The spine is a complex mechanical structure, understanding the mechanics of this structure is critical in developing new interventions to combat cancer and other diseases. The purpose of the study was to use image registration to measure strain allowing quantification the biomechanical response of vertebrae under axial compression. A rigorous validation for using image registration to measure strain in bone was presented, strain was accurately measured up to -0.2 with a detection limit of 0.001. Strain fields in was a rodent vertebrae were measured by image registration and compared to finite element analysis, which showed limited agreement. In a pilot study differences in the biomechanical responses of tumour involved and control thoracolumbar rat vertebrae were assed with image registration. The average axial strain in the tumour-bearing vertebrae group was 0.025 greater. Image registration was applied successfully to was WAS measure strain in whole bones in 3D, demonstrating the efficacy for assessing pathologies and treatments.