Evaluating bone fracture healing utilizing Doppler Imaging Modes, Shear Wave Elastography, X-Ray and Dual-Energy X-Ray Absorptiometry in a rabbit model

The healing of bone fracture is a complex, multistage process consisting of inflammation in the local tissue, angiogenesis, callus formation, and eventually, remodeling and restoration of the bone to its original morphology. This study investigated methods of evaluating bone fracture healing process using Doppler flow imaging, cSMI, mSMI, and SWE, relative to X-ray, DXA and CD-31 stains in a rabbit model. The standard of care evaluation is based solely on the callus formation although is well known the inflammation and angiogenesis play an important part in the process. The vascular evaluation provided by the use of Doppler imaging modes can help with predicting patients at risk for delayed healing or non-unions in the future. The comparison of SWE with X-ray and DXA was done in order to provide a radiation free alternative to the evaluation of the callus formation. The results comparing Doppler modes with CD-31 stains showed that cSMI on day 21 was comparable with the standard of care (p = 0.13). The results comparing SWE with DXA showed that it was comparable with the standard of care (p > 0.14). These results indicate that there may be potential in using ultrasound imaging to monitor the bone fracture healing process.