This goal of this study was to clinically evaluate the potential of a novel hybrid imaging techniques, called x-ray guided multispectral diffuse optical tomography, for identifying physiological parameters of joint tissues that can be used to distinguish between osteoarthritic and healthy joints in the hand. Between 2006 and 2009, the distal interphalangeal (DIP) finger joints from 40 subjects including 22 osteoarthritis patients and 18 healthy controls were examined clinically and scanned by the hybrid imaging platform that integrated a C-arm based x-ray tomosynthetic system with a mutlispectral diffuse optical imaging system. Based on the reconstructed results from the 40 subjects, it was observed that oxygen saturation and water content were two statistically most significant physiological discriminators for differentiation of the healthy joints from the osteoarthritic ones. ©2010 Optical Society of America.