For centuries, practitioners of Traditional Chinese Medicine (TCM) have depended on changes in tongue appearance to aid in disease pattern recognition and TCM diagnosis. The purpose of this study was to systematically examine photographs of dog tongues with known Bony Bi syndrome (i.e. musculoskeletal disease) and compare them to tongue pictures of dogs with no historical or clinical evidence of Bony Bi. Tongue Spirit (robustness and vitality), cracks and color were the three parameters assessed. The tongues of 99 client-owned dogs were photographed while spontaneously panting. Fifty dogs had Bony Bi syndrome and 49 were considered non-Bony Bi controls. Dogs with Bony Bi were significantly more likely to have tongues with poor Spirit (i.e. shriveled and limp) than dogs without Bony Bi (p<0.0001). A Chi-Square test found cracks to be significantly different between dogs with and without Bony Bi syndrome (p=0.0020). Further analyses showed diffuse cracks were strongly correlated with the absence of Spirit, and that while both Spirit and cracks are correlated with Bony Bi, Spirit was a stronger predictor than cracking. Tongue color was compared and no differences were found between those that had Bony Bi and those that had no known Bony Bi. The challenges of comparing tongue color visually without computerized models are discussed. Computer models for human tongue analysis may be able to be applied to animals in future studies for more accurate analysis. To our knowledge, this is the first, systematic, English-language study of TCVM tongue diagnosis in dogs.