The Intra-articular Injection of a New Chitosan Biomaterial Prevents the Progression of Osteoarthritis in Aclt Rabbit Model

stained by Fast Green and Safranin-O, and assessed by OARSI recommendation for histological scoring of OA in mice. Results: IAI-HA groups showed similar gait patterns to that of sham group, while saline injected group showed gait disturbance at 12 and 16 weeks after the DMM surgery. In saline group, stand phase and single stance phase were statistically shorter, and swing phase was statistically longer than IAI-HA groups. There were no statistical differences in gait parameters between 800-HA group and 6000-HA group. Histological changes were similar among 800-HA, 6000-HA and saline group, demonstrating OA progression throughout all three evaluating time points. IAI groups showed higher histological score, suggesting more cartilage degradation than sham group, but there seemed to be no differences between each IAI group. Conclusions: Histological evaluation showed that OA has progressed at the time point of 8 weeks after the DMM surgery even in IAI-HA groups, but gait disturbance was started to be detected 12 weeks after the surgery only in saline groups. This result suggests that symptomatic changes develop after histological changes and it also support the effect of pain relief by IAI-HA. CatWalk could be of use to objectively quantify gait disturbance in DMM model and could be a useful tool for assessing the effect of other interventions against rodent OA models.