Abstract: Objective To reproduce a rat model of anterior ankle impingement syndrome by treadmill exercise or/and impacted device, and to evaluate the model by different methods. Method Fourty SD rats were randomly divided into 4 groups: blank control group, exercise group, impact group, exercise & impact group. The rats in the exercise group were received treadmill exercise 5 days per week for 4 weeks according to the following schedule: 12 m/min for 30 minutes every day, slope grade of the treadmill was adjusted at 30° impact group were impacted by self-made special device which gave energy of 4.5 J in the impacted area, 300 times per day; exercise & impact group were received both treadmill exercise and impact, and the parameters were the same as above. During the experiment of the 10,20 and 30 days,the flexion and extension of ankle joint pain score, ankle joint volume were detected, the Micro CT and pathological observation were applied to evaluate the model at 30 days. Result The flexion and extension of ankle joint pain score, ankle joint volume in exercise & impact group were significant difference compared with the single induced groups, most data of the Micro CT test and the auricular cartilage pathological stage in exercise & impact group were mild or moderate injury, which was significant difference compared with the single induced groups. Conclusion Treadmill exercise combined with impacted device can reproduce an ideal rat model of anterior ankle impingement syndrome, which similar to early stage or middle stage of osteoarthritis.

Key words: Anterior ankle impingement syndrome, Rats, Model, Evaluation