The Influence Of Active Recover To Healing Overuse Injury Of Rabbit’s Bone Tendon Junction

The overuse injury is very common in athletes. The long term intensive training lead the bone tendon junction in a condition which is excessive tractive, and lead to injury. However, the treatment of this injury is very difficult. It has a strong impact on the training and competition for athletes. Many athletes didn’t have active rest and treatment after injury, and continue the training with injury. Instead, the performance was decline. Therefore, the research is aimed at choosing rest or training, and how to training after bone tendon junction injury. It has guiding significance for athletes with injury to make training plan.Subjects and methods:The subjects are29New Zealand white female rabbits (18weeks, weight2.6±0.2kg), they were randomly divided into4groups, training after injury group (LL, n=8), rest after injury group(LR, n=8), injury control group (LC, n=8), blank control group(CON, n=4). The left and right side of the hind legs all are controlled in CON group. The left hind legs were took cyclic loading training in LL, LR and LC group, and the intensity of electrical stimulation is30%(7.06+0.71N) of the max contractility of quadriceps femoris in hind legs of rabbits in first four weeks,2hours each time,3times a week. On this basis, LR group took rest for4weeks, and LL group took training for4weeks in the intensity under injury (40%of the max contractility,2.82±0.28N). The animals were executed and taking material in the time of4weeks for LC group, and in the time of8weeks for LR, LL and CON group. The material were took decalcification, dehydration, paraffin embedding, sectioning and staining process, and observed the histological changes of bone tendon junction.Results and analyses:H&E staining showed that the cell count of LC group was significantly higher than CON group, LR group was significantly lower than LC group, there are no difference between the rest group. In fibrocartilage zone thickness, LC, LR and LL group all were significantly higher than CON group, LR and LL group were significantly higher than LC group, there are no difference between the rest group. In cell count of VEGF, LC group was significantly higher than CON group, LR and LL group were significantly lower than LC group, and there are no difference between the rest group. In cell count of bFGF, LC, LR and LL group all were significantly higher than CON group, LL group was significantly higher than LR group, and there are no difference between the rest group. The indicators of change in LC group verified the success of building the injury model for4weeks. The change of LR and LL group showed the way of rest or training under the injury intensity could promote repairation of the injury. Moreover, the change of LL group in cell count of bFGF indicated that the rise of expression quantity of bFGF means the training under the injury intensity stimulated the repair process when the repairation didn’t reach the level before the injury.Conclusion:After cyclic loading training for4weeks, rest for4weeks or training under the injury intensity for4weeks all has the obvious repair function for bone tendon junction injury. However, these two ways are different for tissue healing.