After removal of external fixation, it is important to pay attention to safety and start functional rehabilitation training. After a long period of external fixation, you cannot rush to walk at this time. The dorsal extension angle of the injured foot is still at a low level, and the serious lack of strength, flexibility and balance are not enough to meet the functional requirements for normal walking. Without the protection of external fixation, this is still a dangerous time window for secondary rupture. Generally speaking, 6-8 weeks is the first risk time window for secondary rupture, when the external fixation has just been removed, if there is unexpected sudden weight bearing on the forefoot, causing rapid plantarflexion reaction, secondary rupture is more likely to occur. 10-12 weeks is the second risk time window, when the Achilles tendon is At this time, the Achilles tendon is physiologically starting to replace the original fibrous scar with healthy tendon tissue, so strenuous exercise should still not be performed, especially avoiding rapid forefoot weight bearing. However, slow walking should not be a problem in terms of time. The third window of time is the early practice of jumping, which should also be done in a gradual manner from simulated jumping, small jumping, and large jumping. In general, recovery training with the Achilles walking boot after the cast is removed and avoiding sudden force on the forefoot is the key to prevent secondary rupture. It is normal for the injured foot to be swollen and the Achilles tendon to be thick and hard when the external fixation is just removed. It is generally recommended to use the Achilles tendon boot after the long cast, when using the angle to 90 degrees, and put three heel wedge pads under the cloth cover. After a week of use, those who recover quickly can remove the bottom layer of heel pads, and remove one every week or one more day, after three weeks. Removal of the heel pad should also be determined according to the recovery of the individual to avoid overstretching the Achilles tendon and re-injury. When the angle is restored to the point where the forefoot can be upturned, adjust the angle of the boot to allow the boot to move within a certain range, the swing angle should not be too large, it must be less than the range of motion of the ankle joint, so as to help the patient recover better. Poor quality Achilles boots tend to lose color when used, often infecting the wound, and because of the poor material used, they do not hold the ankle firmly and are prone to secondary fracture.