The recovery process of the equine locomotor system after desmotomy of the accessory ligament of the deep digital flexor tendon (AL-DDFT) was investigated by studying the movement patterns and joint moments in 6 horses before and 10 days and 6 months following surgery. Using a modified CODA-3 system the joint angles and angular velocities of the lower limb were assessed in the operated forelimb as before the operation. Simultaneously ground reaction forces were measured and joint moments calculated. At 10 days and 6 months after the operation the carpal joint started to bend earlier in the stance phase. At that instant, the fetlock joint was more extended and displayed a higher angular velocity. The moment of the coffin joint was significantly decreased 10 days after desmotomy. After 6 months it had recovered considerably, but still the shape of the curve was significantly different compared to that before the operation. The fetlock joint moment was not affected, but turned out to be generated for a greater part by the suspensory ligament and the superficial digital flexor 10 days after the operation. Further analysis of these results showed that 6 months after the desmotomy the locomotor system was able to cope with almost similar external moments. To accomplish this, it had adopted a new co-ordination pattern during the recovery process.
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