LONG-TERM CONSEQUENCES OF EXPERIMENTAL DESMOTOMY OF THE ACCESSORY LIGAMENT OF THE DEEP DIGITAL FLEXOR TENDON IN ADULT HORSES

Objective-To evaluate clinical and biomechanical consequences of desmo tomy of the accessory ligament (AL) of the deep digital flexor tendon (DDFT) of equine forelimbs and determine whether this procedure is a v iable treatment for chronic desmitis of the AL-DDFT. Animals-6 adult S tandardbred trotters. Procedure-Biomechanical recordings obtained befo re and 6 months after desmotomy were compared. Walk and trot joint ang les, ground reaction forces, peak joint moments, and tendon forces wer e assessed. Results-Within 10 days after surgery, ail horses were soun d at a trot. Swelling, increased carpal flexion in the terminal stance phase, and incidental stumbling at the beginning of exercise were obs erved. Flexion angle in the carpal joints was significantly increased at the end of the stance phase. Peak moments around the distal interph alangeal joint and forces in the DDFT and AL-DDFT were decreased. Meta carpophalangeal joint angles, peak metacarpophalangeal joint moments, and peak loading of the suspensory ligament and the superficial digita l flexor tendon were unchanged. Conclusion-6 months after desmotomy, A L-DDFT strain was reduced without causing changes in joint angles or i ncreasing tendon loads or joint moments that could be considered hazar dous for the horses, Clinical Relevance-Changes in locomotion that rem ained 6 months after AL-DDFT desmotomy would be acceptable for horses with chronic desmitis if conservative treatment failed.