Ligamentum accessorium
Horses have two main check ligaments in each forelimb. The superior (proximal) check ligament is the accessory ligament of the superficial digital flexor tendon; it runs from the distal radius to the SDFT just above the carpus. The inferior (distal) check ligament is the accessory ligament of the deep digital flexor tendon; it connects the palmar carpal ligaments to the DDFT in the proximal to mid-cannon region. (The hind-limb equivalents are poorly developed or absent.) These ligaments act as passive restraints that help the flexor tendons support the fetlock and digit without constant muscle effort: part of the stay apparatus. They can be injured by over-extension, twisting, or fatigue. Desmotomy (cutting) of the inferior check ligament is sometimes performed to treat certain flexural deformities or to reduce tension on the DDFT in selected cases of navicular disease or laminitis.
Inferior check ligament desmitis is a recognized cause of proximal cannon-region swelling and variable lameness. Ultrasound is required for diagnosis. Superior check ligament injuries are less common. Surgical desmotomy of the inferior check is used for contracture of the deep digital flexor tendon in foals and for some chronic conditions in adults.
Swelling or heat on the back of the upper cannon bone that is not clearly the suspensory or flexor tendons should be ultrasounded. Sudden lameness after a twist or hard work can involve the check ligaments. Follow veterinary recommendations carefully after any desmotomy.
Inferior check ligament desmitis is a recognized cause of proximal cannon-region swelling and variable lameness. Ultrasound is required for diagnosis. Superior check ligament injuries are less common. Surgical desmotomy of the inferior check is used for contracture of the deep digital flexor tendon in foals and for some chronic conditions in adults.
Swelling or heat on the back of the upper cannon bone that is not clearly the suspensory or flexor tendons should be ultrasounded. Sudden lameness after a twist or hard work can involve the check ligaments. Follow veterinary recommendations carefully after any desmotomy.
See the Check Ligament on our interactive 3D horse model. Open 3D Model