As the cause is unknown the pathogenesis can only be speculated on. It is suspected that there may be a delay in the physiological maturation of the collagen of the flexor tendons or that contracture of the extensor tendons causes the flexor tendons to creep while the foal is still in the uterus.
Flaccidity of the flexor tendons is most common bilaterally in the limb, but can occur in the forelimb, in a single limb or in all four limbs as well. It is also related to premature foals.
Regardless of the process, flaccidity of the flexor tendons is seen by the dropping towards the ground when the foal weight-bears, the weight being carried on the heel of the foot and the lifting off the ground during the early stance phase of stride and tension or contraction of the carpal/tarsal and digital extensors. In severe or prolonged cases there may be subluxation of the distal interphalangeal joint associated with flaccidity of the flexor tendons.
Diagnosis of flaccidity of the flexor tendons is made through clinical signs and symptoms and radiography if subluxation of the distal interphalangeal joint is suspected.
Treatment is dependent on the severity of the flaccidity, but usually it is self-limiting. In mild cases the foal should be allowed controlled free movement and exercise, which is thought to stimulate the maturation process of collagen and promote organization of the collagen fibres. Most mild cases spontaneously resolve with exercise in - days. can be glued to the foot. These shoes have a 1 to 2-inch extension that goes beyond the heels. This encourages correct conformation of the limb and allows the flaccid tendons to tighten. More moderate to severe cases require corrective trimming or shoeing. In very severe cases where the foot is off the floor and the foal weight-bears on the palmar/plantar aspect of the pastern and the coffin joint is compromised or in cases where the extensors are contracted, surgical correction and splinting is an option though the prognosis for such cases is guarded. Flexural Limb Deformity – Contracted tendons A flexural limb deformity is a congenital, developmental or acquired deformity that causes a joint or joints to be held in a constant state of or hyperflexion. Congenital flexural limb deformities are caused by fetal , genetic predisposition or nutritional imbalance. In congenital cases the length of the bones exceeds the length of the flexor tendons at maximum stretch. growth and nutritional imbalances that result in the rate of longitudinal growth in bone exceeding that of the flexor muscles and tendons. Developmental flexural limb deformities are thought to be related to
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