Your top mare foaled down this morning. The sire is one of the top imported stallions, and you have the highest expectations. Six hours later you decide to have a closer look, and despondency attacks. The legs are all crooked! Have you wasted your money?

Don't despair! Many of these crooked legs straighten by the time the foal is a few weeks old. On the other hand, some deformities develop as the foal matures. Let's have a look at some of the problems that occur.

Angular limb deformities

These create crooked legs when viewed from the front or the back. A common example is a knock-kneed foal (referred to by veterinarians as carpus valgus), where the knees are too close together and one or both of the lower limbs are splayed out. The same condition can also be present in the hind limbs, involving the hock (referred to as tarsus valgus).

A third fairly common condition is known as fetlock varus, where the fetlocks turn out, leading to a toed-in conformation. These conditions can be congenital (where the foal is born with them), or acquired (where they develop after birth).

Congenital conditions develop while the foal is still within the dam's uterus, and can be influenced by a number of factors. These include the intra-uterine position of the foal, overfeeding of the mare during the last part of pregnancy, inflammation of the growth plates of the foetus, and incomplete ossification.

Some of the factors that lead to acquired conditions include poor conformation, overfeeding the foal, excessive exercise, injuries and lameness that leads to the foal carrying more weight on the sound limb.

Problems of the knee and hock are usually first approached conservatively. Stable rest and changes in feeding often rectify the problem. Corrective trimming, glue-on shoes and splints or casts, are also of use. If this does not work, surgery has to be performed. It is very important to make the decision to do surgery early, as it has to be done before the growth plates close – no later than five months of age.

Make sure that you take your youngster to a veterinarian with experience in equine orthopaedics, and heed his advice. Surgery varies from periosteal transaction, to the use of screws and wires or plates, all depending on the case at hand. Fetlock problems have to be referred for surgery straight away, and have to be operated on by the time the foal is two months old.

Flexural deformities

This refers to a problem where the joint involved cannot be fully straightened out (or extended), leaving the limb in varying degrees of flexure. Congenital flexural contractures can occur as a result of the position of the foal in the uterus, and most commonly affect the carpus or fetlock joint.

The acquired form often is the result of pain, caused by injury, rapid growth or overuse of the joint. They are more commonly seen during the growth phase, usually between 10-20 months of age.

One of the more commonly seen acquired flexural deformities involves the coffin joint. It occurs in foals between six weeks and six months of age, and usually affects only one forelimb. In this condition, the foals walk with their heels slightly elevated from the ground, and excessive heel growth occurs as a result of too little ground contact and a lack of normal hoofwear. This results in a boxy foot, often referred to as a club foot. Once again, these cases are usually approached conservatively, with corrective trimming the method of choice.

Some farriers use toe extensions, but these can cause secondary problems such as fractures of the dorsal hoof wall. Should corrective trimming not work, surgery (sectioning the distal check ligament) is indicated. Corrective trimming must be continued after surgery to give the foal the best possible chance to recover.

Another common acquired problem affects the fetlock joint, and is seen in horses 12-24 months of age. The animal becomes more upright through the fetlock joint. In some the leg appears rather straight, while in others the fetlock bends forward (flexes) so that the horse cannot bear weight on the joint.

Sometimes, in less severe cases, non-steroidal anti-inflammatories can be beneficial. If these appear to have an effect, continued treatment with stable rest might have the desired result. However, surgery is often the only way out, followed by aggressive physiotherapy. The prognosis is guarded, and in severe cases it is often necessary to destroy the horse on humane grounds.

The take-home message? Intervene as early as possible. Limb deformities that are present at birth and do not show major improvement within the first month, need to be seen by a veterinarian. The same applies to all deformities that appear at a later stage. The sooner action is taken, the better the chances that permanent abnormality can be limited to the absolute minimum.