Flexural Limb Deformities in Horses

By Garrett Metcalf, DVM

Almost every horse person has heard of contracted tendons in a horse, but flexural limb deformities (FLD) are a little more complicated than just tight tendons. There are different locations or joints involved with FLD and different age groups of horses that experience these types of deformities. Treatment options among these groups or types of FLD are quite different so understanding these types of deformities is important in picking the correct treatment plan.

Congenital Flexural Limb Deformities –

Congenital FLD are deformities that are diagnosed at birth of a newborn foal. These deformities can affect the carpus, fetlock or the coffin joint. The most common area for a foal to have a FLD is in the carpus. It is not clear what causes these deformities in newborn foals, and uterine malposition of the foal is often blamed, but in newborn children with club feet it is thought that lack of fetal activity leads to abnormalities in their limbs. Other causes that have been suspected to cause FLD are genetic causes, toxins that the mare ingested during pregnancy, illness in the mare and poor nutrition. Regardless of the cause of the FLD in foals, these problems need to be addressed as quickly as possible in order to fully correct the FLD without complications.

Medical treatment options –

Newborn foals with FLD should be examined by a veterinarian to determine the best treatment plan and to monitor progress to determine if the treatment plan is working or needs to be changed. Foals that can stand and nurse without assistance rarely require treatment unless the FLD gets worse. These mild cases are usually confined to a stall and then allowed to have small amounts of daily exercise to allow the limbs to strength without over tiring the foal to the point of causing more harm. The goal of controlled exercise is to allow slow relaxation of the flexor tendons along with strengthening of the extensor tendons to correct the FLD over time. Within a short period of time, the foal becomes stronger and is able to straighten and relax its limbs to a point of normal conformation.

Some more moderate to severe cases will require treatment with a drug called oxytetracycline given slowly intravenously in IV fluids to help relax the tendons. Sometimes this treatment alone is successful to straighten foals’ limbs, but it works better in combination with splinting of the limbs. There is some risk of kidney injury with using oxytetraycycline in foals so it must be administered by a veterinarian and is recommended that it is administered with IV fluids to minimize possible renal injury. Splinting a foal also comes with its own risks. A foal’s skin is very delicate, and proper splint placement with good padding is paramount to prevent complications from splints. Foals that require splints must absolutely be kept in a stall while in splints and must be closely monitored in case problems do arise. Foals in limb splints can require assistance to stand so they can nurse as well.

Corrective shoeing has been employed to help correct some FLD in the lower limb. There are commercially available shoes that are glued on to the foal’s feet, but these can be difficult to keep on. Sometimes custom-made shoes out of aluminum plate or toe extensions out of acrylic material can be used to help with FLD in foals.

Pain management in foals is also helpful in correcting these FLD. It is often painful while stretching the soft tissues out with splints or corrective shoeing so often these foals are administered NSAIDs to help with the pain and inflammation associated with this process.

Read more in the August issue of Oklahoma Farm & Ranch.