Find a hoof expert
Become a partner
Club foot – the congenital, acquired and false club foot
What is a club foot?
In a club foot, one of the horse's flexor tendons is shortened, causing the hoof to stand too upright and appear "clubbed". Most often it is the deep flexor tendon that is too short, permanently flexing the coffin joint. However, the superficial flexor tendon can also be shortened, in which case the continuous flexion occurs in the coronet or fetlock joint instead. Some equine professionals refer to this second variant as a "tendon stilt foot", while others use the term synonymously with "club foot". There is no uniform definition of these two terms, nor is there any consensus on when a hoof is considered a club foot. Some speak of a toe wall angle of 60° or more, while others use the deviation of the bony column of the coffin bone, short pastern bone and long pastern bone as a reference.
In principle, a club foot can occur on one or more legs, and both front and hind hooves can be affected; however, a club foot is more commonly seen on a front limb.
On the hind hooves, a club foot is often found together with sinking pasterns (i.e. a weakness of the suspensory ligament), which is ultimately referred to as "bear-pawed".
A club foot can occur in various degrees of severity and can range up to floating heels, or such severe cases in which the foal cannot bear any weight at all on the affected limb.
True or false club foot?
A true club foot exists when the horse is physically unable to extend the toe joints of the respective hoof. A false club foot, on the other hand, is a hoof that looks like a club foot, but where the horse would physically be able to fully extend the toe joints. That means the tendons would be long enough, but the hoof still appears too upright (the heels are too high and the toe is overloaded).
There can be numerous causes for a false club foot:
- uncomfortable heel area (incorrect/infrequent hoof trimming, thrush, etc.)
- cause further up in the horse's body (pain in the shoulder, problems with the flexor musculature and the like)
- husbandry problems (too little movement, ground that is too soft)
So how can it be determined whether it is a "true" or "false" club foot? To do so, the veterinarian can perform a stretch test: the hoof is placed on the end of a board, so that the rest of the board points towards the horse's head. This end is then slowly lifted. If the hoof remains flat on the board, the flexor tendons are stretched, showing that they could be stretched further. If, on the other hand, only the toe remains on the board and the heels "lift off" (with the limb extended), this is a sign that the flexor tendons cannot stretch any further and it is a true club foot.
A true club foot can also be either congenital (i.e. the foal is born with this malformation) or acquired during growth.
Consequences of a club foot
With a club foot, the permanent upright position of the coffin bone overloads the toe area of the hoof. On the one hand, this mechanically "levers" the toe wall away during break-over, which can lead to a widened white line despite a healthy laminar layer. On the other hand, the toe area is worn down excessively, which sometimes results in a thin sole. In addition, the coffin bone will slowly remodel due to the ongoing unphysiological pressure: the bone is broken down at the tip from below and develops a bony proliferation at the lower end towards the toe wall. The coffin bone of an adult horse with a club foot can therefore ultimately look similar to the coffin bone of a laminitic horse with coffin bone rotation.
Without countermeasures, a club foot tends to worsen over the course of the horse's life and can sometimes lead to knuckling over. In this case, the fetlock joint is pushed forward and no longer flexes normally during movement.
Treatment of the club foot
When it comes to treatment options, the age of the horse is decisive. In a foal, all structures are still growing and can therefore be influenced to a certain extent. Close cooperation between hoof trimmer, veterinarian and owner is important here during the first six months of life. During this period, the growth plates of the lower bones are not yet closed and the greatest influence can be exerted. After that, the options are already limited.
Treatment options during foalhood include:
- shortening the heels
- applying cast bandages
- artificial extension of the toe by applying extended rigid glue-on shoes or splints
- plenty of movement on hard ground
- administration of oxytetracycline (an antibiotic that has the side effect of inhibiting bone growth; however, the exact mechanism of action with regard to improving the club foot has not yet been fully clarified)
In severe cases, surgery can also be performed in which the accessory ligament of the deep flexor tendon is severed.
Once the horse is fully grown, a true club foot can hardly be completely corrected any more. However, with good management, improvements can be achieved and the horse can lead a trouble-free life (depending on the severity). Management measures include:
- very short trimming intervals (in some cases every 1-2 weeks)
- making the heels "comfortable", i.e. ensuring a physiological development of frog and bars
- plenty of movement
- sufficiently hard ground in the paddock
A false club foot, on the other hand, can be completely cured with good hoof trimming. Here too, very close-interval hoof trimming is necessary, and permanent hoof protection may be useful for a certain period of time to protect the overloaded toe from too much abrasion.
Causes and prevention
There are many circumstances that can contribute to the formation of a club foot, and not all of them are scientifically clearly proven. Likewise, the causes must be differentiated depending on the type of club foot:
possible causes of congenital club foot:
- inadequate nutrient supply of the pregnant mare (especially a deficiency of calcium, phosphorus, copper and vitamin A, vitamin D3 and vitamin E)
- incorrect position of the fetus in the uterus
- an unfavorable size ratio between the stallion and the dam
- imbalance between the muscles that flex the leg and those that extend the leg
- a hereditary cause/genetic predisposition (contradictory studies)
possible causes of acquired club foot:
- uneven growth spurts (bones grew faster than tendons)
- intake of concentrated feed or food that is too high in energy and protein during growth
- injuries (e.g. tear/rupture of the extensor tendon, which acts as an antagonist to the flexor tendons)
- protective posture due to illness (e.g. shoulder joint cyst, epiphysitis)
- incorrect hoof trimming (including removal of the "foal beak")
- incorrect husbandry (too little movement, keeping only on soft ground)
The last points (injuries, protective posture, hoof trimming, husbandry) can also be the cause of a false club foot. Likewise, hoof diseases (e.g. thrush) can lead to the horse no longer bearing weight normally on the heels, causing an artificial club foot to develop.
Special form: joint stilt foot
In the vast majority of cases, a club foot is a so-called "tendogenous stilt foot"; this means that the pathological upright position of the hoof is caused by the shortening of the deep or superficial flexor tendons. However, there is another type of club foot, namely the "arthrogenous stilt foot"; this is also called "joint stilt foot", since the cause here does not lie in shortened tendons, but in diseases of the joints involved.
Author: Nathalie Kurz
