A Leg at each Corner
Paul Farrington, B. Vet. Med., MRVCS, describes the most common causes of lameness and provides some tips on how they can be prevented.
The classic phrase 'No foot, no horse' is undoubtedly true; the most common causes of lameness in horses are foot related. Foot injuries probably account for more than 50% of incidents of lameness, with about 35% occurring somewhere between the foot and the knee or hock.
One of the main differences between joint lameness to the foreleg and hind leg is that in the foreleg they tend to be more common in the fetlock rather than in the knee whereas in the hind leg, although fetlock problems still occur, you also get many lamenesses associated with the hock, such as spavin. These are often associated with dressage horses or horses that are continually worked on a circle rather than used for general hacking and 'straight line' work.
Injuries to the foot
Foot lameness can be caused by disease, such as navicular disease, but more commonly occurs through injury. A simple bruised sole is probably more frequent than anything else, particularly in areas of the country where stones and flints proliferate and when horses are working on hard ground. We also see 'tread' injuries (overreach) on to the foot or barbed wire injuries when the horse puts its foot through the wire and pulls back.
One of the most common consequences of injuries to the foot is infection leading to pus in the foot. A horse may tread on a stone and be sore for 24 hours and then appear to recover but three days later it becomes very lame as the infection develops. The vet or farrier then has to dig out the pus so that the infection can be treated.
If you bring the horse in from the field or you come back from a ride and the horse is a little bit lame, don't just clean the foot with a hoof pick use a brush to scrub it out with water and clean the sole to see if you can see any sign of where an impact may have occurred. If it is very fresh and has penetrated the foot significantly there may be blood but sometimes the horse can stand on a nail or stone and there will be no visible sign.
Heat tends to develop quite quickly after that and the outside of the hoof will feel warm to the touch. One of the first things that the vet will look for in terms of trying to diagnose the area of lameness is feel for a digital pulse, which can be detected between the fetlock and the foot. A strong, pounding pulse will indicate that the problem is in the foot. Then hoof testers will usually indicate the area involved where the pain is most acute.
Another common foot injury is corns, which are the result of bruising of the sole between the bar and the hoof wall. This can be the result of poorly fitting shoes. It is very important that you keep your horse's feet in good condition; therefore don't leave shoes on for too long and make sure your horse is seen by the farrier at regular intervals.
Accidental external injuries
Moving further up the leg the next most common cause of lameness is the accidental external injury - wire wounds, kick injuries, scraping the leg on a fence, wall or hedge as they are jumping.
Each injury has to be judged on its own merits - if you are unsure of anything that you are looking at always call your vet. It is better to call out the vet for a false alarm than do nothing for two or three days to see if the injury improves and risk the problem developing into something more serious. If you are not sure at least call the vet and have a word over the phone. The vet may feel that advice is sufficient or decide whether the horse should be seen.
If you take a wire injury, for example, it may appear that the horse has just scratched itself on barbed wire and although he may be quite lame, as anyone who has cut themselves with a knife will know, even a superficial cut can be very sore. But how do you know if it is just superficial or, if it is close to the joint, whether it has penetrated to the joint or tendon sheath?
Even if you are confident that the wound is superficial always make sure that the horse's tetanus vaccination is up to date.
If it is a wound that requires stitching the sooner that it is seen the more likely it is that any treatment will be successful. Decay and infection can start from the moment the wound occurs so if you notice an injury in the evening, don't leave it until the next morning, as sometimes that can be too late. It is far better to be safe than sorry.
Traumatic injuries
The horse is subject to trauma simply because when it is exercising the stresses going up the limb can be high. It is also subject to overstretching, twisting and concussion etc.
Traumatic injuries can be acute or develop gradually due to progressive wear and tear.
Acute traumatic injury: a sudden injury such as when the horse puts his foot down a rabbit hole and twists his leg.
Progressive wear and tear: if the horse is never allowed periods of recovery then the wear and tear on the leg, or 'miles on the clock', inevitably lead over a period of time to injuries developing. The human requirement for athleticism at the top level stops around the age of 35 - we're all advised to take exercise every day but the level of activity diminishes after a certain age. However, horses are still asked to compete at a high level at the age of 18 and often compete in dressage well into their 20s.
Owners and riders sometimes expect too much of their horse. If you're not capable of running 100 metres in ten seconds you're never going to be able to, it doesn't matter how hard you train. That's easy to quantify in racehorses as they either win races or they don't and people quickly realise their level of ability but in the case of the general purpose Riding Club horse, riders need to understand their horse's capabilities and limits.
One of the major areas of wear and tear injury is in the tendons and ligaments. The horse's tendons and ligaments, like any other tissue of the body, are continually growing and being replaced so if the degree of work is causing breakdown at a faster rate than the body can replace the tissue you will then get gradual tendon breakdown.
A tendon or ligament injury can also occur as an acute breakdown because the horse has just been exerting too much stress - for example, during a point-to -point - or because it has overstretched by putting its foot down awkwardly on uneven ground.
Muscle strains, whether in the shoulder, back or hind leg are all too often secondary to another problem. A primary muscle strain can occur if a horse falls over or overstretches, but very often the horse has another underlying problem that then affects the back as the horse tries to correct its way of going to carry the injury.
Another important factor in lameness is conformation. If a horse has poor conformation then its legs do not absorb the stresses in the way that nature intended; the horse is going to be more susceptible to injury.
Fitness
A lot of people have great difficulty finding safe hacking nowadays but if a horse is just going round in circles in a school they don't achieve the same level of fitness. If you want to do cross country events the horse needs to do roadwork, hill work etc to get a proper cardio-vascular level of fitness and the right muscle tone. If they don't have the right muscle development then that is going to predispose them to injury.
If you are going to compete take advice regularly. Go for lessons because if you are riding the horse in an incorrect manner that can also lead to injury. If you are going to ride across country not only must your horse be fit and capable of tackling the challenge but you as the rider must be competent to face the demands of the competition. If you are properly prepared you will gain far more enjoyment from the experience.
Lameness due to disease
Although there are joint problems associated with the knees and fetlock, most diseases that cause lameness are again foot related. Two of the most common are laminitis, which is associated with management and/or disease such as Cushings disease, and navicular disease, which can be associated with poor conformation and collapsed heels leading to increased concussion.
Identifying signs of lameness
When you go in to the stable first thing in the morning and before you bring the horse out of the stable, feel for heat or swellings anywhere on the legs that you haven't noticed before. It is much easier to detect heat in the leg in the winter than the summer. If the horse wears bandages in the stable, take them off and let the horse stand for an hour before you check the legs.
It is very important in terms of your initial assessment of a lame horse to:
- Use your eyes
- Use your hands
- Make sure that what you are looking at is really clean. You cannot make a proper assessment of a horse in a muddy field so bring them in to the yard and make sure you can see the problem area.
What you are looking for is:
- Heat and swelling
- Wounds
- Lameness
If you think the horse is lame, trot him up on a hard surface, ideally for someone else to look at. If the horse is obviously in pain then call the vet immediately.
Top Tips for Preventing Lameness
- Practice good stable management and care of the horse.
- Pick the horse's feet out twice a day so you can look at the sole and the shoes.
- Check the shoes and ensure clenches are still tight and the head of a nail has not come up that could produce a brushing injury on the other leg.
- Keep feet and shoes in good condition.
- Avoid injuries by good management and care of the field - make sure fencing is in good repair and avoid barbed wire if possible - and the stable - check for nails that might be sticking out, splinters in the wood etc.
- Only work your horse according to its capability and level of fitness.
- Avoid trotting downhill but steady trotting on the level or slightly uphill is good for building up fitness.
- Avoid working your horse too much on hard and/or uneven ground.
- Exercise boots, particularly in front, are a good idea for normal exercise and can prevent injury from knocks etc.
- Make sure your horse's vaccinations are up-to-date.
- If in doubt call the vet.
