Equine Lameness: What It Is and How to Prevent It
Lameness. It strikes fear in the hearts of horsepeople everywhere, keeps grooms and owners up at night, and keeps vets busy. Having a horse come up lame is often a painful, expensive, and thoroughly disheartening experience. Lameness is the #1 cause of loss of use in horses.
While there is no 100% foolproof way to ensure your horse never, ever comes up lame, the good news is there is a lot we can do to reduce the likelihood of a horse going lame. It starts with understanding what lameness is, how to tell if a horse is lame, and understanding what causes lameness and how to prevent it.
What does it mean when a horse is lame?
“Lameness” is a catchall term used to describe any type of abnormality in a horse’s gait, most often due to pain in a limb. The opposite of being lame is being sound.
Lameness can range from mild – an extremely subtle, hard to detect low-grade discomfort, to severe – like an obvious limp or inability to move.
Lameness can also be chronic – like an older horse who takes shorter strides to compensate for the stiffness of arthritis, or acute – like a competition horse who spends three weeks on stall rest while an abscess clears up.
How to Tell if a Horse is Lame
Because lameness is a change in the horse’s normal way of going, the best way to spot lameness is to be familiar with how the horse moves and acts and then notice and investigate any changes.
That’s a lot easier said than done though, so here are a few signs that something may be amiss with your horse:
Signs of Lameness
-head nod or head high, moving above the bit
-stumbling or toe dragging
-personality changes, like pinning ears or becoming aggressive
-change in transitions; resisting or rushing transitions
-reluctant to move forward
-crookedness, asymmetrical shoulders or hindquarters
-inconsistent, poor quality canter or difficulty picking up one lead
-running out or refusing fences
-exaggerated change in gait when moving from soft to hard footing
-a leg that doesn’t move as far forward as the other one
-heat, swelling, tenderness, or other signs of injury
-back soreness or stiffness, which can indicate lameness elsewhere in the body
Most lamenesses are more pronounced and easier to diagnose at the trot than the walk or canter. If you suspect a horse is lame, you’ll likely be asked to trot the horse in a straight line for the trainer or vet.
If you suspect your horse is lame, you’ll need to consult an expert. This could be your trainer or coach first, then likely your farrier or vet, who may perform a lameness exam.
Lameness Exam
The first step of the lameness exam is giving your vet a thorough history of why you suspect your horse is lame, what you’ve noticed, and when it started happening. Be sure to mention anything new or out of the ordinary, like starting jumping training or a recent competition.
Next, the vet will examine your horse while he’s standing still. The vet will be looking at conformation, as well as checking for signs of injury like heat or swelling.
No lameness exam is complete without the horse trotting – the gait at which lameness is most easily detected, thanks to its easy 2-beat rhythm. Trot your horse on a loose lead rope towards and away from the vet, keeping the horse straight but without impeding or changing his movement.
Your vet will likely perform a flexion test next. This involves putting a specific joint, such as the shoulder, hock, or knee under flexion for a period of time (usually about a minute), releasing the bend, and immediately trotting the horse. Any soreness will be exacerbated at the trot after the joint has held flexion, making lameness easier to see.
Because many lamenesses start in the foot, hoof testers (a large prong tool that applies pressure to specific points on the foot) can help to pinpoint sore spots. Your vet may perform this, or you can also ask your farrier, who will know the most about your horse’s feet.
Depending on the results of these tests (and your budget), the vet may recommend nerve & joint blocks or medical imaging.
Nerve blocks (AKA diagnostic anesthesia) temporarily “block” the nerves to a joint or other suspect area. The horse is trotted before and after the block – if he trots normally after the block, the exact site of the lameness is determined.
Medical imaging includes techniques like radiography (x-rays for viewing bones), ultrasound (for viewing tendons, ligaments, and soft tissue), to MRIs, and CT scans for complex diagnoses.
Front End Lameness
Most, but not all, lameness cases in horses occur in the front legs. This makes sense, considering horses carry most of their weight on the forehand. Most forehand lamenesses originate from pain in the hoof.
Front end lamenesses are generally much easier to recognize and diagnose than hind-end lameness.
Most cases of forelimb lameness are caught not because of how the horse is using his front legs, but because of how he’s carrying his head – an abnormal head bob or nod is a common indicator of a front end problem, with the horse usually putting his head up when the sore foot touches the ground, and down when the sound foot touches the ground.
A helpful way to remember is “down on sound” – the horse’s head will drop down to its normal position as the sound foot touches the ground, and he’ll lift his head back up to try and take some weight off his sore, unsound foot.
Hind End Lameness
Hind end lamenesses are more challenging to diagnose properly, even for experienced horse people. Hind leg lameness is often very subtle, expressed by minor changes like one leg that doesn’t move forward quite so far as the other, or a slight occasional toe drag, instead of an obvious limp or head bob as you might see in front leg lameness.
Because there’s so much muscle in a horse’s hind end, it’s hard to see and feel the deeper joints and tissues, including when using medical imaging like ultrasounds and radiographs.
To help spot hind leg lameness, check for a noticeable ‘dip’ on one side of the horse’s hindquarters (this is best viewed when the horse is trotting away from you), or view him from the side and watch for one leg that doesn’t move so far forward as the other one – there’s a good chance that is the sore leg.
It’s important, if not slightly counterintuitive, to remember that the apparent level of discomfort is not necessarily an indicator of the structural severity of the problem (although his pain is still very real). For instance, a horse may exhibit more obvious signs of lameness for an abscess that will heal in a week or two than he will for a career-ending sesamoid fracture.
Common Causes of Lameness in Horses
It feels like horses can come up lame out of nowhere, despite all our best efforts. While some horses never seem to put a foot wrong and live long, healthy, issue-free lives, other horses are plagued by constant injuries, issues, flare-ups, and chronic problems.
The cause of each lameness depends completely on the individual horse and situation. But here are some common causes of equine lameness:
Hoof Problems
Many cases of lameness originate in the horse’s foot. While horses can suffer from dozens of foot problems, two common causes of acute lameness include hoof abscesses, bruises, and laminitis.
Abscesses
Abscesses occur when bacteria get trapped inside the hoof wall. Sand, glass, nails, stones, and other debris can all cause abscesses. Most abscess-causing bacteria enter just inside the hoof wall, where the wall meets the sole, and environmental moisture changes can increase the likelihood of abscesses.
Sudden lameness accompanied by heat or a pulse in the foot is a sign of abscesses, and any puncture injury to the foot can cause an abscess later.
You can prevent abscesses due to injury by treating any puncture wound as an emergency- call the vet ASAP, don’t remove the object causing the puncture (which could seal bacteria deep inside the hoof), and be prepared to soak the foot in a mixture of warm water and Epsom salts or iodine.
Treating abscesses needs to be done by a vet or farrier. Once the abscess is located, your farrier may pare away a drainage canal or remove parts of the hoof wall to release the pressure.
In the case of a deep abscess, your expert may advise waiting until it bursts out around to the coronary band (abscesses typically start at the bottom of the foot and move upwards), instead of removing huge chunks of hoof wall.
Bruises
Bruises are usually caused by stepping on uneven terrain, rocks, or gravel roads.
Bruises will cause acute pain and can often be spotted using hoof testers. Horses that are flatfooted or have thin or soft soles are most at risk for bruising.
Corns are another type of bruise, found more often in shod horses than barefoot horses. They’re caused by repeated trauma, such as a poorly fitting shoe or debris caught under the shoe.
Bruises and corns are characterized by painful discoloration of the sole, but the sole will often need to be pared away by the farrier to get a sense of the damage, which may appear as a reddish or brown welt around the site of the trauma.
Treating bruises is similar to treating abscesses, as your vet or farrier may need to release pressure by allowing the wound to drain. Pads or bar shoes may help the foot heal, and your expert might recommend additional therapies like Epsom salt baths or foot soaks.
Laminitis
Laminitis is inflammation of the sensitive laminae in the horse’s foot (the thin membrane that connects the hoof wall to the rest of the foot). It is extremely painful and can be fatal in some cases when humane euthanasia is required.
It’s most commonly caused by the horse’s diet – overweight ponies and chubby “easy keepers” (horses who gain weight easily) are most susceptible, but it can affect any horse (including Olympic dressage athlete Ramoneur 6, who pulled out of the Tokyo Olympic games due to a bout of laminitis). Metabolic diseases, certain steroidal medications, and prolonged work on hard footing can also cause laminitis.
Laminitis causes founder, a condition where the foot capsule has become unstable, and the pedal bone (AKA the distal phalanx) rotates within the foot. In extreme cases, the bone may penetrate the bottom of the foot. Once the pedal bone has rotated, the horse has foundered. In almost 5% of cases, a foundered horse is euthanized for humane reasons.
Treating laminitis depends on the cause and severity of the case and any resulting founder. Laminitis should always be treated as an emergency and seen by a vet immediately.
Treatment may range from rest and a change in diet to NSAIDs or extensive corrective shoeing and surgery.
Injuries
Injuries that cause lameness can involve anything from a kick while at pasture to an awkward step that pulls a tendon. Other injuries, like a heel cut or abrasion from bell boots can cause a horse to be lame until the wound has healed.
Using polo wraps, splint boots, or bell boots, when appropriate for the work, can help prevent or minimize lameness caused by injury. In some cases, these accessories prevent blunt force trauma, like bell boots protecting the coronet band, or can provide support and cushioning to tendons, like tension wraps.
Treating injuries depends entirely on the type of injury, so you’ll need to consult a vet or farrier for advice. If you notice heat or swelling, a flexible ice pack or cool hosing for 20 minutes at a time can help reduce swelling. Minor laceration and abrasion injuries must be kept clean and covered to prevent infection.
Conformation
The way a horse is made, especially lower leg conformation and hoof balance, will be one of the biggest factors in determining how often he’ll go lame.
While good conformation is no guarantee of perpetual soundness, horses with poor conformation are more likely to develop degenerative joint problems like arthritis or damaged tendons and ligament injuries.
What exactly ‘poor conformation’ means depends largely on what the horse is being asked to do (for instance, long, thin pasterns are desirable in a speed horse, whereas short, strong pasterns are desirable for a draft horse), but legs should be as straight and symmetrical as possible when viewed from the front and the side.
There’s not much you can do to ‘treat’ a horse’s conformation, so you’ll need to learn to work with it. Don’t buy a horse that isn’t physically well-suited to what you’re asking him to do, and understand your horse’s unique conformation and what it means for his future career. If he’s in great shape now but has crooked legs, he will have a shorter career as a competition horse, but can live a longer, more useful life as a pleasure horse.
Conclusion
Lameness in horses is a complex topic, with many causes, variables, and treatment and management options. Being aware of your horse’s job, conformation, regular behavior, and way of going can help you catch subtle changes before they become major problems.