Osteoarthrosis, more commonly known as «arthrosis» or "degenerative joint disease",is a common joint disease that is very frequent in humans, but also in horses! All the more so as equitation, depending on the discipline (show jumping, dressage, eventing, racing, show, barrel racing...), the training and care given to the horse (preparation, warm-up, physiotherapy, etc.), can put the horse’s joints to a severe test.
Osteoarthrosis is a progressive degenerative disease of the cartilage in the bones of a joint. Depending on its stage, it causes stiffness, lameness, difficulty in moving, and even problems for feeding...
If osteoarthrosis is very often associated with old horses, young horses are no less prone to it when their joints are heavily solicited during work.
This disease is multifactorial:apart from old age, many factors can be the cause of the onset of early osteoarthrosis in the horse.
Although the onset of osteoarthrosis is feared, it does not systematically call into question the continuation of the horse’s sporting career. There are multiple solutions to coun- teract the progression of osteoarthrosis and means of offering support to the joints of the horse with osteoarthrosis.
Let’s take a closer look.
I. What is Osteoarthrosis?
a. Composition of a joint
First of all, it is good idea to (re)define what a joint is.
A joint, is a junction between two bones: roughly speaking, it allows the bones of the skeleton to be held together, and it is also what gives it a certain mobility.
Cartilage is located at the two bony ends of the joint. It has two main functions: it protects against friction between the two bones (the bony surfaces slide over each other), and considerably absorbs shocks. Thus, when the horse performs a movement, it guarantees the fluidity of a movement without pain (flexion, extension, rotation).
Within the joint, the cartilage is immersed in a liquid called synovial fluid, contained in the joint capsule and secreted by the synovial membrane. This fluid is mainly composed of water (rich in nutrients, mineral salts and hyaluronic acid). Its main function is to feed and lubricate the cartilage cells, the chondrocytes.
b. Cartilage degeneration
The onset of osteoarthrosis in the horse follows a natural process of wear and tear. Over time (or following traumas stemming from multifactorial causes), the articular cartilage will gradually degenerate. The affected areas will gradually become devoid of cartilage
As the cartilage thins and crumbles, it loses (among other things) its shock-absorbing properties and the stress on the bones increases. This degenerative process will lead to a chain reaction within the joint and mobilise all of its constituents until inflammation occurs.
In cases of advanced osteoarthrosis where the cartilage has completely disappeared, the joint is painful and the horse, even at rest, has difficulty moving (stiffness, lame- ness). In order to compensate for the pain, the horse uses the surrounding muscles, ligaments and tendons. However, the over use of, and stress to these tissues can also be the cause of secondary damage.
It should be noted that cartilage has little or no healing capacity. Once damaged, cartilage cannot regenerate. The damage caused by osteoarthrosis therefore irreversible.
The joints most affected are located in the foot, fetlock and hock (see diagram below), which come under pressure daily, notably depending on the horse’s body condition and physical activity.
II. How do you know if your horse is suffering from osteoarthrosis?.
a. What are the causes of osteoathrosis in the horse?
The prevalence of this pathology increases with age, as cartilage naturally deteriorates as the horse gets older. It is therefore very common to see osteoarthrosis in older horses.
However, there are other factors that give rise to micro-lesions in the cartilage favouring the development of osteoarthrosis:
CAUSES AND RISK FACTORS FOR OSTEOARTHROSIS
Unsuitable training sessions: too frequent, long and intense, for a horse with a lack of preparation/warming up, suffering from deficiency or whilst still growing... can be traumatic. The speed, the brutal movement and the repeated impacts are harmful for his joints.
Similarly, the quality of ground is also important: working frequently on surfaces that are too deep or too hard will have its consequences. Working on hard ground has a direct impact on the joints; on the other hand, a soft and deep surface puts pressure on the tendon.
It is therefore recommended to work on varied terrain and/ or to alternate training on soft and hard ground.
[LIMB CONFIRMATION DEFECTS]
Confirmation of the limbs and feet includes the way in which the horse stands on its four legs and moves. Defects in limb confirmation (which are deviations that do not meet the standard correct criteria) will have repercussions on the joints, muscles and tendons of the entire locomotor system.
The correction of these defects is a determining factor to the quality of the locomotor system. In order to do this, regular attention from a farrier is essential, and this, right from the horse’s earliest age.
ndoubtedly, carrying excess weight (without necessarily talking about obesity) will favour the appearance of osteoarthrosis in the horse, and particularly in the joints of the locomotor system (limbs).
Osteoarthrosis is not hereditary.
Instead, there are osteoarticular diseases, such as osteochondrosis, (a multifactorial disease which has a genetic factor) which predispose to the development of (early) osteoarthrosis.
⏩ This article might interest you: Osteochondrosis in horses
[INJURIES, CONTAMINATIONS AND INFILTRATIONS OF THE JOINT]
Apart from injuries caused by a fall or an accident, other events can also affect the cartilage, such as:
- contamination of a joint by pathogenic agent;
- complications related to a surgical intervention;
- certain intra-articular injections (infiltrations with steroidal anti-inflammatory drugs, corticosteroids, etc.).
b. What are the symptoms of osteoarthrosis and how is this pathology diagnosed in the horse?
The course of osteoarthrosis in the horse is unpredictable. Osteoarthrosis can develop more or less rapidly (over a few months, or decades), and unexpectedly.
As the damage is irreversible, it is important to detect the first signs of joint discomfort in your horse.
- Stiffness, resistance before/during warming-up;
- Swollen, hot joints;
- Difficulty moving;
If suspected, we invite you to consult your vet.
Following a physical examination of the horse, and with the help of X-rays of his joints, he will be able to confirm or not the diagnosis. Although cartilage is not visible on the X-rays, the vet will be able to examine the impact on the bones.
III. How can relief be offered to a horse with osteoarthosis?
a. Veterinary treatments
After clinical examinations and depending on the stage of the osteoarthrosis, the veterinarian can prescribe different medical treatments to relieve pain in the horse suffering from osteoarthrosis.
Non-steroidal anti-inflammatory drugs (NSAIDs) are prescribed by the vet. They will act directly on the inflammation to reduce swelling and decrease pain. Pain is very common in horses suffering from osteoarthrosis. The use of NSAIDs follows a pain management protocol aimed at improving their quality of life and favouring the amplitude of joint movement and therefore mobility. It is important to follow your vet’s recommendations for the appropriate use of these drugs.
In the case of intra-articular infiltrations or injections, the vet injects a combination of different molecules into the joint capsule. These may be steroidal anti-inflammatory drugs, or IRAP and PRP (preparations made from the patient’s own serum and blood), hyaluronic acid (one of the major components of the joint capsule) or polysulfated glycosaminoglycans.. The latter are used in particular for their anti-inflammatory effects and chondroprotective properties, without harmful effects.
Biphosphonate treatments (intravenous or intramuscular injections) slow down the activity of osteoclasts (= bone cells involved in the resorption of «aged» bone tissue - before it is rebuilt by osteoblasts when the system is functioning properly). This has the consequence of reducing osteolysis (destruction of bone tissue). Among the commonly used molecules for these conditions are tiludronate and clodronate (in the case of navicular disease and sparvins for example).
Mesotherapy is a practice used in the treatment of pain. It involves injecting tiny amounts of medication (different combinations of molecules) locally on or around the areas to be treated. This treatment is particularly prescribed for back pain and cervical osteoarthrosis.
Shockwave therapyis therapy by shock-waves, or extra acoustic waves, with the aim of relieving pain at different levels of the tissues.
Arthrodesis (joint fusion) is a surgical operation to weld two joints together.
b. Feed supplements
Osteoarthrosis is a condition that cannot be cured.
The use of feed supplements helps to relieve the symptoms of horses suffering from osteoarthrosis and to slow down its progression. However, one should not expect complete regeneration of the destroyed cartilage surface.
Find our range of supplements for osteoarthrosis in horse.
Among the ingredients that we favor in the support of the articular system, we find:
Glucosamine is the precursor of several components of proteoglycans and hyaluronic acid. In cartilage, hyaluronic acid is bound to proteoglycans and forms aggregates that ensure the proper hydration of this tissue. In the synovial fluid of the joints, hyaluronic acid acts as a lubricant and chondroprotective agent.
Chondroin is a constituent of proteoglycans whose role is to maintain good hydration of cartilage and bones. In addition, it directly protects cartilage cells against enzymatic reactions and free radicals.
MSM, or methylsulfonylmethane, also has chondroprotective properties. It is also a source of organic sulphur, which is essential for the synthesis of collagen, a protein found abundantly in cartilage that gives it its properties of hydration, strength, elasticity and flexibility.
Numerous clinical studies have scientifically validated the effectiveness of these three chondroprotective agents.
[AVOCADO AND SOYA UNSAPONIFIABLES]
The unsaponifiable fractions of avocado and soya oils improve healing of joint lesions located in the synovial membrane and cartilage tissue. They also increase the synthesis of glycosaminoglycans (proteoglycan components)) within articular cartilage.
c. Hoof care
In general, care of the foot by a farrier is of utmost importance. It must be regular to prevent any deviations and to rebalance the distribution of the body’s weight on the feet. Depending on the various deficits observed, and in collaboration with the vet, trimming and/or shoeing are means of mechanical correction to compensate for imbalances and reduce pain linked to osteoarthrosis..
A suitable environment
It is recommended to keep the joint mobile.
Without talking about physical activity, movement allows the joint functions to be solicited and the muscles adjacent to the joints to be worked .
The monitoring of the horse’s body condition must also be taken very seriously. Indeed, it should be remembered that being overweight is one of the main factors that can encourage the onset of arthrosis, and aggravates the symptoms in the case of proven arthrosis.
IV. Osteoarthrosis and performance, conclusion?
As you will have understood, in preventing joint problems, and in particular the onset of osteoarthritis, prevention is key.
The horse’s joints are sensitive and become vulnerable as he ages. It is entirely possible to prevent the onset of joint problems by adopting the right measures: a balanced diet covering the daily nutritional requirements and regular hoof trimming.In young sport horses, preventive sup- plementation with chondroprotective agents helps to reduce the risk of joint problems.
The presence of osteoarthrosis in sport horses is common and does not necessarily mean that they stop com- peting. The development of osteoarthritis is closely linked to the pursuit of performance (top level sport), and sport horses are the most exposed.
A horse can continue to perform despite the beginning of osteoarthrosis.Indeed, many solutions exist to relieve the pain from osteoarthrosis and to slow its development, notably through feed supplements. Nevertheless, it is essential to adapt training and work intensity levels to the evolution of the arthrosis and the degree of degradation, and to ensure regular monitoring of its evolution.