Affecting both sides (i.e. the left and the right). Usually described as ‘bilateral forelimb lameness’ (both front legs are affected) or ‘bilateral hind limb lameness’ (both hind legs are affected).

An individual bone of the horse’s knee joint (the carpus), which is equivalent to the human wrist.

Persisting for a long time or constantly recurring.

• A compulsory veterinary examination of a horse to assess its suitability to race. It includes a physical examination (including listening to the heart with a stethoscope), an examination of the musculoskeletal system and examination of the horse for lameness by observation of the horse trotting.
• A CVC is issued by the Club for veterinary conditions that require veterinary investigation, management and follow up but which have a relatively low probability of affecting a horse’s medium to longer term health, welfare and racing performance.
• CVC are a means to help ensure that horses are provided with appropriate veterinary care and are assessed by the stable veterinary surgeon prior to returning to racing.

Colic is a common name for abdominal pain. Colic surgery in the horse often involves correcting intestinal twists and obstructions.

• Dorsal Displacement of the Soft Palate (DDSP) is a condition that typically occurs as the horse fatigues towards the end of a gallop or race and in which the horse’s soft palate displaces upwards from its normal position in the throat to lie on top of the epiglottis at the entrance to the larynx and trachea.
• When this occurs the airway is obstructed and this typically (but not always) causes an abnormal breathing noise (usually a harsh gurgling sound) and reduced performance.
• The horse typically corrects the position of the soft palate by swallowing soon after it pulls up from the exercise and so the condition can usually only be accurately diagnosed by scoping the horse during exercise (see Dynamic Endoscopy).

Inflammation of a ligament.

An examination performed to measure and record the electrical activity of the heart and to diagnose cardiac arrhythmias (irregular heart rhythms) that may affect the health and / or racing performance of a horse, for example, atrial fibrillation.

• A condition in which the soft tissue including the aryepiglottic folds and the tissue that normally lies underneath the epiglottis between the base of the throat and the tongue comes up to envelope (‘entrap’) the epiglottis (a triangular cartilage) that forms part of the structures that guard the entrance to the airway during swallowing.
• The tissue may billow like a sail when the horse exhales during exercise which may interfere with airflow during breathing and sometimes causes an abnormal respiratory noise.
• In chronic cases the entrapped tissue can become swollen, inflamed and ulcerated causing greater breathing problems during exercise and sometimes coughing or a choking/gagging sound when eating.

• A condition in racehorses in which the fragile small blood vessels that surround the air-sacs (alveoli) within lungs and, which facilitate the uptake of oxygen during breathing rupture due to the large pressure difference between blood vessels and the airways during strenuous exercise causing bleeding into the airways.
• This lung bleeding may result in the presence of blood at a horse’s nostrils after exercise in which case the horse will be declared to be an official bleeder and stood down for racing for a period to allow the lungs to heal.
• Lesser degrees of bleeding into the lungs after exercise may be detected by scoping the horse (endoscopic examination) after exercise – this may be referred to as ‘blood on scope’ or EIPHS and is scored from 1 (very mild) to 4 (severe).
• EIPH is a relatively common cause of poor racing performance.

A blood-filled swelling often caused by trauma with rupture of blood vessels and bleeding into tissues, for example in muscle tissue or under the skin.

An abnormal heart rhythm. Sometimes detected during a post-race veterinary inspection of a horse and which may have affected the racing performance of that horse. The most common abnormal heart irregularity in racehorses is atrial fibrillation.

• This term is used to describe the bright areas seen on a nuclear scintigraphy ‘bone scan’.
• Such 'hot spots' are areas of bone in which there is a high level of bone activity and these may indicate bone stress injury or stress fractures.
• IRU also normally occurs at the growth centres (the growth plates) of the long bones.

An increased volume of fluid within a joint which is usually caused by injury and inflammation of joint structures.

Heat, pain and swelling of a joint often causing the production of watery joint fluid that does not lubricate and protect joint surfaces as well as healthy joint fluid.

Lameness is an abnormal way of locomotion caused by the horse trying to relieve musculoskeletal pain and / or protect an injured structure during movement. It is usually graded in severity from grade 0 (normal) to 5 (unable to bear weight on the limb).

• A disease that effects the upper airway in horses and causes a dramatic decrease in airflow to the lungs leading to reduced performance.
• The condition is caused by disease of the nerve that supplies the muscles that are important in opening the throat widely during exercise. Usually the left side of the throat is affected.
• Horses affected with this condition make a characteristic ‘roaring’ noise during exercise which gets worse as the condition progresses and the airway is increasingly obstructed.
• Most cases are diagnosed on endoscopic examination at rest but in some partial cases a ‘dynamic’ endoscopic examination during exercise may be required to diagnose the condition because the larynx can appear relatively normal at rest but have abnormal function during strenuous exercise.

• A fluid present in the airways of horses affected by asthma (inflammatory airway disease) or respiratory infections (usually more yellow in colour and referred to as mucopus).
• The detection of mucus in the trachea of horse after racing by an endoscopic examination may be indicative an inflammatory condition in the lungs (asthma) that affected the racing performance of that horse.

• An official veterinary examination is a compulsory examination that may be ordered by the Stipendiary Stewards or the DVRWBP when a veterinary condition that may be of moderate to high significance for a horse’s future health, welfare or racing performance is detected.
• OVE requires that a horse is comprehensively assessed and appropriately managed the stable veterinary surgeon until it is considered by the trainer and the veterinary surgeon be in a suitable condition to return to racing. The horse will then be examined by a regulatory veterinary officer to confirm its suitability to return to racing.
• Generally the OVE will require that the horse perform a track gallop under the observation of a veterinary officer who will then examine after the gallop and decided upon its suitability to return to racing.

• OA is a degenerative condition of a joint usually caused by the wear and tear of training and racing. It affects all tissues of the joint including the cartilage and underlying bone, and the soft tissues of the joint (the synovial joint lining and the joint capsule).
• This is an irreversible condition (that’s why joint replacements are so widely used in humans) although early cases may be managed with careful use of medications and modified training.

A ‘chip’ of bone and cartilage (hence ‘osteochondral’) that has broken off within a joint, usually from its margin. Joints most commonly affected in race horses are the fetlock and the carpus (knee). Surgical removal of osteochondral fragments via keyhole arthroscopic surgery is often recommended.

An ongoing process of bone turnover, where bone tissue is removed and replaced with new bone in a process that takes around 3 months. The process of bone remodelling is suppressed during intense race training permitting microdamage to accumulate. Periods of rest from race training (for around 3 months) are needed to allow for the replacement of damaged bone with new bone.

• It develops when a structure (usually with reference to bone) is repeatedly loaded (over-stressed) by galloping over days, weeks and months and develops structural fatigue damage.
• If the horse is over-worked and is not provided with sufficient rest, structural fatigue damage (microscopic cracks in the bone) will accumulate and may cause local bone pain.
• Ongoing training and racing may result in stress fractures and even complete fractures that can be catastrophic.

Pain emanating from the front of the cannon bones, most commonly in the front limbs, and commonly occurring in horses in their first year of race training. Occasionally progresses to a stress fracture.

• The palate (hard and soft palate) separates the cavities of the mouth and nose. The soft palate is a flap of soft tissue that extends backwards into the horses' throat from the hard palate. Unlike many other animals including humans, horses are obligate nasal breathers (they must breathe through their noses). Normally, the soft palate forms an airtight seal that closes the mouth from the airway and allows a smooth flow of air into the lungs from the nose during breathing.
• In some horses, this seal may be ineffective and the soft palate may displace upwards from its normal position (termed Dorsal Displacement of the Soft Palate) and interfere with breathing.
• Jockeys often report that the horse slowed suddenly in running and made a gurgling noise or that the horse 'choked down' during the race. The problem can be frustrating to diagnose because the horse can re-position the soft palate by swallowing and often by the time the horse has returned after racing, everything appears in its normal anatomical position.
• The problem may be managed by the use of a tongue-tie and a cross over noseband. In cases that do not respond to conservative treatment, surgical correction may be attempted.

• A small incomplete fracture (an accumulation of micro fractures) in the bone that are caused by repetitive loading of galloping.
• Early recognition, accurate diagnosis and an appropriate period of rest is important so that a stress fracture does not progress to a complete catastrophic fracture.

• Racehorses are subject to intense physical stress during training and racing. Stress may cause immunosuppression and can cause horses to be more susceptible to infections. Often the signs of infection are mild and difficult to detect. Slight dullness, a minor increase in body temperature and a decreased appetite may give some indications of underlying illness. Blood tests can also prove useful in the detection of early infection.
• Although the signs are mild and affected horses may not appear to be obviously sick, the presence of an infection can have a significant effect on racing performance, where horses have to be in excellent health to perform competitively.
• Horses found to have subclinical infections will be treated by the stable veterinary surgeon and rested. A blood test to ensure that the horse has recovered will be required as part of the OVE.

• Ligaments are strong bands of tissue that bind bones together and stabilize joints.
• The suspensory ligament runs from the top of the back of the cannon bone over the back of the fetlock joint and inserts on the sesamoid bones before joining the extensor tendon towards the front of the pastern region.
• It is a very strong, relatively elastic structure that plays an important role in supporting the fetlock joint as it sinks to the ground when a horse's weight passes over the forelimb during motion. It is subject to tremendous forces during galloping, especially when the muscles fatigue.
• When injured, the suspensory ligament also heals with scar tissue and once damaged, it is prone to re-injury. Depending on the severity, suspensory ligament injuries may have severe consequences for a horse's future racing career. Seventy percent of all racetrack breakdown injuries are the result of failure of the suspensory apparatus (which comprises of the suspensory ligament, the sesamoid bones and other vital soft tissue structures in the limb).

• Tendons are strong cord like structures that transmit the pull created by a contracting muscle to bones to produce movement. They are composed of collagen and elastin fibres and are very strong, but have only limited elasticity or stretch.
• Tendons in the horses' legs are subject to tremendous forces. They have a relatively poor blood supply and when injured, heal very slowly by the formation of scar tissue. Scar tissue has virtually no elasticity. This means that an injured tendon is very prone to re-injury under the stresses of full training and racing.
• The tendons most commonly injured in the racehorse are the superficial digital flexor tendons (SDFT) of the forelimb. These tendons run down the back of each cannon and transmit the pull of the muscle behind the forearm to the bones of the foot.
• Getting a horse back to racing after a tendon injury requires a great deal of skill and hard work. Often a serious tendon injury will result in the retirement of a horse from racing.

Fluid filled structure surrounding some of the tendons in the limbs that lubricate the tendons and ease their passage around a bend in the limb.

The common throat conditions that may affect breathing during exercise and require surgical correction include laryngeal hemiplegia, Dorsal Displacement of the Soft Palate (DDSP) and epiglottic entrapment.

• These are surgical procedures performed on the throat to improve exercise tolerance in horses clinically affected by laryngeal hemiplegia (‘Roaring’).
• A laryngoplasty (Tieback) is performed under general anaesthesia and involves inserting a strong suture to permanently fix the paralysed arytenoid cartilage into an abducted (open) position.
• The Hobday procedure involves removal of the horse’s left vocal cord and the adjacent pocket of tissue (lateral ventricle) to decrease air turbulence in the airway and thereby reduce the abnormal respiratory noise.

• An unacceptable performance is a racing performance returned by a racehorse which is identified to be unsatisfactory and unacceptable by the Stipendiary Stewards.
• Generally a racing performance will be assessed as unacceptable when a horse finishes further than 20 lengths behind the winner of a race.
• Such performances may be caused by veterinary conditions and these horse must undergo a veterinary examination and assessment prior to returning to racing.