Types of swelling

■ CELLULITIS

Cellulitis, also called septic cellulitis, is a bacterial infection of the deeper layers of the skin. It can occur anywhere on the body, but in horses the infection commonly occurs in one of the hind legs. Cellulitis typically starts with sudden swelling that is warm and painful to the touch. Veterinary attention is required.

■ LYMPHANGITIS

Lymphangitis is inflammation of the lymph vessels most usually in the limbs and typically appears as a hot, painful, extremely swollen limb, usually the hindleg. Severe lymphangitis can be difficult to treat and requires veterinary attention.

■ OEDEMA

Oedema is an accumulation of lymphatic fluid under the skin that has settled to the lowest point of the body. They are usually painless and will disappear with increased circulation of the lymphatic system.

■ TENDON, LIGAMENT AND JOINT INJURIES

Sprains and strains involving tendons, ligaments or a joint capsule will often produce inflammation, pain, swelling and lameness, and require immediate veterinary attention.

■ WINDGALLS

These are residual inflammations from old tendon and ligament injuries. They usually occur on the back of the leg, at or just above fetlock level. Windgalls normally occur on both hind legs, although they occasionally appear on just one leg and sometimes can also be found in the front legs. They are usually painless and will often disappear during exercise and movement.

■ ABSCESSES

Foot abscesses are associated with sudden onset severe lameness, and often cause legs to fill due to the inflammatory processes occurring in the foot. Your vet and/or farrier should be called out to locate and release the infection from the abscess, after which the foot should be poulticed to draw out any remaining infection.

■ FILLED LEGS

Filled legs is the term used to describe a condition in which the length of a horse’s legs (more commonly the hind pair) appear swollen. It’s often the result of the horse standing in his stable for longer than normal and not doing enough exercise. Once the horse has started moving, the swelling often dissipates.

■ DEGENERATIVE JOINT DISEASE

Degenerative joint disease (DJD) is the most common type of arthritis in horses. It is a chronic disease in which the cartilage on the ends of bones wears down, resulting in loss of joint mobility, swelling, heat and pain.

■ ARTHRITIS

Arthritis is very common in horses, especially in the ageing population. It is a degenerative joint disease that causes pain and inflammation. Over time, the inflammation damages the cartilage within a joint beyond repair, leading to chronic pain.