Page 377 - The Veterinary Care of the Horse

• narrowing or disappearance of the joint space

• subchondral bone sclerosis.
VetBooks.ir In some cases where radiographic changes are not visible, the diagnosis may be confirmed by

scintigraphy.

TREATMENT

Once osteoarthritis has developed, the treatment options are limited. They include:

• rest in the early stages of disease
• trimming the foot to correct any foot imbalance and shortening the toe

• shoeing with squared or rolled-toe shoes to ease breakover

• non-steroidal anti-inflammatory drugs, e.g. phenylbutazone, which may allow the horse

to continue in work
• intra-articular injections of corticosteroid and hyaluronan

• oral administration of nutraceuticals eg glucosamine and chondroitin sulphate

• intravenous hyaluronan or intramuscular glycosaminoglycan or pentosan polysulfate

• surgical arthrodesis (where the joints are fused surgically) is an option for consideration
in some horses

• Chemical fusion of the joint has been successfully achieved with intra-articular injections

of ethyl alcohol. A minimum of 2–3 injections is usually required.

PROGNOSIS

The prognosis for horses with osteoarthritis of the PIP joint is guarded. It is more favourable

in cases involving a hind limb.

OSTEOCHONDROSIS (OCD)

Osteochondrosis is disease that causes localized abnormalities in the cartilage and bone of

young growing animals. As the skeleton grows, cartilage is converted to bone by a process
known as endochondral ossification. In affected animals, this process is interrupted leaving
thickened areas of cartilage on the joint surface which extend into weakened underlying

(subchondral) bone. These areas are very prone to injury and fissures develop in the cartilage
and lead to inflammation of the joint. Small pieces of cartilage may become detached and

move around within the joint. When a flap of articular cartilage lifts away from the joint