Page 332 - The Veterinary Care of the Horse

Proximal suspensory desmitis of the hind limb

This injury can occur in any type of horse but is commonly seen in dressage horses. Poor
VetBooks.ir conformation may be a contributory factor. Horses with straight hocks, abnormally sloping

pasterns and long-toe, low-heel conformation are at risk.

CLINICAL SIGNS

• Lameness, which can be mild to severe, with a sudden or gradual onset. The horse may

adopt a shorter hind limb stride with a low foot flight arc and scuffing of the toes. The
lameness occurs as a result of compression of the deep branch of the lateral plantar nerve
when the ligament swells within the confined space between the cannon bone and the

two splint bones, leading to persistent pain and lameness. Flexion of the limb may
accentuate the lameness as may working on a circle. The lameness may be more obvious

when the horse is ridden with affected horses showing reduced hind limb impulsion and
reluctance to go forwards.

• Heat and swelling may be present but this is not a consistent sign.

• Deep palpation of the origin of the ligament may be painful.

DIAGNOSIS

Diagnostic techniques are as for the forelimb, i.e:

• nerve blocks

• ultrasonography

• radiography: as these lesions are often chronic by the time the cause of lameness is
diagnosed, radiographic changes of the proximal cannon bone are more commonly seen
than in the forelimb

• scintigraphy

• Magnetic Resonance Imaging (MRI)

• Computed Tomography (CT).

Very often a combination of the above techniques is required for diagnosis of this condition.

TREATMENT

Treatments include:
• box or small paddock rest

• non-steroidal anti-inflammatory drugs, e.g. phenylbutazone, may be prescribed in the