Page 289 - The Veterinary Care of the Horse

These techniques are reserved for horses that fail to respond to management changes and

medication.
VetBooks.ir NAVICULAR SUSPENSORY DESMOTOMY

In this operation the collateral suspensory ligaments are cut under general anaesthesia. In one

study, 76% of horses were sound after 6 months and 43% remained sound after 3 years.
Another study reported only a 6–12 month period of soundness.

PALMAR DIGITAL NEURECTOMY

If the horse becomes completely sound with a palmar digital nerve block that desensitizes the

back of the foot and the sole, it may be a suitable candidate for neurectomy. With the horse
under general anaesthesia, a section of the palmar digital nerve is removed. Approximately

74% of horses in one study were reported to be sound after 1 year, reducing to 63% after 2
years. Many horses remain sound for 12–18 months. This procedure must be combined with

excellent ongoing foot care and is only used as a last resort.
Complications of the procedure include:

• persistent lameness

• recurrence of lameness due to re-innervation of the navicular bone; the surgery can be
repeated but may not be as successful the second time

• formation of a painful swelling (neuroma) at the cut end of the nerve

• rupture of the DDFT; the operation should not be performed on horses with obvious
defects on the flexor surface of the navicular bone as the DDFT is likely to have

significant lesions
• with continued use of the horse, the weakened navicular bone may fracture

• penetrating injuries to the sole and foot abscesses may go unnoticed as the sole also loses

sensation with this procedure.
• horses are not allowed to complete in FEI competitions after a neurectomy.

Prognosis

There is no cure for navicular syndrome and the disease is progressive. The outlook is always

guarded, especially for performance animals.

FRACTURE OF THE PEDAL BONE