Neurectomy of limbs in equine

Neurectomy of limbs in equine by Sabal Pokharel.

1. NEURECTOMY OF LIMBS IN EQUINE PRESENTER Sabal Pokharel Enrolling BVSC&AH

2. NEURECTOMY A neurectomy is a type of nerve block involving the severing or removal of a nerve. Neurectomy (palmar digital neurectomy ) is a surgical procedure in which a portion of the nerve supply to the foot of the horse is cut or removed for the treatment of heel pain or navicular disease. This surgery is performed in rare cases of severe chronic pain where no other treatments have been successful.

3. NEURECTOMY Currently , neurectomy is recommended only as a last resort when other treatment options have been performed, the horse has become refractory to other treatments and a soft-tissue injury has not been found on an MRI. If the lameness does not localize to the heels, then a neurectomy procedure will not be successful and the horse may remain lame.

4. INDICATIONS OF NEURECTOMY I. Splints : Splints is allignment characterized by a hard, bony swelling, usually on the inside of a front leg, lying between the splint and cannon bone or on the splint bone itself .

5. INDICATIONS OF NEURECTOMY II. Navicular Disease : The result is the inflammation or degeneration of the navicular bone and its surrounding tissues, typically in the front feet of the horse. This disease can lead to significant or disabling lameness of a horse .

6. INDICATIONS OF NEURECTOMY III. Ring Bone : Ringbone in horses refers to a painful condition characterized by new bone growth. It affects either the pastern joint or the coffin joint.

7. NEURECTOMY OF LIMBS The term palmer refers to palm of Hand. Palm of forelimb is called Volar Palm of hindlimb is called planter.

8. ANAESTHESIA Local Anesthetics 2% Procaine, 2-4 ml. Injected perineurally . Needle : 25 gauge Site of Injection Palpate lateral and medial palmer neurovascular bundles. Place needle axial to collateral cartilage as low in foot as possible. Can also be performed with limbs held up or horse standing on nerve too.

9. ANAESTHESIA Blocks the palmer region of foot and sole. Navicular bone Navicular bursa Digital Cushion Sole , Heels Coffin Joint.

10. MEDIAL PALMAR NERVE LATERAL PALMAR NERVE

11. Site of anesthesia

12. SURGICAL TECHNIQUE Make a vertical incision about an inch long along the length passing through the skin, subcutaneous fascia and deep fascia. The edges are separated and depth is palpated with fingers to identify the cord of vessels and then they are raised on tenaculum . If the structures are not immediately apparent then support and pressure from the under surface of leg may push them into view. The nerve is identified by yellow colour and longitudinal striations and about an inch is removed and wound is sutured

13. SURGICAL TECHNIQUE Differentiating nerve from vein and blood vessel should be done. A vein has bluish or purple colour whereas blood vessel will appear pale at that spot after raising with tenaculum due to displacement of blood. The palmar digital nerve is first divided proximally and then distally. The skin wound is closed by interrupted appositional suture.

14. COMPLICATIONS OF SURGERY Complications of this neurectomy can include the following. F ormation of a painful neuroma, or ball of nerves at the surgery site . Sloughing of the foot. L uxation of the coffin joint. R upture of the deep digital flexor tendon. It can occur if the lameness has not been properly localized to the navicular bone alone. The procedure is also not permanent as the nerves can grow back and the disease process that caused the lameness still continues. Horses that have a neurectomy procedure need to be observed carefully as they will lose sensation in the heels. So if they step on a nail, for instance, they will not feel the foreign object in the foot.

15. END