Introduction

• Chronic painful foot conditions that do not respond to other therapies may respond to permanent relief of pain by sectioning of the nerve supplying affected region.

Uses

• Navicular bone fracture   Navicular bone: fracture  :
  • For horses intended for return to athletic activity, where there is residual lameness after prolonged rest, or after a short rest when prolonged rest period is not possible.
• Navicular disease   Navicular bone: syndrome  .
• Fractures of the palmar process of the distal phalanx .
  Contraindications
• Navicular bones that are excessively osteoporotic with large medullary cyst formation - neurectomies in horses with these may lead to catastrophic failure of the limb with strenuous use.

Advantages

• Simple surgical procedure.
  Alternative techniques
• Epineural capping.
• Cryoneurectomy.
• Electrocoagulation.
• Transection.
• Combination of techniques.

Disadvantages

• Of no benefit if source of pain involves the dorsal half of the distal digit or does not respond to palmar digital perineural anesthesia   Forelimb: perineural analgesia    Hindlimb: perineural analgesia  .
• A variety of techniques have been described, all associated with some complications.
• Permanent loss of sensation to the foot could result in inadvertant self trauma.

Requirements

Preparation

Procedure

Aftercare

Outcomes

Prognosis

• In many cases re-innervation occurs within two years.
• Good: if source of lameness innervated by palmar digital nerve, but long term problems likely.
• Poor: guarded - if deep digital flexor tendon ruptures - salvage only.

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Murray R C et al (1994) Acute effects of perineural administration of sodium hyaluronate on palmar digital neurectomy sites in horses. Am J Vet Res 55 (10), 1484-1489 PubMed.
• Jackman B R et al (1993) Palmar digital neurectomy in horses. 57 cases (1984-1990). Vet Surg 22 (4), 285-288 PubMed.
• Cummings J F et al (1988) Attempts to prevent equine post neurectomy neuroma formation through retrograde transport of two neurotoxins, doxorubicin and ricin. Equine Vet J 20 (6), 451-456 PubMed.
• Fubini S L et al (1988) The use of intraneural doxorubicin in association with palmar digital neurectomy in 28 horses. Vet Surg 17 (6), 346-349 PubMed.
• Said A H et al (1984) Clinicopathologic studies on neurectomy in equids. Equine Vet J 16 (5), 442-446 PubMed.

Other sources of information

• Yovich J V (1982) Palmar digital neurectomy. In: Equine Surgery. Ed: J A Auer. W B Saunders, USA. ISBN 0-397-50937-5.