Palmar digital nerve: neurectomy

• 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.

Alternative techniques

• Definitive diagnosis of source of lameness should be obtained - full lameness workup including diagnostic imaging:
  • Examination of horse at rest   Musculoskeletal: physical examination - adult  .
  • Gait evaluation   Musculoskeletal: gait evaluation  .
  • Perineural analgesia, forelimb   Forelimb: perineural analgesia  .
  • Radiography forelimb   Forelimb: radiography  .
• Response to palmar digital nerve block   Forelimb: perineural analgesia  essential before considering neurectomy   Palmar digital nerve: neurectomy  .
• Try conservative or other therapies before undertaking neurectomy   Palmar digital nerve: neurectomy  .
  Check legality of procedure with relevant legislature