Equine Peripheral Neuropathy Study Guide

Overview and Clinical Importance

Peripheral neuropathies represent a significant category of neurological disease in horses frequently tested on the NAVLE. These conditions involve damage to peripheral nerves outside the CNS, resulting in motor dysfunction, sensory deficits, or both. The three most commonly tested peripheral neuropathies are facial nerve paralysis (CN VII), femoral nerve paralysis, and radial nerve paralysis.

Peripheral nerve injuries most commonly result from trauma, compression during recumbency (particularly during anesthesia), dystocia in foals, or secondary to systemic diseases such as equine protozoal myeloencephalitis (EPM). Nerve regeneration occurs at approximately 1 mm per day (roughly 1 inch per month).

Classification of Peripheral Nerve Injuries

The Seddon classification categorizes nerve injuries by severity: