Acute Nerve Injury

Excerpt

Historically, our knowledge of peripheral nerves and peripheral nerve injuries (PNIs) came mainly from experiences on the battlefield. Sir Herbert Seddon published his PNI classification system while caring for the injured during the second world war (1942). Nevertheless, in modern times, it is not uncommon to encounter PNI in non-combat-related trauma cases. These injuries can be life-changing and are often associated with significant morbidity, potentially leading to significant disabilities. Given that they mostly present in young adults of working age, these disabilities carry lifelong implications for the patients.

Peripheral nerve trunks are composed of three separate layers surrounding nerve fibers. The innermost collagenous endoneurium layer envelops the axonal fibers (myelinated or unmyelinated) to provide mechanical and metabolic support. Together they make up the nerve fascicles, each of which is surrounded by a flattened cellular layer called the perineurium. The outer most collagenous layer, called the epineurium, surrounds the fascicles. Knowledge of this anatomy is essential for comprehending the classifications, clinical findings, and prognosis of PNIs and, thus, the best possible management for each patient.