User:Danika paulo/Neurapraxia Proposal

Intro: What is it?

temporary failure of nerve conduction in the absence of structural changes, due to blunt injury, compression, or ischemia

Focal Conduction Block

Transient

Ischemic

affects mainly large-caliber axons

More persistent

demyelinating

attributable to an underlying primary/segmental demyelination

axonal constriction

injury to a nerve resulting in paralysis without degeneration and followed by rapid and complete recovery of function
partial or complete conduction block over a segment of a nerve fiber, with temporary paralysis
nerve condition characterized by localized loss of conduction that causes short-term paralysis, there is no degeneration of the axon and complete recovery is usual

Causes of Neuropraxia

focal blocking of impulse conduction usually due to compression

compression:

exogenous pressure affecting a peripheral nerve causes decreased blood flow and structural deformation of nerve fibers

conduction study

waveform, amplitude, duration

latency and conduction velocity

types of abnormalities

reference: Peripheral Neuropathy 4th edition, 2005

Diagnosis of Neurapraxia

The most commonly described mechanism of injury is axial compression with a component of either hyperflexion or hyperextension
early signs of nerve injury include:

disturbance of sensation, weakness or paralysis of muscle, vasomotor and sudomotor paralysis in distribution of the affected nerve or nerves, abnormal sensitivity of nerve at point of injury

Neurapraxia has been reported in association with developmental cervical spinal stenosis, kyphosis, congenital fusions (Klippel-Feil syndrome), cervical instability (traumatic or developmental), and invertebral disc herniation.

Symptoms of Neurapraxia

large myelinated fibers more susceptible than small or unmyelinated ones

as result predominant symptoms:

loss of muscle strength

loss of touch sensation

disturbance of function can last from hrs to weeks only rarely months

An episode of cervical cord neurapraxia generally resolves in less than 10-15 minutes.

Treatments for Neurapraxia

prognosis for complete recover is good
peripheral neurons are large, spatially complex cells whose size and connectivity compromise their capacity to repair

reference: Peripheral Neuropathy 4th edition, 2005

Studies have shown that 56% of athletes returning to contact sports experienced a recurrent episode of transient cervical cord neurapraxia.

This number was higher when an athlete returned to football versus another sport

Experimental Case/Research Study on Neuropraxia

Neurapraxia of the cervical spinal cord with transient quadriplegia

JS Torg, H Pavlov, SE Genuario, B Sennett, RJ Wisneski, BH Robie and C Jahre J Bone Joint Surg Am. 1986;68:1354-1370.

Cervical cord neurapraxia – An acute transient episode of bilateral sensory and motor abnormalities.