Peripheral nerve injury

Question 1

Definition

Answer 1

PNS disorder

caused by interruption of peripheral nerves due to compression, traction or transection

resulting in ipsilateral sensory and motor impairments

Question 2

Cause

Answer 2

Atraumatic

• PNS disorder
• Virus

Traumatic

• Fracture: nerve compression, traction
• Transection
• Cranial nerve

Question 3

How is it diagnosed

Answer 3

Clinical assessment: motor (strength, muscle tone, reflexes) and sensory (DCS, ALS) + nerve conduction study (EMG)

Question 4

Problems (presentation)

Answer 4

Ipsilateral presentation

Sensory

• somatosensation:
  
  • DCS: Light touch, proprioception
  • ALS: pin prick, temperature

Motor

• paresis
• abnormal muscle tone: hypotonia
• abnormal muscle stretch reflex: hyporeflexia

Question 5

Management

Answer 5

Conservative or Surgical

Question 6

Neurons affected

Answer 6

Primary afferent neurons (sensory)

Lower motor neurons (motor)