2. Nerve Compression Patterns Flashcards
CNS
Spinal cord ad interneurons
PNS
1a afferent and alpha motor neurons
ALS
cell bodies of alpha and gamma motor neurons die as well as cells in the corticospinal tract: PNS and CNS
Compression of distal median nerve
Sensory symptoms first
then Motor
LMN signs & symptoms
Atrophy Weakness or paralysis Hypotonic DTRs Decreased muscle tone Fasciculations
In peripheral nerve distribution
UMN signs & symptoms
Spasticity Hypertonic or hypotonic DTRs Clonus \+ Babinski or Hoffman’s reflexes Weakness Synergistic movement patterns
Usually affects one or both sides of the body
Fasciculations
Rapid, fine, painless or painful contraction of groups of muscle fibers (often LMN sign)
Visible but not strong enough to move limbs
Commonly seen in anterior horn cell disorders (e.g. ALS)
Fasciculation v Fibrillation
Fasciculation are most often painful
Fibrillations can ONLY be seen with needle EMG
UMN – Brain
Motor loss of a body part
Sensory loss of a body part
“Glove-like or sock-like”
Reflexes: hypo or hypertonic
UMN – Spinal Cord
Motor loss: Myotome or loss below level of injury
Sensory loss: Dermatome or loss below level of injury
Reflexes: hypo or hypertonic
LMN – Nerve Root
Motor loss: myotome
Sensory loss: dermatome
Reflexes hypotonic
Discovering losses
sensation –> pain sensation –> motor
LMN – Peripheral Nerve
Motor loss: nerve distribution
Sensory loss: nerve distribution
Reflexes hypotonic
Peripheral nerve compression somewhere after the plexi (after the peripheral nerves have been formed)
Perform sensory & motor examination to determine which nerve has an compression site (and where)
UE PND Radial nerve (C6-8, T1)
Motor: Elbow extension, Wrist and finger extension, Supination
Sensory in radial distribution
Upper Extremity Peripheral Nerve Distributions Median Nerve (C6-8, T1)
Motor: Pronation, Wrist flexion, and Long finger flexors
Sensory in median distribution
