Spinal and nerve lesions

Key points

Spinal conus level:

Neonate - L2/3

Older - L1

Erbs palsy

Injury to C5 and C6 nerve roots (also C7 in 50%)

'Waiter's tip hand' - internal rotation of the forearm, flexion of the wrist and fingers

C3 and C4 injuries in 5% of patients, leading to phrenic nerve dysfunction and paralysis of the hemidiaphragm

Stellate ganglion disruption in 5% - leads to Horners syndrome

Klumpke’s palsy

C8 + T1 injury

Rare

Claw hand

Clawing less evident in proximal ulnar nerve lesions (Ulnar paradox)

Weakness in flexor digitorum profundus (FDP) tendons reduces ring and small finger flexion

Spinal cord injury

Complete transection/myelitis

?LMN at level of lesion, UMN below

Brown sequard - Ipsilateral loss paralysis and loss of proprioception. Contralateral loss of pain and temp (Spinothalamic tract crosses over)

Anterior cord syndrome - flexion injury - loss of motor, pain and temp. Preservation of vibration + proprioception (posterior columns)

Posterior cord - opposite

Cauda equina

Below L2

References

Chater M, Camfield P, Camfield C. Erb's palsy - Who is to blame and what will happen? Paediatr Child Health. 2004 Oct;9(8):556-560. doi: 10.1093/pch/9.8.556. PMID: 19680484; PMCID: PMC2724163.