lumbar and sacral

Last reviewed 01/2018

The motor and reflex abnormalities secondary to cord compression depend on the level of the lesion:

T12-L1:

  • loss of cremasteric reflex
  • normal abdominal reflexes
  • upper motor neurone signs in the lower limbs

L3-L4 lesion:

  • lower motor neurone signs in quadriceps and hip adductors
  • normal hip flexion
  • absent knee jerk
  • ankle reflexes variable - reflex may be increased and a Babinski response elicited; however if the whole conus is involved then there is a lower motor neurone lesion

S1-S2 lesion:

  • lower motor neurone weakness in hip extension and and knee flexion; also in calf and foot muscles
  • knee jerks are normal
  • absent ankle reflexes
  • plantars are down going
  • anal reflex is normal

S3-S4 lesion:

  • loss of anal reflex
  • sensory loss - saddle area
  • lower limbs are normal