LE weakness

Know where spinal cord ends, and the location of spinal nerve root exiting the spinal cord.

Appreciate Lesion at T4 vertebrae, nerve damage is likely T5 spinal cord, and even T6

http://www.neuroanatomy.wisc.edu/coursebook/clinicalspinal.pdf

Appreciate anterior division and posterior division of nerve

Know how Lumbar plexus is formed.

Know how Sacral Plexus is formed.

Know how Coccygeal Plexus is formed.

Know the following are the nerve exiting the pelvic bone down in to the legs

Lateral Cutaneous Nerve of Thigh L2, L3
Sciatic Nerve

Common fibular (Peroneal Nerve) (Posterior Division)
Tibial Nerve (Anterior Division)

Posterior cutaneous nerve of thigh
Femoral Nerve

http://www.backpain-guide.com/Chapter_Fig_folders/Ch05_Anatomy_Folder/10LSPlex.html

Appreciate a location to examine for LE sensory examination corresponding to the dermatomes

L1, L2, L3, L4, L5, S1, S2, S4, S4
Appreciate the location of S3, S4, S5 sensory distribution

International standards for neurological classification of spinal cord injury (Revised 2011)

Appreciate that radiculopathy involving L3, L4, L5 and S1 will have different extent of radiation based on the dermatomal distribution of corresponding nerve

S1 radiculopathy will radiate all the way down but is more POSTERIOR and PLANTAR Surface of the feet
L5 radiculopathy will radiate all the way down but is more ANTEROLATERAL LEG and DORSUM of the feet
L4 is anterior leg but crosses knee (DOES NOT go to the feet(
L3 is anteromedial of the thigh (does not cross the knee)

CONTRAST THIS TO SCIATIC Nerve involvement in any position, where pain will radiate all the way down as it has S1 nerve root. Please see the diagram of the lumbosacral plexus

http://www.neuroanatomy.wisc.edu/coursebook/clinicalspinal.pdf

Appreciate the involvement of Sacral Nerve root in Cauda Equina and how it will not have sensory or motor loss of the LE.

Appreciate only area involved is S2, S3, S4 in the perineum

http://www.neuroanatomy.wisc.edu/coursebook/clinicalspinal.pdf

Appreciate the various location of Nerve Injury and the Mechanism Involved. Few that are worth noting are.

Appreciate how L4-L5 Disc Herniation affects L5 nerve root
Appreciate how annulus fibrosis tear leads to disk herniation by herniation of the nucleus pulposus

C: Spondylolistheis i.e anterior slippage of lumbar vertebrae leads to stretch of nerve roots
D: Appreciate foramina stenosis due to Apophyseal joint hypertrophy and Ligamentous Hypertrophy
E: Appreciate Synovial cyst from apophygeal joint degeneration that causes spinal stenosis