<P> In humans , the spinal cord stops growing in infancy and the end of the spinal cord is about the level of the third lumbar vertebra , or L3 , at birth . Because the bones of the vertebral column continue to grow , by about 12 months of age , the end of the cord reaches its permanent position at the level of L1 or L2 ( closer to the head ) . However , due to normal anatomical variations , the final cord end position may occur anywhere from T12 twelfth thoracic vertebra ( T12 ) to L3 . Individual spinal nerve roots arise from the cord as they get closer to the head , but as the differential growth occurs , the top end of the nerve stays attached to the spinal cord while the lower end of the nerve exits the spinal column at its proper level . This results in a `` bundle '' - like structure of nerve fibers that extends caudally from the end of the spinal cord , gradually declining in number further down as individual pairs leave the spinal column . </P>
where does the spinal cord become cauda equina
L1 or L2