Subarachnoid space extends up to:
Ans. D Lower border of S2Ref: Netter's Clinical Anatomy, 3rd ed. pg. 420* The subarachnoid space extends up to lower border of S2 where the dura fuses with filum terminale and obliterates the subarachnoid space.* The spinal cord extends from upper border of atlas to lower border of L1 or upper border of L2. The spinal cord ends in a sharp tip called conus medullaris.* The conus is continuous with filum terminale, which is a fine connective tissue element which descends up to the dorsum of the first coccygeal ligament.
Neuroanatomy
Lower border L1
Upper border L1
Upper border of S2
Lower border of S2
Lower border of S2