This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neuroanatomy, Subject name: Anatomy
Subarachnoid space extends up to: 
Select and explain. 
A. Lower border L1, B. Upper border L1, C. Upper border of S2, D. Lower border of S2
D: Lower border of S2
Answer: D: Lower border of S2 
Explanation: 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.