Best site for going spinal anaesthesia is interveebral space between.

The spinal canal contains the spinal cord with its covering (the meninges), fatty tissue and venous plexus. The meninges are composed of three layers: the pia mater, the arachnoid mater and the Dura meter. The spinal subdural space is poorly demarcated. The epidural space is a better defined potential space within the spinal canal that is bounded by the Dura meter and ligamentum flavum. There is cerebrospinal fluid between pia meter and Archnoid meter and this space is called sub arachnoid space. The spinal cord normally extends from the foramen magnum to the level of L1 in adults. so in adults we can give spinal anesthesia below this level in L2/L3, L3/L4. L2/L3 IS BETTER SPACE In children the spinal cord ends at L3 and moves up with age. The blood supply to the spinal cord and nerve roots is derived from a single anterior spinal aery and pair posterior aeries.