Similar. Both are neuraxial blocks that prevent nerve transmission. The space that the spinal goes is placed in is adjacent to the epidural space. It is typically a single shot that wears off in a predetermined time. A small catheter can be placed in the epidural space and allow for a variable length of activity. That is why epidurals are more useful for labor. The needles are also a little different.
No. While they may feel the same to you, they are a little different. An epidural puts continuous medication in a sac around the spinal cord, providing longer, lower level numbness. Spinals put the medication in the fluid directly around the spinal cord just once. Epidurals numb a little less but longer, spinals numb a lot but only last a shorter period of time.
They are different. Spinal and epidural injections share many characteristics. But, the spinal needle is inserted a few mm deeper than the epidural needle so that it punctures the dura (one of the membranes that cover the spinal cord) and rests in cerebrospinal fluid (csf). Local anesthetic injected in the CSF produces a fast, dense nerve block that numbs all the way to the toes.