A spinal headache, also known as a postdural puncture headache, is a complication of needle insertion into the subarachnoid space through the dural sac. The dural sac encases the spinal cord and cerebrospinal fluid.This is a pressurized system that extends from the intracranial cavity down to the sacrum. Fluctuation in pressure can result in headache. This commonly occurs after diagnostic lumbar puncture. It is a less common complication of spinal anesthesia and spinal interventional pain injections.