When performing a lumbar puncture the needle stops before it pierces what space?

When performing a lumbar puncture, the needle typically stops before it pierces the dura mater, which is the tough outer layer surrounding the spinal cord. The goal is to reach the subarachnoid space, which lies beneath the arachnoid mater and contains cerebrospinal fluid. Care is taken to avoid damaging the dura and the underlying tissue, ensuring a safe procedure. Proper technique and anatomical knowledge are essential to successfully navigate to the subarachnoid space.