Anaesthesia While performing a lumbar puncture, a snap is felt just before entering into the epidural space. This is due to piercing of which structure? A Ligamentum flavum B Supraspinous ligament C Duramater D Posterior longitudinal ligament 💡 Explanation While performing a lumbar puncture, a snap is felt just before entering into the epidural space. This is due to piercing of which structure? ✓ Correct Answer: A. Ligamentum flavum