Anaes SAQs · Applied anatomy
Vertebral column and neuraxial spaces
Primary — vertebral column (33 vertebrae, curvatures, typical vertebra); spinal cord termination at L1/L2 (conus) and cauda equina (neonate L3); meninges (dura, arachnoid, pia) and the subarachnoid (CSF) and subdural spaces; epidural space contents (fat, Batson venous plexus, nerve roots); ligamentum flavum and loss of resistance; needle path (skin, subcutaneous, supraspinous, interspinous, ligamentum flavum, dura, arachnoid, subarachnoid); Tuffier's line at L4; paediatric lower interspace.
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Question
Describe the anatomy of the vertebral column and the meninges relevant to neuraxial anaesthesia. List the layers a midline needle passes through to reach the subarachnoid space, and explain how you choose a safe interspace. (Question stem restated — the worked answers below carry the primary-source citations.)
References4ShowHide
- [1]Alsaati I, et al. MRI-based lumbar epidural-space depth. Tomography, 2026.PMID 42042941
- [3]Alessi L, et al. Anesthetic Management in a Patient With Tethered Spinal Cord Syndrome Undergoing Knee Replacement Surgery. Case Rep Anesthesiol, 2026.PMID 42339046
- [4]Goksu H, et al. Evaluation of loss of resistance technique using an air-filled injector to enhance accuracy of landmark-guided knee joint injections. Turk J Phys Med Rehabil, 2026.PMID 42291381
- [5]Greenspon NH, et al. Pneumorrhachis After Inadvertent Dural Puncture as a Cause of Severe Neck Pain Limiting Labor Participation and Necessitating Operative Vaginal Delivery: A Case Report. A&A Pract, 2026.PMID 42257607