Surgery While doing a lumbar puncture in an infant you choose a lower inter-veebral space than in an adult. Choose the TRUE reason. A The spinal cord extends up to lower border of L1 in an adult B The spinal cord extends up to the lower border of L3 in an infant C The spinal cord extends up to the upper border of L3 in an infant D The spinal cord extends up to the upper border of L2 in an infant 💡 Explanation While doing a lumbar puncture in an infant you choose a lower inter-veebral space than in an adult. Choose the TRUE reason. ✓ Correct Answer: C. The spinal cord extends up to the upper border of L3 in an infant