Question: Where does the needle go for a spinal tap?

Disambiguated questions and answers:
context: The spine of an infant at the time of birth differs from the adult spine. The "conus medullaris" (bottom of the spinal cord) terminates at the level of L1 in adults, but may range in term neonates (newly born babies) from L1-L3 levels. It is important to insert the spinal needle below the conus medullaris at the L3/L4 or L4/L5 interspinous levels. With growth of the spine, the conus typically reaches the adult level (L1) by 2 years of age.
question: Where does the needle go for a spinal tap in a newly born baby?
short_answers: below the conus medullaris at L3/L4 or L4/L5 interspinous levels
wikipage: Lumbar puncture
context: The person is usually placed on their side (left more commonly than right). The patient bends the neck so the chin is close to the chest, hunches the back, and brings knees toward the chest. This approximates a fetal position as much as possible. Patients may also sit on a stool and bend their head and shoulders forward. The area around the lower back is prepared using aseptic technique. Once the appropriate location is palpated, local anaesthetic is infiltrated under the skin and then injected along the intended path of the spinal needle. A spinal needle is inserted between the lumbar vertebrae L3/L4, L4/L5 or L5/S1 and pushed in until there is a "give" as it enters the lumbar cistern wherein the ligamentum flavum is housed. The needle is again pushed until there is a second 'give' that indicates the needle is now past the dura mater. The arachnoid membrane and the dura mater exist in flush contact with one another in the living person's spine due to fluid pressure from CSF in the subarachnoid space pushing the arachnoid membrane out towards the dura. Therefore, once the needle has pierced the dura mater it has also traversed the thinner arachnoid membrane. The needle is then in the subarachnoid space. The stylet from the spinal needle is then withdrawn and drops of cerebrospinal fluid are collected. The opening pressure of the cerebrospinal fluid may be taken during this collection by using a simple column manometer. The procedure is ended by withdrawing the needle while placing pressure on the puncture site. The spinal level is so selected to avoid spinal injuries. In the past, the patient would lie on their back for at least six hours and be monitored for signs of neurological problems. There is no scientific evidence that this provides any benefit. The technique described is almost identical to that used in spinal anesthesia, except that spinal anesthesia is more often done with the patient in a seated position.
question: Where does the needle go for a spinal tap in an adult?
short_answers: between the lumbar vertebrae L3/L4, L4/L5 or L5/S1
wikipage: Lumbar puncture

Long-form answers:
knowledge: content: The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis.
wikipage: Lumbar vertebrae
content: They are designated L1 to L5, starting at the top.
wikipage: Lumbar vertebrae
content: The sacrum (plural: sacra or sacrums[1]), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1–S5) between ages 18 and 30.
wikipage: Sacrum
long_answer: Where the needle goes for a spinal tap is different for newly born babies and adults. In an adult, it goes between the lumbar vertebrae L3/L4, L4/L5 or L5/S1, with the five lumbar vertebrae designated L1 to L5, starting at the top, and the sacral vertebrae, S1 to S5, at the base of the spine. In a newly born baby, it goes below the conus medullaris at L3/L4 or L4/L5 interspinous levels.