Anatomy of the lumbar spine area
February 25, 2016 | 15,00 EUR | answered by Dr. med. Ralf Berg
Hello Dr. Berg, I am here again, I asked some questions about high SPA here a few months ago.
Now I have another concern. It is about the anatomy in the lumbar spine area.
Can you tell me what the normal usual distances are in the lumbar spine area of an adult?
Just approximately, not in millimeters.
a) Spinous process of the lumbar vertebra to the skin?
b) Transverse process to the skin? Is there even a transverse process in the lumbar spine area? Or only in the cervical spine area?
The background is that I suffered from delayed puberty for a long time, did not fully mature, and in the months in question it was questioned whether I should have been allowed to receive epidural anesthesia safely at all.
a) Do my measurements correspond to those of an adult?
a) Distance from the spinous process of the lumbar vertebra to the skin was 8 mm.
b) Distance from the transverse process to the skin was 4.9 cm.
In your opinion, is it safe to place an epidural catheter here? Or are these normal anatomical values.
Greetings, thank you!
Hello,
I am happy to answer your questions. The distance from the skin surface to the spinous process essentially depends on the thickness of the subcutaneous fat layer, and secondly on the position of the entire lumbar spine. In slim individuals, the measurement you obtained is normal.
During strong flexion of the spine, even in obese individuals, the spinous process presses against the skin, causing the distance to decrease from several centimeters to a few millimeters.
There is also a transverse process in the lumbar spine area, which lies about 2-6cm deeper from the skin surface. So, your measurements are also within the normal range here.
When placing an epidural catheter, there are basically two access points:
1. The central dorsal access, where the transverse process distances do not matter.
2. The lateral access from left or right. Since the needles used are all 10-14 cm long, a puncture should also be possible for you there.
To determine if normal conditions exist in your case, it is best to clarify with an overview image of the lumbar spine. Since this examination can burden the unborn child during pregnancy, it should only be considered in cases of urgent necessity.
If the clinic, i.e. the physical examination, does not show any abnormalities, an attempt at puncture without prior X-ray is appropriate.
Pubertas tarda usually does not have a primary deforming effect on the spinal column; rather, the development and ossification, as well as closure of growth plates, are delayed. In my opinion, this should not affect the puncture.
In conclusion, placing an epidural catheter is generally safe, but even with normal anatomy, there is no guarantee that complications will not occur.
Best regards,
Dr. R. Berg
