The L level simply describes the anatomical location where a lumbar sympathectomy procedure is done. For example, if the titanium clips are applied at the L3 level it means that the clips were applied at the level of the third lumbar vertebra.
We human beings have 5 lumbar vertebrae. In the thoracic region (for hand sweating), we have 12 vertebrae. Those levels are used in order to establish a unified approach as to the best level for the sympathectomy.
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