Assertion: lumbar plexus | /r/MadeOf | ventral branches of the first
Facets:
value: to the fourth upper lumbar nerves
type: OTHER
Source sentences:
text: It is formed by the ventral branches of the first to the fourth upper lumbar nerves (L1-L4), with the last thoracic nerve (or T12) usually supplementing the first lumbar level by a small branch.