source?
Dermatomes are always tricky except for very classical landmarks. Sensory skin innervations are much more variable in the human population than muscle innervation. The L4 dermatome will indeed have more lateral than medial innervation of the thigh (and more medial innervation of the leg), but I would not get stuck on this fact. Some people can have medial innervation, although no study would robustly show this because it’s not particularly clinically useful and I would expect only really really old studies to come up. Reflexes and motor weaknesses are the key things to pay attention here. I would err on accepting the change because classical dermatome maps show L4 at the lateral areas (it would be interesting to see where the original source comes from, and if they meant medial leg). FA2022 page 461 just says “anterior thigh” (nothing about lateral or medial), and page 463 just mentions the clinical findings of muscle weakness and reflexes (probably because they also know sensory findings are just not too clinically useful). Could also just consider deleting close #4 for one less card in the deck!