—We are grateful for Dr Katirji's comments, but do not agree with his conclusion that the lateral cutaneous nerve of the forearm (LCN) has as its primary source fibers from the C-5 root. Our review of the anatomic literature as well as our clinical experience differ from his. Keegan and Garrett1 combined the experience of previous investigators with their own observations and concluded that C-5 primarily supplies the skin of the lateral aspect of the upper arm, while only occasionally extending into the forearm. On the other hand, C-6 supplies the same area as the LCN distribution, as well as the lateral portion of the hand. Kimura2 states that sensory nerve action potential studies of the LCN are a good test for C-6. This latter coincides with our experience.It is important to point out that most peripheral nerves, including the LCN, have input from multiple roots. Thus
Hackett ER, Kline DG, Happel LT. Brachial Plexus Lesions-Reply. Arch Neurol. 1986;43(12):1222. doi:10.1001/archneur.1986.00520120008004
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