Dermatomal charts vary

Dermatomal charts vary and previous studies have demonstrated significant individual subject variation (see publication on the 11th of April). This article analysed distribution of L5 and S1 dermatomes. 

Subjects included had a proven nerve root compression (NRC); radiologically and surgically. In the study subjects were asked to complete a diagram of their pain and pins and needles distribution. The results showed a significant overlap of dermatomes, as most patients indicated pain or pins and needles in more than one dermatomal area. For example from the patients with L5 NRC, 22% showed pain in the front of the leg, 61% pain on the back of the leg and 13% in both, front and back. 

The main conclusions from this article are: 
- Individual subject variation is significant. 
- Self-reported distribution of pain and pins and needles from a single NRC extends over many dermatomes. 
- The most frequently indicated dermatome does not often correspond to the actual anatomical root affected. 
- Patient self-report is an unreliable method of identification of the level of NRC. 
> From: Taylor et al., Spine 12 (2013) 995-998. All rights reserved to Lippincott Williams & Wilkins.