Distorting UV map while normal mapping

I have a low poly hand with the three littler fingers meshed as one block. The hand is UV mapped with the three fingers painted onto the mesh block. I want to create a high poly mesh of a duplicate to bake a normal map, while using the painted UV texture as a guide for creating the high poly mesh. The problem is that when I divide the low poly mesh (CTRL R) I cannot slide the new edges to the junction of the fingers without the UV map distorting. Is there a way disconnect the edges from the map until you get the edges where you want them to be?

Have you tried pinning the UV vertices? Also, are you using multires?