Complex sentence: Back problems with the L4, L5 and S1 regions are suspect and might suggest a "Double Crush" issue: one "crush" (nerve pinch or entrapment) in the lower back, and the second in the tunnel area.
Split into simpler sentences: Back problems with the L4, L5 and S1 regions are suspect and might suggest a "Double Crush" issue. One "crush" (nerve pinch or entrapment) in the lower back and the second in the tunnel area.