In patients who have died of advanced motor neuron disease, one of the most impressive gross anatomical findings is the disparity in size and texture of the anterior and posterior spinal nerve roots, brought about by progressive atrophy of the former and generally good preservation of the latter.
When it comes to demonstrating this difference in photographs for medical students, resident teaching, or for neuropathology conferences, it is rather difficult to arrange the respective nerve root pairs in a fashion that would make them easy to compare,1 because whether the spinal cord is photographed from the front or the back, the dorsal and ventral nerve roots tend to overlap.2,3 Moreover, in the cauda equina, photographed in the usual way, the motor and sensory
Fig 1.—Side view of spinal cord and cauda equina from 54-year-old woman with advanced motor neuron disease. Atrophic anterior roots (right) combed apart from posterior