Magnificent MRI and fascinating selective nerve fascicle damage

A century ago less 2 years, the distinguished French neurologist Joseph Dejerine and his colleagues(1) meticulously studied the clinical sequelae of nerve lesions in World War I soldiers. They showed clearly that partial lesions in a major peripheral nerve can produce very selective sensory and motor deficits that could mimic the clinical picture of damage to just a distal branch of that nerve. Thus a proximal nerve lesion can masquerade as a more distal one, befuddling the clinician and causing important errors in localization. Unfortunately, these important observations have been lost in the mists of time.