Lead neuropathy with wrist drop but preservation of the supinator longus muscle

"The most characteristic (form of lead neuropathy) is the paralysis of the extensors of the hands, producing the well-known wrist-drop. The muscles supplied by the musculo-spiral (radial) nerve are the ones to suffer, although curious exceptions for some unknown reason are seen in the cases of the supinator longus and the extensor of the metacarpal bone of the thumb, both of which invariably escape. The type of paralysis is that of a neuritis. The muscles waste and give the reactions of degeneration.” (Source: Lloyd JH. The diseases of occupations. In: Stedman TL, editor. Twentieth Century Practice: An International Encyclopedia of Modern Medical Practice by Leading Authorities of Europe and America. Volume 3: Occupation Disease, Drug Habits, and Poisons. New York: William Wood and Company, 1895:311-496. Public domain.)