Definition. – A degenerative disease of one or more of the toes, especially the smallest, characterized by linear strangulation and eventually by spontaneous amputation.
Symptoms. – This rare disease begins as a semicircular or annular constriction at the digitoplantar fold of the little toe, although the other toes may be affected. Its progress is very slow, extending over a period of five to ten years. In time a furrow encircling the toe causes strangulation with detachment but without ulceration, inflammation or pain. During this slow degeneration all elements of the toe increase two or more times in size, presenting a globular or oval mass.
Etiology and Pathology. – Ainhum is never congenital and although most cases occur in adults, it has been observed in children. Male negroes are the commonest sufferers. The disease is found chiefly in Africa, India and the West Indies but it occasionally seen in our country. It is no doubt a trophoneurosis, although parasitic and traumatic origins have been suggested.
Prognosis and Treatment. – Spontaneous amputation of the affected member or members may be expected. The general health is not necessarily affected. Treatment consists in early transverse incision of the constricting band and if this does not succeed in checking the disease, nothing remains save amputation.
Fig. – 118 – Ainhum of the little toe. Surgical amputation (courtesy of Drs. Kaufman and Schmahl.).