Imaging Studies
- The radiographic manifestations of ainhum are diagnostic.[12, 13]
- Initially, a radiolucent band can be observed constricting the base of the involved toe, with distal swelling.
- Osteolysis develops in the distal and middle phalanges, with a characteristic tapering effect.
- Ultimately, the bone narrows until it fractures and autoamputates.
- The radiographic appearances in pseudoainhum are similar or identical to true ainhum.
Histologic Findings
Histologically, ainhum shows fissuring and epidermal hyperkeratosis and parakeratosis, which is followed by a fibrotic reaction under the deepening fissure. The fibrosis is predominately composed of collagen. As scar tissue contracts, it constricts and narrows neurovascular bundles. Histologic appearances in pseudoainhum are similar or identical to those observed in true ainhum.
Greene JT, Fincher RM. Case report: ainhum (spontaneous dactylolysis) in a 65-year-old American black man. Am J Med Sci. Feb 1992;303(2):118-20. [Medline].
Mendelson DS, Chan KF, Song IS. Spontaneous dactylolysis with pain in a 58-year-old American Black man. JAMA. Oct 2 1981;246(14):1591-2. [Medline].
da Silva Lima JF. On ainhum. Arch Dermatol. 1880;6:367.
Olivieri I, Piccirillo A, Scarano E, Ricciuti F, Padula A, Molfese V. Dactylolysis spontanea or ainhum involving the big toe. J Rheumatol. Dec 2005;32(12):2437-9. [Medline].
Cole GJ. Ainhum: An account of fifty-four patients with special reference to etiology and treatment. J Bone Joint Surg Br. Feb 1965;47:43-51. [Medline].
Wells TL, Robinson RC. Annular constrictions of the digits. AMA Arch Derm Syphilol. Nov 1952;66(5):569-72. [Medline].
Cunliffe WJ. Ainhum and pseudo-ainhum. In: Rook A, Wilkinson DS, Ebling FJ. Textbook of Dermatology. Vol 2. Oxford: Blackwell Scientific; 1979:1638.
Demis DJ. Ainhum, pseudoainhum, and tourniquet syndrome. In: Demis DJ, Dobson RL, McGuire J. Clinical Dermatology. 7th ed. Hagerstown, Md: Harper & Row; 1979:4-47.
Mallory SB. An Illustrated Dictionary of Dermatologic Syndromes. New York, NY: The Parthenon Publishing Group; 1994:Appendix.
Castori M, Valiante M, Ritelli M, et al. Palmoplantar keratoderma, pseudo-ainhum, and universal atrichia: A new patient and review of the palmoplantar keratoderma-congenital alopecia syndrome. Am J Med Genet A. Aug 2010;152A(8):2043-7. [Medline].
Bassetto F, Tiengo C, Sferrazza R, Belloni-Fortina A, Alaibac M. Vohwinkel syndrome: treatment of pseudo-ainhum. Int J Dermatol. Jan 2010;49(1):79-82. [Medline].
Fetterman LE, Hardy R, Lehrer H. The clinico-roentgenologic features of ainhum. Am J Roentgenol Radium Ther Nucl Med. Jul 1967;100(3):512-22. [Medline].
Jemmott T, Foster AV, Edmonds ME. An unusual cause of ulceration: ainhum (dactylolysis spontanea). Int Wound J. Sep 2007;4(3):251-4. [Medline].
Rossiter JW, Anderson PC. Ainhum: treatment with intralesional steroids. Int J Dermatol. Jun 1976;15(5):379-82. [Medline].
Allyn B, Leider M. Dactylolysis spontanea (ainhum). Report of a case treated by the surgical procedure known as Z-plasty. JAMA. May 25 1963;184:655-7. [Medline].
Browne SG. Ainhum. Int J Dermatol. Jun 1976;15(5):348-50. [Medline].
Dent DM, Fataar S, Rose AG. Ainhum and angiodysplasia. Lancet. Aug 22 1981;2(8243):396-7. [Medline].
Hunt M, Glucksman EE. Ainhum presenting to the accident and emergency department. Arch Emerg Med. Dec 1993;10(4):324-7. [Medline].
Kean BH, Tucker HA, Miller WC. Ainhum: a clinical summary of forty-five cases on the Isthmus of Panama. Trans R Soc Trop Med Hyg. 1946;39:331-4.
Ramesh V, Misra RS, Mahaur BS. Pseudoainhum in porokeratosis of Mibelli. Cutis. Feb 1992;49(2):129-30. [Medline].
Schulz EJ. Genodermatoses. Dermatol Clin. Oct 1994;12(4):787-96. [Medline].
Sharma RC, Sharma AK, Sharma NL. Pseudo-ainhum in discoid lupus erythematosus. J Dermatol. Apr 1998;25(4):275-6. [Medline].

