- 1 Other Names
- 2 Background
- 3 Pathophysiology
- 4 Risk Factors
- 5 Differential Diagnosis
- 6 Clinical Features
- 7 Evaluation
- 8 Classification
- 9 Management
- 10 Rehab and Return to Play
- 11 Complications and Prognosis
- 12 See Also
- 13 References
- Subungal Exostosis
- Dupuytren’s exostosis
- This page refers to Subungal Exostosis (SE), a relatively uncommon benign bone tumor that occurs in the distal phalanges of the toes
- First described by Dupuytren in 1817
- There is a paucity of literature to describe the epidemiology
- 70-80% occur on the hallux
- Osteocartilaginous tumor of the distal phalanges of the foot
- Patients typically present with pain, erythema, and deformity of the nail bed
- Misdiagnosis and delayed diagnosis of this lesion are common
- Rarely, this can occur in the phalanges of the upper extremity
- Most commonly reported on the thumb
- Poorly understood
- Proposed etiologies
- Most commonly accepted theory is reactive metaplasia resulting from microtrauma
- However there is no definitive evidence to support a single pathogenesis
- Hereditary abnormality
- Linked to translocation t(X;6)(q22;q13-14)
- This implies it is a true neoplastic process rather than reactive response to trauma
- Activation of a cartilaginous cyst
- Subungal Exostosis
- Histology: cartilaginous cap of exostoses is made of fibrocartilage
- Bone is formed directly from fibrous tissue
- Subungual Osteochondroma
- Some controversial whether this is the same disease
- Histology: hyaline cartilage and is confluent with the underlying trabecular and cortical bone
- Bone is derived from enchondral ossification
- Multiple Hereditary Exostoses
- Fractures & Osseous Disease
- Traumatic/ Acute
- Stress Fractures
- Other Osseous
- Dislocations & Subluxations
- Muscle and Tendon Injuries
- Ligament Injuries
- Pain, erythema, and deformity of the nail bed
- Patients endorse significant impact on quality of life
- Physical Exam: Physical Exam Foot
- Affected toe reveals a firm, fixed nodule with a hyperkeratotic smooth surface at the distal end of the nail plate
- Location is typically dorsomedial mass
- May see elevation and periungual ulceration and infection
- Nail plate is often deformed
- Special Tests
- Standard Radiographs Foot
- Pedunculated radiopaque mass on the dorsomedial surface of the distal phalanx.
- Noncontinuity and continuity with the cortex are both described in the literature
- May be described as a trabeculated pattern of cancellous bone with or without a defined cortex
- Some physicians/ podiatrist consider it to be imaging modality of choice
- Reason is due to the fibrocartilaginous component that is not radiographically apparent
- Not applicable
- Disease process is progressive, management is primarily surgical
- Majority of cases
- Marginal surgical excision
Rehab and Return to Play
- No clear guidelines
Return to Play/ Work
- No clear guidelines
Complications and Prognosis
- Recurrence of lesion
- Up to 4% (need citation)
- Postsurgical deformity
- Up to 16% (need citation)
- Ingrown Toenail
- Dupuytren GF. On the Injuries and Diseases of Bones, translated and edited by F Le Gros Clark, pp 408-411, Sydenham Society, London, 1847.
- Carroll RE, Chance JT, Inan Y. Subungual exostosis in the hand. J Hand Surg Br. 1992;17:569–574.
- Miller-Breslow A, Dorfman H: Dupuytren's (subungual) exostosis. Am J Surg Pathol 12: 368, 1988.
- Vázques-Flores H, Domínguez-Cherit J, Vega-Memije ME, et al: Subungual osteochondroma: clinical and radiologic features and treatment. Dermatol Surg 30: 1031, 2004.
- Pérez-Palma L, Manzanares-Céspedes MC, Veciana EG. Subungual exostosis. J Am Podiatr Med Assoc 2018;108:320–33. doi: 10.7547/17-102
- Gavillero A, Arxé D, de Planell E, et al: Estudio estadístico en cirugía ungueal. El Peu 25: 20, 2005.
- Image courtesy of MDedge.com, "Subungual Exostosis"
- Suga H, Mukouda M. Subungual exostosis. Ann Plast Surg. 2005;55:272–275.
- Dal Cin P, Pauwels P, Poldermans LJ, Sciot R, Van den Berghe H. Clonal chromosome abnormalities in a so-called Dupuytren’s subungual exostosis. Genes Chromosomes Cancer. 1999;24: 162–164.
- Ippolito E, Falez F, Tudisco C, Balus L, Fazio M, Morrone A. Subungual exostosis. Histological and clinical considerations on 30 cases. Ital J Orthop Traumatol. 1987;13:81–87.
- Stark JD, Adler NN, Robinson WH. Hereditary multiple exostoses. Radiology. 1952;59:212–215.
- Case courtesy of Dr Ayush Goel, Radiopaedia.org, rID: 74749
- Higuchi K, Oiso N, Yoshida M, et al. Preoperative assessment using magnetic resonance imaging for subungual exostosis beneath the proximal region of the nail plate. Case Rep Dermatol 3: 155, 2011