A Durlacher corn is a small, often intensely painful lesion that develops beside the toenail, usually along the outer edge of the fifth, or little, toe. Also called a Lister’s corn, it occupies the narrow space between the nail and the surrounding skin. Its position distinguishes it from the more familiar corn over a toe joint or beneath the forefoot. Although easily overlooked, it can make ordinary footwear uncomfortable and walking unpleasant. Understanding this condition requires attention to local pressure, toe structure, and the possibility that an apparent corn is actually an accessory portion of toenail.
Development and causes
Conventionally, a Durlacher corn is described as a localised area of hyperkeratosis: thickening of the outer skin layer in response to repeated mechanical stress. Pressure and friction stimulate keratin accumulation, producing a compact lesion that presses into sensitive underlying tissues. The narrow nail groove leaves little room for this extra material, so even a tiny lesion may cause considerable pain. A corn does not have a true root, although its dense central keratin can resemble one. Removing that material can relieve discomfort, but does not necessarily eliminate the forces responsible for its formation.
Footwear is an important contributor. Narrow toe boxes squeeze the little toe against the shoe, while firm seams or stiff uppers can concentrate pressure beside the nail. Toe deformity may increase this loading. A fifth toe that rotates inward can expose its outer nail margin to pressure from both footwear and the ground. Prominent underlying bone, reduced soft tissue cushioning, and stiffness may also contribute. Fusion of the middle and distal toe bones, termed symphalangism, has been associated with these lesions in clinical reports, although its precise importance has not been established through strong comparative research.
Symptoms and diagnosis
Patients commonly describe a sharp, focal pain at the edge of the little toenail, particularly when wearing enclosed shoes. The lesion may look like a hard sliver, an additional nail fragment, or a small yellowish thickening. Some people therefore assume that they have an ingrown toenail or fungal infection. Diagnosis usually involves careful inspection and palpation, assessment of footwear, and examination of toe alignment. A podiatrist also considers alternative explanations, including an ingrown nail, wart, foreign body, or another nail disorder. Persistent ulceration, bleeding, unusual pigmentation, or unexplained enlargement warrants further investigation rather than repeated routine corn treatment.
Assessment should also include circulation and sensation, because these influence treatment safety. The clinician should ask when symptoms occur, whether both feet are affected, and whether previous removal produced lasting relief or only a relatively brief improvement.
An important diagnostic qualification is that not everything labelled a Durlacher corn is necessarily thickened skin. Published descriptions of accessory fifth toenails show that a small additional nail plate can lie beside the main nail and resemble a corn. Histological examination in reported cases has confirmed genuine nail tissue. These accessory nails may have an associated groove or split and can occur on both feet. Consequently, clinicians should distinguish pressure-induced hyperkeratosis from a developmental nail variation, while recognising that both may coexist. This distinction matters because recurrent nail tissue will not be permanently resolved by treating it as ordinary callus.
Treatment and prevention
Initial management generally aims to reduce pressure and relieve symptoms. Shoes should provide sufficient width and depth around the toes, with soft uppers and minimal irritating seams. Carefully selected padding or a silicone toe protector may help, provided it does not make the shoe tighter. Professional reduction of a true corn can provide substantial relief by removing compacted keratin. However, recurrence is common if footwear pressure or toe deformity remains unchanged. Regular review may therefore be appropriate. Moisturising dry surrounding skin can improve comfort, but cannot correct a bony prominence or remove an accessory nail-producing structure.
Self-treatment requires caution. Digging beside the nail with blades, scissors, or sharp instruments can damage skin and introduce infection. Acid-containing corn removers may burn adjacent healthy tissue, especially in the confined nail groove. People with diabetes, neuropathy, poor circulation, or a previous foot ulcer should seek professional assessment rather than attempting removal themselves. Redness, warmth, swelling, drainage, or an open wound requires prompt clinical attention. Persistent pain despite appropriate footwear and conservative care may justify imaging or specialist assessment, particularly when an underlying bony prominence, substantial toe deformity, or accessory nail is suspected.
Surgery is reserved for selected, persistently symptomatic cases and should address the actual diagnosis. Options may include correcting a focal bony prominence or toe deformity, or removing a painful accessory nail with appropriate treatment of its matrix. Potential complications include infection, delayed healing, nail distortion, and recurrence. Evidence specific to Durlacher corns consists largely of clinical descriptions and small reports, so outcomes should not be overstated. Ultimately, successful management depends on identifying whether the problem is corn, nail, or both, reducing mechanical irritation, and choosing treatment proportionate to symptoms and risk.
References
- Haneke, E. (2015). Double nail of the little toe. Skin Appendage Disorders, 1(4), 163–167.
- Fishco, W. D. (2011). Key considerations in treating Lister’s corn. Podiatry Today.
- Alder, D. C., Fishco, W. D., & Ruch, J. A. (1998). Surgical treatment of Lister’s corn: A case illustration. Journal of the American Podiatric Medical Association, 88(1), 30–33.