Clavus (medicine)

Key facts and history

The Latin term "clavus" is considered somewhat dated, while the modern medical word is Greek "heloma".^[3] Hard corns are especially problematic for people with insensitive skin due to damaged nerves, such as those with diabetes mellitus.^[2] Avoiding pressure often involves changing to more comfortable footwear or using shoe inserts.^[4] In extreme cases, surgery may be performed if other treatments are ineffective.^[4]

In the United States, the term "tyloma" is employed with greater frequency than elsewhere.^[3][1] A heloma durum (also called clavus durus) designates a hard corn, while a heloma molle (or clavus mollis) refers to a soft corn.^[3] The conical shape of corns leads to heightened pressure at the apex, which may result in deep tissue injury and ulcer formation.^[2] Immediate pain relief can be achieved by paring down the lesions.^[2]

A corn plaster, consisting of a felt ring containing salicylic acid, is a widely used treatment.^[2]

What the research sources say

The PodiaPaedia entry states that corns are due to thickening of the keratinised skin layers from increased mechanical forces.^[1] It lists subtypes including Heloma Durum, Heloma Molle, and Heloma Miliare.^[1] Imaging studies, such as a plain radiograph or CT scan, can detect underlying bony abnormalities causing pressure.^[5] A skin biopsy may be performed to rule out other possible diagnoses.^[5]