Most common presenting foot complaint reason for the original development of the podiatric profession.
Due to thickening/aggregation of the keratinised layers of the skin from increased mechanical forces.
‘Corns’ – lay terminology; ‘Tyloma’ – more commonly used in USA; ‘Clavus’ – old terminology.
Histologically – hyperkeratosis, increased fibroblast activity, rete pegs elongate, stratum spinosum thickens
Presence of hyperkeratotic lesions is indicative of some underlying mechanical dysfunction. It is assumed that the excessive stress for a prolonged period of time stimulates release of growth factors and inflammatory mediators