BACKGROUND: Mechanically induced hyperkeratotic lesions (corns and calluses) are among the most common foot problems in older people. However, their aetiology is not well understood. AIM: To compare the magnitude of pressures generated under the foot when walking in older people with and without plantar calluses. METHODS: Peak plantar pressure measurements were obtained from 292 participants (99 men and 193 women) aged 62-96 years (mean +/- SD 77.6 +/- 6.9) recruited from a retirement village and a university health sciences clinic. Comparisons were then made between callused and noncallused regions of the foot. RESULTS: In total, 151 participants (52%) had at least one plantar callus. Those with plantar calluses were more likely to be female, have moderate to severe hallux valgus, and at least one lesser toe deformity. Regional peak plantar pressures were significantly higher in people with calluses under the second metatarsophalangeal joint (2.34 +/- 0.46 vs. 2.12 +/- 0.51 kg/cm(2), P = 0.001), the third to fifth metatarsophalangeal joints (1.71 +/- 0.46 vs. 1.50 +/- 0.51 kg/cm(2), P = 0.009) and the hallux (1.40 +/- 0.34 vs. 1.23 +/- 0.47 kg/cm(2), P = 0.007) compared with people without calluses under these sites. CONCLUSION: Plantar pressures are significantly higher under callused regions of the foot in older people. Raised pressure may play a role in the development of plantar calluses by accelerating the turnover rate of keratinocytes in the epidermis. Future studies should focus on evaluating the efficacy of pressure-relieving interventions in the prevention and treatment of keratotic disorders in older people.