Talar callosity ('prayer foot') in a haemodialysis patient.

A 68-year-old male haemodialysis patient of Asian origin with end-stage renal failure was being evaluated for renal transplantation. His underlying renal disease was unknown. On examination, he was found to have a 13-mm hyper-keratotic nodule on the left foot, antero-medial to the lateral malleolus, with a surrounding area of hyper-pigmentation and lichenification (Figure 1, panel A). A clinical diagnosis of talar callosity (‘prayer foot’) was made [1].

Fig. 1

(A) 13-mm hyper-keratotic nodule on the left foot of the patient with a surrounding area of hyper-pigmentation and lichenification. (B) ‘Julus’ posture during prayer, with the foot touching and rubbing against the floor under body pressure.

This peculiar skin lesion is seen in devout Muslims as a result of regular prayers in the sitting posture (known as ‘julus’, Figure 1, panel B), with the foot touching and rubbing against the floor under body pressure. The left foot is usually affected owing to the asymmetric posture. A similar mechanism caused talar callosities in tailors in 19th-century England. Callosities may also occur on the forehead as a sequel to prostration in the ‘sajdah’ posture [2], with rubbing of the head against the floor or a prayer stone (‘mohr’). Talar callosities are harmless and rarely necessitate histological proof of the diagnosis. Histology would show epidermal hyperplasia and hyper-keratosis [1]. Surgical removal is sometimes performed for cosmetic reasons although recurrence has been described. Altering the position of prayer might help but the Muslim faith only permits this under exceptional circumstances, such as severe illness.

It has not escaped our attention that a whole range of dermatological signs is associated with religious practice [3], including blisters on the knees in devout Christians, allergy to ‘kumkum’ (the red powder applied to the centre of the forehead in Hindu women) and dermatitis due to ‘tefillin’ (the leather boxes and straps used in the Jewish faith). The umbrella term of ‘devotional dermatoses [3]’ has been coined for these diseases (if they are to be regarded as such). Their presence can be an important clue to religious factors that may affect patient care.

Conflict of interest statement. None declared.