This condition results from denervation of areas exposed to day-to-day friction of bony prominences. The denervation may be result of any of the following diseases: * Spinal injuries * Leprosy * Peripheral nerve injury * Diabetic neuropathy * Tabes dorsalis * Transverse myelitis * Meningomyelocele * Syringomyelia
Malum perforans
Lichen spinulosus
Lichen aureus
Lichen ruber moniliformis
Herpes gladiatorum
Ichthyosis hystrix
Tinea incognita
Lawsonia inermis