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What is Trophic ulcers are caused by -a) Leprosyb) Buerger's diseasec) Syringomyeliad) DVTe) Varicose veins and explain in detail?
Trophic ulcers develop as the result of repeated trauma to the insensitive part of the body. So some neurological disturbance is usually the cause behind this ulcer formation.
These neurological disorders are : 

- spinal or peripheral nerve injury               
- diabetic neuropathy
- leprosy  
- tabes dorsalis     
- syringomyelia  
- transverse myelitis, etc.

Trophic ulcers are commonly seen on the heel and ball of the foot when the patient is ambulatory and on the buttocks and back of heel if the pt. is bed ridden (k/a bed sores)