Syringomyelia, limb hypertrophy and sympathetic overactivity: a rare association

A 32-year-old man presented with uniform enlargement of right upper limb for 6 years. Examination revealed painful disorganised elbow joint along with sensory impairment in the affected limb with weakness of small muscles. The patient was given empirical antileprotic therapy from outside without any benefit. Ultrasonography showed pan-hypertrophic nature of local tissues. Although axonal type of sensorimotor neuropathy involving right ulnar and median nerve was detected in nerve conduction velocity study, biopsy of the same failed to confirm any axonal degeneration or evidence of leprosy. Considering the nature of sensory abnormality MRI of cervical spine was done which revealed a syrinx extending from C3 till D2. Tests for vasomotor tone showed positive results on the affected limb. Syringomyelia can rarely give rise to pan-hypertrophy of limb due to sympathetic overactivity, which is infrequently reported in literatures and deficient in logical grounds.