Small muscle wasting of the hands in diabetes mellitus.

The clinical features and peripheral somatic and autonomic nerve function were studied in 10 diabetic subjects (nine men, one woman; mean age 59 yr, range 41-68 yr; mean duration of diabetes 20 yr, range 8 mo to 33 yr) with generalized small muscle wasting of the hands. Five patients were insulin-dependent and five non-insulin-dependent. Nine had retinopathy (two proliferative, seven background), five nephropathy, two ischemic heart disease, and seven peripheral vascular disease. Nine patients had clinical evidence of sensory peripheral neuropathy and absent reflexes in the lower limbs. Eight patients had distal sensory impairment and/or absent reflexes in the upper limbs. Seven had two or more symptoms of autonomic neuropathy. Nerve conduction measurements in the median, ulnar, and lateral popliteal nerves showed that all patients had moderate to severe polyneuropathy affecting both motor and sensory fibers. Nine had one or more abnormal cardiovascular autonomic function tests. Electromyography of affected muscles in the hands showed changes of chronic partial denervation and collateral reinnervation in all cases.