Single-fiber Electromyography in Patients with Diabetic Neuropathy

Diabetic peripheral neuropathy (DPN) is the most common microvascular complication of diabetes mellitus. Clinically, it affects the most distal extremities, first resulting in a stock and glove pattern of sensory loss. It affects both small fibers (myelinated and unmyelinated) and large myelinated nerve fibers. However, the earliest manifestations might be due to small fiber dysfunction. The diagnosis of DPN relies largely on typical history and physical examination and supported by the conventional nerve conduction study (NCS) and electromyography (EMG). However, a large number of cases might be missed from diagnosis due to small fiber involvement that manifests before large fibers. This necessitates the use of other diagnostic strategies such as single-fiber EMG, which is helpful in deciphering small fiber dysfunction and DPN earlier than NCS.