Clinical characteristics and electrodiagnostic features in patients with carpal tunnel syndrome, double crush syndrome, and cervical radiculopathy

Similar unilateral neck and upper limb symptoms are often due to various entrapment neuropathies; carpal tunnel syndrome (CTS) and cervical radiculopathy (CR) are common causes among them. Therefore, we investigated the clinical characteristics and electrodiagnostic features of patients with carpal tunnel syndrome, cervical radiculopathy, and both conditions, called double crush syndrome (DCS). The medical records and electrodiagnostic reports of 866 patients with suspected CTS and CR visited a tertiary-care hospital were retrospectively analyzed. After excluding 101 patients with confounding conditions, 151 (20%) patients were diagnosed to have sole cases of CTS; 362 (47%) patients were diagnosed to have sole cases of CR; 198 (26%) patients were diagnosed to have DCS, while 54 (7%) patients had mere symptoms. Sole cases of CR had the highest incidences of neck pain, upper back pain, wrist and hand weakness. Female patients had the highest incidences of all the diseases in their sixth decade. Male patients had comparably distinguished high occurrence of all the diseases in their fifth to sixth decades. Although comparison of nerve conduction studies between patients with mere symptoms and patients with sole cases of CTS or DCS showed statistical differences, comparison between the latter two revealed no difference. We found most patients referred for electrodiagnostic studies had cervical radiculopathy. High concomitant occurrence of CTS and CR suggests cautious evaluation of patients with upper limb symptoms is important, because the management of these conditions is quite different.