Carpal tunnel syndrome in patients with and without diabetes mellitus in Upper Egypt: The impact of electrophysiological and ultrasonographical studies
Background: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy in the upper extremity. Nerve conduction studies (NCS) is the most valid way of diagnosing CTS in combination of these clinical symptoms together with positive signs by physical examination. Ultrasonography is a useful non-invasive diagnostic method for CTS and there is considerable correlation between the electrophysiological tests and the measurements of cross-sectional area (CSA) by ultrasonography. Many studies have shown that the carpal tunnel syndrome seems to occur more frequently in patients with diabetes mellitus and might be associated with the duration of diabetes mellitus, microvascular complications and degree of glycemic control. Although diabetes mellitus is a risk factor for CTS, reports about median nerve CSA measurements between CTS patients with and without DM are scant. This prospective study aimed to evaluate whether or not ultrasonographic findings of the median nerve is different between DM and non-DM-CTS patients. To correlate the diagnostic results in both DM and non-DMCTS patients.
Patients and methods: Thirty six non-diabetic patients and twenty five diabetic patients with CTS were assessed. All patients were subjected to thorough history taking, full clinical examination, electrophysiological assessment of wrists and gray scale ultrasonography (US).
Results: High mean cross sectional area of median nerve (CSA) on ultrasonographical studies was detected with non-significant difference between both groups. Additionally, a non-significant difference for flattening ratio was found between two groups. Moreover, there was a highly significant positive correlation between electro diagnostic and ultrasonographic results in diabetic patients.
Conclusion: The CSA of median nerve is larger in CTS hands in both DM and non-DM patients. Mean electro-diagnostic parameters were not significant predictors of CTS in patients with diabetes. The combination of electrophysiological and ultrasonography provides diagnostic effective tools across the entire spectrum of CTS in diabetic and non-diabetic patients. Nevertheless, screening for DM in patients with CTS is not recommended.
Keywords: Carpal tunnel syndrome (CTS), Diabetes mellitus (DM), Diabetic polyneuropathy (DPN), Electrophysiological and ultrasonography (US)