Carpal tunnel syndrome: Assessment of correlation between clinical, neurophysiological and ultrasound characteristics

Objectives: To evaluate the relationship between symptoms, clinical severity, neurophysiological characteristics with median nerve cross-sectional area (CSA) at the level of carpal tunnel inlet at ultrasonography (USG) and its utility in diagnosis of carpal tunnel syndrome (CTS). Materials and Methods: Prospective study of 30 patients with symptoms of CTS, attending to the Neurology out patient department (OPD) at University Teaching Hospital. A multidimensional assessment of CTS was done using historic and objective scale (Hi-Ob scale) for clinical severity, Boston carpal tunnel questionnaire (BCTQ) for patient-oriented measures, neuro physiologic studies of median nerve at wrist and USG to measure median nerve CSA at carpal tunnel inlet. Results: Thirty patients included in the study (22 women and 8 men). Mean of CSA was 12.69 mm 2 (SD2.67). Association between BCTQ score value and inlet values was assessed by Karl Pearson correlation coefficient ( r = 0.376, P = 0.04). There was positive association with BCTQ scores and CSA of median nerve at carpal tunnel inlet. To compare clinical severity scale (Hi-Ob) and USG CSA, analysis of variance was performed (F value) and Scheffe′s multiple comparison test was used to find group difference (grades 1 and 2 P < 0.001, grades1 and 2P P < 0.001, grade 2 differs with grade 2P P < 0.006). As the number of patients is less in minimal, mild and severe groups, the difference between neurophysiological groups and mean of CSA was not statistically significant. Conclusion: A positive correlation exists between USG findings and all the conventional measures of CTS severity