Ultrasound Role in Diagnosis of Carpal Tunnel Syndrome and Postoperative Evaluation in Endoscopic Carpal Tunnel Release

Abstract

Carpal tunnel syndrome (CTS) represents about 90% of all entrapment neuropathies and is caused by entrapment of the median nerve while passing in the carpal tunnel. US has revealed equal effectiveness as magnetic resonance imaging (MRI) in diagnosis of CTS; however further attention should be given in case of equivocal results from nerve conduction studies (NCS) and/or before endoscopic surgical intervention. This study was conducted to evaluate the role of US in diagnosis and treatment of CTS which was done by endoscopic release. This is a prospective study including patients having CTS who were treated by endoscopic release between December 2017 and December 2018. All cases were evaluated by electrophysiological studies and US at the preoperative period. US was used to measure the cross sectional area (CSA) of the median nerve. Patients underwent endoscopic carpal tunnel release and were called for follow up after 1, 3, and 6 months for clinical and US assessment of the median nerve. Forty cases were included with mean age of 27.85 years. Numbness was the predominant symptom (92.5%) followed by wrist pain (85%). The mean diameter of median nerve showed a significant decrease at different time points (P < 0.001). The sensitivity of US in diagnosis of CTS was 87.5% in the preoperative assessment as compared to electrophysiological study. The sensitivity of US in detecting the improvement of CTS as compared to clinical examination increased from 28% at 1 month postoperative, 53.4% at 3 months to 92.1% at 6 months. Ultrasonography is a sensitive non-invasive diagnostic tool in diagnosis of CTS preoperative and diagnosis of improvement of the patients postoperatively especially at 6 months.