| ObjectiveTo study the sonographic appearance of ulnar nerve in the control group and patients with cubital tunnel syndrome(CTS). To evaluate the value of high-resolution ultrasonography in the clinical application of CTS.Materials and MethodsThe patients group:41arms from34CTS patients in Shan-xi Medical University No.2Hospital orthopedics department from2011.3to2011.12. The control group:60arms from30healthy volunteers without cubital tunnel syndrome and history of peripheral Neuritis.41arms from34CTS patients underwent a real-time ultrasound scanner to observe the ulnar nerve and measure its cross-sectional area(CSA) and long-axis diameter. The control group were scanned to get the normal images of the ulnar nerve and measure its CSA and long-axis diameter. And calculated CSA swelling ratio respectively. The indexes were compared between two groups. Made receiver operator characteristic curves (ROC curves)to get the diagnostic criteria of the indexes for CTS. And evaluated the diagnostic value of the indexes. The Pearson correlation analysis between maximal CSA and motor nerve conduction velocity (MNCV) in the patients group was then performed.Results1.The appearance of normal ulnar nerve:ulnar nerve was round or oval hypoechoic area transversely. It was wrapped by hyperechoic line and was honeycomb internally; ulnar nerve was hypoechoic bunch whose inward had parallel hyperechoic lines when scanned in a longitudinal plane.2.The appearance of CTS in the patients group:the ulnar nerve of most CTS became narrow or flat at compression site while it turned to enlarged and the fascicular texture turned to vague at the proximal part of the compression; The compression site could not be found in some CTS and the nerve was swollen in elbow. The different pathogeny could be detected:osteophyte, ganglion cyst, allotopia anconeus, suspicious tendon injury, articular effusion and so on.3.The difference of CSA, long-axis diameter and CSA swelling ratio between two groups were significant in statistics by adopting Independent-Samples T’ Test(unequal variances). From ROC curves of the indexes, the diagnostic criterion of CSA was>0.075cm2for CTS. Sensitivity was90.2%and specificity was95.0%at this criterion; the diagnostic criterion of long-axis diameter was>0.2295cm for CTS. Sensitivity was80.5%and specificity was75.0%at this criterion; the diagnostic criterion of CSA swelling ratio was>1.74for CTS. Sensitivity was92.7%and specificity was96.7%at this criterion. The diagnostic value of CSA swelling ratio and CSA were higher than long-axis diameter, and the value of CSA swelling ratio was highest. CSA combined with CSA swelling ratio could improve the sensitivity.4.The correlation between maximal CSA and MNCV in the patients group was negative correlation and the Pearson correlation coefficient was-0.546.Conclusions1.High-resolution Ultrasound can display neural form of CTS and discover the cause of most CTS, providing morphologic information for the therapy.2.High-resolution Ultrasound can measure CSA of the ulnar nerve and calculate CSA swelling ratio, providing method for the diagnosis of CTS.3.High-resolution Ultrasound is a new, noninvasive, economic and effective examination method for CTS. |
