Submitted by Lisa M. Williams, MD, News Science Editorial Board
Park D. Ultrasonography of the transverse movement and deformation of the median nerve and its relationships with electrophysiological severity in the early stages of carpal tunnel syndrome
. PM R
. 2017 Nov;9(11):1085-1094. doi:10.1016/j.pmrj.2017.03.015. Epub 2017 Apr 19. PubMed PMID: 28433831.
To date, conflicting theories behind the initial pathogenic mechanism of carpal tunnel syndrome (CTS) exist. Currently, the leading views are inflammatory, resulting from compression of the median nerve and non-inflammatory, fibrosis of the subsynovial connective tissue (SSCT). More recently, researchers have investigated the transverse plane movement of the median nerve as a potential mechanism for CTS. The transverse movement of the median nerve is thought to be reduced with wrist and finger movement in CTS. Using ultrasonography, the researchers of this study designed a cross-sectional, case-controlled study measuring deformation and displacement of the median nerve as it related to severity of CTS confirmed by electrophysiological studies.
Stage 3, moderate to severe CTS confirmed by neurophysiologic studies showed a significantly lower normalized maximal change value of the median nerve movement in response to finger and wrist motions compared with CTS patients in stages 0, 1, and 2 (P <.001).
The maximum change of median nerve movement may be associated with a degree of fibrosis of connective tissue (ie SSCT) and may be a useful diagnostic ultrasound finding for determination of early onset CTS.