Abstract
Purpose: The aim of this study was to redefine the localization of the thenar motor branch (TMB) of the median nerve in relation to the surface landmarks which are in routine use.
Methods: The study was performed in 37 hands of 34 patients who underwent carpal tunnel release. All of the patients were women and the mean age was 50 (35–67). A radiological marking technique was used to determine the localization of the TMB, the middle finger radial side line and the Kaplan’s cardinal line. For marking TMB a circumscribing soft radioopaque yarn was used while the surface landmark lines were demonstrated by taping one K-wire for each. An image intensifier print image was obtained for each case and the distances between the markers of the TMB and the wires were measured.
Results: The TMB had a mean ulnar offset of 12.6 mm (4.0–19.7) from the middle finger radial side line and located 4.4 (0–9.5) mm proximal to the cardinal line.
Conclusion: During the carpal tunnel release operations one must pay more attention to the localization of the TMB of the median nerve because it was found to be 12.6 mm ulnar than that was described in classic literature.
Theses abstracts were prepared by Professor Roger Lemaire. Correspondence should be addressed to EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
