Weekly Case

Title : Case 632

Age / Sex : 65 / F

Chief complaint : Rt wrist and hand tingling sense for several years

What is your diagnosis?

Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).

Courtesy : Min-Yung Chang, 
National Health Insurance Service Ilsan hospital



Answer:  carpal tunnel syndrome with bifid median nerve


Findings: Two nerve bundles of median nerve in the distal forearm and in the carpal tunnel, to suggest bifid median nerve.

          Abrupt caliber change at distal carpal row, to suggest carpal tunnel syndrome.


Differential Diagnosis: None



Discussion: Prevalence of a bifid median nerve is variably reported from 2.8% to 18%. A bifid median nerve may be accompanied by an accessory artery, the persistent median artery of the forearm, which lies in between the two nerve bundles (not definite in this patient).

Association between the bifid median nerve and carpal tunnel syndrome is controversial.

In initial anatomic description by Lanz in 1977, a bifid median nerve was thought to be predisposed to compression in the carpal tunnel because of its relatively higher cross-sectional area compared with a nonbifid median nerve. A recent study of 1026 wrist US with/without carpal tunnel syndrome, however, an association with definite carpal tunnel syndrome was not found





  1. Lanz U. Anatomical variations of the median nerve in the carpal tunnel. J Hand Surg Am 1977;2(1):44–53.

  2. Bayrak IK, Bayrak AO, Kale M, Turker H, Diren B. Bifid Median Nerve in Patients With Carpal Tunnel Syndrome. Journal of Ultrasound in Medicine. 2008;27(8):1129-36.

  3. Klauser AS, Halpern EJ, Faschingbauer R, Guerra F, Martinoli C, Gabl MF, et al. Bifid Median Nerve in Carpal Tunnel Syndrome: Assessment with US Cross-sectional Area Measurement. Radiology. 2011;259(3):808-15.

  4. Walker FO, Cartwright MS, Blocker JN, Arcury TA, Suk JI, Chen H, et al. Prevalence of bifid median nerves and persistent median arteries and their association with carpal tunnel syndrome in a sample of latino poultry processors and other manual workers. Muscle & Nerve. 2013;48(4):539-44.


Correct Answer
Total applicants 30 Correct answers 5
Name Institution
이지현 삼성서울병원, 전문의
조은경 새움병원, 전문의
김기욱 국군수도병원, 전문의
신재환 국군춘천병원, 전문의
김성진 365병원, 전문의
Semi-Correct Answer
Total applicants 30 Semi-Correct answers 24
이규정 고대안암병원, 전문의
서현주 전문의
김지은 서울대학교병원, 전문의
윤유성 순천향대 부천병원, 전문의
김주원 담양사랑병원, 전문의
송윤아 전문의
강지희 서울대학교병원, 전문의
김동언 국군양주병원, 전문의
전인환 전문의
조영민 전문의
김동수 전공의
이광진 청주프라임 병원, 전문의
이혜란 전문의
이성욱 단국대병원, 전공의
장성원 중앙보훈병원, 전공의
백승진 분당차병원, 전공의
문옥련 전공의
최형인 군의관, 전문의
김유진 전문의
여현정 전문의
박병진 국군강릉병원, 전문의
왕현혜 선정형외과, 전문의
성시윤 국군춘천병원, 전문의
안태란 삼성서울병원, 전문의

  • 관리자 ( 2019-08-12 16:19:39 )
    carpal tunnel syndrome과 bifid median nerve 둘 다 쓴 경우에만 정답으로 하였고, 둘 중 하나만 쓴 경우는 semicorrect answer로 하였습니다.