Relationship between interpretation and accuracy of the upper limb neurodynamic test 1 in carpal tunnel syndrome.
OBJECTIVE
This prospective diagnostic test study evaluated the relationship between interpretation criteria and accuracy of the Upper Limb Neurodynamic Test 1 (ULNT1) in the diagnosis of carpal tunnel syndrome.


METHODS
A blind comparison with a reference criterion of typical clinical presentation and abnormal median nerve conduction was used. All subjects were first tested with nerve conduction studies and then with ULNT1. Each examiner was blinded to the results collected by the other examiners.


RESULTS
We analyzed 47 subjects and 84 limbs. Considering ULNT1 as positive in the presence of reproduction of symptoms only in the thumb or lateral 2 fingers, we estimated sensitivity to be equal to 40% (95% confidence interval [CI], 0.256-0.564), specificity 79.59% (95% CI, 0.664-0.885), positive predictive value 58.33% (95% CI, 0.388-0.755), negative predictive value 65% (95% CI, 0.524-0.758), positive likelihood ratio 1.96 (95% CI, 1.275-3.012), and negative likelihood ratio 0.7538 (95% CI, 0.490-1.159). Considering the increase of symptoms with contralateral or decrease of symptoms with ipsilateral cervical side bending as mandatory positivity criterion, specificity improved, but sensitivity decreased.


CONCLUSIONS
Our investigation suggests that the reproduction of symptoms in the thumb or lateral 2 fingers of the affected arm during ULNT1 has weak diagnostic accuracy for carpal tunnel syndrome.
Lecturer Manual Therapy, Department of Internal Medicine, Geriatrics and Nephrology, Section of Occupational Medicine, Alma Mater Studiorum University of Bologna, Bologna, Italy.
Carla
C
Vanti
Roberta
R
Bonfiglioli
Monica
M
Calabrese
Francesco
F
Marinelli
Francesco Saverio
FS
Violante
Paolo
P
Pillastrini
D000328:Adult; D002349:Carpal Tunnel Syndrome / Q000175:diagnosis*; D002684:Chiropractic / Q000379:methods; D016001:Confidence Intervals; D004568:Electrodiagnosis / Q000379:methods; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008475:Median Nerve / Q000503:physiopathology*; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D009460:Neurologic Examination / Q000379:methods; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016037:Single-Blind Method; D034941:Upper Extremity / Q000294:innervation / Q000503:physiopathology