Related Experiment Video
Updated: Aug 13, 2026
Nerve Ultrasound Protocol to Detect Dysimmune Neuropathies
Published on: October 7, 2021
Efficient electrodiagnosis of polyneuropathy-a targeted three-nerve conduction study protocol
Orit Mazza1,2,3, Eyal Heled4,5, Mohammad Khamaisi5
1Department of Orthopedics, Loewenstein Rehabilitation Medical Center, Raanana, Israel.
Introduction:
Electrodiagnostic testing is central to the evaluation of polyneuropathy, yet substantial variability exists in nerve selection and testing protocols. This study aimed to identify the minimum nerve set that provides high sensitivity and overall diagnostic accuracy while retaining adequate specificity. Testing two motor and two sensory nerves was hypothesized to be diagnostically sufficient.
Methods:
We conducted a retrospective cross-sectional cohort study using a deidentified database from the electrophysiology laboratory at Sheba Medical Center. Patients diagnosed with polyneuropathy were compared with individuals who had normal nerve conduction studies. Groups were matched for age and sex, and patients with coexisting conditions such as mononeuropathies or polyradiculopathies were excluded. Associations between nerve conduction parameters and polyneuropathy were examined using chi-square analyses. Parameters with significant associations were entered into separate multivariable logistic regression models for sensory and motor nerves. ROC analyses evaluated individual nerves and progressively expanded nerve-testing protocols. Optimal sensitivity and specificity were determined.
Results:
Among 455 patients, 259 had polyneuropathy, yielding 91 matched patient-control pairs. Binary sensory abnormalities of the sural and ulnar nerves were the strongest and most informative discriminators. Motor abnormalities were most prominent in the tibial and ulnar nerves. The initial three-nerve protocol, comprising sural sensory, tibial motor, and ulnar sensory and motor studies, achieved an AUC of 0.916, with 80.5% sensitivity and 89.6% specificity. Adding contralateral ulnar sensory testing increased the AUC only marginally to 0.923 and reduced sensitivity to 76.8%.
Conclusion:
The three-nerve protocol provided a favorable balance between sensitivity and specificity. These findings support a stepwise approach beginning with unilateral sural, tibial, and ulnar studies, followed by contralateral testing when needed to increase diagnostic confidence.
