Article

This study was performed to investigate the interrater reliability of
needle electromyographic findings and electrodiagnostic impressions among expert
electrodiagnosticians. DESIGN: Twenty-nine electromyographic recordings were
chosen for this study from a larger prospective, observational cohort of 89
consecutive subjects, who were referred for electrodiagnostic evaluation of the
lower limbs in a hospital-based spine clinic. The parent study was designed to
evaluate the utility of electrodiagnostic findings in predicting outcomes after
epidural steroid injections in lumbar radiculopathy. An unmasked, American Board
of Electrodiagnostic Medicine board-certified examiner with knowledge of the
patient's history and physical examination performed all initial
electrodiagnostic evaluations, including needle electromyographic examination of
a standardized set of six limb muscles and lumbar paraspinals representing L3
through S1 myotomes. The insertional and spontaneous activities of all muscles
were recorded as de-identified digital video files with only muscle names
visible. Motor units were not analyzed. Two independent, American Board of
Electrodiagnostic Medicine board-certified examiners, who were masked to the
patient's name, history, physical examination, and the electrodiagnostic report,
reviewed 29 study subjects' digital video files. They rated each muscle's
insertional and spontaneous activity on a standardized scoring sheet. After the
examination was scored, they also generated a diagnostic impression of no
evidence, possible evidence, or clear evidence of lumbar radiculopathy.
Interrater reliability between the unmasked examiner and the two independent,
masked examiners was assessed by Cohen's kappa statistic for electromyographic
scoring of the muscles examined and for diagnostic impression. RESULTS: The
interrater reliability was substantial (kappa >0.60) showing >60% agreement for
the scoring of most of the muscles examined. The overall diagnostic impression
showed outstanding interrater reliability (kappa >0.90) showing >90% agreement
between the unmasked and masked examiners. There were no significant differences
in the scoring between the two masked examiners. CONCLUSIONS: Needle
electromyographic assessment of lower-limb and lumbar paraspinal muscles in the
electrodiagnostic evaluation of lumbar radiculopathy is objective and highly
reliable when performed by well trained and qualified electromyographers. Masked
validation can be performed in electromyographic-based research.

Langue : ANGLAIS