TITLE:
Needle Electromyography, F-Wave, and H-Reflex: A Critical Reappraisal of Their Utility in the Diagnosis of Various Sensory Symptoms in the Extremities and Spine in the Setting of Normal Neurological Examination
AUTHORS:
Reynaldo P. Lazaro, Thomas S. Eagan
KEYWORDS:
EMG, Electromyography, F-Wave, H-Reflex, Procedural Indications
JOURNAL NAME:
Open Journal of Orthopedics,
Vol.11 No.12,
December
21,
2021
ABSTRACT: Objective: Health care providers refer their
patients to electromyography (EMG)
laboratories for the evaluation of various sensory symptoms in the extremities
and spine. The procedure is usually performed in conjunction with
transcutaneous electrical stimulation of peripheral nerves and elicitation of
the F-wave and H-reflex. The present study aimed to determine the real value of
these procedures in the diagnosis of sensory symptoms in the setting of a
normal neurologic examination. Method: The EMG reports and clinical histories
of 100 patients, including 10 patients evaluated by other electromyographers,
were reviewed. The study was focused on those with normal neurological
examinations and those without histories of ongoing medical disorders and major
surgeries to the extremities and spine. Results:
All EMGs, F-wave, and H-reflex reports reviewed were normal, including those
obtained from the second procedure performed
in some patients and of those who subsequently
underwent spinal surgery. Neurologic examination in all patients was normal. Conclusion: Needle EMG, F-wave and
H-Reflex examinations are predictably normal in patients with
non-dermatomal, non-neuropathic sensory symptoms with normal neurologic
examination and without history of preexisting medical and surgical disorders. A good neurologic examination should determine the need to perform these procedures.
Our findings have important diagnostic, therapeutic, prognostic, economic and
legal implications.