Diagnostic value of different neurophysiological methods in the assessment of lumbar nerve root lesions.
OBJECTIVE
To investigate the sensitivity of a combination of different neurophysiological testing methods in patients with lumbar nerve root lesions.


METHODS
A prospective study was carried out in an electrodiagnosis laboratory on 57 patients with clinically proven lumbar radiculopathies.


METHODS
On 9 patients with L4 nerve root lesions, 31 patients with L5 nerve root lesions, and 17 patients with S1 nerve root lesions, extensive electromyography (EMG), nerve conduction studies, F-wave-deviations, and somatosensory evoked potentials (SEPs) were performed.


RESULTS
In 93% of all patients, a pathological neurophysiological result was found. In L4 nerve root lesions, EMG was abnormal in 89%, dermatome SEPs were abnormal in 67%, and F-wave latencies were abnormal in 44%. In L5 nerve root lesions, a pathological result was found on EMG in 87%, in peroneus SEPs in 67%, and in F-wave latencies in 66%. In S1 nerve root lesions, the most sensitive results were from dermatome SEPs in 64%, followed by EMG in 53% and F-wave latencies in 24%. Nerve conduction study results were always normal.


CONCLUSIONS
There are segment-specific neurophysiological results. It is possible to enhance testing sensitivity by a combination of different neurophysiologic testing methods. On these grounds, we recommend a segment-specific neurophysiological "diagnosis scheme" to corroborate the clinical diagnosis in lumbar nerve root lesions.
Braune
H J
HJ
Department of Neurology, University Hospital Marburg, Germany.
Wunderlich
M T
MT
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004576:Electromyography; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000294:innervation; D009431:Neural Conduction; D010523:Peripheral Nervous System Diseases / Q000175:diagnosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013126:Spinal Nerve Roots / Q000503:physiopathology*