Nerve root pressure in lumbar disc herniation.
METHODS
The contact pressure between the nerve root and lumbar disc herniation was measured and compared with clinical features.


OBJECTIVE
To assess levels of actual compression to the nerve root in clinical cases.


BACKGROUND
Actual levels of pressure to the nerve root of lumbar disc herniation in clinical cases is unknown.


METHODS
The study was performed on 34 patients who had lumbar disc herniation. All of them had been treated by open discectomy. After laminotomy, nerve root pressure was measured by inserting a transducer between the nerve root and the disc herniation. The magnitude of pressure was compared with clinical features.


RESULTS
Nerve root pressures before discectomy were varied from 7 mm Hg to 256 mm Hg (mean, 53 mm Hg). After discectomy, the contact pressure was 0 mm Hg in all cases. There were no significant correlations between the magnitude of nerve root pressure and limits to the degree of straight leg raising, duration of symptoms, and age of the patients. However, the magnitude of the pressure in patients with neurologic deficits and trunk list was significantly higher than in the absence of these findings.


CONCLUSIONS
The contact pressure exerted by lumbar disc herniation on the nerve roots was recorded during surgical intervention, and the mean pressure was 53 mm Hg. The magnitude of nerve root pressure was not correlated with the degree of straight leg raising, but with the severity of neurologic deficits.
Takahashi
K
K
Department of Orthopaedic Surgery, Saitama Medical School, Japan.
Shima
I
I
Porter
R W
RW
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D017586:Diskectomy; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D007405:Intervertebral Disc Displacement / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D007866:Leg / Q000502:physiology; D008159:Lumbar Vertebrae / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000473:pathology / Q000503:physiopathology; D010147:Pain Measurement; D011187:Posture; D011312:Pressure; D011446:Prospective Studies; D012585:Sciatica / Q000503:physiopathology; D013117:Spinal Cord Compression / Q000473:pathology / Q000503:physiopathology*; D013126:Spinal Nerve Roots / Q000473:pathology / Q000503:physiopathology*