Disc herniation is a common pathological entity. The relationship between disc prolapse magnitude and severity of symptoms is not known. Controversy exists as to the exact cause of lower back pain and the anatomical structures being irritated. Seventy-seven patients with definite and resistant lumbar disc herniation underwent discectomy under local an-esthesia. Type of disc was correlated with severity of symp-toms. Assessment of painful structures within the spinal canal was performed. Fifty-one patients had bulging disc and disc protrusion. Most patients (86.3% of those with bulging discs and 82.8% of those with protruded disc) experienced moderate or severe pain. All patients with inflamed nerve roots had se-vere radicular pain on stimulation. All patients required infil-tration of posterior elements to allow pain-free-retraction of paraspinal muscles to perform laminectomy. Greater magnitude of disc disruption does not correlate with more severe symp-toms. Inflamed structures within the spinal canal are exception-ally sensitive to stimulation. Posterior spinal elements are a cause of significant back pain.
Introduction
Herniation of the lumbar intervertebral disc is recognized as a cause of back pain and sciatica. Severity of pain is thought to be related to the extent of disc pathology and extrusion from the intervertebral position. The extent and type of lumbar disc protrusion has not been corre-lated with the severity of low back pain and sciatica. The tissues involved in the generation of low back and leg pain have not been clearly identified, although significant clarification has occurred with descriptions of sequential stimulation of spinal tissues under local anesthesia. How-ever, there was no comment on the significance of mag-nitude and type of disc protrusion in relation to the se-verity of symptoms of lower back pain and sciatica. In this study we tried to relate the extent and type of disc protrusion with the clinical severity of symptoms of lower back pain and sciatica.
Offprint requests to: M.S. El-Zahaar, 7 Gernada Street, Roxy, Heliop-olis, Cairo, Egypt ISSN 0890-6599 © 1995 Springer-Verlag New York Inc.
Materials and Methods
This series consisted of 77 consecutive patients undergo-ing lumbar discectomy. Fifty-one patients were males (66.2%) and 26 were females (33.8%). The average age of the population was 46 years, with a range from 33 to 64 years. The duration of symptoms prior to surgery ranged from 2 months to 3.4 years, with an average time to pre-sentation of 1 year and 5 months. Patient assessment included a complete history and physical examination with particular emphasis on neurological findings. In 23 patients, myelogram and computed tomography (CT) scan were occasionally performed. The rest of the pa-tients in this series, 46 out of 54 patients, had CT scan performed routinely, while 8 had magnetic resonance im-aging (MRI) examination. Patients diagnosed by discog-raphy were excluded to avoid interference of the results with the gained bulge due to dye injection into the disc with consequent increase of the intradisc pressure that may add to its bulge. Indications for surgery included severe pain not re-sponsive to 6 weeks of conservative treatment, including bed rest and analgesia; confirmation of disc protrusion by CT or myelography and even by MRI with appropriate clinical symptoms and signs; and cauda equina syn-drome. Levels of surgery were L3,..4 in 4 patients, L4_5 in 39 patients, and L5—S1 in 34 patients. Patients diagnosed with more than one disc herniation were excluded in this study to avoid combination of more than one type of prolapse (e.g., bulge, protrusion, extrusion, or sequestra-tion). Preoperative pain severity was assessed using a back pain scale that combined the symptoms of back pain and sciatica (Table 1).
Operative Technique All surgery was performed under local anesthesia [IL Patients were placed prone on the operating table and bolsters were applied beneath the chest and iliac crest. Routine prepping and draping for a midline approach to the lumbar spine was performed. Infiltration of the skin and subcutaneous tissue was performed using a combi- |
