A prospective analysis of magnetic resonance imaging findings in patients with sciatica and lumbar disc herniation : Correlation of outcomes with disc fragment and canal morphology

• Published in: Spine (Philadelphia, Pa. 1976) Pa. 1976), 1997-07, Vol.22 (14), p.1650-1660
• Main Authors: CARRAGEE, E. J, KIM, D. H
• Format: Article
• Language: English
• Subjects: Adult; Aged; Biological and medical sciences; Diseases of the osteoarticular system; Diseases of the spine; Female; Follow-Up Studies; Humans; Intervertebral Disc Displacement - diagnosis; Intervertebral Disc Displacement - pathology; Intervertebral Disc Displacement - surgery; Investigative techniques, diagnostic techniques (general aspects); Lumbar Vertebrae; Magnetic Resonance Imaging; Male; Medical sciences; Middle Aged; Osteoarticular system. Muscles; Prospective Studies; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Regression Analysis; Sciatica - diagnosis; Sciatica - surgery; Sciatica - therapy; Single-Blind Method; Spinal Canal - pathology; Treatment Outcome
• ISSN: 0362-2436; 1528-1159
• DOI: 10.1097/00007632-199707150-00025

A two-part observational study. In Part 1, consecutive lumbar magnetic resonance imaging scans in patients with sciatica meeting enrollment criteria were prospectively and blindly analyzed by a set protocol. In Part 2, further clinical findings at the time of the magnetic resonance imaging were obtained by retrospective chart review and outcome assessment done at follow-up of more than 2 years. To determine the quantitative magnetic resonance findings of disc and canal measures in patients with sciatica and to analyze the predictive values of these magnetic resonance imaging and clinical variables on outcomes. Part 1: Consecutive patients with a primary diagnosis of sciatica who came to lumbar magnetic resonance imaging were enrolled, and magnetic resonance imaging dimensions of discs and canal at the herniated level were collected. Part 2: Of 186 patients in Part 1, 135 were followed for more than 2 years; 87 were treated conservatively, and 48 were treated surgically. Outcomes were judged on satisfaction, activity level, medication intake, and reported pain at follow-up (mean, 2.6 years). Part 1: Wide ranges of disc and canal measurements were seen in all parameters. Significant differences in all magnetic resonance parameters were noted between male and female patients. Men had proportionately greater canal compromise by the affected disc than women. Positive sciatic tension signs and short duration of symptoms correlated with large disc herniation. Right-sided symptomatic herniations were usually larger than left. Part 2: At follow-up, predictors of outcome were determined independently for the surgery and the nonoperative groups. In the nonoperative group, a shorter duration of sciatica was the most significant predictor of a good outcome (P = 0.0018). Moreover, a duration of symptoms less than 6 months, no involvement with litigation, and younger age were also correlated with a favorable outcome. The only magnetic resonance parameter associated with good outcome was a small ratio of disc hemiarea to remaining canal hemiarea (P = 0.045). For the surgical group, a larger anteroposterior disc length was the most significant independent predictor of a positive outcome (P < 0.0001). Larger ratios of disc area to canal area are also significantly associated with good outcomes (P < 0.0001), as are large disc areas and small remaining canal areas. Large right-left canal widths and small disc widths are also identified as predictors of a favorable outcome. Of