MRI Radiological Predictors of Requiring Microscopic Lumbar Discectomy After Lumbar Disc Herniation

• Published in: Global spine journal Vol. 10; no. 1; pp. 63 - 68
• Main Authors: Varlotta, Christopher G., Ge, David H., Stekas, Nicholas, Frangella, Nicholas J., Manning, Jordan H., Steinmetz, Leah, Vasquez-Montes, Dennis, Errico, Thomas J., Bendo, John A., Kim, Yong H., Stieber, Jonathan R., Varlotta, Gerard, Fischer, Charla R., Protopsaltis, Themistocles S., Passias, Peter G., Buckland, Aaron J.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01.02.2020; Sage Publications Ltd
• Subjects: Back pain; Back surgery; Magnetic resonance imaging; Original; lumbar spine; herniated nucleus pulposus; MRI; microscopic lumbar discectomy; surgery
• ISSN: 2192-5682; 2192-5690
• DOI: 10.1177/2192568219856345

Study Design: Retrospective cohort study. Objective: To investigate radiological differences in lumbar disc herniations (herniated nucleus pulposus [HNP]) between patients receiving microscopic lumbar discectomy (MLD) and nonoperative patients. Methods: Patients with primary treatment for an HNP at a single academic institution between November 2012 to March 2017 were divided into MLD and nonoperative treatment groups. Using magnetic resonance imaging (MRI), axial HNP area; axial canal area; HNP canal compromise; HNP cephalad/caudal migration and HNP MRI signal (black, gray, or mixed) were measured. T test and chi-square analyses compared differences in the groups, binary logistic regression analysis determined odds ratios (ORs), and decision tree analysis compared the cutoff values for risk factors. Results: A total of 285 patients (78 MLD, 207 nonoperative) were included. Risk factors for MLD treatment included larger axial HNP area (P < .01, OR = 1.01), caudal migration, and migration magnitude (P < .05, OR = 1.90; P < .01, OR = 1.14), and gray HNP MRI signal (P < .01, OR = 5.42). Cutoff values for risks included axial HNP area (70.52 mm2, OR = 2.66, P < .01), HNP canal compromise (20.0%, OR = 3.29, P < .01), and cephalad/caudal migration (6.8 mm, OR = 2.43, P < .01). MLD risk for those with gray HNP MRI signal (67.6% alone) increased when combined with axial HNP area >70.52 mm2 (75.5%, P = .01) and HNP canal compromise >20.0% (71.1%, P = .05) cutoffs. MLD risk in patients with cephalad/caudal migration >6.8 mm (40.5% alone) increased when combined with axial HNP area and HNP canal compromise (52.4%, 50%; P < .01). Conclusion: Patients who underwent MLD treatment had significantly different axial HNP area, frequency of caudal migration, magnitude of cephalad/caudal migration, and disc herniation MRI signal compared to patients with nonoperative treatment.