MRI Evaluation of Lumbar Disc Degenerative Disease

Abstract

Aim of the work: lumbar disc degenerative disease is most leading cause of back pain, it is the most common cause of disability at age above 45 years and 2nd most common reason for primary care physician visit. Magnetic Resonance Imaging (MRI) is the standard imaging modality for detecting disc pathology due to its advantage of lack of radiation, multi planar imaging capability, excellent spinal soft-tissue contrast and precise localization of intervertebral discs’ changes. this study aimed to evaluate the characterization, extent and changes associated with the degenerative lumbar disc disease by Magnetic Resonance Imaging. Study Design: cross-sectional and observational study. Study Sample: forty consecutive and clinically examined patients with lower back pain suggestive of lumbar disc disease. Material and Methods: 40 patients with age group between 17 and 80 years with low back pain were diagnosed on 1.5 Tesla MRI machine. The following MRI findings were noted: lumbar lordosis preserved or not, ligamentum flavum hypertrophy, facet joint arthrosis or osteophytes formation and Endplate (modic) changes, decreased disc height as compared to the upper and lower vertebral levels and loss of signals, disc bulge at different levels, Disc protrusion and disc extrusion was observed. Result: most of patient showed lossof lumbar lordosis, facet joint arthrosis, ligamentum flavum hypertrophy, Endplate (modic) changes, and osteophytes formation. Disc dehydration which is one of the earliest features of aging and disc degeneration was present in (42%) patients with the most dehydrated disc seen at L4/L5 and L5/S1. Patients with degenerative disc disease had the following disc contour abnormalities. Disc bulges (26.5%) and herniations (10.5%). Herniations were further reported as broad based herniations (9.5%), extrusions (19.0%) and the protrusions (71.4%). The most common site for bulges and herniations was L4/L5 (33.6%) and (57.1%) respectively. The most common complication of bulges and herniations was impingement of exiting nerve roots (40%) and compression of exiting nerve roots and cauda equina (47.6%) respectively. Conclusion: lumbar disc degeneration is the most common cause of low back pain. It is the most common cause of disability at age above 45 years. Plain radiograph can be helpful, but MRI is the standard imaging modality for detecting disc pathology due to its advantage of lack of radiation, multi planar imaging capability, excellent spinal soft-tissue contrast and precise localization of intervertebral discs changes.