A STUDY OF PREVALENCE OF MRI FINDING IN PATIENTS WITH DEGENERATIVE DISCOVERTEBRAL LOW BACK PAIN

Low back pain is the most common musculoskeletal disease and has a high prevalence rate in community that causes a significant morbidity, mostly due to degenerative discovertebral disease. MRI is the best and noninvasive method for assessing degenerative discovertebral disease. This study was conducted to determine MRI findings in degenerative discovertebral disease. This descriptive study is done cross sectionally on 110 patients (60 men & 50 women) with the average age of 45 years that have degenerative low back pain without a history of trauma, neoplastic, inflammatory or spinal surgery. Degenerative findings including changes in signal of nuclear disk complex, size and shape of nuclear complex, intranuclear cleft, disk height, disk bulging, disk herniation, dural sac compression and osteophyte formation are analyzed and graded form zero to three based on their severity. The result shows %92.7 of patients have degenerative discovertebral findings. The most common age is 4-6 decades. Degenerative findings occur in men one decade earlier. The most common time for patients’ reference was 1-6 months after the disease commences. The most common disk level involvement is L4-L5 that affected men %82 and women %75. After that the fifth, the third the second and the first disks respectively. The most common degenerative findings are change in intranuclear cleft %58.2, change in signal of disk complex %41.6, disk height narrowing %25.9, change in shape and size of disk complex %23.2. Prevalence of degenerative discovertebral finding, except for disk herniation, increase from the first to the forth disk and then decrease partially. Dural sac compression in upper disk is mostly due to disk and then decrease partially. Dural sac compression in upper disk is mostly due to disk bulging and in lower disk because of disk herniation. Mild grading of degenerative discovertebral findings is more common than moderate or severe geading, except for changes of signal intensity of disk, intranuclear cleft and disk height narrowing whose moderate findings have greater prevalence. Thereis no sex difference in degenerative discovertebral finding. Signal intensity changes increases with age (P<0.05). Also there are increases in changes of size and shape of nuclear complex, intranuclear cleft, disk height narrowing in the first to the third disks (P<0.05). But there is no significant rise in disk herniation, disk bulging or dural sac compression with age. Increase in ostheophyet formation in the first and the second disk is seen (P<0.05). Degenerative discovertebral findings show that according to degenerative proces the first, the second, and the third disks might be categorized in one group and the forth and the fifth disks in another group.