MAGNETIC RESONANCE IMAGING PATHOLOGICAL EVIDENCE IN PATIENTS WITH LOW BACK PAIN IN SOUTHWEST NIGERIA

Low back pain, a condition that affects many individuals worldwide during their lifetime is receiving increasing attention due to the attendant chronic disability, absenteeism from work, loss of earning power, loss of quality of life and finances. Recently focus has been on the rising prevalence and search for steps to address low back pain risk factors now known to be modifiable. For the evaluation of low back pain, magnetic resonance imaging (MRI) has emerged as the imaging modality of choice. To determine the prevalence and distribution of lumbosacral spine discs, osseous, ligamentum flavum and facet joint changes evaluated by MRI. And to further understand the lumbosacral spine biomechanics of MRI-related disco-osseous abnormalities among native African population with low back pain. This was a retrospective study. University College Hospital, Ibadan, Nigeria. The Lumbosacral spine T1W and T2W sagittal and axial images and post gadolinium contrast images generated using a low field MRI scanner and body surface coil, in patients with low back pain, were evaluated in line with pre-defined spinal changes. There were a total of one hundred and eight low back pain patients who had Magnetic resonance imaging between March 2015 and August 2016 in this study with a mean age of 49.9 years and a range of 8 to 77 years. There were 28(25.9%) patients aged 50 - 59 years; this age bracket had the highest number while those aged 20 years and below were 3.7%. In all, 80(74.1%) subjects had chronic low back pain. Abnormal Magnetic resonance findings were reported in 96.3%. Multiple disc affectation was seen in 75.3%; disc bulge (79.8%) was the commonest disc findings followed by dehydration in 74.0%. The L4/5 discs were commonly affected in disc dehydration in 59(76.6%) cases, anterior herniation in 22(61.1%) cases, ventrolateral herniations in 9(81.8%) cases, nerve root compression in 21(60%) cases, facet joint hypertrophy in 17/24(70.8%) cases and spinal canal stenosis in 32/47(68.1%) cases. Vertebral end plate changes occur mostly at L4 and L5 (74% at each level). This study has shown that Magnetic Resonance Imaging changes in low back pain involved multiple discs and multilevel osseous pathologies, however, disc abnormalities are predominant. The L4-5, L5-S1 disc levels and L4 vertebra body were the most commonly affected sites among a native African population.