Body Mass Index as a Predictor of Lumbar Spine Degenerative Changes: Evidence from MRI Studies in Resource-Limited Settings

Abstract

Background: Lumbar spine degenerative changes are a major cause of low back pain (LBP), a condition with high global prevalence and significant socioeconomic impact.  It is a common cause of chronic low back pain, often triggered by aging, smoking, or sedentary lifestyle. Obesity is a major contributory factor to low back pain. Elevated body mass index (BMI) and its relationship with MRI features of spinal degenerative changes in a factor resource-limited settings remains sparse. Objective: To evaluate the correlation between BMI and MRI-detected lumbar spine degenerative changes among adults with low back pain in Nnewi, Nigeria, and to contextualize findings within healthcare resource constraints. Methods: A prospective, analytical cross-sectional study was conducted among 160 adult patients presenting with LBP. BMI was calculated using standardized anthropometric measures. MRI evaluation of the lumbar spine was performed using a 1.5T scanner. Degenerative changes were assessed across disc degeneration, ligamentum flavum hypertrophy, spondylolisthesis, disc herniation, and facet joint arthropathy. Statistical analysis was performed using chi- square tests with significance set at p< 0.05 Results: The mean BMI was 27.7+- 4.9kg/m2, overweight (38.1%) and obese (31.9%) subgroups were most represented. Disc degeneration was the most prevalent degenerative change, predominantly at L4/L5 and L5/S1. Elevated BMI show statistically significantly association with disc degeneration (p=0.002) and ligamentum flavum hypertrophy (p=0.017). Other degenerative changes showed no significant association with BMI. Conclusion: Higher BMI is significantly associated with degenerative disease of the spine especially disc degeneration and ligamentum flavum hypertrophy in patients with low back pain. BMI alone does not predict all lumbar degenerative changes but could be a useful cost-effective adjunct clinical predictor for MRI evaluation in a resource limited setting.