The Relationship between Lumbar and Thoracic Curves with Body Mass Index and Low Back Pain in Students of Zahedan University of Medical Sciences

Epidemiological evidence shows that low back pain is a multi-factorial problem. There may be an abnormality in spinal curves or Body Mass Index (BMI) above 25 kg mG2 was correlated to low back pain. The purpose of this study was to evaluate the relationship between spinal curves with BMI and low back pain. In 2006, an analytical cross-sectional study was conducted in Zahedan University of Medical Sciences. Three hundred subjects were assigned to either a control group (N = 150) or a low back pain group (N = 150) through simple non probability sampling. Lumbar lordosis and thoracic kyphosis was measured using flexible ruler. The body height (m), weight (kg) and BMI were measured with a standard clinical scale. The obtained data was analyzed using Pearson correlation and independent t-test. The mean angle of kyphosis and lordosis was 23.7 7.8 and 27.9 8.9 in healthy group and 23.7 8.1 and 25 11.4 in low back pain group, respectively. No significant difference was seen between chronic low back pain and healthy subjects in terms of angle of kyphosis and lordosis (p>0.05). There was no significant relationship between thoracic kyphosis and BMI (p = 0.79). However, a significant relationship was seen between lumbar lordosis and BMI (p = 0.02). The results showed that increased BMI, changes in lumbar lordosis and thoracic kyphosis may not individually lead to low back pain. Perhaps combination of several factors resulted in low back pain occurrence.