Biomechanical Changes and Weight Gain Throughout Pregnancy

Background. Low back and posterior pelvic pain are common musculoskeletal complaints during pregnancy. The biomechanical theory implies that the enlarging uterus causes the maternal center of gravity to move anteriorly causing stress on the low back. As the center of gravity shifts anteriorly, this can cause joint, muscle and fascial stresses on the body. The lumbosacral angle, weight distribution and low back pain were examined. These biomechanical measurements will be correlated with reported low back pain. As an Osteopathic physician, it is important to understand the biomechanical changes during pregnancy and their association with low back pain. This study will provide guidance in focusing Osteopathic Manipulative Treatments to the fascia and muscular attachments along the lumbosacral region that may have a contributing change in the biomechanics. Hypothesis. An increase in weight gain during the second and third trimesters of pregnancy will correlate with an increase in the sway rate, lumbosacral angle, and the percentage of body weight distribution posteriorly as the center of gravity moves anteriorly. An increase in reported low back pain during the 2nd and 3rd trimester will correlate with an increase in these biomechanical changes. Materials and Methods. Thirty pregnant ladies in at least their 2nd trimester (13-weeks) are being recruited at the Nova Southeastern University’s Osteopathic Manipulation Clinic, NSU’s Obstetrics and Gynecology Clinic, and at Red Pearl’s Prenatal Yoga Class in Fort Lauderdale, FL. In this study, a quadruple postural scale is utilized to measure body weight distribution and sway rate. The quadruple postural scale measures the participants’ weight gain and shift of weight anteriorly or posteriorly. A digital inclinometer is used to measure the lumbosacral angle. The Oswestry Low Back Pain Scale is utilized to measure the degree of reported low back pain. Ladies in the study will be measured throughout their 2nd and 3rd trimesters of pregnancy. Results and Conclusion. Preliminary (N = 22) results have shown that weight gain throughout the second and third trimesters of pregnancy increases the lumbosacral angle while the shift of body weight distribution moves posteriorly as the maternal center of gravity moves anterior. The higher degree of low back pain reported correlates with an increase in postural sway rate. Higher reports of low back pain also correlate with an increase in lumbosacral angle and shift of body weight posteriorly onto the heels. The results from 30 participants will be presented at the meeting.