Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P28. Does diabetes mellitus affect lumbar paraspinal muscle morphometry?

Abstract

BACKGROUND CONTEXT Changes in paraspinal muscle cross-sectional surface area (CSA) have been shown to occur in patients with chronic and acute low back pain. Numerous factors can affect muscle density; however, the relationship between metabolic disease, such as type II diabetes mellitus (DM) and lumbar paraspinal morphometry, has not been examined. Therefore, we set out to compare paraspinal CSA in diabetic patients undergoing lumbar fusion to patients without diabetes. PURPOSE To investigate the association between type II diabetes and lumbar musculature sarcopenia. STUDY DESIGN/SETTING Retrospective cohort. PATIENT SAMPLE Retrospective review of patients with degenerative spondylolisthesis undergoing single-level lumbar fusion. METHODS A retrospective review of 101 patients, who underwent posterior lumbar fusion for degenerative spondylolisthesis, was performed. Data collected included preoperative Oswestry Disability Index (ODI), SF-12 physical and mental health scores, and visual analog scale (VAS) for back pain. Utilizing standard measurement software for the iliocostalis, longissimus, multifidus, and psoas muscles, individual paraspinal muscle CSA was measured on preoperative magnetic resonance imaging (MRI). Average CSA measurements were then compared between diabetic and nondiabetic patients utilizing Student's t-test. RESULTS Thirteen patients were included in the DM group while 88 composed the nonDM group. There were no differences in age or body mass index (BMI) between the groups. There were no significant differences in preoperative ODI, VAS back pain scores, or SF-12 mental or physical health scores. Average psoas muscle CSA was not significantly different between the groups (1091.5 mm2 vs. 938.3 mm2 for nonDM vs. DM, respectively, p=.09). Iliocostalis CSA was 1145.3 mm2 and 1023.5 mm2 for the nonDM and DM groups, respectively (p=.263). The multifidus CSA was 513.4 mm2 and 478.9 mm2 for the nonDM and DM groups, respectively (p=.458). The longissimus CSA was significantly decreased in the DM group, with an average surface area of 574.8 mm2 when compared to, 724.3 mm2 for the nonDM (p=.004). CONCLUSIONS This study is the first to establish that type II DM is associated with decreased paraspinal muscle CSA, but this finding was specific to the longissimus muscle. There is increasing evidence that changes in paraspinal morphometry are implicated in the development of chronic LBP, and our findings suggest that metabolic factors may play an important role in the maintenance of paraspinal muscle balance.