Relationship between Lower Limb Pain Intensity and Dynamic Lumbopelvic-Hip Alignment in Patients with Degenerative Lumbar Spinal Canal Stenosis: A Cross-Sectional Study

STUDY DESIGN: This cross-sectional study was conducted in a single hospital. PURPOSE: To clarify the relationship between lower limb pain intensity and dynamic lumbopelvic-hip alignment in patients with lumbar spinal canal stenosis (LSS), using a three-dimensional (3D) motion analysis system. OVERVIEW OF LITERATURE: Although it is well known that leg symptoms have a close relationship with posture in patients with LSS, the relationship under dynamic conditions, such as gait, remain unclear. METHODS: Thirty patients with LSS scheduled for spine surgery participated in this study. Lower limb pain was assessed using the Visual Analog Scale (VAS), and the patients were divided into two groups based on the mean scores (patients with scores above and below the mean were classified as the high-VAS and low-VAS groups, respectively). The kinematics of the spine, pelvis, and hip joints during gait were then measured using a 3D motion analysis system. Student paired t-tests were used to compare the angles of the spine, pelvis, and hip during gait between the two groups. RESULTS: Compared to those in the low-VAS group, the spine was significantly extended and bent toward the more painful lower limb side, and the pelvis was significantly anteriorly tilted among individuals in the high-VAS group. CONCLUSIONS: Patients with LSS experiencing severe pain in their lower limb tend to keep the spine in a more extended position, bend laterally toward the painful side, and have an anteriorly tilted pelvic posture. The dynamic spinal and pelvic alignment was closely related to the intensity of the lower limb pain.