Spinopelvic mobility has been associated with THA outcome. To-date spine assessments have been made quasi-statically, using radiographs, in standing and seated positions but dynamic spinopelvic mobility has not been well explored. This study aims to determine the association between dynamic (motion analysis) and quasi-static (radiographic) sagittal assessments and examine the association between axial and sagittal spinal kinematics in hip OA patients and controls. This is a prospective, IRB approved, cohort study of 12 patients with hip OA pre-THA (6F/6M, 67±10 years) and six healthy controls (3F/3M, 46±18 years). All underwent lateral spinopelvic radiographs in standing and seated bend-and-reach (SBR) positions. Pelvic tilt (PT), pelvic-femoral-angle (PFA) and lumbar lordosis (LL) angles were measured in both positions and the differences (Δ) in angles between SBR and standing were computed. All participants performed two dynamic tasks at the motion laboratory: seated maximal trunk rotation (STR) and seated bend and reach (SBR). Three-dimensional joint motion data were collected and processed by a 10-camera infrared motion analysis system (Vicon, Nexus 2.10, UK). Total axial and sagittal spine (mid-thoracic to lumbar) range of motion (ROM) were calculated for STR and SBR, respectively.Introduction
Methods