Gait adaptations and spinal curvature correlations following lumbar arthrodesis: an analytic cross-sectional study

Background Chronic low back pain is a major and growing public health concern worldwide. When conservative management fails, lumbar spinal fusion (arthrodesis) is a common surgical option. While postoperative pain outcomes have been extensively studied, the functional impact of lumbar arthrodesis on posture and gait remains poorly understood. This study aimed to analyze gait characteristics in patients following lumbar arthrodesis and to examine correlations between gait parameters and spinal curvature changes. Methods We conducted an analytic cross-sectional study including two groups: healthy participants and individuals who had undergone lumbar arthrodesis. Spinal curvatures were assessed using an optoelectronic stereophotogrammetric system, which recorded marker positions placed on a brace worn by the examiner during spinal palpation (A-palp method). Gait parameters were measured as participants walked at slow, fast, and self-selected speeds on an instrumented walkway equipped with pressure sensors. Results Thirteen participants with lumbar arthrodesis were compared with fifteen healthy controls. Significant differences were observed between groups in gait parameters, particularly stride length, stride width and foot progression angle. In healthy participants, lumbar lordosis showed correlations with several gait parameters, whereas in the arthrodesis group correlations were mainly observed with foot progression angle. Conclusions Individuals with lumbar arthrodesis demonstrated differences in selected gait parameters compared with healthy controls whereas no significant differences were observed in lumbar lordosis or thoracic kyphosis. Correlations between spinal curvature and gait parameters were mostly observed in healthy subjects, with weaker associations also observed in the arthrodesis group. Further longitudinal studies are needed to characterize gait patterns before and after lumbar arthrodesis and to determine whether these differences are related to surgery, chronic low back pain, or other patient-related factors.