Quantitative Functional Assessment of Patients Undergoing En Bloc Vertebrectomy for Spinal Tumors: A Multi-Segment Motion Analysis Study

Objectives: Spinal tumors often require complex surgical treatments, in particular en bloc vertebrectomy, and a pre-operative kinematics and functional assessment of the spine could be advised to improve surgical outcomes and patients’ quality of life. However, established protocols for stereophotogrammetry-based gait analysis are not available. This study aims at evaluating the feasibility of an experimental protocol for multi-segment trunk and spine kinematics in patients scheduled for en bloc vertebrectomy. Methods: Ten patients and ten age- and sex-matched healthy controls underwent full-body gait analysis using an established marker-set able to track the lower limbs, pelvis, thorax, shoulders, and five spine line segments. The participants completed static double leg standing, barefoot level walking, and elementary trunk movements. A preliminary within-session repeatability assessment in two individuals (one representative patient and one healthy participant) was performed (root mean square error smaller than 10% of ROM; intra-class correlation coefficients > 0.8). Results: Compared with controls, patients affected by spinal tumors showed slower gait, shorter stride length, smaller ROM at the pelvis and thorax, and reduced frontal-plane mobility between spine line segments, but physiological lower-limb joint kinematics. During elementary movements, patients exhibited reduced trunk ROM in the anatomical plane of motion, particularly at a central spine segment, and smaller pelvic mobility in axial rotations. Conclusions: The results of this study support the feasibility of the proposed protocol for gait analysis in the rare clinical population of patients affected by spinal tumors and provide descriptive functional information that may complement conventional pre-operative clinical and imaging assessments.