Optoelectronic Study of Gait Kinematics in Sagittal Spinopelvic Imbalance.

OBJECTIVE

Degenerative processes induce loss of lumbar lordosis and anterior sagittal imbalance (ASI). Optoelectronic study provides kinematic analysis of movement and can also detect ASI. The aim of the present study was to assess gait kinematic modifications induced by ASI.

METHODS

Thirty-five healthy male volunteers were subjected to reversible ASI induced by wearing a kyphotic thermoformed thoracolumbar corset. The deformation was assessed by C7 tilt on EOS (EOS Imaging, Paris, France) full-spine views. Ten optoelectronic gait recordings were made with corset and 10 without. Gait kinematic parameters (stride length, walking speed, rhythm), gait balance parameters (center of mass braking index, stride width, double support time) and spinal sagittal balance parameters (C7T10S1, C7´S1' and spinal angles) were averaged. Adjusted analysis distinguished direct ASI impact from locomotor factors.

RESULTS

The corset-induced ASI produced +15° change in C7 tilt (P < 0.0001), -7.4° in C7T10S1 (P < 0.0001), +66.2 mm in C7´S1' (P < 0.0001), and +13.1° in spinal angle (P < 0.0001). Radiographic and optoelectronic data correlated significantly. Stride length (P < 0.0001) and rhythm (P = 0.0003) were significantly reduced, contributing to a reduction in walking speed (P < 0.0001), and strongly influencing double support time (β = -0.38; 95% confidence interval [CI]: -0.69; -0.06). Center of mass braking index was significantly reduced (P < 0.0001) and significantly influenced by ASI (β = -0.51; 95% CI: -0.78; -0.28). Stride width was significantly increased by ASI (P < 0.0001), independently of rhythm and stride length.

CONCLUSIONS

ASI induced by a kyphotic corset was detectable on the optoelectronic system, leading to significant changes in gait kinematics. Locomotor parameters were significantly reduced. Balance parameters were significantly and directly altered by ASI.