Abstract: BACKGROUND: Patients with cervical spondylosis often exhibit varying kinematic abnormalities due to degenerative structural changes and biomechanical imbalances in the cervical spine. Although previous studies have compared specific kinematic parameters between healthy individuals and cervical spondylosis patients, research on coupled motions and their associated ratios remains limited.
OBJECTIVE: To investigate changes in kinematic parameters in cervical spondylosis patients before and after Feng’s spinal manipulation therapy.
METHODS: Thirty patients with cervical spondylosis and 30 healthy controls were enrolled. Participants completed three standardized motion tasks: lateral flexion, flexion-extension, and axial rotation. Three-dimensional cervical spine kinematics were quantified using stereophotogrammetry upon admission and discharge. The following kinematic parameters were analyzed: primary range of motion, coupled range of motion, coupling patterns, movement symmetry, motion smoothness, and angular velocity. Comparative analyses were conducted between healthy controls and cervical spondylosis patients as well as between pre- and post-treatment kinematic changes in patients.
RESULTS AND CONCLUSION: (1) Patients with cervical spondylosis exhibited significantly reduced maximal angular displacement compared with healthy controls during lateral flexion, flexion-extension, and axial rotation of the cervical spine (P < 0.05). Conversely, significant increases were observed in the following coupling ratios: flexion-extension during bending, axial rotation during bending, bending during extension, and bending during rotation (P < 0.05). (2) There were significant improvements in cervical spondylosis patients after treatment, with notable reductions in both Visual Analog Scale and Neck Disability Index scores (P < 0.05). Significant differences were also observed in kinematic parameters: maximal angular displacement during bending, bending symmetry, peak and mean bending velocities, maximal flexion-extension angle, peak and mean flexion-extension velocities, maximal axial rotation angles, rotational symmetry, peak rotational velocities, and mean left rotation velocity (P < 0.05). However, no significant differences were detected in coupling movement patterns (P > 0.05). Additionally, the axial rotation coupling ratio during bending, flexion-extension coupling ratio during right bending, bending coupling ratio during rotation and flexion-extension coupling ratio during right rotation showed significant post-treatment changes (P < 0.05). (3) Compared with healthy controls, patients with cervical spondylosis exhibited significantly higher coupling-to-primary motion ratios. Feng’s spinal manipulation not only markedly alleviated clinical symptoms but also effectively restored cervical spine mobility.

Key words: cervical spondylosis, kinematics, range of motion, coupled motion, three-dimensional motion capture, motion trajectory