Feng's spinal manipulation for cervical spondylosis: kinematic changes

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 motion range, coupled motion patterns, motion symmetry, motion smoothness, and motion velocity. RESULTS AND CONCLUSION: Compared with healthy controls, patients with cervical spondylosis showed significantly reduced maximal angles in lateral flexion, flexion-extension, and axial rotation (P < 0.05), and significantly increased ratios of coupled flexion-extension during lateral flexion, coupled rotation during lateral flexion, coupled lateral flexion during extension, and coupled lateral flexion during rotation (P < 0.05). After treatment, patients showed significant improvements in visual analog scale score and cervical dysfunction index (P < 0.05). Significant differences were found in maximal lateral flexion angle, lateral flexion symmetry, maximum and average lateral flexion velocity, maximal flexion-extension angle, maximum and average flexion-extension velocity, maximal rotation angle, rotation symmetry, maximum rotation velocity, and average left rotation velocity before and after treatment (P < 0.05). No significant differences were observed in coupled motion patterns before and after treatment (P > 0.05). Significant differences were found in the ratios of coupled flexion-extension during right lateral flexion, coupled rotation during lateral flexion, coupled flexion-extension during right rotation, and coupled lateral flexion during rotation before and after treatment (P < 0.05). In conclusion, patients with cervical spondylosis exhibit increased ratios of some coupled motions relative to primary motions. Feng's spinal manipulation can significantly improve clinical symptoms and effectively restore cervical motor function.

1. Introduction

Research data indicate that the incidence of cervical spondylosis increases exponentially with age, and the age of onset is significantly shifting to younger populations [1-3]. In a cross-sectional study involving 4,896 participants, the overall detection rate of cervical spondylosis in children and adolescents reached 22.9% [4]. Cervical kinematics, which studies the three-dimensional motion patterns of the cervical spine, including parameters such as range of motion, velocity, and trajectory, are important indicators for assessing cervical spine function [5-8]. Due to factors such as intervertebral disc degeneration, osteophyte formation, and ligament calcification, patients with cervical spondylosis often exhibit kinematic changes, manifested as reduced range of motion, decreased velocity, and abnormal trajectories [9-10].

Cervical coupled motion, as a biomechanical feature of multi-dimensional coordinated movement, is of significant value in revealing the biomechanical properties of the cervical spine, elucidating disease mechanisms, and optimizing diagnostic and therapeutic strategies. Studies have shown that abnormal changes in coupled motion patterns are significantly correlated with the progression of cervical degenerative changes and the degree of functional impairment [11-12]. However, in current clinical practice, researchers often focus on measuring the active range of motion of the cervical spine. Although this can effectively assess disease severity and serve as a core outcome measure for therapeutic efficacy, it generally neglects the dynamic monitoring and analysis of coupled motion parameters [13-14].

Symmetry is a commonly used parameter in cervical kinematics. In the past, researchers often used the ratio of angles at the extreme positions of cervical motion to assess symmetry. However, when the cervical spine is in a pathological state, the motion trajectory curves change. This method only focuses on the peak angles and ignores changes in other parts of the entire motion process, leading to an inability to accurately assess cervical symmetry.