Gait Alteration in Cervical Spondylotic Myelopathy Elucidated by Ground Reaction Forces

Study Design. Prospective cohort study. Objective. Analyze GRF parameters in cervical spondylotic myelopathy (CSM) patients to elucidate gait alterations as compared with healthy controls. Summary of Background Data. During the human gait cycle, the magnitude and direction of the force each foot imparts on the ground varies in a controlled fashion to propel the body's center of mass forward. Alterations in GRF patterns can both point to subtle gait disturbances and explain altered gait patterns such as that seen in CSM. Methods. Thirty-two patients with symptomatic CSM who have been scheduled for surgery, along with 30 healthy controls (HC), underwent clinical gait analysis a week before surgery. Vertical GRF parameters and force magnitude and timing at various points of the gait cycle (i.e., heel contact, maximum weight acceptance, mid-stance, and push off) were analyzed and compared between groups. Results. Increased heel contact (CSM: 60.13% vs. HC: 27.82% of body weight, BW, P = 0.011), maximum weight acceptance (CSM: 120.13% vs. HC: 100.97% of BW, P = 0.016), and diminished push off (CSM: 91.35% vs. HC: 106.54% of BW, P = 0.001) forces were discovered in CSM patients compared with HC. Compared with controls CSM patients had delayed heel contact (CSM: 9.32% vs. HC: 5.12% of gait cycle, P = 0.050) and earlier push off (CSM: 54.96% vs. HC: 59.0% of gait cycle, P = 0.050), resulting in a shorter stance phase. Conclusion. This study reinforces how CSM patients commonly exhibit altered gait patterns, but also uniquely demonstrates the increased heel-contract and maximum weight acceptance forces, diminished toe-off forces, and the shorter stance phase to absorb the BW load. When examined from a global perspective, these altered GRF parameters reflect the difficulty CSM patients have with catching their center of mass during heel-contact to avoid falling and with subsequently propelling themselves forward.