Body-segment coordination as a new predictor of freezing of gait in people with Parkinson disease
Freezing of gait (FOG) in Parkinsons disease (PD) involves impaired integration of posture and locomotion with altered body-segment coordination. We measured coordination using gait kinematics during walking in 16 PD patients with FOG, preoperatively with and without dopaminergic medication (OFF/ON-DOPA), and postoperatively with and without subthalamic deep brain stimulation (OFF/ON-DBS). Body-segment coordination was modeled from acceleration-based intersegmental correlations across trunk, pelvis, and limbs. We tested whether coordination metrics predict individual postoperative FOG severity using LASSO regression with nested cross-validation, including preoperative demographics, clinical scores, gait and coordination metrics. Preoperatively, DOPA decreased trunk-pelvis-upper-limb coordination but increased crossed upper-lower-limbs coupling; while STN-DBS selectively increased inter-upper-limb coordination, with DOPA- and STN-DBS-induced changes being correlated. Whole-body coordination predicted individual postoperative FOG severity, with the most important couplings being the trunk-pelvis and pelvis-lower-limb. Body-segment coordination captures clinically relevant gait metrics in PD, highlighting coordination as a potential biomarker for patient stratification and treatment response.