Quantitative trunk sway analysis under challenging gait conditions in early and untreated Parkinson's disease

Introduction: Even experienced clinicians may encounter difficulties in making a definitive diagnosis in the early motor stages of Parkinson's disease (PD). We investigated whether quantitative biomechanical trunk sway analysis could support the diagnosis of PD early on.

Methods: We quantified trunk sway performance using body-worn sensors during a test battery of six challenging gait conditions in a cohort of 17 early and untreated PD patients (with evidence of reduced tracer uptake in the basal ganglia on dopamine transporter scans) and 17 age- and sex-matched healthy controls (HCs).

Results: Compared to HC, the PD group (Hoehn & Yahr ≤ 2, Unified Parkinson's Disease Rating Scale motor score: mean 13.7 ± 3.5 points) showed significant trunk rigidity in five challenging gait tasks (decreased medio-lateral direction and sway angle area). Post hoc receiver operating characteristic analysis of the significant parameters revealed excellent discrimination with high sensitivity and specificity.

Conclusion: In the early and untreated motor stages of PD, patients exhibit significant trunk rigidity during challenging gait tasks. Trunk sway motion recorded with body-worn sensors might be a useful tool to disclose a sometimes hard-to-trace cardinal motor sign of PD and support an early clinical diagnosis.