Toward a Novel Phenotypic Classification of Parkinson's Disease for Rehabilitation: A Case Series

Traditional classifications of Parkinson's disease (PD), such as tremor-dominant and postural instability/gait difficulty (PIGD) types, are useful for prognosis but offer limited guidance for individualized interventions. This case series descriptively explores clinically observed movement patterns, referred to as rigid, loose, and hemi types, to illustrate how rehabilitation strategies were adapted for each case. Three individuals with PD were categorized by their predominant motor presentation and completed a three-month intensive rehabilitation program. The rigid type received gait training with visual feedback and rhythmic cueing. The loose type underwent trunk- and hip-focused strengthening combined with aerobic training to improve movement control. The hemi type received laterality-focused sensorimotor training progressing from single-joint to coordinated multi-joint movements. All participants showed improvements in gait symmetry, postural control, and motor function, with reductions in the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III and Parkinson's Disease Questionnaire-39 (PDQ-39) scores and enhanced spatiotemporal gait parameters. A movement-based perspective may serve as a practical clinical framework for considering individualized rehabilitation strategies. These findings should be interpreted as exploratory and hypothesis-generating.