Objective and self-perceived lower limb weakness in Parkinson's disease

Area of Science:

• Neurology
• Movement Disorders
• Parkinson's Disease Research

Background:

• Lower limb weakness is a historically recognized symptom in Parkinson's disease (PD).
• Limited understanding exists regarding the prevalence, clinical correlations, and objective muscle strength deficits associated with this symptom in PD patients.

Purpose of the Study:

• To determine the frequency of both objective and perceived lower limb weakness in individuals with Parkinson's disease.

Main Methods:

• A study involving 90 Parkinson's disease patients and 52 age-matched controls.
• Assessment included clinical/demographic data, perceived weakness, abnormal leg sensations (e.g., heaviness, fatigue, pain), and objective lower limb strength measurements (Medical Research Council scale, dynamometry, weighting machine).

Main Results:

• 69% of PD patients reported weakness/abnormal sensations versus 21% of controls.
• PD patients exhibited reduced leg pressure objectively (p=0.002).
• Perceived leg weakness and sensations correlated with gait freezing in PD patients (p=0.001), but explained only 30.4% of variance; objective strength was similar between PD groups with/without these sensations.

Conclusions:

• Perceived lower limb weakness and associated sensations are prevalent in Parkinson's disease.
• A significant dissociation exists between subjective weakness perception and objective muscle strength in the lower limbs of PD patients.
• While linked to gait freezing, the causal relationship between these sensations and Parkinson's disease progression requires further investigation.