Beyond Arm Capacity in Chronic Stroke: Evaluating Paretic Arm Non-Use Through Arm Efficiency-A Cross-Sectional Study

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomechanics

Background:

• Post-stroke, paretic arm use depends on capacity (ability) and potentially efficiency (effort).
• Two models, capacity and efficiency, predict arm selection when both limbs are capable.
• The capacity model favors the paretic arm, while the efficiency model selects the most economical option.

Purpose of the Study:

• To numerically determine if capacity or efficiency best predicts paretic arm use in daily activities.
• To compare the predictive power of the capacity and efficiency models.

Main Methods:

• Numerical simulations were conducted using both capacity and efficiency models.
• The Bayesian Information Criterion (BIC) was used to compare model performance.
• Clinical and accelerometric data from 30 chronic stroke patients were analyzed.

Main Results:

• The efficiency model demonstrated superior prediction of arm use compared to the capacity model (BIC: -66.95 vs -5.89).
• The efficiency model showed a lower root mean square error (0.26 vs 0.72), indicating better fit.

Conclusions:

• Arm efficiency is a critical factor in understanding paretic arm non-use after stroke.
• Personalized rehabilitation strategies can be developed by assessing individual arm efficiency.