Robotically quantifying finger and ankle proprioception: Role of range, speed, anticipatory errors, and learning.

Area of Science:

• Neuroscience
• Rehabilitation Engineering
• Biomechanics

Background:

• Proprioception is vital for motor control and post-stroke recovery.
• Robotic devices offer advanced proprioceptive assessments, but programmable factors' impact is understudied.
• Testing parameters like range, speed, and prior exposure may alter limb proprioceptor sensitivity and assessment outcomes.

Purpose of the Study:

• To investigate the influence of programmable factors (range, speed, prior exposure) on proprioceptive acuity.
• To evaluate the Crisscross robotic proprioceptive assessment for fingers and ankles.
• To determine the clinical relevance of these factors in proprioceptive rehabilitation.

Main Methods:

• Utilized novel robotic implementations of the Crisscross assessment for fingers and ankles.
• Tested young, unimpaired participants in single sessions (N=16) and longitudinally (N=5, 15-30 sessions over 3-10 weeks).
• Analyzed proprioceptive acuity variations based on joint range of motion, movement speed, and repeated testing exposure.

Main Results:

• Proprioceptive acuity was superior in fingers compared to ankles (p < 0.01).
• Acuity improved near the extremes of the range of motion and was poorer at slower speeds due to anticipatory errors.
• Significant improvements in proprioceptive acuity were observed across multiple testing sessions (p < 0.01), but not in single sessions.

Conclusions:

• Testing range and speed significantly affect proprioceptive acuity measurements, necessitating their control in robotic assessments.
• Repeated proprioceptive testing over several days enhances acuity, demonstrating potential for therapeutic benefits in rehabilitation.
• Robotic technology can enable precise control of testing parameters for more reliable proprioceptive assessments and effective rehabilitation strategies.