Quantification of upper limb position sense using an exoskeleton and a virtual reality display

Area of Science:

• Neuroscience
• Rehabilitation Medicine

Background:

• Proprioception is crucial for skilled movement and daily activities.
• Existing proprioception assessments often require contralateral limb use or working memory.
• A novel protocol was developed to assess elbow position sense independently.

Purpose of the Study:

• To validate a new elbow position sense assessment protocol in healthy adults.
• To investigate the test-retest reliability of the developed protocol.
• To establish a foundation for assessing proprioception in stroke survivors.

Main Methods:

• A robotic exoskeleton and virtual reality system were used to quantify elbow joint position sense.
• Participants verbally indicated their arm's position relative to a virtual representation.
• Test-retest reliability was assessed using Bland-Altman analysis, ICC, and SEm over a one-week interval.

Main Results:

• The mean discrimination thresholds were 7.0 ± 2.4° and 5.9 ± 2.1° across two sessions.
• A statistically significant difference of -1.1 ± 2.2° was observed between sessions.
• The protocol demonstrated fair to good test-retest reliability, with an ICC of 0.47.

Conclusions:

• The developed protocol can objectively quantify elbow position sense in healthy individuals.
• Further validation in older adults and stroke patients is warranted.
• This method offers a promising tool for clinical and research applications in proprioceptive assessment.