Objective:

To determine how MTV of the biceps brachii affects proprioceptive performance during arm position matching (APM) and arm movement matching (KIN) tasks in healthy adults.

Background:

Muscle tendon vibration (MTV) has been widely used as a neurophysiological technique in the study of proprioception. Prior studies have shown that MTV can distort and induce perception of limb movement. MTV has also been trialed as a rehabilitation tool for proprioceptive impairments. However, the impact of MTV on proprioception has not previously been quantified using robotic assessment which allows for greater precision when assessing effects of MTV on proprioception.

Design/Methods:

Twenty-eight healthy adults performed APM and KIN tasks using a Kinarm robot. Each task was performed under two counterbalanced conditions, MTV of the dominant biceps brachii “ON”/”OFF”. Parameters analyzed included Absolute Error (AbsError), Variability (Var), Contraction/Expansion ratio (ConExp), Shift, Reaction Time (RT), Initial Direction Angle (IDA), Path Length Ratio (PLR), and Peak Speed Ratio (PSR). Paired t-tests, 95% confidence intervals (CI), and Cohen’s d quantified vibration effects.

Results:

In the APM task, MTV increased error and variability (AbsErrorXY Δ = 0.010 m, p = 0.002; VarXY Δ = 0.007 m, p = 0.001) in matched positions and induced a perceived expansion of the workspace (ConExpXY Δ = 0.21, p 0≤ .001). In the KIN task, MTV resulted in increased spatial (IDA Δ = 0.069 rad, p < 0.001; PLR Δ = 0.107, p < 0.001) and temporal (RT Δ = 0.031 s, p < 0.001; PSR Δ = 0.161, p < 0.001) errors in matching limb movement. 

Conclusions:

This study demonstrates that MTV disrupts proprioception in healthy adults, affecting static (APM) and dynamic (KIN) domains. The Kinarm provides a reproducible approach to identify domain-specific proprioceptive effects of MTV, informing future work on the use of MTV as a neurorehabilitation technique after stroke and other neurological disorders.