Ultrasound imaging of upper extremity spastic muscle post-stroke and the correlation with function: A pilot study.

Background: With increased practice of real-time ultrasound imaging in the physical therapy profession, it is essential to evaluate the utility of its use post stroke.

Objective: Evaluate relationship of spastic brachialis muscle architectural parameters with clinical measures of upper extremity function and spasticity.

Methods: Eleven post stroke individuals with spasticity of the upper limb had their brachialis muscle pennation angle and fascicle length measured in the affected and unaffected upper arm, at rest. Involved side upper extremity Fugl-Meyer, Modified Ashworth Scale, and grip strength were collected and compared to muscle architectural parameters of affected and unaffected brachialis muscles.

Results: Affected side brachialis pennation angle was significantly greater than the unaffected side, and affected fascile length was significantly shorter than the unaffected side. Function levels were found to be significantly higher in those with greater fascile lengths and lower pennation angles. Higher Fugl-Meyer scores of the affected upper extremity were inversely correlated with lower Modified Ashworth Scale scores.

Conclusions: An objective method of quantifying spasticity can assist in determining if functional gains made post stroke are due to compensations in movement, or due to physiological changes. Ultrasound imaging may be used as an alternative to the Modified Ashworth score to quantify muscular parameters in spastic muscles post stroke.