Shear Wave Velocity to Evaluate the Effect of Botulinum Toxin on Post-Stroke Spasticity of the Lower Limb

• Published in: Toxins Vol. 15; no. 1; p. 14
• Main Authors: Hasegawa, Yuki, Niimi, Masachika, Hara, Takatoshi, Sakurai, Yoshihiro, Soshi, Shigeru, Udaka, Jun, Abo, Masahiro
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26.12.2022; MDPI
• Subjects: Adult; Ankle; Botulinum toxin; Botulinum toxin type A; Botulinum Toxins, Type A - pharmacology; Botulinum Toxins, Type A - therapeutic use; Dystonia; Electromyography; Evaluation; Gait; gastrocnemius medialis muscle; Humans; Joints (anatomy); Lower Extremity; Material properties; Mechanical properties; Muscle Spasticity - drug therapy; Muscle Spasticity - etiology; Muscle, Skeletal; Muscles; Neuromuscular Agents - pharmacology; Neuromuscular Agents - therapeutic use; post-stroke spasticity; shear wave velocity; Spasticity; Stroke; Stroke - complications; Stroke - drug therapy; Tendons; Toxins; Treatment Outcome; Ultrasonic imaging; ultrasound elastography; Velocity; Wave velocity; shear wave velocity; botulinum toxin type A; ultrasound elastography; gastrocnemius medialis muscle; post-stroke spasticity
• DOI: 10.3390/toxins15010014
• ISSN: 2072-6651

(1) Background: The evaluation of muscles with spasticity using ultrasound elastography has attracted attention recently, and the shear wave velocity (SWV) technique can measure the mechanical properties of tissues objectively and quantitatively. The purpose of this study was to evaluate the effect of using SWV to assess the effect of Botulinum toxin type A (BoNT-A) treatment in adult patients with post-stroke lower limb spasticity. (2) Methods: We assessed the modified Ashworth Scale, the modified Tardieu Scale, and SWV at rest and after stretching before and at 1 month after BoNT-A treatment in 10 adult participants with post-stroke lower limb spasticity. (3) Results: Significant changes in SWV of the ankle joint in maximum dorsiflexion to the extent possible (SWV stretched) were observed after BoNT-A treatment. SWV stretched was positively correlated with joint range of motion. Participants whose joint range of motion did not improve (i.e., gastrocnemius medialis muscle (GCM) extension distance did not change) had significantly more reductions in SWV stretched after BoNT-A treatment. (4) Conclusions: Our results suggest that the SWV measurements may serve as a quantitative assessment to determine the effect of the BoNT-A treatment in adult stroke patients. SWV measurements to assess GCM spasticity should consider the effects of tension, material properties and activation level of muscles. The challenge is to measure SWV with matching limb positions in patients without contractures.