Evaluation of Gastrocnemius Spasticity With Shear-Wave Elastography in Children with Cerebral Palsy after Botulinum Toxin Injection: Defining A Proper Position for Measurement

Abstract

Aim: Cerebral Palsy (CP) is the most common neuromuscular disorder in children and it is characterized by a dysfunction in movement and posture. Botulinum toxin injection is a treatment method used for muscle spasticity in patients with CP. Elastography is a new method which is used for measuring muscle stiffness. This study aims to evaluate the gastrocnemius muscle stiffness in cerebral palsy patients before and after botulinum toxin injection by using the elastography method and contribute to the establishment of a treatment algorithm with a proper position for measurement.Materials and Method: The participants of this study were chosen from the patients of our hospital’s orthopaedics and traumatology department. Among the patients on whom botulinum injection to gastrocnemius muscle was planned, 30 patients were randomly selected. Elastography of both gastrocnemius muscles were taken before the injection of botulinum toxin, in the third week and third month after the injection. Simultaneously with the elastography, Modified Ashworth Scale (MAS) values were noted. In hemiparetic patients, contralateral legs were taken as the control group.Results: The elastographic values of the medial head of gastrocnemius when the knee is in extension and ankle in passive dorsiflexion, were found to be statistically significantly related (p<0.05) to the MAS values before botulinum toxin injection, third week and third month post-injection.Conclusion: Stiffness due to spasticity in gastrocnemius muscle in CP patients was demonstrated through elastographic evaluation. A correlation was found between clinical MAS values. The most proper position was in which the knee is fully extended and the ankle is passively dorsiflexed. Elastographic measurements may be able to be used in these patients as a method of diagnosis in the future and it will help to assess the effectiveness of the treatment after the injection of botulinum toxin.