Ultrasonographic analysis of the calves for efficient botulinum toxin type A injection.

[BACKGROUND] Large calves are considered unattractive. Botulinum toxin type A (BoNT-A), acting as a neurotoxin that reduces muscle contraction, is widely used in calf contouring. However, there lacks detailed anatomical data to guide clinical injection.

[OBJECTIVES] This study aims to use ultrasonography to provide depth information of the calf muscles and determine the morphological types of the gastrocnemius muscle.

[METHODS] Ultrasound scanning was performed at six sites on 40 Chinese adults. A real-time ultrasound scannerwas used to detect the depth of the gastrocnemius muscle and the soleus muscle.

[RESULTS] The thickness of the gastrocnemius muscle and the soleus muscle was measured. The depth from the skin to the surface, the middle, and the bottom of the gastrocnemius muscle was measured. The morphology of gastrocnemius muscle was classified into four different types under ultrasound according to the muscle bulge pattern.

[CONCLUSION] This study took ultrasonic measurements of Asian calves to guide accurate and effective BoNT-A injection in real clinical practice.