Ultrasound-guided lateral approach for needle insertion into the subscapularis for treatment of spasticity

Abstract

Objective: To evaluate the safety and accuracy of ultrasound (US)-guided needle insertion into the subscapularis using fresh cadavers.

Design: A needle was inserted into the subscapularis of adult human cadavers under US guidance using a lateral approach from the posterior axillary fold. An anatomist dissected the cadavers to evaluate the effectiveness of this injection method.

Setting: University dissecting room.

Participants: Fresh cadavers (N=5).

Interventions: US-guided dye injections targeting the motor points of the subscapularis.

Main outcome measure: Accuracy of the injections and prevalence of complications. The presence of dye within 1.0cm of the motor points was defined as reaching the target. The injection procedure was considered a success if two-thirds of the injected dye reached the target.

Results: We did not identify any neurovascular structures at risk of injury in the injection route. All subscapularis muscles were injected successfully using the US-guided lateral approach.

Conclusions: US-guided needle insertion into the subscapularis using this lateral approach was accurate and had the minimal risk of neurovascular or lung injuries.