Cadaveric study of methods for subscapularis muscle needle insertion

Area of Science:

• Anatomy
• Medical Procedures
• Neurology

Background:

• Accurate needle insertion into the subscapularis muscle is crucial for procedures like electromyography, botulinum toxin injections, and phenol nerve blocks.
• Evaluating different needle insertion techniques is essential for optimizing procedural success and patient outcomes.

Purpose of the Study:

• To compare the accuracy of three distinct needle insertion methods for targeting the subscapularis muscle.
• To determine the most effective approach for specific clinical applications, including electromyography, botulinum toxin injection, and phenol nerve block.

Main Methods:

• Three needle insertion techniques were assessed using cadaver injections.
• Procedures were performed by a physician certified by the American Board of Electrodiagnostic Medicine.
• An anatomist, blinded to the insertion method, dissected the cadavers to evaluate accuracy.

Main Results:

• The posterior axillary approach demonstrated superior effectiveness for subscapularis muscle needle insertion compared to medial scapular and superior scapular approaches.
• None of the evaluated approaches proved ideal for subscapular nerve injection.

Conclusions:

• The posterior axillary approach is recommended as the optimal method for subscapularis muscle needle insertion for electromyography and botulinum toxin injections.
• Accurate subscapular nerve injection is technically difficult regardless of the insertion approach utilized in this study.