A technique to identify the axillary nerve and its cutaneous branch for triceps nerve-to-deltoid nerve transfer. A case report

INTRODUCTION: Triceps nerve-to-deltoid nerve transfer requires the identification of the axillary nerve in the quadrilateral space. This may be difficult especially for residents-in-training. The senior author is a Professor of Hand Surgery at a teaching institution and has devised a new technique of identification of the axillary nerve and its cutaneous branch using surface land-marks and on-table ultrasonography. CASE REPORT: The axillary nerve and the quadrilateral space is first identified using anatomical landmarks. The ultrasound probe is the used to identify the quadrilateral space and the axillary nerve which appears as hyper-echoic oval-shaped structure. The ultrasound probe is then moved to scan the cutaneous branch of the axillary nerve as it branches-off the main nerve trunk. Finally, the cutaneous branch is traced superficially till it becomes subcutaneous. This point is marked and the skin incision is made along this marked point. During surgery, the cutaneous branch is followed retrograde to the axillary nerve in the quadrilateral space. DISCUSSION: Ultrasound guidance for localization of various nerves is now routinely done by anesthetists in the Operating Room. This localization is used for nerve blocks and in patients with brachial plexus injuries. Hence, the ultrasound machine and the expertise are already available in the operating room; and no special arrangements with the Radiology Department are needed. CONCLUSION: A technique of identification of the cutaneous branch of the axillary nerve using anatomical landmarks and ultrasonography is described. The localization is accurate and is of help in patients undergoing triceps nerve-to-deltoid nerve transfer.