Accessory Nerve Anatomy in Anterior and Posterior Cervical Triangle: A Fresh Cadaveric Study

Area of Science:

• Anatomy
• Surgical Anatomy
• Neck Dissection

Background:

• The accessory nerve (CNXI) is vital for neck dissection.
• Understanding its anatomical variations is essential for surgical precision.

Purpose of the Study:

• To investigate the variations and normal course of the accessory nerve (CNXI) in the neck.
• To enhance the accuracy and confidence during neck dissection procedures.

Main Methods:

• Analysis of 100 neck dissections from 50 fresh cadavers.
• Detailed examination of the CNXI's course, surrounding structures, and influencing factors.
• Measurement of distances related to CNXI location at the posterior border of the sternocleidomastoid muscle (PBSCM).

Main Results:

• Observed eleven division variations of the CNXI within the anterior triangle.
• Found a statistically significant correlation (p<0.05) between subject height and CNXI location at the PBSCM.
• The ratio of distances from the mastoid apex (MAA) to CNXI at PBSCM increased with subject height.

Conclusions:

• The accessory nerve's course exhibits significant variations.
• Height is a factor influencing the accessory nerve's position in the neck.
• Surgeons should consider subject height, searching more inferiorly for the CNXI at the PBSCM in taller individuals.