The anatomy of the cutaneous branches of the cervical plexus and its clinical significance - The Great Auricular Nerve. A systematic review with meta-analysis.

BACKGROUND: The great auricular nerve (GAN) is the largest cutaneous branch of the cervical plexus, playing a crucial role in head and neck surgeries, including aesthetic procedures, migraine treatment, and parotid gland interventions. Despite its clinical importance, anatomical descriptions of GAN remain inconsistent across studies.

MATERIALS AND METHODS: This systematic review aims to provide a comprehensive, evidence-based analysis of GAN anatomy. A systematic search was conducted across major electronic databases to identify original studies reporting morphometric and branching data on GAN. Studies that were review articles, case reports, letters to the editor, conference abstracts, or performed on animals were excluded. The methodological quality of the included studies was assessed using the Anatomical Quality Assurance (AQUA) Tool developed by the Evidence-Based Anatomy Working Group.

RESULTS: This review was registered in the PROSPERO database, ID CRD420251005988. This part of the review included 21 studies, encompassing 745 dissected GANs (512 cadaveric and 233 intraoperative observations). During its course, GAN divides into multiple branches supplying the mastoid region, posterior two-thirds of the auricle, lobule, parotid gland, and overlying skin. Several anatomical landmarks were identified for GAN localization, and their distances to notable parts of GAN anatomy were recorded and analyzed.

DISCUSSION AND CONCLUSIONS: This review provides the most comprehensive synthesis of GAN anatomy to date. Given its high clinical relevance, especially in surgical procedures and nerve grafting, precise anatomical knowledge is essential to minimize iatrogenic injuries. However, due to variability in study methodologies and reporting quality, further high-quality anatomical studies are needed to refine surgical guidelines.