The Posterior Triangle and Posterior Muscles of the Neck in 3-Dimensions: Creating a Digital Anatomic Model Using...

The posterior cervical triangle houses an important nodal basin in the spread of several cancers in the head and neck, particularly cutaneous malignancies of the scalp. A safe and effective Level V neck dissection necessitates thorough understanding of the neurovascular structures housed within the region. Conventional 2D anatomical representations offer insights into the named structures, but fall short in illustrating the spatial relationships crucial in surgery. Here, we aim to develop an anatomically-precise 3D virtual model of the posterior cervical triangle and its constituent structures.

Musculature and neurovasculature were segmented from the computerized tomography (CT) angiogram of a healthy 29-year-old female. Literature review of cadaveric studies was performed to identify the most common variants, relevant surgical relationships, and usual dimensions of structures contained in the model. Structures unable to be visualized on imaging were created de novo using data obtained in the literature review. A medical illustrator then used this data to develop a 3D anatomical model using ZBrush.

The musculature (sternocleidomastoid, trapezius, omohyoid, scalenes, erector spinae, and transversospinalis muscles) and neurovasculature (spinal accessory nerve, phrenic nerve, vertebral artery, subclavian artery, and brachial plexus) were characterized through literature review. Musculature and vasculature were segmented from CT angiography while neural structures were created de novo. Both radiographic and anatomic data were used to inform the creation of a 3D model, which will be uploaded to an online database for open access viewing.

A dynamic understanding of the spatial relationships existing among structures housed within the posterior triangle of the neck is imperative when operating in the region. The development of an accurate 3D anatomical model of such structures based upon predominant variants found in the literature will supplement the education of practicing and aspiring head and neck surgeons.