The neck ligaments, also commonly referred to as cervical ligaments, are a series of collagenous structures that fuse bones together. Depending on the source, the ligaments may be categorized into seven to ten units, all serving different functions in the structure and motion of the neck.
A ligament is composed of fibrinous tissue and is commonly compared to a similar structure known as a tendon. Tendons primarily attach muscles to bone, whereas ligaments attach bones with one another. Both of these important skeletal structures fall under an anatomical tissue category known as connective tissues.
The neck region, or cervical region when referring to its spinal location, is a crucial area of the body as it contains nervous pathways connecting the brain to the peripheral nerves and is vital in head mobility, which aids in the body's sensing of its environment. The ligaments help support these functions, namely by keeping them working as a cohesive unit and by providing assistance in movement. Most neck ligaments provide one of these functions; however, certain ligaments may assist in both. There are primarily seven neck ligaments that fulfill important roles. These ligaments are the alar, the anterior atlantoaxial, and posterior atlantoaxial, as well as the ligamentum nuchae, anterior longitudinal, posterior longitudinal, and ligamentum flavum.
There are two vertebrae, the atlas and axis, that are key components of neck movement and are also the first two vertebrae of the spinal column. This is an important detail to recognize when orienting one's self with the location of the neck ligaments. The alar ligament is near the axis and is primarily utilized for lateral flexion and head rotation. The anterior and posterior atlantoaxial ligaments are necessary for extension and flexion, respectively. These two ligaments are in contact with both the atlas and axis.
The ligamentum nuchae spans the cervical region and functions in a neck flexion role. Another anterior and posterior pair of ligaments, the longitudinal, are neck ligaments that enable extension and flexion. As is the case with the atlantoaxial ligaments, the anterior ligament supports extension, while the posterior ligament functions in a flexion role.
The ligamentum flavum, the last of the seven most typically included neck ligaments, is utilized in neck flexion in addition to aiding in bone fusion. It is important to note that there are a number of ligaments in the sacral region of the spine that share names with those of the cervical region. Therefore, one should exercise caution in definitively concluding which ligament is being referred to.