The Ligaments, Tendons, and Muscles of the Spine

The ligaments, tendons, and muscles of the spine have the duel responsibility of protecting and supporting it, as well as movement. Ligaments are bands of connective tissue that connect bone to bone. There are long ligaments that travel the length of the spine, such as the anterior longitudinal ligament and the posterior longitudinal ligament. There are also ligaments that bind sections of vertebral bones to the vertebral bones below them, such as the intertransverse ligament, interspinous ligament, and facet capsulary ligament . Tendons are bands of connective tissue are located on the ends of muscles, and connect muscle to bone. The muscles of the spine include back muscles and abdominal muscles that are responsible for holding the spine in the proper position, and for movements of the spine. Possible movements of the spine include flexion (forwards bending), extension (backwards bending), twisting, and sideway movements. All of these structures work together to balance the spine and to offer people a comfortable range of movement. We may experience discomfort or back pain as a result of muscular deconditioning or when one of the soft tissues become injured.

Ligaments: The ligaments connect bone to bone, and they may also link two or more cartilages or structures together. The molecular makeup of the fibrous bands or sheets of connective tissue make them resistant to being torn or broken, though they are composed partially of elastic fibers they give them some ability to stretch during movements. However, these ligaments are not designed to stretch more than 25% of their normal length, and the body will feel pain or discomfort when they are strained towards the high end of tensions that they can handle. This feedback on the body prevents against injury to these ligaments as well as other structures of the spine, such as the muscles and joints. These ligaments provide physical restriction, as well as pain feedback, against excessive movements such as hyper-flexion and hyper-extension.

Three of the most important ligaments of the spine include the anterior longitudinal ligament, posterior longitudinal ligament, and ligamentum flavum.

Anterior Longitudinal Ligament: The anterior longitudinal ligament travels the length of the spine, front top to bottom. The Anterior Longitudinal Ligament attaches to the front of each vertebrae and intervertebral disc.

The Posterior Longitudinal Ligament: The Posterior Longitudinal Ligament also runs the length of the spine, on the opposite surface of the vertebral body from the anterior longitudinal ligament. The posterior longitudinal ligament runs along the back of each vertebral body and in front of the spinal canal.

The Ligamentum flavum is also located within the vertebral foramen, where the spinal canal resides. The ligamentum flavum forms a cover over the dura mater, which is the outer layer of the spinal canal. This ligament connects under the facet joints to create a thin barrier over the posterior apertures between the interlocking vertebrae.

Other ligaments of the spine include the intertransverse ligament - which links adjacent transverse processes, and facet capsulary ligament - which forms a capsule around the facet joints. The Supraspinous ligament and Interspinous Ligament connect the spinous processes of adjacent vertebrae.

The spinal muscles are labeled according to their point of origin, insertion, and function. The muscles are categorized mainly by the movement functions they allow the spine. This is why the muscles are referred to as flexors, extensors, and rotators. The muscles are also labeled according to their general location: anterior, lateral, and posterior.