Fascia | Description, Anatomy, Function, & Disease (2024)

fascia, network of connective tissue that envelops and supports the various structures and organs of the body, including the nerves, muscles, joints, tendons, and ligaments. The fascia serves an essential role in protecting and supporting the internal structures in the body, owing in particular to its ability to reduce friction between tissues and to transmit and distribute mechanical stress produced by external forces and muscle contraction.

Characteristics and types

Fascia is made up primarily of collagen, an abundant protein that constitutes about one-third of all protein in the human body and that accounts for most of the content of tendons and ligaments. Hyaluronan (hyaluronic acid), a lubricating polysaccharide occurring in the extracellular matrix, lies between each layer of fascia. The collagen and hyaluronan content renders fascia flexible and slick, allowing it to stretch with the body and creating a smooth surface for the parts of the body to glide across one another.

There are several types of fascia, which may be classified in different ways. The most common classification divides fascia into two major kinds: superficial and deep. Superficial fascia, which is located directly under the skin, is the topmost layer. It sometimes contains muscle fibers and is relatively thick in the torso and thin in the limbs. Deep fascia, which covers the musculoskeletal system, is thicker than superficial fascia and is subdivided into two types: aponeurotic and epimysial. Aponeurotic fascia serves as an additional attachment between the muscles and the bones and cartilage, helping strengthen and stabilize the body. Epimysial fascia wraps around skeletal muscles, providing protection. Visceral fascia supports organs in the trunk of the body, including the heart, stomach, and lungs. Parietal fascia lines cavities in the body. Other classifications differentiate fascia into categories such as the membranous layer of subcutaneous tissue of the abdomen, the fatty layer of subcutaneous tissue of the abdomen, and the membranous layer of perineum.

Conditions affecting fascia

The flexibility and strength of the fascia become compromised when hyaluronan loses its moisture content, causing so-called fascia adhesions, in which the fascia sticks to tissue. Fascia adhesions occur because, as hyaluronan dries out, the fascia tightens, restricting movement and causing pain. Fascia adhesion is caused primarily by sedentary lifestyle, overuse of a part of the body, or damage from injury or surgery.

Depending on where the adhesion occurs, the condition may be diagnosed by a specific name. For example, plantar fasciitis involves fascia that runs under the foot arch; plantar fibromatosis results from the formation of lumps of fascia under the foot. Dupuytren contracture affects the fascia under the skin of the hand, causing the fingers to flex permanently. Tightening of the fascia over the shoulder causes adhesive capsulitis (frozen shoulder), in which shoulder movement becomes severely restricted. In Peyronie disease, scarring of fascial tissue known as the tunica albuginea, which surrounds each testis, can lead to fibrosis and the formation of plaques that change the shape and size of the penis; a characteristic symptom of Peyronie disease is painful erection.

Compartment syndrome occurs when a compartment (a group of muscles, nerves, and blood vessels) becomes injured and swells or bleeds, preventing normal expansion of the fascia and placing pressure on the compartment. This pressure can limit blood flow and, in some cases, can cause tissue death and life-threatening complications. A weak spot in the fascia can result in a hernia, in which an organ or a muscle pushes through the fascia. Hernias may be inguinal (in the groin area), femoral (at the top of the thigh), and umbilical (near the navel). Myofascial pain syndrome is characterized by trigger points, tight spots in the fascia that are tender to the touch.

Genetic conditions can also affect the fascia. Ehlers-Danlos syndrome, for example, affects the amount of collagen in the body, limiting the ability of the fascia to support body structures. Symptoms include joint hypermobility and stretchy, fragile skin. Marfan syndrome, a genetic mutation affecting elastic fibers and fibrillin (components of connective tissue), is associated with atypical laxity of fascia. Affected persons are tall, with long extremities, and have hypermobile joints.

Treatment of fascia pain

Treatment of fascia pain generally is aimed at loosening trigger points caused by tight fascia via physical therapy, massage, and stretching. Acupuncture, foam rolling, and fascia blasting, in which a specialized tool is used to loosen the fascia, are sometimes also used to treat tight fascia. Fascia adhesions responsible for myofascial pain syndrome may require additional treatment with pain relievers and trigger point injections, in which a local anesthetic is applied to the trigger point and an anesthetic, a mixture of anesthetics, or a corticosteroid is injected into the area. (In some cases, only a needle and no medication is inserted into the trigger point to relieve tension.)