Fascite

Fascite, or fascitis, is the inflammation of fascia, the connective tissue that surrounds and supports muscles, groups of muscles, nerves and vessels, and that forms sheets and envelopes throughout the body. It is separate from tendinitis (inflammation of tendons) and myositis (inflammation of muscles). In some cases fascite refers to localized inflammation at a specific site, while in others it describes more widespread inflammation of fascia.

The most common form is plantar fasciitis, which affects the plantar fascia on the sole of the foot and causes heel or arched-foot pain, often worse with the first steps in the morning or after prolonged standing. Fascite can also occur in other fascia domains, such as the thoracolumbar fascia of the back or the fascia lata of the thigh; such cases typically present with localized tenderness and pain related to the affected region. Necrotizing fasciitis, by contrast, is a rare but life-threatening infection of fascia that requires urgent medical and surgical treatment.

Causes and risk factors include overuse and repetitive strain, sudden increases in activity, flat feet or high arches, obesity, and aging. Autoimmune or inflammatory conditions can contribute in some instances. Infections causing fascial inflammation are uncommon but can occur, especially when combined with skin or soft-tissue infection.

Symptoms generally involve localized pain and tenderness at the affected site, sometimes with swelling, stiffness, and limited range of motion. Diagnosis relies on clinical evaluation, supported by imaging such as ultrasound or magnetic resonance imaging to assess fascia thickness and integrity; laboratory tests may be used to exclude infection or inflammatory diseases.

Treatment is mainly conservative: rest, ice, nonsteroidal anti-inflammatory drugs, and physical therapy emphasizing stretching and strengthening of the involved area. Orthotics, proper footwear, and weight management may help in plantar fasciitis. Corticosteroid injections are used cautiously in some cases; other therapies include shock wave therapy and, rarely, surgery for refractory plantar fasciitis. Necrotizing fasciitis requires antibiotics and urgent surgical debridement. Most cases improve with appropriate management, though some may become chronic.