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The prevalence is estimated at around 1-9/100,000.

Women are predominantly affected (F/M sex ratio around 4:1), with children being more likely to develop the disease than adults. Localized fibrosing scleroderma is classified into several subtypes that include morphea, generalized morphea, and linear scleroderma. Linear scleroderma tends to affect children and adolescents, while morphea is more common in adults. However, both can coexist in the same patient. First, areas of hard and dry skin develop in the hands, arms, face, or leg. Then, plaques (morphea) or wide strips (linear scleroderma) appear. Plaques are round or oval, often with a white appearance and a red rim. Wide strips mainly develop on the face, thorax, arms, and legs. In the case of facial involvement, some strips developing on the forehead may be hollow and lead to an appearance termed en coup de sabre. Linear scleroderma tends to involve the underlying fat and muscles and may lead to muscle atrophy. Because of the impact on growth, localized scleroderma can result in major facial or limb asymmetry, flexion contractures, and disability. Raynaud's phenomenon is usually absent.

The exact cause of localized scleroderma is unknown. The disease originates from an autoimmune reaction which leads to localized overproduction of collagen. Other suggested causes include genetic and infectious mechanisms.

Diagnosis is based on clinical data. A skin biopsy may help to confirm the diagnosis by revealing abnormal accumulation of collagen, thickening of the vessels walls, and the presence of white cells around the vessels. Blood tests are usually normal.

The differential diagnosis includes eosinophilic fasciitis (see this term).

Management is symptomatic and includes the use of corticoids for morphea lesions and immunosupressants for linear scleroderma. Physical therapy may be helpful to limit indurations and muscle retraction.

Prognosis is usually favorable. Localized scleroderma is only rarely life-threatening, but can severely affect quality of life, particularly in children. Linear lesions tend to persist longer than plaque lesions.