Thyroid acropachy is an uncommon manifestation of advanced autoimmune thyroid disease and includes clubbing and digital swelling with or without a periosteal reaction visible on X-ray. It is usually painless and asymptomatic and therefore noted by physicians rather than patients.
When present, acropachy is almost always associated with the ophthalmopathy and dermopathy (pretibial myxoedema) of Graves' Disease. Community studies demonstrate that around 1% of patients with ophthalmopathy from Graves' will also have acropachy.
Acropachy may be distinguished from Pulmonary Osteoarthropathy and classical clubbing by the presence of Graves' ophthalmopathy and by the asymmetric and non-laminal character of the periosteal reaction. The mechanism is not well understood but may involve an autoimmune reaction with fibroblast proliferation and glycosaminoglycan deposition.
No specific therapy for acropachy is available and usually none is required. Remission can occur in the long-term with treatment of the underlying thyroid disease. In painful cases, immunosuppresive therapy or local corticosteroid administration may be beneficial.
Fatourechi V et al. Thyroid Acropachy: Report of 40 Patients Treated at a Single Institution in a 26-Year Period The Journal of Clinical Endocrinology & Metabolism Vol. 87, No. 12 5435-5441 (2002)