Hereditary isolated metatarsophalangeal arthritis.

Objective: To describe a family with 13 members in four generations affected by early-onset isolated painful arthritis limited to the first metatarsophalangeal (MTP) joint but without evidence of generalized joint disease at follow-up.Methods: A complete family pedigree was constructed and radiographs from the affected family members and their offspring were taken. Laboratory tests including serum measurements of C-reactive protein (CRP), urate, and rheumatoid factor (RF) were performed to exclude gout and rheumatoid arthritis from the diagnosis.Results: The age at onset of first MTP joint symptoms varied from 12 to 51 years. Both females and males were affected in the four successive generations, including male-to-male transmission as well as maternal inheritance. The affected patients were often treated surgically with good pain-relieving results.Conclusion: To our knowledge, this is the first report of early-onset isolated foot metatarsal arthritis with apparent autosomal dominant inheritance.