title: Ankle and subtalar synovitis in a ball-and-socket ankle joint causing posterolateral painful coarse crepitus: a case report.
abstract: A 17-year-old girl with bilateral ball-and-socket ankles reported left medial heel pain. Her left heel had gone into a varus position on tiptoeing, and a painful clunk had occurred when returning to normal standing. The clunk persisted after physiotherapy and treatment with an orthosis. Subtalar arthroscopy and peroneal tendoscopy showed mild diffuse synovitis of the ankle joint, especially over the posterior capsule, and a patch of inflamed and fibrotic synovium at the posterolateral corner of the subtalar joint. The clunk subsided immediately after arthroscopic synovectomy and had not recurred during 5 years of follow-up. We found no other reported cases of ankle and subtalar synovitis occurring in patients with a ball-and-socket ankle joint.
authors.affiliation: Resident, Department of Orthopaedics and Traumatology, North District Hospital, Sheung Shui, New Territories, Hong Kong Special Administrative Region, People's Republic of China.
authors.forename: Ka Yuk
authors.initials: KY
authors.lastname: Fan
authors.affiliation: Consultant, Department of Orthopaedics and Traumatology, North District Hospital, Sheung Shui, New Territories, Hong Kong Special Administrative Region, People's Republic of China. Electronic address: luithderek@yahoo.co.uk.
authors.forename: Tun Hing
authors.initials: TH
authors.lastname: Lui
mesh_terms: D000293:Adolescent; D000843:Ankle Joint / Q000601:surgery*; D001182:Arthroscopy; D005260:Female; D006801:Humans; D013380:Subtalar Joint / Q000601:surgery*; D013585:Synovitis / Q000150:complications / Q000601:surgery*
keywords: ankle valgus; ball-and-socket; crepitant clunk; fibular hemimelia; tarsal coalition