title: Localized pigmented villonodular synovitis as a rare cause of chronic anterolateral ankle pain in an equestrienne.
abstract: An unusual case of localized pigmented villonodular synovitis of the ankle as a rare cause of chronic anterolateral ankle pain in a 16-year-old horsewoman is presented. Intra-articular nodular forms of pigmented villonodular synovitis can only be diagnosed arthroscopically, macroscopic and microscopic aspects being typical. We believe that this lesion is more likely a reactive process secondary to repetitive microtrauma rather than a true neoplasm. Our patient presented with pathology in the left ankle, the side by which one mounts and dismounts a horse, forcing, in both activities, ankle dorsiflexion. Moreover, an English saddle was used by our patient, upon which one rides with the ankle maintained in dorsiflexion. At arthroscopy, the soft-tissue mass was seen to be entrapped in the joint between the talus and the tibia at dorsiflexion of the ankle. This had caused a slowly progressive enlargement of the lesion because of fibrosis resulting from reactive inflammation associated with this repetitive microtrauma, thus causing irritation, pain, and synovitis due to impingement.
authors.affiliation: Department of Orthopedic Surgery, Hospital Arnau de Vilanova, Valencia, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Sanchis-Alfonso
authors.forename: E
authors.initials: E
authors.lastname: Villanueva-García
mesh_terms: D000293:Adolescent; D016512:Ankle Injuries / Q000150:complications* / Q000175:diagnosis; D001265:Athletic Injuries / Q000150:complications*; D002908:Chronic Disease; D012090:Cumulative Trauma Disorders / Q000150:complications* / Q000175:diagnosis; D005260:Female; D006801:Humans; D010146:Pain / Q000209:etiology; D013586:Synovitis, Pigmented Villonodular / Q000175:diagnosis* / Q000209:etiology* / Q000601:surgery