title: Fibroma of tendon sheath located within Kager's triangle.
abstract: The formation of a fibroma of the tendon sheath, a rare, slow-growing, benign tumor, usually occurs in the upper extremities of young adult males. We present an extremely rare case of a fibroma of the tendon sheath arising adjacent to the Achilles tendon within Kager's triangle in a 41-year-old female. The patient presented with progressive pain localized to the posterior aspect of the left ankle. Complete excision and histopathologic analysis of the fibroma were performed. The patient experienced an uneventful recovery after the intervention and had no evidence of recurrence after 3 months of follow-up. Fibroma of the tendon sheath should be included in the differential diagnosis when a patient presents with a painful soft tissue mass in Kager's triangle.
authors.affiliation: PhD Student, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands.
authors.forename: Eva
authors.initials: E
authors.lastname: Jacobs
authors.affiliation: Orthopaedic Surgeon, Foot and Ankle Specialist, Research School CAPHRI, Department of Orthopedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Marianne A
authors.initials: MA
authors.lastname: Witlox
authors.affiliation: Orthopaedic Surgeon, Foot and Ankle Specialist, Research School CAPHRI, Department of Orthopedic Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands. Electronic address: j.hermus@mumc.nl.
authors.forename: Joris P S
authors.initials: JP
authors.lastname: Hermus
mesh_terms: D000125:Achilles Tendon / Q000473:pathology*; D000328:Adult; D005260:Female; D005350:Fibroma / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D019042:Muscle Neoplasms / Q000175:diagnosis* / Q000601:surgery; D013710:Tendons / Q000473:pathology* / Q000601:surgery
keywords: Achilles tendon; Kager's fat pad; ankle; giant cell tumor; panniculitis; soft tissue mass