title: Calcific tendonitis of the fibular collateral ligament.
abstract: This article describes calcific tendonitis within the fibular collateral ligament, presumably from hydroxyapatite deposition, a rare cause of acute, severe lateral knee pain. Imaging findings confirmed calcifications in an intact but thickened fibular collateral ligament with adjacent soft-tissue reaction, consistent with calcific tendonitis. Magnetic resonance imaging can appear aggressive, and therefore the findings often can be mistaken for other knee abnormalities; specifically, the presentation following a twisting injury that requires avulsion fracture or ligamentous injury be excluded. Confirmation of crystal deposition with thin-section CT is helpful when suspected on MRI because it is unequivocal in depicting calcifications and bony detail.
authors.affiliation: Department of Radiology, Cleveland Clinic Foundation, OH 44195, USA.
authors.forename: Kim
authors.initials: K
authors.lastname: Schindler
authors.forename: Patrick
authors.initials: P
authors.lastname: O'Keefe
authors.forename: Timothy
authors.initials: T
authors.lastname: Bohn
authors.forename: Murali
authors.initials: M
authors.lastname: Sundaram
mesh_terms: D002114:Calcinosis / Q000000981:diagnostic imaging / Q000473:pathology*; D017885:Collateral Ligaments / Q000000981:diagnostic imaging / Q000473:pathology*; D003937:Diagnosis, Differential; D006801:Humans; D007718:Knee Injuries / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D052256:Tendinopathy / Q000000981:diagnostic imaging / Q000473:pathology*