title: Acute calcific tendinitis of the gluteus medius: an uncommon source for back, buttock, and thigh pain.
abstract: OBJECTIVE
  This study was conducted to describe the imaging features and clinical manifestations in acute calcific tendinitis (CaT) of the gluteus medius muscle (GMe).
  
  
  METHODS
  A retrospective analysis was conducted, aimed at six patients with acute calcific tendinitis of the gluteus medius muscle (CaT-GMe), who were seen between January 2011 and December 2012. Clinical presentations, radiologic data (radiography, CT, and MRI), and laboratory reports were all subject to review.
  
  
  RESULTS
  All patients presented with pain and decreased range of motion (ROM) at the hip. Two of the six patients experienced pain in the anterolateral thigh and groin, with antalgic gait (anterior group). The other four complained of low back, buttock, and posterolateral thigh pain, accompanied by difficulty in standing and antalgic gait (posterior group). Edema within the GMe or effusion surrounding the muscle was regularly identified on MRIs. Calcific deposits were conspicuous in the gluteus medius tendon attachments to the lateral (anterior group) and superoposterior (posterior group) facets of the greater trochanter on radiography, CT, or MRI. Complete resolution of symptoms was uniformly achieved in 5-10 days with conservative management.
  
  
  CONCLUSIONS
  Acute CaT-GMe should be considered in any patient suffering lateral hip pain (with either groin or low back pain) and ROM limitation. Images of the hip characteristically show edema of the gluteus medius and calcifications lateral or superior to the greater trochanter.
authors.affiliation: Department of Radiology, Arumdaun Wooldul Spine Hospital, Ulsan, Republic of Korea. Electronic address: pncspine@gmail.com.
authors.forename: Nam Chull
authors.initials: NC
authors.lastname: Paik
mesh_terms: D000208:Acute Disease; D000328:Adult; D002081:Buttocks / Q000473:pathology*; D002114:Calcinosis / Q000150:complications / Q000175:diagnosis*; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D017116:Low Back Pain / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059352:Musculoskeletal Pain / Q000209:etiology; D011859:Radiography; D012189:Retrospective Studies; D052256:Tendinopathy / Q000150:complications / Q000175:diagnosis*
keywords: Back pain; Calcific tendinitis; Gluteus medius; Greater trochanter; Hip pain; Hydroxyapatite deposition; Reactive calcification