title: Complications of total hip arthroplasty: MR imaging-initial experience.
abstract: OBJECTIVE
  To investigate the use of standard magnetic resonance (MR) imaging sequences with simple parameter modifications for the detection and characterization of total hip arthroplasty (THA) complications.
  
  
  METHODS
  An initial phantom study was performed with cobalt-chrome and titanium prostheses to establish the imaging parameters for a subsequent clinical study. In the clinical study, coronal and transverse MR imaging of 14 THA prostheses was performed before and after intravenous contrast material administration in 12 patients who were being considered for revision arthroplasty. The images were reviewed for evidence of juxtaarticular or periprosthetic abnormalities, patterns of contrast enhancement, and quality of periprosthetic tissue depiction.
  
  
  RESULTS
  Phantom study results showed improved periprosthetic tissue depiction with use of thin sections, increased frequency-encoding gradient strength, and fast spin-echo sequences. The clinical study results demonstrated periprosthetic abnormalities in 11 cases: mechanical loosening in two cases (including one case with an associated periprosthetic fracture); granulomatosis, eight; and infection, one. In 100% of cases, tissue depiction around the femoral component was judged to be of "diagnostic quality." Tissue depiction around the acetabular component was of diagnostic quality in five (36%) cases. In all seven surgically confirmed cases, a correct diagnosis was made preoperatively with MR imaging.
  
  
  CONCLUSIONS
  By using simple modifications to standard MR imaging sequences, diagnostic-quality MR imaging of THA complications can be performed, particularly around the femoral prosthetic stem.
authors.affiliation: Dept of Medical Imaging, Mount Sinai Hospital and the University Health Network, University of Toronto, Ontario, Canada. lwhite@mtsinai.on.ca
authors.forename: L M
authors.initials: LM
authors.lastname: White
authors.forename: J K
authors.initials: JK
authors.lastname: Kim
authors.forename: M
authors.initials: M
authors.lastname: Mehta
authors.forename: N
authors.initials: N
authors.lastname: Merchant
authors.forename: M E
authors.initials: ME
authors.lastname: Schweitzer
authors.forename: W B
authors.initials: WB
authors.lastname: Morrison
authors.forename: C R
authors.initials: CR
authors.lastname: Hutchison
authors.forename: A E
authors.initials: AE
authors.lastname: Gross
mesh_terms: D000077:Acetabulum / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D016477:Artifacts; D002858:Chromium Alloys; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D005269:Femur / Q000473:pathology; D005500:Follow-Up Studies; D015745:Granuloma, Foreign-Body / Q000175:diagnosis; D006622:Hip Prosthesis; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D019047:Phantoms, Imaging; D011474:Prosthesis Design; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000175:diagnosis; D012086:Reoperation; D013499:Surface Properties; D014025:Titanium
chemical_list: D002858:Chromium Alloys; D003287:Contrast Media; D014025:Titanium