title: MRI-demonstrated outcome of subchondral stress fractures of the knee after treatment with iloprost or tramadol: observations in 14 patients.
abstract: OBJECTIVE
  To investigate the outcome of subchondral stress fractures (SSF) of the knee after treatment with the prostacyclin analogue Iloprost or the opioid analgesic Tramadol.
  
  
  METHODS
  Case series/retrospective review.
  
  
  METHODS
  Tertiary care center.
  
  
  METHODS
  Fourteen patients with at least a single subchondral stress fracture of the knee, surrounded by bone marrow edema, visible on T1-weighted and short tau inversion recovery magnetic resonance images.
  
  
  METHODS
  Nine patients had been treated with oral Iloprost (group 1; 11 SSF) and 5 patients with Tramadol (group 2; 5 SSF) for 4 weeks in the course of a double-blind, randomized clinical trial. MR images were obtained at baseline (1 day before the start of treatment), after 3 months, and after 1 year.
  
  
  METHODS
  SSF volumes and their rates of change between baseline and follow-up examinations, as determined on T1-weighted images by computer-assisted quantification.
  
  
  RESULTS
  After three months, the SSF volumes had decreased by a median of 42.2% in group 1 and increased by a median of 2.2% in group 2 (P = 0.008). After 1 year, the median decrease in SSF volumes was 100.0% in group 1 and 65.7% in group 2 (P = 0.017).
  
  
  CONCLUSIONS
  This small case series suggests that healing of SSF is more pronounced after Iloprost treatment.
authors.affiliation: Department of Radiology, Medical University of Vienna/Vienna General Hospital, Vienna, Austria. marius.mayerhoefer@meduniwien.ac.at
authors.forename: Marius E
authors.initials: ME
authors.lastname: Mayerhoefer
authors.forename: Josef
authors.initials: J
authors.lastname: Kramer
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Breitenseher
authors.forename: Cornelia
authors.initials: C
authors.lastname: Norden
authors.forename: Anosheh
authors.initials: A
authors.lastname: Vakil-Adli
authors.forename: Siegfried
authors.initials: S
authors.lastname: Hofmann
authors.forename: Roland
authors.initials: R
authors.lastname: Meizer
authors.forename: Harald
authors.initials: H
authors.lastname: Siedentop
authors.forename: Franz
authors.initials: F
authors.lastname: Landsiedl
authors.forename: Nicolas
authors.initials: N
authors.lastname: Aigner
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000627:therapeutic use*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D017102:Fracture Healing / Q000187:drug effects*; D015775:Fractures, Stress / Q000188:drug therapy* / Q000473:pathology; D006801:Humans; D016285:Iloprost / Q000627:therapeutic use*; D007718:Knee Injuries / Q000188:drug therapy* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014147:Tramadol / Q000627:therapeutic use*; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000627:therapeutic use*
chemical_list: D000701:Analgesics, Opioid; D014665:Vasodilator Agents; D014147:Tramadol; D016285:Iloprost