title: Effect of ibandronate on spontaneous osteonecrosis of the knee: a randomized, double-blind, placebo-controlled trial.
abstract: Based on this double-blind, placebo-controlled study, ibandronate has no beneficial effect on clinical and radiological outcome in patients with spontaneous osteonecrosis of the knee over and above anti-inflammatory medication.
  
  
  BACKGROUND
  Observational studies suggest beneficial effects of bisphosphonates in spontaneous osteonecrosis (ON) of the knee. We investigated whether ibandronate would improve clinical and radiological outcome in newly diagnosed ON.
  
  
  METHODS
  In this randomized, double-blind, placebo-controlled trial, 30 patients (mean age, 57.3 ± 10.7 years) with ON of the knee were assigned to receive either ibandronate (cumulative dose, 13.5 mg) or placebo intravenously (divided into five doses 12 weeks). All subjects received additional treatment with oral diclofenac (70 mg) and supplementation with calcium carbonate (500 mg) and vitamin D (400 IU) to be taken daily for 12 weeks. Patients were followed for 48 weeks. The primary outcome was the change in pain score after 12 weeks. Secondary endpoints included changes in pain score, mobility, and radiological outcome (MRI) after 48 weeks.
  
  
  RESULTS
  At baseline, both treatment groups (IBN, n = 14; placebo, n = 16) were comparable in relation to pain score and radiological grading (bone marrow edema, ON). After 12 weeks, mean pain score was reduced in both ibandronate- (mean change, -2.98; 95% CI, -4.34 to -1.62) and placebo- (-3.59; 95% CI, -5.07 to -2.12) treated subjects (between-group comparison adjusted for age, sex, and osteonecrosis type, p = ns). Except for significant decrease in bone resorption marker (CTX) in ibandronate-treated subjects (p < 0.01), adjusted mean changes in all functional and radiological outcome measures were comparable between treatment groups after 24 and 48 weeks.
  
  
  CONCLUSIONS
  In patients with spontaneous osteonecrosis of the knee, bisphosphonate treatment (i.e., IV ibandronate) has no beneficial effect over and above anti-inflammatory medication.
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University Hospital Basel, Missionsstrasse 24, CH-4055, Basel, Switzerland, christian.meier@unibas.ch.
authors.forename: C
authors.initials: C
authors.lastname: Meier
authors.forename: C
authors.initials: C
authors.lastname: Kraenzlin
authors.forename: N F
authors.initials: NF
authors.lastname: Friederich
authors.forename: T
authors.initials: T
authors.lastname: Wischer
authors.forename: L
authors.initials: L
authors.lastname: Grize
authors.forename: C R
authors.initials: CR
authors.lastname: Meier
authors.forename: M E
authors.initials: ME
authors.lastname: Kraenzlin
mesh_terms: D000328:Adult; D000368:Aged; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D001855:Bone Marrow Diseases / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology; D004164:Diphosphonates / Q000627:therapeutic use*; D004311:Double-Blind Method; D004487:Edema / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000077557:Ibandronic Acid; D007719:Knee Joint; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010020:Osteonecrosis / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D010147:Pain Measurement / Q000379:methods; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D000077557:Ibandronic Acid