title: BST-CarGel® Treatment Maintains Cartilage Repair Superiority over Microfracture at 5 Years in a Multicenter Randomized Controlled Trial.
abstract: OBJECTIVE
  The efficacy and safety of BST-CarGel®, a chitosan scaffold for cartilage repair was compared with microfracture alone at 1 year during a multicenter randomized controlled trial in the knee. This report was undertaken to investigate 5-year structural and clinical outcomes.
  
  
  METHODS
  The international randomized controlled trial enrolled 80 patients, aged 18 to 55 years, with grade III or IV focal lesions on the femoral condyles. Patients were randomized to receive BST-CarGel® treatment or microfracture alone, and followed standardized 12-week rehabilitation. Co-primary endpoints of repair tissue quantity and quality were evaluated by 3-dimensional MRI quantification of the degree of lesion filling (%) and T2 relaxation times. Secondary endpoints were clinical benefit measured with WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) questionnaires and safety. General estimating equations were used for longitudinal statistical analysis of repeated measures.
  
  
  RESULTS
  Blinded MRI analysis demonstrated that BST-CarGel®-treated patients showed a significantly greater treatment effect for lesion filling (P = 0.017) over 5 years compared with microfracture alone. A significantly greater treatment effect for BST-CarGel® was also found for repair tissue T2 relaxation times (P = 0.026), which were closer to native cartilage compared to the microfracture group. BST-CarGel® and microfracture groups showed highly significant improvement at 5 years from pretreatment baseline for each WOMAC subscale (P < 0.0001), and there were no differences between the treatment groups. Safety was comparable for both groups.
  
  
  CONCLUSIONS
  BST-CarGel® was shown to be an effective mid-term cartilage repair treatment. At 5 years, BST-CarGel® treatment resulted in sustained and significantly superior repair tissue quantity and quality over microfracture alone. Clinical benefit following BST-CarGel® and microfracture treatment were highly significant over baseline levels.
authors.affiliation: Piramal Healthcare (Canada) Ltd., Laval, Quebec, Canada.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Shive
authors.affiliation: Department of Surgery, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: William D
authors.initials: WD
authors.lastname: Stanish
authors.affiliation: Department of Orthopedic Surgery, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: McCormack
authors.affiliation: School of Medicine, CEU San Pablo University, Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Forriol
authors.affiliation: University of Calgary Sports Medicine Centre, Calgary, Alberta, Canada.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Mohtadi
authors.affiliation: Department of Orthopedics, CHA-Pavillon Enfant-Jésus, Quebec, Quebec, Canada.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Pelet
authors.affiliation: Hôpital Charles LeMoyne, Greenfield Park, Quebec, Canada.
authors.forename: Jacques
authors.initials: J
authors.lastname: Desnoyers
authors.affiliation: Piramal Healthcare (Canada) Ltd., Laval, Quebec, Canada.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Méthot
authors.affiliation: Department of Epidemiology and Biostatistics, University of South Florida, Tampa, Florida, USA.
authors.forename: Kendra
authors.initials: K
authors.lastname: Vehik
authors.affiliation: Piramal Healthcare (Canada) Ltd., Laval, Quebec, Canada.
authors.forename: Alberto
authors.initials: A
authors.lastname: Restrepo
keywords: cartilage repair; chitosan; microfracture; quantitative MRI; scaffold