title: Prospective Randomized Controlled Trial of Hindfoot and Ankle Fusions Treated With rhPDGF-BB in Combination With a β-TCP-Collagen Matrix.
abstract: BACKGROUND
  Ankle and hindfoot arthrodesis is often supplemented with autograft to promote bony union. Autograft harvest can lead to increased perioperative morbidity. Purified recombinant human platelet-derived growth factor BB homodimer (rhPDGF-BB) has stimulated bone formation in mandibular defects and hindfoot fusion. This randomized controlled trial evaluated the efficacy and safety of rhPDGF-BB combined with an injectable, osteoconductive beta-tricalcium phosphate (β-TCP)-collagen matrix versus autograft in ankle and hindfoot fusions.
  
  
  METHODS
  Seventy-five patients requiring ankle or hindfoot fusion were randomized 5:1 for rhPDGF-BB/β-TCP-collagen (treatment, n = 63) or autograft (control, n = 12). Prospective analysis included 142 autograft control subjects from another clinical trial with identical study protocols. Standardized operative and postoperative protocols were used. Patients underwent standard internal fixation augmented with autograft or 0.3 mg/mL rhPDGF-BB/β-TCP-collagen. Radiologic, clinical, and quality-of-life outcomes were assessed over 52 weeks. Primary outcome was joint fusion (50% or more osseous bridging on computed tomography) at 24 weeks. Secondary outcomes included radiographs, clinical healing status, visual analog scale pain score, American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Scale score, Foot Function Index score, and Short Form-12 score. Noninferiority P values were calculated.
  
  
  RESULTS
  Complete fusion of all involved joints at 24 weeks as indicated by computed tomography was achieved in 53 of 63 (84%) rhPDGF-BB/β-TCP-collagen-treated patients and 100 of 154 (65%) autograft-treated patients (P < .001). Mean time to fusion was 14.3 ± 8.9 weeks for rhPDGF-BB/β-TCP-collagen patients versus 19.7 ± 11.5 weeks for autograft patients (P < .01). Clinical success at 52 weeks was achieved in 57 of 63 (91%) rhPDGF-BB/β-TCP-collagen patients and 120 of 154 (78%) autograft patients (P < .001). Safety-related outcomes were equivalent. Autograft controls had 2 bone graft harvest infections.
  
  
  CONCLUSIONS
  Application of rhPDGF-BB/β-TCP-collagen was a safe, effective alternative to autograft for ankle and hindfoot fusions, eliminating the pain and morbidity associated with autograft harvesting.
  
  
  METHODS
  Level I, prospective randomized study.
authors.affiliation: Division of Orthopaedic Surgery, St Michael's Hospital and University of Toronto, Toronto, ON, Canada DanielsT@smh.ca.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Daniels
authors.affiliation: Division of Distal Extremities, Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada BC's Foot and Ankle Clinic, St Paul's Hospital, Vancouver, BC, Canada.
authors.forename: Alastair S E
authors.initials: AS
authors.lastname: Younger
authors.affiliation: Division of Distal Extremities, Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Murray J
authors.initials: MJ
authors.lastname: Penner
authors.affiliation: Division of Distal Extremities, Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Wing
authors.affiliation: Section of Orthopaedic Surgery, Department of Surgery, Calgary Orthopaedic Foot & Ankle Clinic, and Faculty of Medicine, University of Calgary, Calgary, AB, Canada.
authors.forename: Ian L D
authors.initials: IL
authors.lastname: Le
authors.affiliation: Section of Orthopaedic Surgery, Department of Surgery, Calgary Orthopaedic Foot & Ankle Clinic, and Faculty of Medicine, University of Calgary, Calgary, AB, Canada.
authors.forename: Iain S
authors.initials: IS
authors.lastname: Russell
authors.affiliation: Division of Orthopaedic Surgery, Ottawa General Hospital, and Department of Surgery, University of Ottawa, Ottawa, ON, Canada.
authors.forename: Karl-André
authors.initials: KA
authors.lastname: Lalonde
authors.affiliation: Department of Diagnostic Imaging, The Warren Alpert School of Medicine at Brown University, Rhode Island Hospital, Providence, RI, USA.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Evangelista
authors.affiliation: Wright Medical Technology, Inc, Franklin, TN, USA.
authors.forename: Jovelyn D
authors.initials: JD
authors.lastname: Quiton
authors.affiliation: Dalhousie University and Queen Elizabeth II Sciences Center, Halifax, NS, Canada.
authors.forename: Mark
authors.initials: M
authors.lastname: Glazebrook
authors.affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: DiGiovanni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D043925:Angiogenesis Inducing Agents / Q000627:therapeutic use; D000843:Ankle Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D001174:Arthrodesis / Q000379:methods*; D000077214:Becaplermin; D001672:Biocompatible Materials / Q000627:therapeutic use; D001861:Bone Regeneration / Q000187:drug effects*; D016025:Bone Transplantation; D002130:Calcium Phosphates / Q000627:therapeutic use*; D024042:Collagen Type I / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D005528:Foot / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020574:Proto-Oncogene Proteins c-sis / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed; D014182:Transplantation, Autologous; D055815:Young Adult
chemical_list: D043925:Angiogenesis Inducing Agents; D001672:Biocompatible Materials; D002130:Calcium Phosphates; D024042:Collagen Type I; D020574:Proto-Oncogene Proteins c-sis; C485817:beta-tricalcium phosphate; D000077214:Becaplermin
keywords: ankle fusion; autogenous bone graft; collagen; hindfoot fusion; nonunion; platelet derived growth factor; randomized controlled trial; rhPDGF-BB