title: Masquelet technique: myth or reality? A systematic review and meta-analysis.
abstract: BACKGROUND
  The induced membrane technique (IMT) or Masquelet technique, is a two-step surgical procedure used to treat pseudoarthroses and bony defects. Many authors have introduced variants to the technique. This study aims to compare the surgical variants of IMT and to evaluate its efficacy in achieving infection eradication and bone union.
  
  
  METHODS
  A systematic review was carried out following the PRISMA guidelines. PubMed and other medical databases were explored using keywords "Masquelet technique" and "induced membrane technique". Articles were included if written in English, French or Italian, dealing with IMT employed to long bones in adults, reporting at least 5 cases with a 12 months-mean follow-up. Patients' clinical features, bone defect features, aetiologies, surgical data, complications, reinterventions, union rates and infection eradication rates were searched. Fischer's exact test, chi-square test and unpaired t-test were used for the statistical analysis on the individual patient's data.
  
  
  RESULTS
  Seventeen papers met the inclusion criteria (427 patients). Among these, only 10 studies reported individual patient's data (137 cases). The union rate was 89.7% and the infections rectified in 91.1% of cases. The bone defect length ranged from 0.6 to 26 cm. The main complications were superficial (21; 4.9%) and deep surgical site infections (19; 4.4%), failure of one of the IMT steps (persistence of infections or non unions, 77, 18%), with subsequent requirement for further surgery. The surgical variants included the use of antibiotic-coated spacers, internal fixation during the first step, use of Reamer-Irrigator-Aspirator technique, iliac crest grafting, bone substitutes and growth factors. However, univariate analysis only showed a positive correlation of the need for reinterventions with poorer bone union rates (p = 0.005) and complications (p <0.001), while patients undergoing IMT because of bone infections had a higher risk of surgical complications (p <0.001).
  
  
  CONCLUSIONS
  IMT aims to achieve bone union and infection eradication, but persistence of infection or non-union was noted in 18% of cases necessitating re-interventions. This may be related to the different anatomical sites that the technique has been applied and different local and patient related conditions. We believe the choice of a surgical technique to achieve union should be tailored to the individual patient's needs. This systematic review was limited by the few studies meeting our inclusion criteria, and their high variability in data reporting, making it impossible to undertake a meta-analysis.
  
  
  CONCLUSIONS
  Further studies are needed to demonstrate the role the patients' clinical features and IMT variants have upon achieving bone union and infection eradication.
authors.affiliation: Department of Reconstructive Surgery and Osteo-articular Infections C.R.I.O. Unit, I.R.C.C.S. Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy; Università degli Studi di Milano, via Festa del Perdono 7, 20122 Milano, Italy. Electronic address: ilaria.morelli90@gmail.com.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Morelli
authors.affiliation: Laboratory of Clinical Chemistry and Microbiology, I.R.C.C.S. Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Drago
authors.affiliation: Department of Trauma and Orthopaedics, University College London Hospitals, London, UK.
authors.forename: David A
authors.initials: DA
authors.lastname: George
authors.affiliation: Department of Reconstructive Surgery and Osteo-articular Infections C.R.I.O. Unit, I.R.C.C.S. Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy; Università degli Studi di Milano, via Festa del Perdono 7, 20122 Milano, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Gallazzi
authors.affiliation: Department of Reconstructive Surgery and Osteo-articular Infections C.R.I.O. Unit, I.R.C.C.S. Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Scarponi
authors.affiliation: Department of Reconstructive Surgery and Osteo-articular Infections C.R.I.O. Unit, I.R.C.C.S. Galeazzi Orthopaedic Institute, Via R. Galeazzi 4, 20161, Milan, Italy; Università degli Studi di Milano, via Festa del Perdono 7, 20122 Milano, Italy.
authors.forename: Carlo L
authors.initials: CL
authors.lastname: Romanò
mesh_terms: D016025:Bone Transplantation / Q000379:methods*; D017102:Fracture Healing; D050723:Fractures, Bone / Q000473:pathology / Q000628:therapy*; D005599:Fractures, Ununited / Q000473:pathology / Q000628:therapy*; D006801:Humans; D007085:Ilium / Q000637:transplantation; D010019:Osteomyelitis / Q000628:therapy*; D007507:Therapeutic Irrigation / Q000379:methods*; D020858:Tissue and Organ Harvesting
keywords: Masquelet technique; bone defect; bone non-union treatment; induced membrane technique; meta-analysis; osteomyelitis; systematic review