title: Upper and lower extremity reconstructive applications utilizing free flaps from the medial genicular arterial system: A systematic review.
abstract: BACKGROUND
  Free flaps derived from the medial genicular artery (MGA) system, including the medial femoral condyle (MFC) and medial femoral trochlear (MFT) flaps, are potential reconstructive options to address upper and lower extremity bony pathology. Our primary aim was to comprehensively search the literature to describe the spectrum of pathology treated with these flaps, and to assess patient outcomes to improve our understanding of expected union and complication rates.
  
  
  METHODS
  Following PRISMA guidelines, a systematic review using Pubmed and Embase databases with citation cross-referencing was performed to identify all original clinical articles characterizing MGA flap treatment of upper and lower extremity pathology.
  
  
  RESULTS
  The initial search identified 173 articles which was narrowed down to 40 meeting inclusion criteria, representing a total of 248 cases: 174 and 74 in the upper and lower extremities, respectively. Sixteen distinct recipient sites were identified with union rates ranging from 66 to 100% (98.7% overall). The majority (83.9%) of patients had undergone prior failed surgery. Major complications (those with limb/flap loss or requiring unplanned reoperation) were more frequent for lower versus upper extremity applications (17.1% vs. 6.2%, respectively). Donor site femoral fracture or persistent knee dysfunction occurred in 0.8% and 0.4% of patients, respectively.
  
  
  CONCLUSIONS
  MGA free flaps are a versatile option for upper and lower extremity osseous reconstruction, offering high rates of union with minimal complications for a complex patient population. This study furthers our understanding of patient outcomes following MGA flap reconstruction, which previously was limited to case reports and small case series.
authors.affiliation: Department of Orthopaedics, University of Utah, Salt Lake City, Utah.
authors.forename: Nikolas H
authors.identifier: http://orcid.org/0000-0002-3685-1662
authors.initials: NH
authors.lastname: Kazmers
authors.affiliation: Division of Plastic and Reconstructive Surgery, McGill University, Montreal, Quebec, H3A 14A, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Thibaudeau
authors.affiliation: Department of Orthopaedic Surgery, Penn Medicine University City, Philadelphia, Pennsylvania.
authors.forename: Zvi
authors.initials: Z
authors.lastname: Steinberger
authors.affiliation: Department of Orthopaedic Surgery, Penn Medicine University City, Philadelphia, Pennsylvania.|Division of Plastic Surgery, Perelman Center for Advanced Medicine, Philadelphia, Pennsylvania.
authors.forename: L
authors.initials: L
authors.lastname: Scott Levin
mesh_terms: D058752:Free Tissue Flaps / Q000098:blood supply* / Q000637:transplantation*; D006801:Humans; D007717:Knee / Q000098:blood supply*; D035002:Lower Extremity / Q000601:surgery*; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control; D019651:Plastic Surgery Procedures / Q000379:methods*; D034941:Upper Extremity / Q000601:surgery*