title: Open versus arthroscopic meniscus allograft transplantation: magnetic resonance imaging study of meniscal radial displacement.
abstract: OBJECTIVE
  In this imaging study, the radial displacement of meniscal allograft transplants (MATs), inserted with 2 different techniques, namely open soft-tissue fixation and arthroscopic bone tunnel fixation, was compared 1 year postoperatively.
  
  
  METHODS
  In this study, 37 patients received MATs: 16 MATs (10 lateral and 6 medial) were inserted by an open soft-tissue technique (open MATs), whereas 21 MATs (14 lateral and 7 medial) were implanted by an arthroscopic bone tunnel procedure (arthroscopic MATs). Radial displacement, in millimeters, was evaluated 1 year postoperatively on 1.5-T magnetic resonance images. The number of MATs with radial displacement larger or smaller than 3 mm was determined. To compare radial displacement of open versus arthroscopic MATs, the Mann-Whitney U test was used.
  
  
  RESULTS
  The radial displacement of open lateral and medial MATs was significantly larger (all reported P < .02) than that of arthros-copic MATs. In all cases, both open and arthroscopic, the radial displacement of MATs was significantly larger (all reported P < .007) than that of normal menisci. Radial displacement of less than 3 mm was found in 0 of 6 patients with open medial MATs versus 6 of 7 patients with arthroscopic MATs and was found in 1 of 10 patients with open lateral MATs versus 4 of 14 patients with arthroscopic MATs.
  
  
  CONCLUSIONS
  The radial displacement of MATs arthroscopically inserted with bone tunnel fixation is significantly less than the radial displacement of MATs inserted with open soft-tissue fixation. In addition, normal menisci displace significantly less than meniscal allografts. The clinical importance of radial displacement remains to be determined.
  
  
  METHODS
  Level III, retrospective comparative study.
authors.affiliation: Department of Radiology, Ghent University Hospital, Ghent, Belgium. tineke.deconinck@ugent.be
authors.forename: Tineke
authors.initials: T
authors.lastname: De Coninck
authors.forename: Wouter
authors.initials: W
authors.lastname: Huysse
authors.forename: René
authors.initials: R
authors.lastname: Verdonk
authors.forename: Koenraad
authors.initials: K
authors.lastname: Verstraete
authors.forename: Peter
authors.initials: P
authors.lastname: Verdonk
mesh_terms: D000328:Adult; D001182:Arthroscopy; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis* / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000637:transplantation*; D012189:Retrospective Studies; D000070600:Tibial Meniscus Injuries; D014184:Transplantation, Homologous