title: Meniscal allograft shrinkage-MRI evaluation.
abstract: OBJECTIVE
  Meniscal allograft transplantation (MAT) has been shown to be an effective treatment option for patients with symptomatic meniscal-deficient knees. Several studies have described shrinkage after transplantation of a meniscal allograft; however, no study has specifically quantified the rate or degree of shrinkage that occurs. The purpose of this study was to determine the frequency and amount of meniscal shrinkage that occurs following transplantation.
  
  
  METHODS
  A prospective study of 25 patients undergoing MAT was performed. Patients underwent MR scans of the meniscal allograft at 1 and 6 months following surgery. Meniscal volume was determined by laser-based noncontacting 3-D coordinate digitizing system (3-DCDS) to acquire the 3-D geometry of the meniscus. The meniscus volume at 1 and 6 months were compared to determine the amount of shrinkage that occurred.
  
  
  RESULTS
  The average amount of meniscal shrinkage was 7% (range 0 to 22%). Seventeen (68%) of the grafts showed at least 5% shrinkage and 8 (32%) showed 10% or greater.
  
  
  CONCLUSIONS
  Meniscal allograft shrinkage is common following transplantation. The average amount of shrinkage is 7%; however, nearly 32% of the grafts had 10% or more shrinkage.
  
  
  METHODS
  2.
authors.affiliation: Department of Orthopaedics, The Orthopaedic Clinic Association, Phoenix, Arizona 85016, USA. tcarter@tocamd.com
authors.forename: Thomas
authors.initials: T
authors.lastname: Carter
authors.forename: Kostas John
authors.initials: KJ
authors.lastname: Economopoulos
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000033:anatomy & histology* / Q000637:transplantation*; D008875:Middle Aged; D011446:Prospective Studies; D014184:Transplantation, Homologous; D055815:Young Adult