title: Does Medial Meniscal Allograft Transplantation With the Bone-Plug Technique Restore the Anatomic Location of the Native Medial Meniscus?
abstract: BACKGROUND
  Previous work has shown the importance of restoring the normal structure of the native meniscus with meniscal allograft transplantation.
  
  
  OBJECTIVE
  The purpose of this study was to compare the anatomic positions of the anterior horn and posterior horn between the preoperative medial meniscus and the postoperative meniscal allograft after medial meniscal allograft transplantation with the bone-plug technique. The hypothesis was that the bone-plug technique could restore the preoperative structure of the native medial meniscus.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  Between December 1999 and December 2013, a total of 59 patients (49 male, 10 female) underwent medial meniscal allograft transplantation by use of the bone-plug technique. The anatomic positions of both horns in the native medial meniscus and in the meniscal allograft were measured via MRI. The percentage reference method was used to measure the locations of both horns.
  
  
  RESULTS
  On coronal MRI, the mean absolute distance of the posterior horn from the lateral border of the tibial plateau changed from 45.2 ± 3.3 to 48.1 ± 4.2 mm (P < .05), and the percentage distance of the posterior horn changed from 59.6% to 63.0% (P < .05). On sagittal MRI, the mean absolute distance of the posterior horn from the anterior reference point changed from 40.3 ± 3.0 to 42.0 ± 3.5 mm (P < .05), and the mean percentage distance of the posterior horn changed from 76.5% to 79.4% (P <.05). On coronal MRI, the mean absolute distance of the anterior horn from the lateral border of the tibial plateau changed from 41.3 ± 4.2 to 48.5 ± 5.6 mm (P < .05), and the mean percentage distance of the anterior horn changed from 54.5% to 63.8% (P < .05). On sagittal MRI, the mean absolute distance of the anterior horn from the anterior reference point changed from 5.5 ± 1.0 to 9.9 ± 2.9 mm (P < .05), and the mean percentage distance of the anterior horn changed from 10.6% to 19.0% (P < .05).
  
  
  CONCLUSIONS
  Despite attempts to place the meniscal allograft in the same position as the native meniscus, the anatomic locations of both horns were shifted posteromedially compared with those of the native medial meniscus. There were significant differences, attributed to several limitations in the bone-plug technique, between the preoperative and postoperative values of both horns. However, the posterior horn showed a location change of <5 mm, on average, in both the coronal and sagittal planes, whereas the anterior horn showed a location change of ≥ 5 mm in the coronal plane but <5 mm in the sagittal plane.
authors.affiliation: Department of Orthopedic Surgery, College of Medicine, Asan Medical Center, University of Ulsan, Seoul, Korea.
authors.forename: Nam-Ki
authors.initials: NK
authors.lastname: Kim
authors.affiliation: Department of Orthopedic Surgery, College of Medicine, Asan Medical Center, University of Ulsan, Seoul, Korea sibin@amc.seoul.kr.
authors.forename: Seong-Il
authors.initials: SI
authors.lastname: Bin
authors.affiliation: Department of Orthopedic Surgery, College of Medicine, Asan Medical Center, University of Ulsan, Seoul, Korea.
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Department of Orthopedic Surgery, College of Medicine, Busan Paik Hospital, Inje University, Busan, Korea.
authors.forename: Chang-Rack
authors.initials: CR
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000473:pathology* / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008592:Menisci, Tibial / Q000033:anatomy & histology* / Q000637:transplantation*; D008875:Middle Aged; D011184:Postoperative Period; D014184:Transplantation, Homologous; D055815:Young Adult
keywords: anterior horn; bone-plug technique; medial meniscus; meniscal allograft transplantation; posterior horn