title: Articular Cartilage Degenerates After Subtotal/Total Lateral Meniscectomy but Radiographic Arthrosis Progression Is Reduced After Meniscal Transplantation.
abstract: BACKGROUND
  Little is known about the degree of articular cartilage degeneration after subtotal/total lateral meniscectomy in patients who later undergo isolated lateral meniscal allograft transplantation (LMAT). It has not yet been studied whether arthritic changes as shown on radiographs were lower during the posttransplantation period than during the meniscus-deficient period.
  
  
  OBJECTIVE
  Articular cartilage will significantly degenerate during the meniscus-deficient period, but the progression in radiographic arthrosis is reduced after LMAT.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  This study retrospectively reviewed 49 patients who underwent subtotal/total lateral meniscectomy before isolated LMAT performed over 1 year later by the same surgeon. International Cartilage Repair Society (ICRS) grades of the femorotibial joint at the time of subtotal/total meniscectomy and at LMAT were compared. Radiographic evaluation was performed at the time of initial meniscectomy, LMAT, and the latest follow-up in 38 patients (after 11 patients whose radiographs showed incomplete ossification at the time of meniscectomy were excluded). Arthrosis, based on Kellgren-Lawrence (K-L) grades, was determined on standing anteroposterior views. Joint space width (JSW) was measured on weightbearing flexion posteroanterior views.
  
  
  RESULTS
  Over a mean meniscus-deficient period of 4.5 years (range, 1-13 years), articular cartilage significantly degenerated on the femoral and tibial sides (P < .001). Grade ≥3 degeneration on the lateral tibial plateau was observed in 13 patients (27%) at the time of initial meniscectomy; this incidence doubled to 28 patients (57%) by the time of LMAT. The K-L grades worsened (P < .001) and JSWs narrowed significantly (-0.65 ± 1.09 mm; P = .001) during the mean meniscus-deficient period of 3.1 years. At radiographic assessment, however, the K-L grades (P = .097) and JSWs (4.06 ± 1.19 vs 3.92 ± 1.21 mm; mean difference, -0.14 ± 0.68 mm; P = .213) did not significantly change during the mean posttransplantation period of 3.8 years. The changes in ICRS grade and JSW during the meniscus-deficient period were not associated with age, body mass index, mechanical axis deviation, or Tegner activity level (P > .05 for all relationships).
  
  
  CONCLUSIONS
  Patients who underwent isolated LMAT showed substantial articular cartilage degeneration at the time of initial subtotal/total lateral meniscectomy, and this degeneration progressed thereafter. Further progression of radiographic arthrosis was delayed after LMAT.
authors.affiliation: Department of Orthopedic Surgery, College of Medicine, Catholic University, Incheon St Mary's Hospital, Incheon, Korea.
authors.forename: Bum-Sik
authors.initials: BS
authors.lastname: Lee
authors.affiliation: Department of Orthopedic Surgery, College of Medicine, University of Ulsan, Asan Medical Center, 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, University of Ulsan, Asan Medical Center, Seoul, Korea.
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001168:Arthritis / Q000000981:diagnostic imaging* / Q000473:pathology / Q000517:prevention & control; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000473:pathology*; D002648:Child; D018450:Disease Progression; D005260:Female; D006801:Humans; D065466:Lysholm Knee Score; D008297:Male; D008592:Menisci, Tibial / Q000601:surgery* / Q000637:transplantation; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000473:pathology*; D011859:Radiography; D012189:Retrospective Studies; D014184:Transplantation, Homologous; D016474:Weight-Bearing; D055815:Young Adult
keywords: lateral; meniscus allograft transplantation; subtotal; total