title: Arthroscopic partial meniscectomy: MR imaging for prediction of outcome in middle-aged and elderly patients.
abstract: OBJECTIVE
  To determine whether preoperative magnetic resonance (MR) imaging could help identify factors associated with poor clinical outcome after arthroscopic partial meniscectomy (APM) in middle-aged and elderly patients with meniscal tears.
  
  
  METHODS
  The prospective, institutional review board-approved, HIPAA-compliant study was performed with informed consent in 53 men and 47 women (average ages, 54.5 and 56.6 years, respectively). Patients underwent knee MR imaging before APM; clinical symptoms were evaluated preoperatively and 1 year postoperatively with International Knee Documentation Committee (IKDC) questionnaire. Overall severity of knee joint degeneration and severity of each feature of joint degeneration were assessed with Boston Leads Osteoarthritis Knee (BLOK) scoring system. Tear length was measured, and type of meniscal tear was classified. Spearman correlation coefficients and relative risks showed the relationship between clinical outcome after APM (difference between preoperative and postoperative IKDC scores) and severity of joint degeneration.
  
  
  RESULTS
  Seventy-four patients with isolated medial APM had a significant (P < .05) inverse correlation between clinical outcome and severity of cartilage loss and bone marrow edema in the medial femoral condyle and medial tibial plateau. Fifteen patients with isolated lateral APM had a significant (P < .05) inverse correlation between clinical outcome and severity of cartilage loss in the lateral femoral condyle and lateral tibial plateau and bone marrow edema in the lateral femoral condyle. One hundred patients with APM had a significant (P < .05) inverse correlation between clinical outcome and severity of meniscal extrusion, total BLOK score, and meniscal tear length. A significantly (P < .05) increased relative risk that a patient would not definitely improve after APM was observed if a meniscal root tear was present.
  
  
  CONCLUSIONS
  Poorer clinical outcome after APM was associated with greater severity of cartilage loss and bone marrow edema in the same compartment as the meniscal tear, greater severity of meniscal extrusion, greater overall severity of joint degeneration, a meniscal root tear, and a longer meniscal tear at preoperative MR imaging.
authors.affiliation: Department of Radiology, Orthopedic Surgery, and Family Medicine, University of Wisconsin Hospital, Clinical Science Center-E3/311, 600 Highland Ave, Madison, WI 53792-3252, USA. r.kijowski@hosp.wisc.edu
authors.forename: Richard
authors.initials: R
authors.lastname: Kijowski
authors.forename: Michael A
authors.initials: MA
authors.lastname: Woods
authors.forename: Timothy A
authors.initials: TA
authors.lastname: McGuine
authors.forename: John J
authors.initials: JJ
authors.lastname: Wilson
authors.forename: Ben K
authors.initials: BK
authors.lastname: Graf
authors.forename: Arthur A
authors.initials: AA
authors.lastname: De Smet
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001182:Arthroscopy / Q000379:methods*; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis* / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D011379:Prognosis; D020127:Recovery of Function; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000070600:Tibial Meniscus Injuries; D016896:Treatment Outcome