title: Degree of preoperative subchondral bone edema is not associated with pain and graft outcomes after matrix-induced autologous chondrocyte implantation.
abstract: BACKGROUND
  Matrix-induced autologous chondrocyte implantation (MACI) is an established technique for the repair of knee chondral defects. While a number of factors may affect the clinical outcome, little is known about the influence of subchondral bone abnormalities at the time of surgery on pain and graft outcomes after MACI.
  
  
  OBJECTIVE
  To investigate the association between subchondral bone marrow edema within 3 months before MACI surgery on preoperative and postoperative reported pain and symptoms as well as postoperative graft outcomes.
  
  
  METHODS
  Cohort study; Level of evidence, 3.
  
  
  METHODS
  This retrospective study was undertaken in 56 patients undergoing MACI with clinical and radiological assessments before surgery and at 3, 12, 24, and 60 months after surgery. Patients were assessed using the Pain and Symptoms subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS). High-resolution magnetic resonance imaging (MRI) was used to evaluate the severity of preoperative subchondral bone marrow edema, while graft infill and an MRI composite graft score were evaluated after surgery via the magnetic resonance observation of cartilage repair tissue (MOCART) scoring system. Linear regression utilizing generalized estimating equations was used to investigate the association between preoperative subchondral bone marrow edema scores and preoperative and postoperative KOOS subscores as well as postoperative MRI-based scores of graft repair.
  
  
  RESULTS
  The degree of preoperative subchondral bone marrow edema was not significantly associated with postoperative outcomes, whereby there was no evidence of a difference between edema subgroups over all time points for the KOOS-Pain subscore (P = .644), KOOS-Symptoms subscore (P = .475), or MRI composite score (P = .685) after adjustment for potential confounders of age, body mass index, defect size, and defect location.
  
  
  CONCLUSIONS
  No association was demonstrated between the severity of preoperative subchondral bone marrow edema with postoperative patient-reported knee pain or symptoms or postoperative graft repair assessed via MRI.
authors.affiliation: School of Sport Science, Exercise and Health, University of Western Australia, Crawley, Perth, Australia jay.ebert@uwa.edu.au.
authors.forename: Jay R
authors.initials: JR
authors.lastname: Ebert
authors.affiliation: The School of Physiotherapy and Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Australia.
authors.forename: Anne
authors.initials: A
authors.lastname: Smith
authors.affiliation: Perth Radiological Clinic, Subiaco, Perth, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Fallon
authors.affiliation: School of Surgery (Orthopaedics), University of Western Australia, Crawley, Perth, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: Wood
authors.affiliation: School of Sport Science, Exercise and Health, University of Western Australia, Crawley, Perth, Australia.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Ackland
mesh_terms: D000293:Adolescent; D000328:Adult; D054544:Arthroplasty, Subchondral / Q000009:adverse effects*; D001855:Bone Marrow Diseases / Q000473:pathology*; D002358:Cartilage, Articular / Q000601:surgery*; D019902:Chondrocytes / Q000637:transplantation*; D004487:Edema / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000209:etiology*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D054457:Tissue Scaffolds; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D055815:Young Adult
keywords: magnetic resonance imaging; matrix-induced autologous chondrocyte implantation; postoperative assessment; subchondral bone marrow edema