title: Increased failure rate of autologous chondrocyte implantation after previous treatment with marrow stimulation techniques.
abstract: BACKGROUND
  Marrow stimulation techniques such as drilling or microfracture are first-line treatment options for symptomatic cartilage defects. Common knowledge holds that these treatments do not compromise subsequent cartilage repair procedures with autologous chondrocyte implantation.
  
  
  OBJECTIVE
  Cartilage defects pretreated with marrow stimulation techniques will have an increased failure rate.
  
  
  METHODS
  Cohort study; Level of evidence, 2.
  
  
  METHODS
  The first 321 consecutive patients treated at one institution with autologous chondrocyte implantation for full-thickness cartilage defects that reached more than 2 years of follow-up were evaluated by prospectively collected data. Patients were grouped based on whether they had undergone prior treatment with a marrow stimulation technique. Outcomes were classified as complete failure if more than 25% of a grafted defect area had to be removed in later procedures because of persistent symptoms.
  
  
  RESULTS
  There were 522 defects in 321 patients (325 joints) treated with autologous chondrocyte implantation. On average, there were 1.7 lesions per patient. Of these joints, 111 had previously undergone surgery that penetrated the subchondral bone; 214 joints had no prior treatment that affected the subchondral bone and served as controls. Within the marrow stimulation group, there were 29 (26%) failures, compared with 17 (8%) failures in the control group.
  
  
  CONCLUSIONS
  Defects that had prior treatment affecting the subchondral bone failed at a rate 3 times that of nontreated defects. The failure rates for drilling (28%), abrasion arthroplasty (27%), and microfracture (20%) were not significantly different, possibly because of the lower number of microfracture patients in this cohort (25 of 110 marrow-stimulation procedures). The data demonstrate that marrow stimulation techniques have a strong negative effect on subsequent cartilage repair with autologous chondrocyte implantation and therefore should be used judiciously in larger cartilage defects that could require future treatment with autologous chondrocyte implantation.
authors.affiliation: Cartilage Repair Center, Brigham & Women's Hospital, Harvard Medical School, 850 Boylston Street, Chestnut Hill, MA 02467, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Minas
authors.forename: Andreas H
authors.initials: AH
authors.lastname: Gomoll
authors.forename: Ralf
authors.initials: R
authors.lastname: Rosenberger
authors.forename: Ronald O
authors.initials: RO
authors.lastname: Royce
authors.forename: Tim
authors.initials: T
authors.lastname: Bryant
mesh_terms: D000293:Adolescent; D000328:Adult; D054544:Arthroplasty, Subchondral; D001182:Arthroscopy; D002358:Cartilage, Articular / Q000293:injuries* / Q000601:surgery; D019902:Chondrocytes / Q000637:transplantation*; D003646:Debridement / Q000379:methods; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology / Q000601:surgery*; D007719:Knee Joint / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012038:Regeneration; D012189:Retrospective Studies; D014182:Transplantation, Autologous; D017211:Treatment Failure; D055815:Young Adult