title: A randomized trial comparing accelerated and traditional approaches to postoperative weightbearing rehabilitation after matrix-induced autologous chondrocyte implantation: findings at 5 years.
abstract: BACKGROUND
  While structured postoperative rehabilitation after matrix-induced autologous chondrocyte implantation (MACI) is considered critical, very little has been made available on how best to progressively increase weightbearing and exercise after surgery.
  
  
  OBJECTIVE
  A significant improvement will exist in clinical and magnetic resonance imaging (MRI)-based scoring measures to 5 years after surgery. Furthermore, there will be no significant differences in outcomes in MACI patients at 5 years when comparing a traditional and an accelerated postoperative weightbearing regimen. Finally, patient demographics, cartilage defect parameters, and injury/surgery history will be associated with graft outcome.
  
  
  METHODS
  Randomized controlled trial; level of evidence, 1.
  
  
  METHODS
  Clinical and radiological outcomes were studied in 70 patients who underwent MACI to the medial or lateral femoral condyle, in conjunction with either an "accelerated" or a "traditional" approach to postoperative weightbearing rehabilitation. Under the accelerated protocol, patients reached full weightbearing at 8 weeks after surgery, compared with 11 weeks for the traditional group. Clinical measures (knee injury and osteoarthritis outcome score [KOOS], short-form health survey [SF-36], visual analog scale [VAS], 6-minute walk test, and knee range of motion) were assessed before surgery and at 3, 6, 12, and 24 months and 5 years after surgery. High-resolution MRI was undertaken at 3, 12, and 24 months and 5 years after surgery and assessed 8 previously defined pertinent parameters of graft repair as well as a combined MRI composite score. The association between clinical and MRI-based outcomes, patient demographics, chondral defect parameters, and injury/surgery history was investigated.
  
  
  RESULTS
  Of the 70 patients recruited, 63 (31 accelerated, 32 traditional) underwent clinical follow-up at 5 years; 58 (29 accelerated, 29 traditional) also underwent radiological assessment. A significant time effect (P < .05) was demonstrated for all clinical and MRI-based scores over the 5-year period. While the VAS demonstrated significantly less frequent pain at 5 years in the accelerated group, there were no other significant differences between the 2 groups. Between 24 months and 5 years, a significant improvement (P < .05) in both groups was observed for the sport and recreation subscale of the KOOS as well as a significant decrease (P < .05) in active knee extension for the traditional group. There were no significant differences (P > .05) in the MRI-based scores between 24 months and 5 years after surgery. Patient age and defect size exhibited significant negative correlations (P < .05) with several MRI-based outcomes at 5 years, while there were no significant correlations (P > .05) between clinical and MRI-based outcomes. At 5 years after surgery, 94% and 95% were satisfied with the ability of MACI to relieve their knee pain and improve their ability to undertake daily activities, respectively.
  
  
  CONCLUSIONS
  The outcomes of this randomized trial demonstrate a safe and effective accelerated rehabilitation protocol as well as a regimen that provides comparable, if not superior, clinical outcomes to patients throughout the postoperative timeline.
authors.affiliation: School of Sport Science, Exercise and Health, M408, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Western Australia, Australia. jay.ebert@uwa.edu.au
authors.forename: Jay R
authors.initials: JR
authors.lastname: Ebert
authors.forename: Michael
authors.initials: M
authors.lastname: Fallon
authors.forename: M H
authors.initials: MH
authors.lastname: Zheng
authors.forename: David J
authors.initials: DJ
authors.lastname: Wood
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Ackland
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000293:injuries* / Q000473:pathology / Q000601:surgery*; D019902:Chondrocytes / Q000637:transplantation*; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000473:pathology / Q000534:rehabilitation* / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011795:Surveys and Questionnaires; D013997:Time Factors; D023822:Tissue Engineering; D014182:Transplantation, Autologous / Q000379:methods; D016474:Weight-Bearing; D055815:Young Adult