Clinical and magnetic resonance imaging-based outcomes to 5 years after matrix-induced autologous chondrocyte implantation to address articular cartilage defects in the knee.
BACKGROUND
The availability remains limited of midterm clinical and radiologic results into matrix-induced autologous chondrocyte implantation (MACI). Outcomes are required to validate the efficacy of MACI as a suitable surgical treatment option for articular cartilage defects in the knee.


OBJECTIVE
A significant improvement in clinical and magnetic resonance imaging-based (MRI-based) outcomes after MACI will exist throughout the postoperative timeline to 5 years after surgery. Furthermore, patient demographics, cartilage defect parameters, and injury/surgery history will be associated with patient and graft outcome, whereas a significant correlation will exist between clinical and MRI-based outcomes at 5 years after surgery.


METHODS
Case series; Level of evidence, 4.


METHODS
A prospective evaluation was undertaken to assess clinical and MRI-based outcomes to 5 years in 41 patients (53 grafts) after MACI to the knee. After MACI surgery and a 12-week structured rehabilitation program, patients underwent clinical assessments (Knee injury and Osteoarthritis Outcome Score, SF-36, 6-minute walk test, knee range of motion) and MRI assessments at 3, 12, and 24 months, as well as 5 years after surgery. The MRI evaluation assessed 8 previously defined pertinent parameters of graft repair, as well as a combined MRI composite score.


RESULTS
A significant improvement (P < .05) was demonstrated for all Knee injury and Osteoarthritis Outcome Score and SF-36 subscales over the postoperative timeline, as well as the 6-minute walk test and active knee extension. A significant improvement (P < .0001) was observed for the MRI composite score, as well as several individual graft scoring parameters. At 5 years after surgery, 67% of MACI grafts demonstrated complete infill, whereas 89% demonstrated good to excellent filling of the chondral defect. Patient demographics, cartilage defect parameters, and injury/surgery history demonstrated no significant pertinent correlations with clinical or MRI-based outcomes at 5 years, and no significant correlations existed between clinical and MRI-based outcome measures. At 5 years after surgery, 98% of patients were satisfied with the ability of MACI surgery to relieve knee pain; 86%, with improvement in their ability to perform normal daily tasks; and 73%, with their ability to participate in sport 5 years after MACI.


CONCLUSIONS
These results suggest that MACI provides a suitable midterm treatment option for articular cartilage defects in the knee. Long-term follow-up is essential to confirm whether the repair tissue has the durability required to maintain long-term patient quality of life.
School of Sport Science, Exercise and Health, University of Western Australia, Crawley, Perth, Australia. jayebert@cyllene.uwa.edu.au
Jay R
JR
Ebert
William B
WB
Robertson
Jennifer
J
Woodhouse
Michael
M
Fallon
M H
MH
Zheng
Timothy
T
Ackland
David J
DJ
Wood
D000293:Adolescent; D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000293:injuries / Q000473:pathology / Q000601:surgery*; D002648:Child; D019902:Chondrocytes / Q000637:transplantation*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D055815:Young Adult