The objective of this study is to compare the efficacy and safety of MACI® vs arthroscopic microfracture in the treatment of participants aged 10 to 17 years with symptomatic articular chondral or osteochondral defects of the knee.
Symptomatic cartilage or osteochondral defects
One or more International Cartilage Repair Society (ICRS) Grade III or IV chondral or unsalvageable osteochondral defects located on the femoral condyles and/or trochlea amenable to treatment with the surgical procedure determined at randomization (MACI or microfracture).
Concurrent ICRS Grade I and II defects are acceptable on the tibia if they remain untreated (or are treated with debridement only) at the time of study treatment.
Participants with a potentially re-attachable osteochondral fragment, identified by magnetic resonance imaging (MRI) and that has not previously been repaired, may be consented to the study and undergo baseline assessments per protocol and prior to confirmatory arthroscopy (Visit 2). At arthroscopy, an attempt will be made to reattach the osteochondral fragment. If this is successful, the participant will be excluded from the study and deemed an intra-operative screen failure. If the attempted reattachment fails and no other
At least 1 defect size ≥1.5 cm2 on the patella, femoral condyles and/or the trochlea; defects include OCD lesions with a bone lesion depth of ≤6 mm and does not require a bone graft.
Salvageable OCD lesions must have failed prior conservative and a reparative treatment, and the participant still experiences pain associated with the osteochondral lesion. Participants with defects as a result of trauma or unknown etiology are eligible regardless of prior treatments.
Stable target knee (i.e., anterior and posterior cruciate ligaments should be free of laxity as well as stable and intact). Ligament repair or reconstruction procedures are allowed prior to screening arthroscopy.
Intact meniscus or partial meniscus (at least 50% of functional meniscus remaining) in the target knee. Meniscal repair or resection might be performed either staged or concurrent with the cartilage repair procedure provided that the surgeon was able to confirm that at least 50% of functional meniscus would remain after the corrective meniscal treatment.