Background
Microfracture is the first-line treatment for cartilage defects; however, the suboptimal quality of the repaired cartilage remains an issue.
Hypothesis/Purpose: In this first-in-human study, we hypothesized that the quality of the repaired cartilage in knee defects treated with particulated costal allocartilage with microfracture would be superior to that treated with microfracture alone and the clinical outcomes of the former would be better than those of the latter at 48 weeks postoperatively.
Methods
Ninety patients with cartilage defects were randomly allocated to the treatment group (n = 44, particulated costal allocartilage with microfracture) or control group (n = 46, microfracture alone). Magnetic resonance imaging outcomes of cartilage repair were evaluated at 48 weeks postoperatively using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Patient-reported clinical outcomes (visual analog scale [VAS] pain score, Knee Injury and Osteoarthritis Outcome Score [KOOS], and International Knee Documentation Committee [IKDC] score) and adverse events were evaluated at 12, 24, and 48 weeks postoperatively.
Results
The total MOCART score at 48 weeks postoperatively, which was the primary outcome measure in this study, was significantly higher in the treatment group than in the control group (P <.001). Among the nine variables of the MOCART score, the following six variables were found to be superior in the treatment group than in the control group: degree of repair and defect filling (P <.001), integration to the border zone (P <.001), surface (P =.006), structure (P =.011), signal intensity of the repair tissue (P <.001), and subchondral lamina (P =.005). There were significant between-group differences in KOOS-pain (P =.014), KOOS-ADL (P =.010), KOOS-sports (P =.029), and KOOS-symptoms (P =.039) at 12 weeks postoperatively and in VAS pain score (P =.012) and KOOS-pain (P =.005) at 24 weeks postoperatively. At 48 weeks postoperatively, patient-reported clinical outcomes were comparable between the groups.
Conclusion
Compared with microfracture alone, particulated costal allocartilage with microfracture resulted in superior quality of cartilage repair for cartilage defects in the knee joint.