Rate of improvement was not different after osteochondral repair with matrix-induced autologous chondrocyte implantation or autologous chondrocyte implantation with a cover made from porcine-derived type I/type III collagen

Question: In patients having repair of osteochondral defects in the knee, how does the matrix-induced autologous chondrocyte implantation (MACI) technique compare with autologous chondrocyte implantation with a cover manufactured from porcine-derived type I/type III collagen (ACI-C)? Design: Randomized (allocation concealed)*, unblinded, controlled trial with 1-year follow-up. Setting: A hospital in Middlesex, England, United Kingdom. Patients: 91 patients who were 15 to 50 years of age (mean age, 33 y; 59% men), had an isolated osteochondral defect > 1 cm(2), and could follow a rehabilitation program. Patients with osteoarthritis and inflammatory joint disease were excluded. All patients completed the study. Intervention: Patients were allocated to ACI-C (n = 44) or MACI (n = 47). The ACI-C technique involved cutting the type I/type III collagen membrane to fit the debrided lesion, attaching the membrane with Vicryl sutures and fibrin glue, and injecting a cultured chondrocyte suspension to fill the defect. The MACI technique involved seeding the porcine type I/type III collagen bilayer with chondrocytes and securing the membrane directly to the defect with fibrin glue. Main outcome measures: Change from baseline on the modified Cincinnati knee score (range, 1 to 100; higher scores = better function), the Stanmore functional rating score (range, 0 to 4; higher score = more severe pain), and a visual analog scale (VAS) pain score. Main results: The mean modified Cincinnati knee score improved in both the MACI and ACI-C groups, with no significant difference between groups in the rate of increase (Table). Both groups improved on the Stanmore functional rating score, decreasing from 2.7 to 2.1 in the MACI group and from 3.0 to 2.2 in the ACI-C group. Both groups also had improvement on the VAS pain score, which decreased from 6.0 to 4.1 in the MACI group and 6.0 to 4.3 in the ACI-C group. Conclusion: In patients having repair of osteochondral defects in the knee, the matrix-induced autologous chondrocyte implantation technique and the autologous chondrocyte implantation with a cover manufactured from porcine-derived type I/type III collagen both conferred clinical improvements at 1 year after surgery.