Costal Chondrocyte-Derived Pellet-Type Autologous Chondrocyte Implantation versus Microfracture for Repair of Articular Cartilage Defects: A Prospective Randomized Trial

Abstract

Objective: To compare the efficacy and safety of costal chondrocyte-derived pellet-type autologous chondrocyte implantation (CCP-ACI) with microfracture (MFx) for repair of articular cartilage defects of the knee.

Design: Thirty subjects with an International Cartilage Repair Society (ICRS) grade 3 to 4 chondral defect (2-10 cm2 in area; ≤4 cm3 in volume) were randomized at a ratio of 2:1 (CCP-ACI:MFx). Twenty patients were allocated in the CCP-ACI group and 10 patients in the MFx group. CCP-ACI was performed by harvesting costal cartilage at least 4 weeks before surgery. Implantation was performed without any marrow stimulation. Efficacy and safety were assessed at weeks 8, 24, and 48 after surgery according to the magnetic resonance observation of cartilage repair tissue (MOCART) score and clinical outcomes.

Results: MOCART scores improved from baseline to 24 and 48 weeks postoperatively in both treatment groups. The improvement in MOCART scores in the CCP-ACI group was significantly greater than that in the MFx group at 24 and 48 weeks (39.1 vs 21.8 and 43.0 vs 24.8, respectively). The proportions of complete defect repair and complete integration were significantly higher in the CCP-ACI group than the MFx group at 48 weeks. Improvement in Lysholm score and KOOS subscores, including Function (Sports and Recreational Activity) and knee-related quality of life was significantly greater in the CCP-ACI group than the MFx group at 48 weeks (35.4 vs 31.5, 35.7 vs 28.5, and 27.9 vs 11.6, respectively).

Conclusion: Treatment of cartilage defects with CCP-ACI yielded satisfactory cartilage tissue repair outcomes, with good structural integration with native cartilage tissue shown by magnetic resonance imaging at 24 and 48 weeks after surgery.

Level of evidence: Level 1: Randomized controlled study.

Trial registration: ClinicalTrials.gov NCT03545269.

Keywords: autologous chondrocyte implantation; cartilage repair; chondral lesion; costal cartilage.

Conflict of interest statement

Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Authors J.L. and J.Y.L. have stock and stock options in Biosolution Co., Ltd. The other authors (K.H.Y., J.D.Y., C.H.C., S.G.K., and J.Y.P.) have received no benefits in any form from a commercial party related directly or indirectly to the subject of this article.

Figures

Figure 1.

Flowchart of study population recruitment.

Figure 2.

(A) Costal chondrocyte–derived pellet-type autologous chondrocyte implantation (CCP-ACI) via a 5-mL prefilled syringe. (B) Animation showing procedures for CCP-ACI. (C) Image showing CCP-ACI applied to the defect site with fibrin glue applied to fix the pellets.

Figure 3.

(A) Magnetic resonance observation of cartilage repair tissue (MOCART) scores of the costal chondrocyte–derived pellet-type autologous chondrocyte implantation (CCP-ACI) group and microfracture (MFx) group at baseline, 24 weeks, and 48 weeks after surgery.

Figure 4.

(A1) Preoperative magnetic resonance imaging (MRI) scan showing osteochondritis dissecans at lateral femoral condyle. (A2) Postoperative costal chondrocyte–derived pellet-type autologous chondrocyte implantation (CCP-ACI) 48-week MRI scan showing less satisfactory defect repair and integration. (B1) Preoperative MRI scan showing cartilage defect at trochlea. (B2) Postoperative CCP-ACI 48-week MRI scan showing satisfactory defect repair and integration. (C1) Preoperative MRI scan showing cartilage defect at trochlea. (C2) Postoperative CCP-ACI 48-week MRI scan showing very satisfactory defect repair and integration. (D1) Preoperative MRI scan showing cartilage defect at medial femoral condyle. (D2) Postoperative microfracture (MFx) 48-week MRI scan showing poor defect repair and integration. (E1). Preoperative MRI scan showing cartilage defect at trochlea. (E2) Postoperative MFx 48-week MRI scan showing satisfactory defect repair and integration.

Figure 5.

Graph showing clinical outcomes scores.