One-Step Cartilage Repair with Bone Marrow Aspirate Concentrated Cells and Collagen Matrix in Full-Thickness Knee Cartilage Lesions: Results at 2-Year Follow-up

Abstract

Objective: The purpose of our study was to determine the effectiveness of cartilage repair utilizing 1-step surgery with bone marrow aspirate concentrate (BMAC) and a collagen I/III matrix (Chondro-Gide, Geistlich, Wolhusen, Switzerland).

Materials and methods: We prospectively followed up for 2 years 15 patients (mean age, 48 years) who were operated for grade IV cartilage lesions of the knee. Six of the patients had multiple chondral lesions; the average size of the lesions was 9.2 cm(2). All patients underwent a mini-arthrotomy and concomitant transplantation with BMAC covered with the collagen matrix. Coexisting pathologies were treated before or during the same surgery. X-rays and MRI were collected preoperatively and at 1 and 2 years' follow-up. Visual analog scale (VAS), International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm, Marx, SF-36 (physical/mental), and Tegner scores were collected preoperatively and at 6, 12, and 24 months' follow-up. Four patients gave their consent for second-look arthroscopy and 3 of them for a concomitant biopsy.

Results: Patients showed significant improvement in all scores at final follow-up (P < 0.005). Patients presenting single lesions and patients with small lesions showed higher improvement. MRI showed coverage of the lesion with hyaline-like tissue in all patients in accordance with clinical results. Hyaline-like histological findings were also reported for all the specimens analyzed. No adverse reactions or postoperative complications were noted.

Conclusion: This study showed that 1-step surgery with BMAC and collagen I/III matrix could be a viable technique in the treatment of grade IV knee chondral lesions.

Keywords: BMAC; Chondro-Gide; Plateltex Act; cartilage; chondral lesion; knee.

Conflict of interest statement

Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the authorship and/or publication of this article.

Figures

Figure 1.

(A) Bone marrow aspirate concentrate (BMAC) clot after activation, (B) grade IV lesion of the patella, (C) covering the lesion with a collagen type I/III matrix after pasting the clot into the lesion, and (D) second-look arthroscopy at 2-year follow-up.

Figure 2.

(A) Boxplots showing the significant improvement in Tegner score from preoperative evaluation to 6, 12, and 24 months (P < 0.005); however, the patients did not reach the preinjury value. (B) Diagram showing the significant improvement in Knee injury and Osteoarthritis Outcome Score (KOOS) subgroups from preoperative to 6, 12, and 24 months (P < 0.005).

Figure 3.

International Knee Documentation Committee (IKDC) objective score showed significant improvement in A and B subgroups from preoperative to 6, 12, and 24 months (P < 0.005).

Figure 4.

Visual analog scale (VAS) and Tegner score showing higher improvement in single versus multiple lesion patients from preoperative evaluation to final follow-up.

Figure 5.

Visual analog scale (VAS) and Knee injury and Osteoarthritis Outcome Score (KOOS) scores showing higher improvement in patients with smaller lesions from preoperative to 6, 12, and 24 months.

Figure 6.

MRI in a 33-year-old amateur soccer player: (A) preoperative T1 sequence in sagittal plane showing a grade IV patellar lesion, (B) T1 sequence in sagittal plane at 2 years’ follow-up showing good coverage of the lesion, preoperative T2 sequence in axial plane showing a grade IV patellar lesion, and T2 sequence in axial plane showing good coverage of the lesion; the associated anterior cruciate ligament reconstruction is evident.

Figure 7.

Biopsy of patient no. 6 obtained after 6 months (original magnification, 40x). (A) Safranin-O staining shows a structure, which is not well organized yet and with many fibrous features. The superficial layer is regular. Proteoglycans and cellular components are not represented. (B) Collagen type I immunostaining shows the positivity of the extracellular matrix in line with the presence of fibrous tissue. (C) The presence of type I collagen does not necessarily imply a negative outcome since positive intracellular staining for type II collagen in this case indicates ongoing remodeling.

Figure 8.

Biopsy of patient no. 3 obtained after 12 months (original magnification, 40x). (A) Safranin-O staining shows a hyaline-like repair tissue. The superficial layer is regular. The subchondral bone shows some signs of ongoing remodeling. Extracellular matrix shows high levels of proteoglycans. Columnar cellular organization of the repair tissue is observed. (B) Immunohistochemical analysis results of collagen type I are completely negative. (C) Collagen type II immunostaining is positive at the extracellular level.

Figure 9.

Biopsy of patient no. 5 after 24 months (original magnification, 40x). (A) Safranin-O staining reveals a well-organized cartilage tissue with the typical features of normal articular cartilage. The superficial layer is regular. The tidemark is well evident. The proteoglycan component is well represented, and the cells show regular distribution along the extracellular matrix. The subchondral bone tissue is in a remodeling process. (B) Immunohistochemical analysis results of collagen type I are almost negative with only a few positive cells at the superficial layer. (C) Type II collagen is slightly positive in the extracellular matrix and at the cellular level.