Effect of fibrin glue coating on the formation of new cartilage

Arthroscopic microfracture with atelocollagen augmentation for osteochondral lesion of the talus: a multicenter randomized controlled trial

BACKGROUND

We aimed to evaluate whether arthroscopic microfracture with atelocollagen augmentation could improve the clinical outcomes and quality of regenerated cartilage in patients with osteochondral lesion of the talus (OLT). We hypothesized that the clinical outcomes and quality of the regenerated cartilage would be superior in patients undergoing arthroscopic microfracture with atelocollagen augmentation compared to those undergoing arthroscopic microfracture alone.

METHODS

In this multicenter, randomized controlled trial, 60 patients were randomly allocated to two groups: arthroscopic microfracture with atelocollagen augmentation (group 1, n = 31) and arthroscopic microfracture alone (group 2, n = 29). Mean 100-mm visual analog scale (VAS), Hannover scoring system (HSS), and American Orthopedic Foot and Ankle Society (AOFAS) scores were assessed 2 years postoperatively and compared between the groups. The quality of the regenerated cartilage was assessed according to the Magnetic Resonance Observation of CArtilage Repair Tissue (MOCART) score based on magnetic resonance imaging.

RESULTS

Forty-six patients (22 in group 1, 23 in group 2) completed the 2-year follow-up. The quality of the regenerated cartilage assessed based on the MOCART score was significantly superior in group 1 compared to group 2 (64.49 ± 18.27 vs 53.01 ± 12.14, p = 0.018). Clinical outcomes in terms of 100-mm VAS (17.25 ± 20.31 vs 19.37 ± 18.58, p = 0.72), HSS (93.09 ± 13.64 vs 86.09 ± 13.36, p = 0.14), and AOFAS (91.23 ± 8.62 vs 86.91 ± 10.68, p = 0.09) scores were superior in group 1 compared to group 2, but the differences were not statistically significant. Both groups showed significant improvements in clinical outcomes compared with the preoperative values.

CONCLUSION

The quality of the regenerated cartilage was superior after arthroscopic microfracture with atelocollagen augmentation compared to that after microfracture alone in patients with OLT. Clinical outcomes assessed 2 years postoperatively were superior in patients who underwent arthroscopic microfracture with atelocollagen augmentation compared to those who underwent arthroscopic microfracture alone, although the differences were not statistically significant. A long-term study of the cohort is required to confirm these findings.

TRIAL REGISTRATION

ClinicalTrials.gov ( NCT02519881 ), August 11, 2015.

In vivo animal study and clinical outcomes of autologous atelocollagen-induced chondrogenesis for osteochondral lesion treatment

Background

Collagen acts as a scaffold for healing damaged cartilage. This study evaluated the results of an in vivo animal study and provides short-term clinical results on a mixture of atelocollagen and fibrin glue-enhanced microfracture techniques in patients with osteochondral lesions (OCL) of the talus.

Methods

This paper contains animal in vivo data and clinical outcomes on the effectiveness of atelocollagen. An in vivo animal study was conducted with full-thickness cartilage defects created in the femoral condyle of 12 rabbits equally divided into 4 groups evaluated at 2, 4, 8, and 12 weeks. Four chondral lesions were created according to one procedure on each rabbit with each lesion treated as follows: (1) microfracture, (2) microfracture and the lesion covered with atelocollagen, (3) microfracture and the lesion covered with mixture of atelocollagen and fibrin glue, and (4) microfracture and the lesion covered with fibrin glue. In the clinical evaluation, 17 patients were treated with a combination of microfracture and atelocollagen injection for symptomatic full-thickness OCL of the talus. They were evaluated by the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Score (AOFAS), Hannover Ankle Score System (HSS), visual analog scale (VAS), and magnetic resonance imaging (MRI) at baseline and at 12-months follow-up. Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score of the post-op status was compared with the MOCART score and a modified Anderson’s score of the pre-op status.

Results

In the animal study, subchondral bone and cartilage were generated completely in groups 2 and 3 microscopically. Hyaline-like cartilage was found in the repair tissue. In the clinical evaluation, mean AOFAS improved from 62 to 88, mean HSS improved from 62 to 87, and mean VAS score improved from 64 to 18, respectively (p <0.001). Fifteen patients (89 %) reported good or excellent satisfaction. We defined the improvement of most of the subchondral bone edema and bone cyst as well as a chondral lesion by radiologic evaluation.

Conclusions

Rapid regeneration of cartilage was demonstrated in the in vivo animal study, and patients showed significant clinical improvement. Atelocollagen-enhanced microfracture enabled a reasonable treatment of cartilage defects.

Prevention of growth arrest by fibrin interposition into physeal injury

This study investigated the repair effects of fat and fibrin graft interposition through a proximal tibia transphyseal injury model and assessed the effectiveness of treatment to physeal injury with the fibrin. In this study, a unilateral growth plate injury was created in the right proximal tibia of 28 rats without any graft interposition; all left tibias were left untouched. In the other group of 28 rats, a bilateral physeal injury was made with the left tibia filled with autogenously adipose tissue and the right tibia filled with fibrin. To compare the malformed extents induced by different interventions, the length and the metaphyseal-diaphyseal angle of the tibia of three injured groups were examined. Further studies on bone density analysis and histological change were used to compare the bony bridge formation under different interventions. Results showed that the deformity angle and medial length of the tibia were significantly different between the grafted groups and nongrafted group at 4, 16, and 24 weeks postoperative (P<0.01). Results also showed no significant difference between fibrin-graft and fat-graft groups (P>0.05). Furthermore, the bone mineralization density of bony bridge induced by injury was significantly different between the grafted group and nongrafted group at 4, 16, and 24 weeks postoperative (P<0.01). Histological findings showed that bony repair after physeal injury was inhibited by both fibrin and fat interventions. We concluded that fibrin could be a substitute of adipose tissue in preventing the deformities induced by epiphyseal injury. Similar to autogenous fat, fibrin was found to alleviate limb shortness and prevent angular malformation by forming a scar instead of a bony bridge. The use of fibrin can help us to develop effective and compound intervention grafts to prevent skeletal deformity and regenerate normal cartilage tissue in the future.

Autologous chondrocyte implantation with collagen bioscaffold for the treatment of osteochondral defects in rabbits

Osteochondral injury is therapeutically irreversible within current treatment parameters. Autologous chondrocyte implantation (ACI) promises to regenerate hyaline articular cartilage, but conventional ACI is plagued by complications determined by periosteal grafting. Here we propose the utilization of collagen membrane in ACI as an effective bioscaffold for the regeneration of osteochondral lesions. Using a rabbit model of osteochondral injury, we have inoculated autologous chondrocytes onto a type I/III collagen scaffold [so-called matrix-induced ACI (MACI)] and implanted into 3-mm osteochondral knee defects. All untreated defect histology showed inferior fibrocartilage and/or fibrous tissue repair. In our time-course study, ACI with type I/III collagen membrane regenerated cartilage with healthy osteochondral architecture in osteochondral defects at 6 weeks. At 12 weeks, articular cartilage regeneration was maintained, with reduced thickness and proteoglycan compared with the adjacent cartilage. Both 6-week (p < 0.01) and 12-week (p < 0.05) ACI with collagen membrane showed significant improvement as compared with untreated controls. To further examine the efficacy of cartilage regeneration by ACI, we conducted a dose-response study, using chondrocytes at various cell densities between 10(4) and 10(6) cells/cm(2). The results showed that cell density had no effect on outcome histology, but all cell densities were significantly better than untreated controls (p < 0.01) and cell-free collagen membrane treatment (p < 0.05). In short, our data suggest that autologous chondrocyte-seeded type I/III collagen membrane is an effective method for the treatment of focal osteochondral knee injury in rabbits.