Acellular Cartilage Repair Technique Based on Ultrapurified Alginate Gel Implantation for Advanced Capitellar Osteochondritis Dissecans

Abstract

Background: One of the most important limitations of osteochondral autograft transplant is the adverse effect on donor sites in the knee. Ultrapurified alginate (UPAL) gel is a novel biomaterial that enhances hyaline-like cartilage repair for articular defects. To avoid the need for knee cartilage autografting when treating osteochondritis dissecans (OCD) of the capitellum, we developed a surgical procedure involving a bone marrow stimulation technique (BMST) augmented by implantation of UPAL gel. Hypothesis: BMST augmented by UPAL gel implantation improves the cartilage repair capacity and provides satisfactory clinical outcomes in OCD of the capitellum. Study Design: Case series; Level of evidence, 4. Methods: A total of 5 athletes with advanced capitellar OCD in the dominant elbow underwent BMST augmented by implantation of UPAL gel. The osteochondral defects were filled with UPAL gel after BMST. At a mean follow-up of 97 weeks, all patients were evaluated clinically and radiographically. Results: At final follow-up, all 5 patients had returned to competitive-level sports, and 4 patients were free from elbow pain. The mean Timmerman-Andrews score significantly improved from 100 to 194 points. Radiographically, all patients exhibited graft incorporation and a normal contour of the subchondral cortex. Magnetic resonance imaging showed that the preoperative heterogeneity of the lesion had disappeared, and the signal intensity had returned to normal. Arthroscopic examinations consistently exhibited improvement in the International Cartilage Regeneration and Joint Preservation Society (ICRS) grade of lesions from 3 or 4 to 1 or 2 in 4 patients at 85 weeks postoperatively. Histologic analysis of biopsy specimens revealed an average total ICRS Visual Assessment Scale II histologic score of 1060. Conclusion: The acellular cartilage repair technique using UPAL gel for advanced capitellar OCD provided satisfactory clinical and radiographic results. The present results suggest that this novel technique is a useful, minimally invasive approach for treating cartilaginous lesions in athletes.

Neo‐cartilage formation using human nondegenerate versus osteoarthritic chondrocyte‐derived cartilage organoids in a viscoelastic hydrogel

“…22,53 Alginate was successfully used in the clinic for the transplantation of human articular chondrocytes to treat cartilage defects in knee joints and for acellular cartilage repair in elbow joints. [54][55][56] Implanting chondrocytes already embedded in a cartilaginous matrix can speed up the regenerative process and improve early load-bearing properties of the newly implanted cells. 10,12,13 Crispim et al hypothesized that chondrocytes in the organoids can only rearrange the alginate network if it behaves like a viscoelastic material.…”

“…Alginate is a biomaterial that can aid in the 3D culture of chondrocytes, as it supports maintenance of the chondrogenic phenotype and chondrocytes embedded in alginate synthesize matrix components that closely resemble those in native articular cartilage 22,53 . Alginate was successfully used in the clinic for the transplantation of human articular chondrocytes to treat cartilage defects in knee joints and for acellular cartilage repair in elbow joints 54–56 . Implanting chondrocytes already embedded in a cartilaginous matrix can speed up the regenerative process and improve early load‐bearing properties of the newly implanted cells 10,12,13 .…”

Application of Alginate Hydrogels for Next-Generation Articular Cartilage Regeneration

“…In the case of an acellular implantation, in situ gelation is preferred at the time of the operation without additional fixation of the augmentation site [163].…”

“…In addition, while alginate may have different endotoxin contents depending on its level of purity, its relative stability with regard to biocompatibility has been demonstrated, supporting its adapted use as a biomaterial [103,163].…”

Autologous Minced Cartilage Implantation for Arthroscopic One-Stage Treatment of Osteochondritis Dissecans of the Elbow

“…Advanced osteochondritis dissecans (OCD) of the humeral capitellum represents a painful and functionally debilitating condition of the elbow joint in young and active patients. Arthroscopic and open therapeutic options include debridement with or without microfracturing/drilling, 1 autologous matrix-induced chondrogenesis, 2 , 3 autologous osteochondral transfer/mosaicplasty, 4 , 5 allogeneic cartilage transplantation, 6 , 7 and autologous chondrocyte implantation (ACI). 8 , 9 …”