Main and Minor Types of Collagens in the Articular Cartilage: The Role of Collagens in Repair Tissue Evaluation in Chondral Defects

Several collagen subtypes have been identified in hyaline articular cartilage. The main and most abundant collagens are type II, IX and XI collagens. The minor and less abundant collagens are type III, IV, V, VI, X, XII, XIV, XVI, XXII, and XXVII collagens. All these collagens have been found to play a key role in healthy cartilage, regardless of whether they are more or less abundant. Additionally, an exhaustive evaluation of collagen fibrils in a repaired cartilage tissue after a chondral lesion is necessary to determine the quality of the repaired tissue and even whether or not this repaired tissue is considered hyaline cartilage. Therefore, this review aims to describe in depth all the collagen types found in the normal articular cartilage structure, and based on this, establish the parameters that allow one to consider a repaired cartilage tissue as a hyaline cartilage.

EFFICACY OF HERBAL AND NATURALLY-DERIVED DIETARY SUPPLEMENTS FOR THE MANAGEMENT OF KNEE OSTEOARTHRITIS: A MINI-REVIEW

Knee osteoarthritis (OA) accounts for approximately 85% of the burden of OA worldwide. Knee OA is a whole joint disorder involving structural alterations in the hyaline articular cartilage, subchondral bone, ligaments, capsule, synovium, and periarticular muscles. The complex knee OA pathogenesis includes mechanical, inflammatory, and metabolic factors, eventually leading to the synovial joint’s structural destruction and failure. This review aims to present an overview of current knowledge on dietary supplements, such as glucosamine, chondroitin, methylsulfonylmethane, diacerein, avocado-soybean unsaponifiables, curcuminoids, as well as boswellic acids. Results originating from several small studies with natural products in managing knee OA are encouraging. However, additional well-designed placebo-controlled clinical trials are required.

Synergistic interaction of hTGF-β3 with hBMP-6 promotes articular cartilage formation in chitosan scaffolds with hADSCs: implications for regenerative medicine

Background Human TGF-β3 has been used in many studies to induce genes coding for typical cartilage matrix components and accelerate chondrogenic differentiation, making it the standard constituent in most cultivation media used for the assessment of chondrogenesis associated with various stem cell types on carrier matrices. However, in vivo data suggests that TGF-β3 and its other isoforms also induce endochondral and intramembranous osteogenesis in non-primate species to other mammals. Based on previously demonstrated improved articular cartilage induction by a using hTGF-β3 and hBMP-6 together on hADSC cultures and the interaction of TGF- β with matrix in vivo, the present study investigates the interaction of a chitosan scaffold as polyanionic polysaccharide with both growth factors. The study analyzes the difference between chondrogenic differentiation that leads to stable hyaline cartilage and the endochondral ossification route that ends in hypertrophy by extending the usual panel of investigated gene expression and stringent employment of quantitative PCR. Results By assessing the viability, proliferation, matrix formation and gene expression patterns it is shown that hTGF-β3 + hBMP-6 promotes improved hyaline articular cartilage formation in a chitosan scaffold in which ACAN with Col2A1 and not Col1A1 nor Col10A1 where highly expressed both at a transcriptional and translational level. Inversely, hTGF-β3 alone tended towards endochondral bone formation showing according protein and gene expression patterns. Conclusion These findings demonstrate that clinical therapies should consider using hTGF-β3 + hBMP-6 in articular cartilage regeneration therapies as the synergistic interaction of these morphogens seems to ensure and maintain proper hyaline articular cartilage matrix formation counteracting degeneration to fibrous tissue or ossification. These effects are produced by interaction of the growth factors with the polysaccharide matrix.

Particulated Autograft Cartilage Implantation for the Treatment of Osteochondral Lesions of the Talus: A Novel Technique

Osteochondral lesions of the talus often occur following ankle sprains and fractures. Operative intervention is typically required because of the diminished intrinsic repair capability of talar articular cartilage. Several techniques have evolved that emphasize replacing the defect with cartilage that closely mimics the biological properties of hyaline articular cartilage. The goals of operative treatment are resolution of symptoms, physiologic healing, and restoration of function while eliminating the need for further intervention. This article describes a novel, single-step technique for the treatment of osteochondral lesions of the talus with the use of particulated autograft cartilage implantation. Levels of Evidence: Level V

Knee injuries

The knee is a synovial hinge joint which achieves a range of movement of 0°–150° flexion with a complex combination of sliding, gliding, and rolling movements. The three components involved are the medial and lateral compartments of the tibiofemoral joint and the patellofemoral joint. The joint is lined with hyaline articular cartilage and stability is primarily provided by the joint capsule, menisci, ligaments, and muscles....

Distribution of Nanomechanical Properties and Mineralization of the Osteochondral Interface in the Femoral Head

Stiff vertebral bone and compliant hyaline articular cartilage (HAC) anchor together through a thin (∼100’s of microns) region of articular calcified cartilage (ACC). This bone–cartilage, or osteochondral (OC), interface may play a role in osteoarthritis pathogenesis through increased mineralization, disrupting loading, and damaging neighboring tissues [1,2]. Load transmission through OC regions is poorly understood, thus limiting understanding of disease progression and ability to engineer OC interface-like tissues [3].