Abstract
Chondral knee defects have a limited ability to be repaired. Current surgical interventions have been unable to regenerate articular cartilage with the mechanical properties of native hyaline cartilage. The use of a scaffold-based approach is a potential solution. Scaffolds are often implanted with cells to stimulate cartilage regeneration, but cell-based therapies are associated with additional regulatory restrictions, an additional surgical procedure for cell harvest, time for cell expansion, and the associated costs. To overcome these disadvantages, cell-free scaffolds can be used in isolation allowing native cells to attach over time. This review discusses the optimal properties of scaffolds used for chondral defects, and the evidence for the use of hydrogel scaffolds and hydrogel–synthetic polymer hybrid scaffolds. Preclinical and clinical studies have shown that cell-free scaffolds can support articular cartilage regeneration and have the potential to treat chondral defects. However, there are very few studies in this area and, despite the many biomaterials tested in cell-based scaffolds, most cell-free studies focused on a specific type I collagen scaffold. Future studies on cell-free scaffolds should adopt the modifications made to cell-based scaffolds and replicate them in the clinical setting. More studies are also needed to understand the underlying mechanism of cell-free scaffolds.
Highlights
Cartilage is an avascular, aneural and alymphatic tissue, and knee cartilage damage has a limited ability to repair without surgical intervention [1]
Many different synthetic polymers were tested as potential scaffolds, including polyglycolic acid (PGA), polylactic acid (PLA), poly(lactic-co-glycolic) acid (PLGA) and poly(ethylene glycol)-terephthalate/poly(butylene terephthalate) (PEOT/PBT) [42]
A possible explanation is that cell-based scaffolds that utilise the more established autologous chondrocyte implantation (ACI) technique are considered more appropriate as they are focused on refining the current best practice in order to improve clinical outcomes rather than investigating the more radical cell-free scaffolds
Summary
Aneural and alymphatic tissue, and knee cartilage damage has a limited ability to repair without surgical intervention [1]. Despite the many different treatments currently available, none of the procedures have been able to regenerate cartilage that mimics the mechanical properties of native articular hyaline cartilage [16]. As no cells are loaded in the scaffold before application, there is no need for a tissue harvest procedure or cell expansion thereby eliminating the possibility of donor site morbidity and the associated costs. This allows a single-stage treatment to be delivered at a fraction of the cost. This review will focus on the potential of cell-free scaffolds as a monotherapy in the management of chondral knee defects
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have