Clinical results of multilayered biomaterials for osteochondral regeneration

Abstract

Several techniques have been used during the years to treat chondral and osteochondral lesions. Among them, the emerging trend in the field of osteochondral regeneration is to treat the entire osteochondral unit by implanting cell-free scaffolds, which provide a three-dimensional support for the cell growth and may act themselves as stimuli for an “in situ” tissue regeneration. Various multi-layered products have been proposed that mimic both the subchondral bone and the cartilaginous layer. Among these, three have currently been reported in the literature. One has been widely investigated: it is a nanocomposite three-layered collagen-hydroxyapatite scaffold, which is showing promising results clinically and by MRI even at mid-term follow-up. The second is a PLGA-calcium-sulfate bilayer scaffold: however, the literature findings are still controversial and only short-term outcomes of limited case-series have been published. The most recent one is a solid aragonite-based scaffold, which seems to give promising clinical and MRI outcomes, even if the literature is still lacking more in-depth evaluations.Even though the Literature related to this topic is quickly increasing in number, the clinical evidence it is still limited to some case series, and high-level studies are needed to better demonstrate their real effectiveness.

Poly (lactic acid)-based biomaterials for orthopaedic regenerative engineering

“…Although this procedure can be performed in one visit, this system has shown modest improvements in patient outcomes and further clinical trials are needed to investigate its efficacy for cartilage-bone regeneration [302–305]. …”

Bioprinting of osteochondral tissues: A perspective on current gaps and future trends

“…Cell-seeded, biphasic scaffolds may serve as an integrated solution to reca pitulate the osteochondral interface and underlying bone [37,39] , but despite the success in pre-clinical stu dies, only three biphasic osteochondral scaffolds have extensive clinical application [40] . The use of these biphasic systems has resulted in mixed outcomes with frequent failures to restore subchondral bone and long recovery periods [40][41][42] .…”

Preliminary evaluation of an osteochondral autograft, a prosthetic implant, and a biphasic absorbable implant for osteochondral reconstruction in a sheep model

“…24 Chitosan and HPMC are polysaccharides that can be combined and chemically silanized to provide self-hardening properties in vivo. 17,25 Synthetic absorbable biphasic constructs have been proposed as osteochondral substitutes, 26,27 typically consisting of an upper polymeric surface designed to favor chondrogenesis and a deeper component composed of ceramic or collagen to promote integration into the subchondral bone. Such scaffolds have yielded divergent results in clinical studies of human patients and warrant further investigation.…”