Functional articular cartilage repair: here, near, or is the best approach not yet clear?

Abstract

In this Review we describe three approaches for cartilage tissue repair at the rheumatology-orthopaedics interface: disease-modifying osteoarthritis (OA) drug (DMOAD) treatment; cell-based therapies, and intrinsic cartilage repair by joint distraction. DMOADs can slow the progression of joint damage. Cell-based therapies have evolved to do the same, through selection of the most potent cell types (and combinations thereof), as well as identification of permissive boundary conditions for indications. Joint distraction techniques, meanwhile, have now demonstrated the capacity to stimulate actual intrinsic tissue repair. Although this progress is promising, true biological joint reconstruction remains distant on the developmental pathway of 'regenerative medicine'. Prolonged functional repair--that is, cure of diseases such as OA--remains an unmet medical need and scientific challenge, for which comparative and constructive interaction between these physical, chemical and cellular approaches will be required. Careful selections of patients and combinations of approaches will need to be made and tested to demonstrate their cost-effectiveness. Only with such rational and integrated assessment of outcomes will the promising results of these approaches be consolidated in clinical practice.

Large, stratified, and mechanically functional human cartilage grown in vitro by mesenchymal condensation

“…A different source of cells, such as bone-marrow or adipose hMSCs, would be of high clinical interest, as it would avoid tissue harvest from the knee associated with morbidity and risk of arthritis. Thus, far, autologous and allogeneic hMSCs have been used in clinical trials as a source of trophic factors to induce cartilage regeneration (28). However, no current method can generate mechanically functional human cartilage starting from hMSCs.…”

Reinforcement of hydrogels using three-dimensionally printed microfibres

“…When embedded within hydrogels, cells need to form a tissue-specific matrix that is capable of repairing or regenerating the damaged tissue. However, hydrogels often have inadequate mechanical properties, which are either unfavourable to embedded cells or make them too weak for application in the musculoskeletal system [5][6][7] .…”

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

“…There are five clinically available treatment options for osteochondral restoration. These include: 1) osteochondral autograft, 2) osteochondral allograft, 3) impaction bone grafting, 4) Autologous chondrocyte implantation (ACI) "Sandwich Technique", and 5) biphasic scaf folds [16][17][18][19][20][21][22][23][24][25][26] . These techniques, along with their strengths and limitations, are summarized in Table 1.…”