New biotechnologies for musculoskeletal injuries.

The practice of any sport is inherently associated with the risk of musculoskeletal lesions. We describe regenerative medicine technologies, including cellular therapies, gene therapies and multimolecular preparations of growth factors and cytokines, which are expected to advance the field of orthopaedics and sports medicine. Gene therapy involves the introduction of genetic information in the injured tissue to help that tissue to heal and, possibly, regenerate. Cell therapies used in clinical practice are based on the transplantation of adult human cells, which can be at different stages of differentiation. Currently, the stromal vascular fraction, containing stem cells and other niche components, has been injected in the articular cartilage of the knee or delivered via arthroscopy. Bone marrow concentrate (BMC) has been used to manage focal chondral defects via arthroscopy with promising clinical results. In addition, purified mesenchymal stem cells (MSCs) have been injected or delivered as an adjuvant to arthroscopic microfractures, and patients have shown improved clinical outcomes. Laboratory-expanded MSCs injected in osteoarthritis moderately improved pain and functional outcomes. MSC treatment in the form of stromal vascular fraction (SVF) or BMC or laboratory expanded adhesive cells (bone marrow and adipose derived stem cells, BM-MSCs and ADSCs) has been proven to be safe. Despite their safety, expensive regulatory complexities required to implement cell-based therapies make these treatments unavailable for most patients. At present, although some results are promising, all biological interventions are experimental, and cost/efficacy has not been demonstrated yet. Moreover, short follow-up in most studies questions the durability of treatments.