Bone marrow mesenchymal stromal cell-derived exosomes in knee osteoarthritis: Bridging mechanistic understanding to clinical applications

Knee osteoarthritis is recognised as a whole-joint disorder involving cartilage, synovium, subchondral bone and nociceptive pathways. Conventional therapies provide symptomatic relief but rarely alter structural progression. Mesenchymal stromal cell (MSC) injections improve pain and function, yet structural benefits remain modest and variable. Increasing evidence indicates that much of the MSC effect is mediated by secreted extracellular vesicles (EVs), particularly those derived from bone marro