In the treatment of osteoarthritis and soft tissue injury, early basic science and clinical data have been promising for the use of autologous blood formulations. This review article explores autologous conditioned serum, alpha-2-macroglobulin, and autologous protein solution, which function via overlapping but distinct mechanisms to reduce inflammation, counteract catabolism, and improve joint homeostasis. The ideal timing and quantity of dosing are largely unknown and may vary based on indication. Additional high-quality clinical trials are necessary to define the efficacy of these interventions on both long-term symptomatic improvement and mitigation of osteoarthritic disease progression.
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