There is good scientific rationale to support the use of growth factors to promote musculoskeletal tissue regeneration. However, the clinical effectiveness of platelet-rich plasma (PRP) and other blood-derived products has yet to be proven. Characterization and reporting of PRP preparation protocols utilized in clinical trials for the treatment of musculoskeletal disease is highly inconsistent, and the majority of studies do not provide sufficient information to allow the protocols to be reproduced. Furthermore, the reporting of blood-derived products in orthopaedics is limited by the multiple PRP classification systems available, which makes comparison of results between studies challenging. Several attempts have been made to characterize and classify PRP; however, no consensus has been reached, and there is lack of a comprehensive and validated classification. In this annotation, we outline existing systems used to classify preparations of PRP, highlighting their advantages and limitations. There remains a need for standardized universal nomenclature to describe biological therapies, as well as a comprehensive and reproducible classification system for autologous blood-derived products. Cite this article:
The majority of patients with osteoarthritis present to orthopaedic surgeons seeking relief of pain and associated restoration of function. Although our understanding of the physiology of pain has improved greatly over the last 25 years there remain a number of unexplained pain-related observations in patients with osteoarthritis. The understanding of pain in osteoarthritis, its modulation and treatment is central to orthopaedic clinical practice and in this annotation we explore some of the current concepts applicable. We also introduce the concept of the ‘phantom joint’ as a cause for persistent pain after joint replacement.
