Abstract
Orthobiologics (OBs) have seen a constant increase in the number of available therapies and their clinical applications. Existing therapies can be categorized into blood-based (e.g., platelet-rich plasma (PRP)) and tissue/cell-based (e.g. mesenchymal stromal cells) approaches. While the popularity of OBs continues to grow, their diverse natures create unique challenges for the establishment of evidence-based guidelines. PRP has been reported by meta-analyses to increase patient-reported outcomes for conditions such as knee osteoarthritis (KOA), lateral epicondylitis and plantar fasciitis. However, the randomized controlled trials (RCTs) included often exhibit a high risk of bias due to the heterogeneity in the PRP preparation protocols and accompanying measures as well as inconsistent trial quality. The development pipeline of cell/tissue-based therapies is typically longer and more cost-intensive than that of blood-based therapies. Nevertheless, several products have demonstrated clinical safety. While some RCTs and meta-analyses on the outcome of cell/tissue-based therapies exist, their number is considerably lower than that of blood-based therapies and they focus mainly on KOA, with limited evidence on other orthopedic indications. Orthopedic societies such as ESSKA and AAOS have taken on the challenge of developing guidelines for OBs by combining high-level synthesized evidence with expert consensus. Patient stratification strategies represent a promising key to unlocking the full potential of OBs and are currently being investigated in ongoing studies. Further efforts to establish guidelines for the use of OBs should focus on developing frameworks for clinical trials and their reporting, alongside standardized protocols for the preparation, application and accompanying measures of OB therapies.