Intra-Articular Injections of Autologous Conditioned Serum to Treat Pain from Meniscal Lesions

Meniscal lesions, depending on their severity and location, sometimes heal spontaneously or may remain asymptomatic. Osteoarthritis (OA) is frequently associated with both symptomatic and asymptomatic meniscal defects [16]. Treatment of meniscal tears by surgical interventions, including resection, refixation/suturing, scaffold implants and allografts, is the clinical standard; however, there is growing concern that arthroscopic meniscus and/or OA surgical treatment may not be indicated in a substantial subset of patients [27–29, 36, 40]. The recent Osteoarthritis Research Society International (OARSI) guidelines recommend more critical application of surgery [34]. The combination of surgery with augmentation procedures has been proposed to improve clinical outcomes, however, only few controlled clinical studies with biological augmentation techniques for the purpose of improving clinical signs of meniscal injuries have been performed [42]. Such augmentation procedures (experimental and clinical) include recombinant growth factors, platelet concentrates (e. g., platelet-rich plasma), stem cell injections and scaffolds. Intra-articular injections of autologous conditioned serum (ACS; Orthokine®) are a therapy for symptomatic osteoarthritic knees and has been in use for > 10 years [43]. ACS contains autologous components derived solely from the patient’s blood and, because ACS is cell-free, it differs fundamentally from platelets or platelet lysate preparations, which contain cells or cell fragments. Elevated concentrations of cytokines and growth factors have been reported with ACS treatment [43, 44]. Intra-Articular Injections of Autologous Conditioned Serum to Treat Pain from Meniscal Lesions