Correlating the OA Knee Microenvironment to Outcomes After Regenexx-SD Treatment: A Multi-Site Study

Initial study procedures include baseline evaluation of medical history, knee history, knee examination, medication use, MRI, and subject-reported outcomes. Each osteoarthritic subject will undergo withdrawal of knee joint synovial fluid for each knee being treated (0.3-0.5 ml) which will be analyzed by the research laboratory via multiplexed enzyme linked immunosorbent assay (ELISA) and dimethylmethylene blue assay (DMMB) at pre-injection (2-8 days before Regenexx-SD treatment). Documentation of osteoarthritic joint characteristics and injection procedure details will be recorded throughout the study. The unaffected knee joint will undergo no treatment, but bilateral knees may be treated. The objective of this study is to correlate the pre- Regenexx-SD treatment levels of pro-inflammatory cytokines, anti-inflammatory cytokines, matrix metalloproteinases, and catabolic articular cartilage breakdown products in the osteoarthritic knee synovial fluid microenvironment with 6 month post-treatment clinical outcomes. This data will be used to establish a predictive a priori testing "model" to determine if a patient is a good candidate for the Regenexx-SD treatment based on their initial osteoarthritic knee synovial fluid microenvironment phenotype. It may also be used to determine if the micro-environment can be altered to improve outcome before receiving Regenexx-SD. Incidence of post-operative complications, adverse events, re-injections, and surgical intervention and change in pain score will be considered while determining these direct and indirect associations upon completion of the Regenexx-SD treatment. Components of the synovial fluid will be correlated to post-treatment clinical outcomes, which include several self-reported questionnaires as well as assessment of post-injection complications, adverse events, re-injections and surgical interventions. Patient reported questionnaires include IKDC Subjective Knee Evaluation, Lower Extremity Function Scale, Pain Scales and a Modified Single Assessment Numeric Evaluation (SANE).