Conventional Platelet-Rich Plasma Versus Concentrated Bone Marrow Stem Cell Injections for Osteoarthritis of the Knee

Inclusion Criteria: * Subjects must have bilateral OA and pain in one knee. * Osteoarthritis may be primary or secondary. Knees must have Kellgren-Lawrence Grades 1-3. * Subjects must have previously tried 6 weeks of one of the following conservative treatments: Activity modification, weight loss, physical therapy, anti-inflammatory, or injection therapy. * Patients must be able to provide written informed consent after the nature of the study is fully explained. Exclusion Criteria: * Patients with abnormal hematology, serum chemistry, or screening laboratory results. * Patients taking anti-inflammatory medications (prescription or over-the-counter), including herbal therapies, within 14 days of baseline visit. * Patients taking anti-rheumatic disease medication (including methotrexate or other antimetabolites) within the 3 months prior to study entry. * Patients receiving injections to the treated knee within 3 months prior to study entry. * Patients who are pregnant or currently breast-feeding. * Patients with systemic, rheumatic, or inflammatory disease of the knee or chondrocalcinosis, hemochromatosis, inflammatory arthritis, arthropathy of the knee associated with juxta-articular Paget's disease of the femur or tibia, ochronosis, hemophilic arthropathy, infectious arthritis, Charcot's knee joint, villonodular synovitis, and synovial chondromatosis. * Patients with ongoing known infectious disease. * Patients with clinically significant cardiovascular, renal, hepatic, endocrine disease, or cancer. * Patients participating in a study of an experimental drug or medical device within 30 days of study entry.