By John Urse, DO

After a new (acute) meniscal injury, untreated patients will have a 5 1/2 times greater risk of developing knee osteoarthritis. Successful meniscal repair has demonstrated improved long-term outcomes. (1,2) Potential benefits of Platelet-rich Plasma (PRP) and stem cells relate to :

Anti-inflammatory effects within the joint, which can aid healing response and articular cartilage. Direct stimulation of joint-lining cells. In chronic, long-standing knee osteoarthritis, when comparing patients undergoing knee replacement surgery (Total Joint Replacement) with normal, age-matched controls, it has been found that they have significant deficiency of stem cells in the bone marrow. (3)

Thus, adding PRP to a new meniscal knee injury, or stem cells to an osteoarthritic knee to replenish these cell reservoirs can potentially restore joint health. One study using fluorescently-labeled stem cells to a knee showed dramatic cartilage repair and meniscal regeneration. Interestingly, the injected stem cells induced the body’s own cells to repair the injured area, rather than by acting as building blocks for new tissue(4).


  1. Englund, Meniscal tear in knees without surgery and the development of radiographic osteoarthritis among middle-aged and elderly persons: The Multicenter Osteoarthritis Study. Arthritis Rheum 2009; 60(3): 831-839
  2. Stein, et al: Long-term outcome after arthroscopic meniscal repair versus arthroscopic partial menisectomy for traumatic meniscal tears. Am J Sports Med 2010; 38 (8): 1542-1548
  3. Murphy, et al: Reduced chondrogenic and adipogenic activity of mesenchymal stem cells from patients with advanced osteoarthritis. Arthritis Rheum 2002;46(3): 704-713
  4. Murphy, et al: Stem cell therapy in a caprine model of osteoarthritis. Arhtritis Rheum 2003; 48 (12): 3464-3474