Mesenchymal stem cells(MSC) can morph into ligament, cartilage, bone or fat. How and why they differentiate is critical. Sen et. al., recently demonstrated that mechanical stress (the laboratory equivalent of exercise) lead mesenchymal stem cells to differentiate into bone instead of fat, even if they are given chemical signals to become fat. What does this mean? MSC can become fat cells simply by lack of exercise. There are other factors which give MSC’s clues to turn into fat vs cartilage, bone or ligament.
If you are a patient with worn knee cartilage and are restricted as a result of pain, one surgical option would be micro-fracture. 
This is a surgical procedure where multiple small punctures are made into the femur(thigh) bone in an effort to stimulate cartilage regeneration. A fragile thin clot is formed at the site which mandates a period on 6-8 weeks of non-weight bearing. No running, golfing, cycling. No fun!
Regenexx offers patients the opportunity to use their own MSC’s to generate cartilage via a needle-in, needle-out procedure. No surgery is required. Most importantly, the physical restriction are minimal. In contrast to micro-fracture technique, the Regenexx patient is encouraged to exercise. The mechanical loading associated with exercise gives the stem cells signals to change into cartilage.
Please review knee MRI of a patient who underwent stem cell therapy at Regenexx with radiographic evidence of increased cartilage as well as complete resolution of her severe knee pain.
