Researchers are using peoples own stem cells from bone marrow to mend injured muscles and even people who have had heart disease/attacks. They harvest the patient’s own stem cells during the surgery, concentrate them, and then deliver them into the repair. These adult stem cells, harvested from bone marrow within the patient, has the potential to turn into bone, tendon, or cartilage. For the heart, the stem cells release proteins and growth factors, stimulating new heart muscle cells in the damaged area.

http://today.uconn.edu/blog/2015/03/giving-shoulders-new-life/