Multiple clinical trials currently are underway at Regenexx, with the aim of critically examining techniques and sharing regenerative medicine outcomes with the scientific community. One of these trials is aimed at evaluating the success of injections of bone-marrow concentrate (which includes adult mesenchymal cells) directly into supraspinatus tendon rotator cuff tears.
The supraspinatus is one of four muscles that give motion to the shoulder. These four collectively are termed the rotator cuff. Like all muscles, the supraspinatus morphs into a tendon as it attaches to its insertion site on the humerus. This transition point between muscle and bone is termed an enthesis. Your body’s skeleton is a framework of bones resisting the constant downward force of gravity. In order for your body to move, muscles must contract or shorten in length, bringing the bones they bridge closer together.
In order to reduce variables that could cloud the outcome of our clinical study, patients had to be screened to ensure that only the supraspinatus muscle and none of the other muscles in the rotator cuff were damaged.
One such candidate for the study was a 28-year-old Brazilian jiu jitsu practitioner who had torn his supraspinatus muscle while weightlifting one year prior to visiting a Regenexx clinic. After careful review that includes a physical examination, as well as MRI and ultrasound studies, it was determined that he would be a suitable candidate for the study.
Participants in this clinical trial were assigned either to a group to receive bone-marrow injections immediately, or to a control group whose members instead would undergo six months of physical therapy. Data from the control group allows researchers to eliminate the possibility that a successful outcome from the treatment group is not just a function of natural healing that would have taken place over time of its own accord.
Our Brazilian patient was assigned to the treatment group that were undergoing injection of bone-marrow concentrate into their supraspinatus tendons.
The enthesis site, where muscle morphs into bone, is an area rich in osteogenic (bone-generating) stem cells. Through careful agitation with the tip of a needle after appropriate local anesthesia, Regenexx doctors stimulate the local bone stem cells present in the superficial periosteum to transform into enthesis tissue—thereby anchoring the stem cells placed into the tendon and muscle to the bone.
The placement of the stem cells and other progenitor cells directly into the muscle allows the cells to begin to act on local cells within the tissue and begin repair, as well as to begin to differentiate into new target tissue themselves. Mesenchymal stem cells derive from the mesoderm of the early embryo. When life is beginning to develop, all cells are similar. They quickly develop in the early embryo into three cell lines termed the mesoderm, endoderm and ectoderm. Endoderm cells give rise to organs, ectoderm to nerves and skin, and mesoderm to connective tissue (bones, tendons, ligaments, cartilage, muscle, blood vessels—the important components used in interventional orthopedics and regenerative medicine). Adult mesoderm cells can readily only become connective tissue. In 2012, a Japanese and English research pair won the Nobel prize by proving that even adult cells under the right condition could revert back to embryonic cells and thus give rise to all three cell lines.)
Once mesenchymal stem cells are in contact with the area in need of healing, surface proteins specific to the target tissue bind to receptors on the mesenchymal stem cells’ surface, transmitting messages into the nucleus where DNA is housed. These messages tell the DNA which genes should be expressed to generate new cells to replace the damaged tissue.
Once placed, the new cells need direction. One way of stimulating the cells and optimizing their growth is through exercise. The use of proper rehabilitation exercises after regenerative procedures allows the cells to gain mechanical stimulation in the correct fashion, which facilitates proper growth. The use of eccentric exercises (resistance against the muscle as it is lengthening as opposed to contracting or shortening) acts on local stem cells in the muscle to direct differentiation of injured tissue.
The use of such exercises over the course of a few weeks enabled our Brazilian patient to optimize his stem-cell-based procedure. Five months after his treatment, he reported full return of range of motion and strength and was cleared by Regenexx doctors to return to competitive jiu jitsu. A few months later he took third place in a jiu jitsu competition.
“Supraspinatus Tendon Tear Treatment” first appeared as a guest post on the Regenexx blog.