Regenerative Medicine and Heel Pain, Part 2 - Dr. Ed Davis, San Antonio Podiatrist, discusses advanced treatments for heel pain.
Plantar fasciitis is an inflammatory condition of the fascia. If plantar fasciitis persists, chronic inflammation can lead to long term degenerative changes of the fascia known as plantar fasciosis. The fascia, in plantar fasciosis can become thick and relatively hardened with loss of normal flexibility. The plantar fascia is a broad band of fascial tissue that spans the foot from the heel to the ball of the foot. It acts both to support the foot and function as a spring to aid in propulsion.
The plantar fascia, like most fascia in the body has little or no blood supply of its own but derives that supply from surrounding muscle tissue. As the fascia thickens due to chronic inflammation, it becomes more difficult for blood to perfuse it so the center of the fascia, the area furthest away from the blood vessels becomes diseased.
Not all longstanding or seemingly difficult cases of heel pain are due to plantar fasciosis. The best way to determine if fasciosis is present is via imaging, specifically diagnostic ultrasound (sonography) which is the gold standard for analysis of such tissue due to its ability to show fine details.
The goal of treatment of fasciosis involves the induction or stimulation of the process of tissue repair, that is, getting the body to remove the diseased tissue and replace it with normal tissue. That is the basis of regenerative medicine.
The first form of regenerative medicine for fasciosis was ESWT or extracorporeal shockwave therapy. ESWT involves the application of sonic shockwaves, similar to the technology used to break down kidney stones, to induce regeneration of the fascia. ESWT induces neovascularization, the production of new blood vessels and effectively thins the fascia making it more flexible, more functional and less painful. The process takes approximately 12 weeks but patients generally experience relief starting about the sixth week after treatment.
Tissue regeneration can also be encouraged by the introduction of growth factors into the fascia. Growth factors are proteins that signal tissue repair. That occurs by stimulating cell growth, cell differentiation (formation of different types of cells) and tissue repair. Tissue repair involves removal of diseased tissue and its replacement with healthy tissue. We generally explain that ESWT is a two part process: stimulation of breakdown of bad tissue followed by creation of good tissue although the processes can occur simultaneously. The addition of growth factors can accelerate the second half: tissue regeneration.
One of the earlier means of providing growth factors was by use of PRP or platelet rich plasma. The involves drawing blood and removing the portion of plasma that contain platelets. Platelets are involved in the clotting mechanism but also are a source of growth factors. Stem cells are the most concentrated source of growth factors although the process of extracting stem cells is a bit involved and expensive. Growth factors of stem cell origin can be obtained from other sources. There have been ethical questions with respect to embryonic stem cells but not so for amniotic stem cells. Amniotic stem cells are present in amniotic fluid and amniotic membrane.
Amniotic stem cells contain naturally occurring anti-inflammatory agents such as cytokines as well as growth factors which stimulate tissue growth. Amniotic fluid is a very concentrated sources of stem cells so its use is more practical than trying to extract stem cells from a patient’s own bone marrow or fat cells. Amniotic fluid is “immune privilege” which means that rejection of the fluid is rare. The use of the amniotic stem cells source safe, effective and well researched. The end product used has few stem cells but retains the necessary growth factors. All amniotic stem cell donors go through a rigorous screening process, as determined by the Food and Drug Administration (FDA) and American Association of Tissue Banks (AATB).