Microfracture

One method of trying to heal cartilage losss is to make small holes in the underlying bone with a pick, or awl. There are stem cells in all adults- all throuhgout life. These cells are not as good at healing as embryonic cells, but nevertheless may still be up to the task. If the holes can
stimulate" leakage of the marrow adult stem cells, then with some luck they may repopulate the area of defect and and "become" cartilage or like carrtilage. Early motion of the joint, is thought to help this change occur.
Microfracture may be more useful for small areas than large ones; also, it may be unpredictable- how is one to know if the stme cells cooperate? if there were some way to guarantee this, or to encourage it along, then microfracture may have an increasing place in the options for this disease.

Techniques for restoring cartilage

The general methods for restoring cartilage, the surface cover of our joints, involve using materials that are either already there or bringing new materials to the repair site. The cells that we are born with are called chondrocytes. One technique, called autologous cell implntation, uses a small biospy of these cells and then expands them in the lab- cloning- only to reimplant them later. Other methods try to take advantage of the body's stem cells, which fortunately are in the bone marrow just below the joint surface. How do these cells (sometimes) know to mkae new cartilage? That is the dilemma- and the possible cure- for many types of cartilage loss.
other issues have to do with the cost of these procedures. It sure would be better to use cells ( adult stem cells) that are alreay present, if you could just convert them into the cartilage that is needed. Many experiments using growth factor proteins are trying to accomplish just that.

New patients with cartilage loss

In today's clinic, I had the chance to see two young patients- both in their twenties, with painful knees due to loss of cartilage. the first had a "hole" affecting the inside of the knee, about 4 sq. centimeters, which is large. We are going to grow some cartilage cells from the patient's body, expand them in culture, and the replace them in the knee. They will then stick to the hole and grow.
The second patient had a similar problem but affecting the back of the kneecap. Unbelieveable, the insurance company refuse to pay for the surgery because this location was not tested when the product went through trials. This is just a lame excuse. So as an option, I am going to take some cartilage from a tissue bank and see if a good repair can be made. More on the hazards of tissue banking later.

The problem with cartilage

Cartilage is a very specialized tissue with relatively few cells and and a lot of "matrix" which is a composite secreted by the cells. The matrix forms a resilent gel, nice & white & shiny; when it cracks or is worn away, there is only bone beneath it. It hurts to walk just upon the bone. Eventually, when there are lots of holes or cracks in the cartilage, the bone starts to try and repair the problem; it does this mainly by making more bone. This causes the formation of "spurs", known as osteophytes, extra bone which is useless. When patients come in with very abnormal xrays, what you find is a narrow joint space, spurs, and bone rubbing upon bone. This is osteoarthritis. THE trick of cartilage repair is to prevent these changes when the cartilage holes are
relatively well contained and before the xrays are terrible.

Welcome to my Cartilage Journal

I am an orthopaedic surgeon with a special interest in repairing cartilage. Over the years, I have arthroscoped (looked inside)
many joints- mostly knee joints- that have worn away the surface of the knee, eventually exposing the bone underneath. This is one way in which arthritis develops. Sadly, older techniques for "repairing" cartilage leave a lot to be desired; some would say they do not work at all.