Cartilage Regeneration

New Osteochondral Plugs for Cartilage repair

2008-02-03T12:57:00.000-08:00

Next month I will be using a new type of plug, made from allograft bone and cartilage, to replace damaged areas of the knee joint. Allografts have been available for some time, and are not experimental; the problem has been that in order to get live cartilage cells the grafts have to be fresh- and this has led to contamination problems with both bacteria and viruses.

The new plugs are based upon a new freezing technology that allows us to freeze the graft without ice crystals forming. About 50% of the cartilage cells live, and survive in the recipient. The grafts are prepackaged in the shape of a cylinder. The cost of these plug is far less than the cost of an ACI transplant.

The company making the freezer is Core Dynamics, have a look at their web site.

Stem Cells and the Candidates

2008-02-02T12:12:00.000-08:00

Just before 9/11, President Bush made a televised speech about stem cells and how to restrict federal funding based upon existing lines in culture. Amazing how little is heard about this issue now in the debates, particularly on the Republican side, where it seems most people just want the issue to go away. Well it might or it might not. Recent advances in generating stem like cells without using embryos are promising, but not conclusive (see prior post). Like most issues in science, there will be progress and then setbacks. The main lesson from this impasse seems lost; the government does not "control" science, but it sure can makes things difficult.

Stem Cells Redux

2007-12-16T09:25:00.000-08:00

Sometimes after a false start- such as the data fiasco in Korea- the science eventually catches up. So the early report of reprogramming skin cells to behave like stem cells has now been confirmed in humans, and then duplicated by another lab-using a slightly different set of genes.
So it looks like it works. This means we may be able to get a supply of cells that act like stem cells without dealing with embryos whatsoever. That would be a leap forward, especially for those reserachers who are dependent upon NIH policy decisions dictated by the White House.
In effect, it will depoliticize the field.
Next on the agenda- make sure the new programming tools do not, for example, make these cells into cancer cells.

Stem Cells from the Skin

2007-06-08T12:53:00.001-07:00

This week the headlining news has once again to do with the production of Stem Cells- this time without using any embryos.
Skin cells (in the mouse) have been reprogrammed using a a small number of "transcription factors". These are small proteisn that control the expression of bits of DNA. What is remarkable is that a only a few signals were needed to make a major change in the cells. And the
work was duplicated by several groups- making it far more believable.
Lots yet to be done to make anything similar work in the human. I have personal experience
working with insulin, that clearly showed major differences between mouse & human. So stay tuned.

New Paper on Cartilage Glue

2007-05-03T13:28:00.001-07:00

New technology from Johns Hopkins promises to "glue" new cartilage
to the the surrounding cartilage, giving us the prospect for integrating the repair tissue with the good tissue around it.

clipped from clipmarks.com

clipped from www.nature.com

The promise of supplements

2007-04-17T09:23:00.000-07:00

I get lots of questions from patients with joint disease about nutritional supplements- the type of stuff available at Costco in a large bottle. None of the stuff in these pills has ever been proven to get to the joints- like many vitamins, it just goes out the GI tract. So the issue is, this is probably a waste of money. Even doctors have been taking the stuff- but of course they are people too, and everyone is looking for a free lunch. Remember St. Johns's Wort (for depression)? Someone- I think Osler- once said you have to use a new medicine real soon, before it loses its efficacy. There is a high "placebo effect", be aware of that.
As to safety, I also get concerned that chondroitin in supplements is not from cows that have been tested for mad cow disease- it is not regulated. That is why this material is not sold in a pharmacy etc. So caveat emptor!

California to (Maybe) release Stem Cell Money

2007-03-07T17:14:00.000-08:00

California has several years ago voted to fund Stem Cell Research, thanks to lack of support from the Feds (and specifically the White House). But the anti-Stem forces have stymied the funding in every legalistic way they can. A recent ruling from the California Appeals Court has freed up the money, which has been appropriated by the State. The total is 3 B over a period of time; so far the big winners are Stanford and UCSF, no surprise, but the money is disseminated around the State. Stay tuned to see if there is an appeal to the Supreme Court of CA; it ain't over till it's over.

Different Kinds of Stem Cells

2007-02-18T13:41:00.000-08:00

The political and scientific status of adult stem cells (also called mesenchymal stem cells, or MSCs) and embryonic stem cells (escs) is quite different and in need of constant clarification. Add to these two types of cells amniotic stem cells, recently discussed by Anthony Atala (Wake Forest) as another possible source of different- and still useful- cells that are normally discarded in amniotic fluid. But there are many more types. Even within our bone marrow, stem cells have begun to differentiate into subtypes. Catherine Verfaille has identified "multipotent" cells, that can make certain tissues such as muscle, cartilage & bone (MAP stem cells); but these cells cannot make, for example, liver or bladder. The different types of stem cells will eventually be classified based upon surface antigens or other biomarkers that give us an idea of what path they have already gone down...and what they can become.

News from the Orthopaedic Research Society

2007-02-17T05:07:00.000-08:00

The recent ORS meeting in San Diego featured pretty good weather and lots of stuff about cartilage from contributors around the world. It will take several posts to summarize. Lots of people were talking about the Osiris study on using injectable stem cells for regeneration of the meniscus, which is the cushion of the knee joint. Non medical people sometimes call this the "cartilage", but I will call it the meniscus; the cartilage on this blog is the surface coating of the bone. Anyway, the cells did nada for the meniscus, which is too bad, but the investigators noticed there was some improvement in the cartilage, which is interesting. These are allograft stem cells, they come from a dead donor. I don't know if the injected cells seed themselves and grow, or if they just produce some chemicals (growth factors) that diffuse around the knee and help the other cells. This type of "co-culture" effect has been seen in the lab in other situations. Anyway, if there is something positive put out by the injected stem cells, that would be very, very interesting.

Cartilage Regeneration

2007-02-04T13:37:00.000-08:00

Cartilage Regeneration
Orthopaedic Research Society
The ORS is to meet next week in San Diego for it Annual Meeting.
Expect many papers concerning stem cells, joint repair, cartilage
regeneration and growth factors. Many vendors use this meeting to bring
out new products. New forms of allograft material may be introduced this
year that are both safer and easier to use than prior techniques. Keep an eye on cell based
products that may be easier to deploy that older methods of ACI.

Using Chitins for Cartilage Repair

2006-10-24T14:31:00.000-07:00

Another interesting approach to cartilage repair is to take advantage of the biologic
similairy between chitin, part of the exoskeleton of lobsters and crabs, and chondriotin sulfate, part of the human cartilage matrix. The chemical similarities are closer than you might think. BioSyntech, (www.biosyntech.com) in Canada, is conducting a trial where the chitosan chemical is bound to a small blood clot and "sticks" into the cartilage lesion. The cartilage is also microfractured at the same time. The idea is to help the stem cells in the bone marrow stick to the cartilage defect and, hopefully, turn into some sort of cover resembling natural cartilage. A nice study has been done in sheep showing some promise for this technique.

Now listed on Technorati

2006-10-24T14:22:00.000-07:00

I am pleased to tell all that this blog is now listed on Technorati for your convenience. Technorati Profile

New trial from JNJ

2006-10-23T20:18:00.000-07:00

Another new, unproven technique to rebuild cartilage is being tested. This one, called CAIS, uses a small piece (biopsy) of a patient's normal appearing cartilage and place it in a matrix- sort of like a jelly- then puts it back into the knee. The cartilage iis "minced" up during the procedure, but not expanded or grown. This is in contract to the ACI approach, which uses tissue culture as a means of expanding the cartilage. It is therefore less expensive. So far only a few patients have trialled this new procedure so it is far too early to tell about uts success.

Cartilage Regeneration

2006-09-22T17:03:00.000-07:00

Cartilage Regeneration
More News on Microfracture
New information keeps coming out on this popular technique, the latest showing perhaps an 80% chance of
success- depending upon how you define success, of course. The science has not yet caught up to the clinic. When you ask a patient how they feel, that is one thing- when you actually have evidecne of cartilage regeneration, that is quite another. These two things do not necessarily correlate. And another area of concern is that presently most work is done on patients who are already in pain. The optimal time to repair cartilage may be way before this occurs.

Stem Cells in the news

2006-09-04T15:25:00.000-07:00

The news on stem cells just keeps on coming, and will continue to do so. Last week,
the notion from a private lab in Mass. that is is possible to take out just one cell from an embryo at a very early stage and develop a cell line without destroying the rest of the embryo. I think they soft pedalled the fact that in this particular context, the entire embryo was a discard anyway- which is the case quite often given the extra embryos produced by in vitro fertilization.
The FDA recently gave in on the "morning after" pill, so perhaps there is hope for the future even with this administration (I doubt it). But the news will continue...

InnerVue Instrument for viewing Cartilage

2006-05-17T18:20:00.000-07:00

Once in a while a new technique appears that promises to make diagnosis a lot easier.
The InnerVue scope ( from Arthrotek) may be one such new instrument. Under only local anesthesia, a very samll tube is put into the knee. It contains 17,000 fiberoptic channels, and is able to give a pretyy good picture of the joint. This may eliminate the need for MR scans,a nd give immediate visual information to help decide what therapy is needed. it also may be a great way to monitor cartilage repair.

Glucosamine Posts

2006-04-23T17:27:00.000-07:00

I have noted quite a number of net resources advocating glucosamine for damaged joints, including osteoarthritis. Glucosamine is basically a sugar molecule with substitutions, and in culture it may be very beneficial to the cartilage cells that make the matrix we walk upon. So glucosamine is a good thing. BUT....there is really no evidence I know of that shows orally administered glucoamine gets to the target; that is the joints. Don't forget, everything we eat must go thru the stomach etc., hopefully wind up in the blood, and then be carried around the body. So supplements do no good unless they get to the target.

Problems with Microfracture

2006-04-23T17:17:00.000-07:00

Microfracture as a method of cartilage repair has been much in the news lately.
Some celebrated athletes, including a major player for the Phoenix Suns, have had the procedure with decidely mixed results. Granted, the requirements of a NBA player are substantial, but according to the NY Times 9 out of 13 cases have failed to return to sport. In some cases, a return to athletics was attempte4d within about 6 months, which is far shorter than the originators of the technique have proposed. Nevertheless, there is no clear evidence that microfracture really works in a reliable way.
It would interesting to know of a comparable sample of players who have had cell based therapy, such as Carticel ( ACI).

Cartilage Regeneration

2006-04-23T17:15:00.000-07:00

Cartilage Regeneration
MICROFRACTURE FAILING IN ATHLETES

Osteochondral allografts or autografts

2005-11-26T14:06:00.000-08:00

Another way to patch up cartilage is to take a plug- usually of both bone and cartilage- from either a tissue bank (cadaver) source or from another area in the knee.
There are problems with both of these donors, however. The tissue bank solution is appealing- until you read about disease transmission, including death, from tissue banks. The most celebrated incident occurred in St Cloud Minn a few years ago, and it could happen again. Only this year (2005) did the government start monitoring these tissue banks- and that effort is not problem free.
The other source of these plugs could be your own knee- using an area on the periphery. But for very large defects it is hard to rob Peter to pay Paul.

New Efforts to restore cartilage

2005-11-26T14:04:00.000-08:00

Check out www.cartilix.com to look at a new startup in the field.

Microfracture

2005-10-24T09:47:00.000-07:00

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

2005-10-17T16:25:00.000-07:00

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

2005-10-12T10:45:00.000-07:00

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

2005-10-10T04:34:00.000-07:00

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

2005-10-09T10:19:00.000-07:00

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.