Surgery-Free Fix Knees -- In Depth Doctor's Interview
Preston Wolin, M.D., from Weiss Hospital discusses knee injuries and a new alternative to knee replacements.
What does a knee look like?
Dr. Wolin: There is the femur, or the thigh bone. There is the tibia, the shin bone. Between the two bones of the knee are two washers, each of those is called a meniscus. Between the bones connecting them are structures and those are the ligaments. In the middle of the knee there are two of them that make a cross. One crosses from the back to the front and that is called the anterior cruciate ligament, and the other one stays in the back and that is called the posterior cruciate ligament. Now, on the ends of all of these bones, on the femur, on the tibia, on the kneecap, is a whitish material and that is called articular cartilage. It is the same material that you will see on the end of a chicken bone. It is normally white, it is normally smooth, and it is normally glistening. All of these things have to work together to produce a normal knee.
What happens when there is a subchondral defect then?
Dr. Wolin: When there is a subchondral defect there is force that is applied to the bone below the surface, and subchondral means below the chondral surface or below the level of the articular cartilage. Commonly, it occurs either in the femur or it occurs in the tibia and almost always it is a result of an injury taking place to either the meniscus, where you lose the weight bearing portion of the meniscus, or you have an injury to the articular cartilage, the cartilage on the end of the bone, and the bone below it sees more stress.
What kind of injury would cause that?
Dr. Wolin: Any that results in injury to the meniscus, to the anterior cruciate ligament, and to the articular cartilage.
How long would it take until you really started feeling that you needed to have a procedure?
Dr. Wolin: Most injuries will get better after a while. That is what we call the honeymoon period, when you have not tried it out and you may not try to run, you may not try to cut. If you do develop one of these subchondral injuries you are probably going to notice it in say weeks and definitely over months. As time goes by you are going to notice it more and more.
Is it just sore or is it a sharp pain? What do the patients feel?
Dr. Wolin: I have had patients tell me that it is like a toothache every time they try to walk on it. Certainly if they try to run or they jump on it, then it will get worse after and with repetitive activity.
When they come in and you find out that is the problem, what was the standard treatment for that?
Dr. Wolin: Most of the time if we eventually end up seeing that, doctors will say rest. Give it time. It is a "bruise" in the bone and it will heal.
But it doesn’t heal?
Dr. Wolin: A lot of times it does not heal, especially if it is combined with other injuries. If you have a patient who comes in and tells you that they have had that problem for years, it is probably not going to heal.
What is the next step?
Dr. Wolin: The next step is to identify that area, and the best way of doing that is an MRI scan.
A lot of people have to end up with total knee replacements, is that right?
Dr. Wolin: Well, the standard answer has been to date that eventually those patients are going to need to have knee replacements because the problem will continue and there is usually loss of the cartilage on the end of the bone. So the traditional answer has been a knee replacement in many cases.
That is a major procedure?
Dr. Wolin: It is a major procedure to the patient, first of all. It is a major procedure to the bone because what is happening is that the normal bone is being cut away with the cartilage overlying it and being replaced by basically some metal and some plastic.
What is the recovery time on something like that?
Dr. Wolin: For a knee replacement? Well, patients are commonly in the hospital for 3 days. They will go home and they will stay at home for several weeks, or they may need to go to rehabilitation facility for 3 or 4 weeks, something like that. They will need rehabilitation and the structured rehabilitation can take anywhere from say 4 to 6 months.
Are out for a while if you are an active person?
Dr. Wolin: It is a significant time period away from normal activities. It is a longer period of time away from sporting activities, like golf or maybe tennis.
Do you find people just decide not to do it because of the time they will be out?
Dr. Wolin: Yes. Another major factor is the sacrifice of not being able to go back and do the activities that they like to do. Most doctors who do knee replacements are going to recommend avoiding against loading sports where they will be jumping, they will be twisting, they will be cutting. Lower level sporting activities such as bike riding or golf are allowed, but something like returning to playing basketball is not generally accepted as an activity to do after knee replacement.
How long have you been working with subchondroplasty?
Dr. Wolin: I have been doing this now for about a year, and the experience that we have actually comes to us from Europe. There have been a large number of cases done in Europe, more than 500. There are centers where this is being done in the United States and there have been follow-ups of 2 years plus. For the right patient the subchondroplasty procedure does appear to be a very good and a minimally invasive alternative to either waiting for an extended period of time, or some type of reconstructive procedure that might involve a knee replacement or at least a partial knee replacement.
Can you walk us through the process?
Dr. Wolin: Commonly patients will come with the symptoms that we talked about, this kind of deep toothache type pain and typically they will say that they hurt in the bone below the region of the joint; basically down here. There may or may not be some arthritic changes that you see on the x-ray, commonly not advanced arthritic changes that you see on the x-ray. Then they will have an MRI that will show that there is a collection of, in layman’s terms, "blood" in the region below the bone and what we have come to find out is that this is actually a stress reaction. It may not be an actual stress fracture, but what the MRI is telling us is that that bone is not supporting the load that is being placed on it. The idea in the past has been to take the stress off that bone, say for at least a partial knee replacement. However, what we found now is that there is another way of doing what we want to do, which is to give the patient relief, and that is to shore up the area by giving it more support. What is done is through small incisions is to place some cement directly into that area. When the patient is having the operation in the operating room, it is really important that you get the bone cement, which is absorbable by the way; the body is going to absorb the cement. You need to be sure that you are exactly in the right location. The patient, once they are asleep, has this jig that is applied to them and with an x-ray we can localize exactly the particular area that we want to put the cement in and it is going to show us that we are in the right place. When that pin is in the right place, we leave it there and then will place this little trocar directly over that area and we are going to put it in the bone so that we can inject the bone cement.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
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If you would like more information, please contact:
Preston Wolin, MD
Weiss Memorial Hospital
To read the full report, Surgery-Free Fix Knees, click here.