Abstract

 

In the knee there is a horseshoe-shaped piece of cartilage called a meniscus. The meniscus acts as the shock absorber for the knee, allowing the knee to withstand up to two times the body weight of the person during physical activity. The importance of the meniscus is so great that without it, the knee becomes weak, and the person experiences a lot of pain. The meniscus can get injured when there has been too much stress put on it. If there is a sudden twisting, or impact on the cartilage, the meniscus can tear. Before the medical field even knew how to deal with knee injuries, there was nothing for a patient to do, but to deal with the pain of having a torn meniscus. However, because knee injuries were so common doctors had to come up with some way to fix the knee problems.
The best way to fix a torn meniscus is to undergo arthroscopic surgery. This surgery is very easy to have because the technology is so advanced. The doctors are able to go into the knee and sew the torn meniscus together. However, there are some cases where the meniscus has to be removed. If the meniscus is torn on the outer side of the knee, the piece cannot be fixed because there is not enough blood vessels to help heal the tissue. In this case the piece of meniscus must be removed. After this surgery the pain will go away, and the meniscus will still be strong. However, there are extreme cases where the entire meniscus has to be removed. These cases are due to either a huge enough tear where it cannot be sewn up, or that the person has gone through so many surgeries, where the meniscus has to be removed, that none is left. In these cases the patient has two choices. The first, which is the most common because there are no risks, is to just live without the meniscus and stop most physical activity. The second, which is rare, is a meniscal transplant. These patients are those who want to be as active as they used to be. This procedure is called allografting.
Allografting is so new that doctors usually do not recommend the procedure. However, there are those who have undergone the allografting, and the surgery has turned out to be a success. The purpose of my experiment is to find out how well the allograft cartilage works when put into the knee. The transplant cartilage is freeze-dried, before it is put into the knee, to preserve the tissue. However, there may be some problems in strength after the cartilage has been frozen and thawed out before it is transplanted. The experiment will test the freeze-dried material to see how much impact force it can take verses another piece of meniscus that has not been freeze-dried. These results are important to the patients because they can help those who are undergoing the allografting to learn more about the benefits, if any, of the surgery. If the meniscus is not as strong, once frozen and thawed out, then the point of the surgery is meaningless. However, if the meniscus is just as strong, then patients may want to take on the risk, to gain full strength once again in the knee.