Repair of Torn Knee Joint Cartilage With BIOSTINGER             As arthroscopic surgery has evolved over the years techniques have changed for treatment of torn joint cartilage. In the early days of arthroscopic surgery it was common to invariably remove all of the torn portion of cartilage from the knee joint no matter how large the torn portion was.     The cartilage or meniscus as it is known medically, is an important shock absorber and protector of the knee joint especially the articular cartilage. The articular cartilage is the covering over the ends of the bones in movable joints. It is also known as hyaline cartilage. This is very different from the cartilage which patients commonly refer to in the knee joint, which is correctly termed the meniscus.     At any rate we are obliged to continue to refer to the meniscus as the knee joint cartilage because this is the term which almost all of our patients understand. After many years of experience it became obvious that preserving the joint cartilage was important if it could possibly be done.     In the 1980's a number of techniques were developed for actually suturing the joint cartilage and repairing it. It was almost always done by open methods. Eventually instruments became available in which sutures could actually be tied within the joint and this ushered in a new way of repairing the joint cartilage, but not actually needing to open the knee joint in the traditional sense with a large incision. These techniques were done with the arthroscope.     In more recent years repair methods have been developed utilizing absorbable materials which can hold the torn cartilage pieces together. Over time it allows the body to repair the torn cartilage as it would other tissue. Healing of course occurs with scar tissue formation uniting the torn portions of cartilage.     One of the interesting techniques for repairing torn cartilage is with a device called Biostinger. This implant is made of a material, PLLA, and has multiple rows of barbs to keep it from pulling out of the cartilage during the healing time.     It is inserted into the knee with special instruments so that it may accurately placed where it is needed within the knee joint. It comes in different sizes.     Repairing the cartilage can only be done in an area of the knee in which there is a chance that the cartilage will heal back together. This occurs in the area of the cartilage, which is more close to its attachment to the tissues of the capsule of the knee joint. If the cartilage portion is too small or too far in the joint or is torn in shredded way it is not possible to repair it. These torn pieces of cartilage are better removed.     After a cartilage is repaired the patient is required to use crutches and to be partially weight bearing for considerably longer (average one month) than if the torn portion is simply removed. Immobilization is also required so that the knee may rest during the healing period. This is followed by a period of rehabilitation to allow for further healing of the repaired joint cartilage.     Biostinger implants have been an important advancement the treatment of torn knee joint cartilage. This should be viewed as a stop along the way as other materials and other implants are developed in an attempt to pave the joint cartilage if at all possible.