|Wednesday, January 26
The knee is composed of tendons, ligaments, cartilage and bone, and its supportive and connective structures work in complex harmony to produce movement in all direction. Perhaps for this reason, across every demographic, in both genders and among all sports, the knee is one of the most commonly injured joints in the body.
From exercising on a stairstepper machine to cutting across the grain on the gridiron, the knee is exposed daily to the rigors of activity -- and the possibility of injury. Today, as the number of physically active people has reached an all-time high, physicians' waiting rooms and appointment books are filling up at an unprecedented rate. The doctor's challenge -- getting the athlete back into action as quickly as is safely possible -- remains the same.
What has changed is the availability of surgical alternatives for the knee, so that the physician, and the patient, now have a number of options for best treating knee injuries. "A number of new, minimally invasive procedures that don't damage the muscle of propreoceptive properties of the knee are now available, says Dr. Arthur Bartolozzi, a member of the Association of Professional Team Physicians (PTP) and head team physician for the Philadelphia eagles and Flyers. "Optimally, these will lead to a quicker, safer recovery."
Join Dr. Bartolozzi as he explains a number of these new alternatives and predicts what we may expect in the not-too-distant future.
How are knee injuries typically treated?
Dr. Bartolozzi: We can divide all knee injuries into two categories -- non-surgical and surgical. In the non-surgical area we usually have the sprains of the ligaments and tendons around the knee or bone bruises to the knee. You can get a bone bruise in basketball, football or hockey if you slam your knee into the ground or into the boards. These injuries can be serious and often very painful but rarely require surgery. There are a variety of non-operative ways to treat these types of injuries.
The most common of the operative injuries are those involving cartilage or ligament damage. There are two types of cartilage in the knee that most people are familiar with -- one is the meniscus, which is akin to a washer that absorbs shock between bones, and the other is the surface coating cartilage, which is similar to a coat of paint that protects a wall. Problems with these areas can lead to surgery as can the more well-known ligamentous structures such as the ACL (anterior cruciate ligament) and to a lesser degree the PCL (posterior cruciate ligament) and the much less common MCL (medial cruciate ligament).
Is the MCL less commonly injured or less commonly treated through surgery?
Dr. Bartolozzi: The MCL is the most common knee ligament injury in sports. It is the ligament on the inside of the knee and it's injured most often from a hit to the outside of the knee, which stretches the inside ligament. In football, it can result from an illegal clip or in soccer it can happen from an aggressive side tackle. In the past, MCL injuries were dealt with surgically. Today, we know that conservative treatments for MCL injuries, such as rest and bracing, can be just as effective as surgery, if not more so.
What about the ACL?
Dr. Bartolozzi: In a knee with a torn ACL, there is an increased risk of injury. These reinjuries usually involve the meniscus or joint surface cartilage. Although not all sports are as dependent on an intact ACL, it is certainley preferable to have a normally functioning ACL. In sports that involve a lot of cutting or pivoting like basketball or football, the ACL is critical. I also think that there are a few hockey players who are playing without ACLs in their knee -- they use braces. They can play their sport on ice where most of the movement is predicated on the straight blade of the skate, although this is becoming more dangerous as body contact increases and the condition of the ice deteriorates throughout the game.
What are some of the treatment alternatives?
Dr. Bartolozzi: One of the great things to happen with knee treatments over the last 10 years or so is the advancement of arthroscopic techniques. As a result, the athlete can come back to his sport so much more quickly, in a span of two months sometimes. Although this is quite common, one of the newer things were doing with knees in conjunction with the arthroscope is a device originally used to shrink tissue in the shoulder. It is a type of heat probe that shrinks the tissue around the capsule of the shoulder to tighten up a "loose" shoulder. It would be analagous to putting a wool sweater in the dryer.
If there is 70 to 75 percent of the ligament left after a tear, it will heal in a lengthened position if left untreated. This technique has been used in the knee with varying degrees of success. It has been very effective with certain people, usually lower demand athletes that have a partial tear in the ACL. One advantage to this technique is that we can tell right on the operating table whether the knee tightens up or not. But because the technique is new for knees, two questions remain -- 1) How much of the ligament needs to be intact for the procedure to be a success, and 2) Does the shrunken tissue stretch out over time?
There has also been a lot of publicity about using cadaver tendons as substitute grafts. Years ago, there was some adverse publicity because the cadaver tendons were sterilized with a chemical which caused joint inflammation. Lately there has been concern about the transmission of disease. It's still not the gold standard. Overall, though, with the advent of tissue banks and the resultant screening criteria, there has been more acceptance of cadaver tissue.
There are also new anaesthetic techniques as well. There are now infusion devices that let us put anesthesia directly in or around the knee joint for several days after surgery, which lets you move the knee more quickly because there is less pain. Getting the knee into full extension is important to insure a good result. Early motion is helpful to clear the knee of blood and fluid and this has been aided by continuous passive motion (CPM) machines.
This treatment advance has had a great effect on recovery rates. We've found that the old method of putting patients in casts and keeping their knee rigid led to muscle atrophy and knee stiffness. Now the emphasis is on early motion, which we've found can be an essential part of rehabilitation. On the other hand, we have to be very careful when doing these procedures and others, like grafts from one region of the knee to another, that we are not compromising one area of the knee for another for the sake of faster recovery.
What about cartilage injuries?
Dr. Bartolozzi: In the past, when we spoke of cartilage injuries we were talking about meniscus problems. It was a hard injury to diagnose before we had MRI tests. Unlike X-rays, which only look at the bone, MRI can give an image of soft tissue structure like ligaments and cartilage and can image swelling inside the bone itself. MRIs are very sensitive and sometimes the images or problems defined by MRIs do not correlate with the patient's problem. For example, not all meniscus tears cause symptoms, so that if an MRI shows a torn cartilage but the patient has symptoms of tendinitis, this has to be sorted out by the treating physician. So, MRIs don't always show what you need to treat or operate on. But it does help with the diagnosis. Removing the meniscus was and is a bad situation because it will eventually lead to arthritis in years to come. Once again, arthroscopy has helped because only the torn portion is removed whereas before the entire meniscus was removed. The meniscus can also be repaired or sewn with new arthroscopic techniques.
Recently, developments have been made that allow us to repair the cartilage from the inside by internal stitching or barbs the keep the unstable cartilage in position while it heals. This is still a bit controversial in that the cartilage has the chance of re-tearing. The re-tear rate can be as high as 30 percent, which is high for a professional athlete but may be an acceptable risk rate for a weekend warrior.
Surface cartilage problems are among the most difficult problems we have to treat in professional and amateur athletics. Recently, there have been researchers in Sweden that have had success with re-growing cartilage but we aren't quite there yet. These techniques are being actively investigated. There have also been procedures where we take cartilage from one part of the knee and transplant it to an injured area.. All of this is very new and very exciting.
Any final thoughts on surgical alternatives and the knee?
Dr. Bartolozzi: Regardless of the treatment, our No. 1 goal is to get people back as quickly as is safely possible. This is usually a matter of the athlete's biology, physiology, psychology and the physician's skills and techniques. There is no substitute for good surgical judgement and experience. Also, just because a technique is new doesn't mean it is good! What we are trying now and in the future is to perfect minimally invasive procedures that don't damage the muscle or propreoceptive properties of the knee so that the patient recovers faster and better. We are entering the era of biological repair and regeneration aided by significant advancements in diagnostic and rehabilitation techniques.