The Need for Good Knees How to take care of these vital, yet vulnerable, joints Today's Health & Wellness July/August 2002 © by Gary Legwold While playing high school football years ago, Nicholas A. DiNubile, M.D., was clipped in the left knee. The medial collateral ligament was torn and there was a slight fracture and dislocation of the patella. Or, in medical terms, "The knee was whacked pretty good," says DiNubile.          After more whacks in college pick-up football games, DiNubile, now 49 years old, went to a physician, who put the left leg in a cast for eight weeks. No surgery, no physical therapy, just immobilization and then gimping back to normal activity after the cast was removed.          This treatment carried DiNubile through his 30s. Taking no mercy on the knee, he ran, played competitive tennis, and did some white-knuckle downhill skiing. However, in his early 40s, he says he began to "notice" the knee as he pivoted on the tennis court. He needed to rest the knee for a day during ski vacations. He replaced running with activities that are kinder to the knees, such as cycling, walking, and elliptical machine workouts.          Today, "I accept my knee limitations," says DiNubile, orthopedic consultant to the Philadelphia 76ers and Pennsylvania Ballet. "I have a wear-related problem and probably some post-traumatic arthritis. There's some grinding and clicking inside, and I should have arthroscopy done to clean things up. But I don't. Typical doctor, I guess."          Many of us are like DiNubile: We've had our knee dinged up in our salad days, and now we are "noticing" the knee and reluctantly accepting whatever limitations that are popping up. The problem is this acceptance can cause an unhealthy, sedentary life-style and is often the result of an assumption from the past: Knee problems meant major surgeries and minor hopes of full recovery. However, several new treatments and procedures offer knee-pain sufferers relief and the possibility of activity without limitations. Good Health, Bad Knees           One could make the argument that the knee is a casualty of the fitness movement. As more people become more active in order to reap the many benefits of exercise, their heart, lungs, bones, muscles, and mind become healthier—at the expense of the knees.           "We are seeing an increase in early arthritis in knees of people in their 40s and 50s." says James Garrick, M.D., orthopedic surgeon and director of the Center for Sports Medicine at St. Francis Memorial Hospital in San Francisco. He says before the fitness boom, now in its fourth decade, and before the increase in sports participation by females, many arthritis conditions were associated with old age, not middle age.          Exercise, orthopedists explain, means weight-bearing movement (unless you swim), and this movement means repeated pounding on the knee with forces up to four to five times body weight. Over decades of exercise, this can mean a lot of wear-and-tear and the development of ligament and cartilage damage, kneecap dislocation, loose bodies in the knee, osteoarthritis, and overuse conditions known as runner's knee and jumper's knee.          Doctors usually are willing to let patients risk possible knee damage in exchange for the many benefits of moderate exercise. "Being sedentary is more dangerous than smoking a pack of cigarettes a day," says DiNubile. "There is a huge potential for risk when people do not exercise."          Like DiNubile, Garrick does not want a patient's concern about potential exercise-related knee problems to contribute to a sedentary life-style and the possible resultant health problems, such as a failing cardiovascular system. Exercise to your heart's content, he says, but don't take your knees for granted. Instead, take care of them by following the advice below. Taking care of knees now will pay off especially as you age. "When you are older, a knee problem is not just a knee problem," he says. At that stage of your life, you may increasingly rely on exercise to maintain low blood pressure and avoid diabetes and heart conditions, "and a bad knee can prevent you from exercising." Use your head and save your knees           As we explain in the next section, there are many new treatments and procedures doctors offer for your ailing knees. But if you follow the 10 tips below, your knees may last a lifetime without your doctor's medical or surgical intervention. Stay strong. Garrick says the best way to prevent knees from going bad is to maintain the strength of muscles supporting the knees, particularly the thigh muscles. Quadriceps support takes some of the strain off the joint. He sees patients who are in a vicious cycle of knee pain leading to weakness (or is it the other way around?), which leads to more pain and then more weakness. "But if you get those quads strong again," he says, "it's amazing how often symptoms diminish or are eliminated." Mix it up. Cross-train by participating in a variety of activities each week. Focusing on one activity can be boring and lead to activity-related repetitive injuries to knees. Cross-training also applies to children, who often are playing basketball, soccer, or hockey year round. "These kids can drive themselves too hard," says DiNubile. "They play like adult professionals and then develop adult-like, overuse injuries because of it." Stay active. Don't fall prey to the weekend-warrior syndrome. Compressing your workouts into a day or two on the weekend sets your knees up for trouble and doesn't do much for your fitness. "Many people between the ages of 20 and 40 find a job, get married, have kids, and the next thing you know they are fat and lazy," says Jon Schriner, D.O., medical director at the Michigan Center for Athletic Medicine in Flushing, Michigan. "Then they play hoops with their 20-year-old kids to show them what they were like when they were young. Not only isn't their game there anymore, but they often blow out a knee, an ankle, or an Achilles tendon." Bottom line: Work out at least three times a week. When you increase your activity level, do so in increments of no more than 10 percent per week. Avoid risky activities. If you are into such knee-jarring activities as ski jumping, sky diving, downhill skiing, and football, then consider activities that are kinder and gentler to knees. This is true especially for youngsters. "If you have a significant knee injury when you are young," says DiNubile, "you are five times more likely to have osteoarthritis of the knee when you get older." Lose weight. Being overweight accelerates existing osteoarthritis because extra weight means extra pressure on the knee. Remember, forces on the knee can reach four to five times body weight with exercise. "So, if you lose just 2 pounds," says DiNubile, "the knee senses less force and ‘thinks' you have lost 10 pounds. I know my knee tells me I have lost weight before my belt size does." Have good "shock absorbers." Don't keep wearing those same old athletic shoes you've worn for a year because you like the color or are too cheap to buy new ones. The midsoles, the shock-absorbing part of the shoes, are shot and your knees are taking more punishment than necessary. Buy new shoes often. Change walking and running shoes, for example, after 400 to 500 miles of use, or in six to nine months. Take lessons and invest in good equipment. Learning proper techniques in a sport can save strain on the knees and help you avoid overuse injuries. And having proper-fitting, sport-specific shoes, kneepads (for hockey, football, baseball), a bike that fits your body size, breakaway bases in baseball, etc., will help prevent knee injuries. Seek professional help—before you need it. Orthopedists, physical therapists, chiropractors, and athletic trainers can analyze your gait, customize workouts according to pre-existing knee problems, and help fine tune your exercise program so your knees are treated nicely. Add activities and new exercises cautiously. No matter if you have been sedentary or you exercise, think about the specific movements of whatever new activities you are considering. Are these movements gentle on your knees? How much time are you allowing to ease into this activity? "I tell my athletes that track season, for example, starts in January, not in March, which is when the season officially opens," says Schriner. "Gradually preparing for the season would prevent a ton of knee injuries, especially in female athletes [see sidebar]." Rest. Listen when your body is barking: "Cool it!" This means allowing time for recovery and adapting to new activities. Cross-training helps rest sports-specific muscles and joints, but sometimes the best medicine for the knees is just kicking back for a day. Facts about females and knees (sidebar)         According to the American Academy of Orthopaedic Surgeons (AAOS), female athletes in high school and college have a three to four times greater risk of sustaining a serious knee injury than their male counterparts. Focusing on two sports, the AAOS found: The incidence of anterior cruciate ligament (ACL) injuries among female basketball players is twice that for males. Nearly 60 percent of ACL injuries in female basketball players occur when landing from a jump. Female soccer players are four times more likely to suffer an ACL tear than their male counterparts.         Most ACL injuries occur in females aged 15 to 25, and orthopedic researchers have long debated why females are more at risk than males. They have yet to come with solid answers, and more research is needed. According to one theory, menstrual cycle hormones may weaken ligaments. Females tend to land on a flat foot rather than their toes, which can contribute to increased injury rates. Also, females tend to have an imbalance in the strength of their quadriceps muscles versus hamstrings; this imbalance may increase the risk of ACL injuries. Finally, the angle of the thighbone connecting to the knee is often wider in females, creating forces on the knee that are different than with males. From the doctor's office         Twenty years ago, a visit to an orthopedist about your knee was a grim appointment. In effect, it meant the end of your athletic career. Your future featured a major surgery, big scars, a year of rehabilitation, reduced function of the knee, a limp, more surgeries in many cases, and osteoparthritis.         Then in the mid-1980s, the picture brightened with the widespread use of arthroscopy. This surgical procedure allows a surgeon to diagnose and treat knee disorders by providing a clear view inside the knee. Surgeons make small incisions to insert into the joint a pencil-sized instrument called an arthroscope. The scope contains optic fibers that transmit an image of your knee through a small camera to a television monitor. The TV image allows the surgeon to thoroughly examine the interior of your knee and determine the source of your problem. During the procedure, the surgeon also can insert surgical instruments through other small incisions to remove or repair damaged tissues. Today, arthroscopy is one of the most common orthopedic procedures, with more than 1.5 million knee arthroscopies performed in this country each year.         Because the puncture wounds are small and pain in the joint is minimal, recovery is often a matter of days or weeks. "Before arthroscopy," says DiNubile, "we would put a patient in a cast for 8 weeks and then there would be a year of rehab. Now, there is no cast and no immobilization. I've had patients—three days after the arthroscopy—walk into my office without a limp."         Since the advent of arthroscopy, the knee-repair world has continued to brighten. Below is a summary of treatments doctors can offer patients in need of relief. U>Glucosamine and chondroitin sulfate         The AAOS says about 30 million Americans suffer from osteoarthritis. Many of these people are finding relief in dietary supplements such as glucosamine and chondroitin sulfate.         Glucosamine stimulates the formation and repair of articular cartilage (cartilage at the end of bones). Chondroitin sulfate prevents other body enzymes from degrading the building blocks of joint cartilage. Both are found naturally in the body. People who use these nutritional supplements hope they will relieve the pain of osteoarthritis, and perhaps even repair or restore the joint cartilage. Garrick says two-thirds of patients experience a positive effect from these supplements.         Glucosamine and chondroitin sulfate have been used in Europe for several years, with few reported side effects. Both supplements also have some anti-inflammatory effects that may account for the pain relief. DiNubile says he prescribes Cosamin DS, which is a purer form of glucosamine and chondroitin sulfate. Viscosupplementation         Viscosupplementation is injecting hyaluronic acid into the knee joint. Hyaluronic acid is a naturally occurring substance found in the synovial (joint) fluid. It acts as a shock absorber and lubricant to enable bones to move smoothly over each other.         In treating knee osteoarthritis, doctors first use pain relievers such as ibuprofen or nonsteroidal anti-inflammatory drugs (NSAIDs), along with physical therapy, topical analgesics, and injections of a corticosteroid. Viscosupplementation relieves pain in many patients who react to NSAIDs or do not find relief from non-medicinal measures or analgesic drugs.         The technique has been used in Europe and Asia for several years, but the U.S. Food and Drug Administration did not approve it until 1997. Two preparations of hyaluronic acid are available: a natural product made from rooster combs, and an artificial one manufactured from bacterial cultures. If you are allergic to egg or poultry products, use the manufactured product. Osteochondral grafting         A plug of bone and healthy cartilage is harvested from one area and transplanted to the injury site. The plug must come from a non-weight-bearing area that has little contact with other bones. This fact usually limits its application to treating smaller lesions. Autologous chondrocyte implantation (ACI)         In this two-step procedure, surgeons first use arthroscopy techniques to harvest chondrocytes, which are mature cartilage cells, from a healthy, non-weight-bearing area of the knee joint. These cells are then treated so they will multiply over several days.         In the second surgery, the surgeon cleans the injury site and removes a piece of the soft tissue that covers the tibia. This tissue is sutured and secured over the injury, and the cultured chondrocytes are then injected beneath the patch. There, the chondrocytes eventually produce a form of cartilage that is very much like the original.         Because ACI uses the patient's own cells, there is no danger of rejection by the immune system. Complications are rare and, in most cases, the procedure results in a restoration of joint movement without pain. However, ACI works best for small areas of cartilage damage. "We use this to fix the ‘pothole' but not to repair the whole ‘road,'" says DiNubile. Mesenchymal stem cell (MSC) regeneration         MSCs are "undifferentiated," which means they have not yet developed into a particular type of cell (such as bone or muscle). Research suggests that MSCs can be withdrawn from the individual's bone marrow, placed in a gel matrix, and implanted at the defect, where they develop into new cartilage. More research is needed before this procedure is commonly done. Minor surgical procedures          DiNubile says surgeons now use bioabsorbable tacks to repair some cartilage tears. Also, surgeons can do a microfracture, a procedure of poking holes in the damaged cartilage area. The bone beneath the cartilage bleeds, creating an environment that causes cartilage scar tissue to form.         The AAOS says about 10.8 million visits are made per year to physicians' offices because of a knee problem. It is the most often treated anatomical site by orthopedic surgeons. You may be lucky and not have to see a doctor about your knees, especially if you follow the knee-care tips in this article. But if you do require treatment, your timing could not have been better because new procedures offer hope to hurting patients. As Garrick says: "We have tools now that we did not have a decade ago." Gary Legwold is a Minneapolis-based health writer who has avoided surgery to his left knee by taking glucosamine and chondriotin sulfate. Back Gary Legwold glegwold@lutefisk.com (612) 926-1877 "Ideas Need Words" Home Page © Copyright 2004 Gary Legwold and Conrad Henry Press. All rights reserved.