Ouch! That Hurts: From Symptoms to Diagnogis (part 2)

LOCKING

There are two types of locking, true locking and pseudo-locking. More precisely, there’s what your doctor would call locking and what you would describe as locking.

True Locking

For the orthopedist, true locking doesn’t mean that the knee can’t be moved, but rather that something is preventing it from fully straightening out. It’s like trying to close a door that’s wedged open. Whatever it is that’s wedged in there may slide out of the way (only to remind you of its presence by sliding back again when you least expect it) or it may be a source of continuing trauma.

The key to locking is often a torn cartilage or a loose body (such as a bone chip) that has finally been caught and it has grabbed your attention. The locking of a meniscus, at least on the first occasion, generally occurs while doing something active, like playing football. A loose body lock is more likely to occur during an everyday activity, such as walking downstairs.

“How come l have this torn cartilage and it locked on me and I've never had a major injury?” I hear patients complain. If pressed, some do recall some sort of injury, maybe twenty years ago, but it was “no big deal.” That loose body in your knee may have been off to the side, with everything functioning fine, until that one additional maneuver gave it just enough freedom to ‘get caught. Or perhaps there truly was no one traumatic incident that initiated the whole process. Imagine a carpenter who is constantly squatting. For whatever reason, every time this carpenter squats there is a tear of his cartilage, microscopic at first, then after two years it’s a millimeter wide, another two years and another millimeter of tear, and finally one day it rips completely.

If the problem is a loose body sailing around the synovial sea, it probably started off as a small bone chip that broke loose during a moment of trauma. They range from sand size to as large as a quarter. Of course the body doesn’t like UFO’s (Unidentified Floating Objects), so it tries to break them down and reabsorb them. If that doesn’t work, it tries to wall the intruder off by laying down scar tissue, or it may start laying calcium over it. In either case the end result is felt as a locking sensation or a “giving way” of the knee.


To alleviate true locking, the fragment must be removed, whether it’s a bone chip or a torn meniscus. Otherwise there will be subsequent damage as the fragment continues to wedge itself into the bones of the knee. Fortunately, bothersome pieces of cartilage can easily be removed by a surgical technique called arthroscopy.

Some people have tried rest, elevation, and anti-inflammatories in an attempt to lesson the swelling that sometimes accompanies locking. Occasionally this allows the fragment to slide back into place. Others have also tried twisting or manipulating the leg. However, the best answer is still a surgical one.

Pseudo-locking

The second type, which I call pseudo-locking, is what a lot of people call locking when certain movements simply hurt too much to do. The knee may not be incapable of complete movement, but there is an area of exposed surface within the knee. When that surface bumps up against another surface there is pain and discomfort, which discourages you from extending your knee all the way.

So you tell your doctor your knee is locked and you can’t straighten your leg out all the way. You say, “My knee locked while going down a flight of stairs. There was this sharp pain and then I couldn’t move it.” I say, “But can you move it if you try?” “Yes,” you say, “but it hurts.” What is actually happening is that when your knee hits a particular angle or feels a certain pressure, it hits the panic button, triggering protective muscle function and a string of internal expletives.

The most common cause is damage to the knee surface, generally chondromalacia patella or osteoarthritis. You will likely have a history of grating within the knee if you develop pseudo-locking. You’re also a likely victim of a subluxating or dislocating patella. Swelling, however, is not common.

For pseudo-locking the best treatment is rest, which allows the area of irritation to heal and then regain its movement and strength. So if you suffer from an episode of pseudo-locking, relax. Get off your feet for a few minutes. Usually you’ll be able to move again- gently—after a few minutes. A cold pack while you’re resting may also help.

GIVING WAY

Sometimes a knee doesn’t lock, but it does give way for a moment, giving the owner a bit of a stop. When I was growing up in the Midwest l had an electric train. If it went over an imperfect junction it would bounce off the edge and bump right back onto the track. Like my Lionel train, the knee has three tracks. One holds
the kneecap (or patella). lf, for some reason, the kneecap doesn’t stay in its track and subluxates (slips out) for a moment, your thigh‘ muscles lose control. That’s instability. If one of my Lincoln logs fell across my train track, it would derail. A loose body along the general track of your knee probably won’t derail you, but you’ll know you’ve hit a bump. And the third track is made up of your ligaments. Perhaps they’ve been damaged by injury or become stretched out. The forces of movement may be too much for them to handle and they give way. All of these would come under the general diagnosis of patella subluxation or dislocation.

Another possibility is that the muscles that control the knee are weak and unstable; perhaps there was a previous injury and they have not been properly rehabilitated. If the muscles lose control for a moment, you feel them give way and you instinctively reach for support or prepare for a fall.

Giving way due to an old ligament injury, muscle instability, or the locking of a loose body frequently occurs while descending stairs or jumping from a height. If the problem is a torn cartilage, the triggering event is often a rotary movement, such as turning round suddenly, stepping on a small stone, or walking on uneven
ground.

SNAP, CRACKLE, POP

Perhaps the most common concern expressed about the knee comes from people who worry about the snap, crackle, and pop that comes with activity. They fear that their knees are deteriorating right before their very ears. For the most part, as long as there is no accompanying pain, an occasional grumble from the knee should not be of major concern. In fact, considering what the joint is forced to put up with over the course of daily living, it’s not all that surprising that most people over the age of twenty manage to hear at least some knee noise.

Generally, such sounds can be traced to tiny bits of cartilage that have chipped away from bone and gone floating off into the synovial sea. When the joint moves, the chip passes between the intact cartilage and makes a popping sound. Usually, this is not painful and does not damage the joint. It just makes it tricky to
sneak up on people.

When large pieces of cartilage have broken off, however, they may actually chip away more protective cartilage as they go popping around the knee. And if a large piece wedges itself between the bones, the knee may suddenly lock.

How can you tell if the sounds you hear are just normal Rice Krispies or something more serious? Sometimes it’s difficult. lf you’re concemed about it, see your orthopedic specialist. However, the rule of thumb (or knee) is that you’re safe as long as there is no accompanying pain, swelling, or loss of function. For example, if you can’t sit for a normal length of time without pain, that would indicate a loss of function. (That’s what the British call “the theater sign.”) If you have poorly localized knee pain, which is exacerbated
by going down stairs and hills, that also could indicate a more serious problem. Again, when in doubt, ask a specialist.

Most commonly heard is an occasional click, which is fairly universal and represents nothing very significant. Too many clicks, however, equal a creak, and you don’t want to be up a creek without a diagnosis. So if you’re worried, check in for a checkup.

The most common cause of all this noise is chondromalacia patella, which results from trauma. A subluxating or dislocating patella is also a possibility, with traumatic and degenerative arthritis a less likely competitor in the snap, crackle, pop diagnostic derby.

A snap or pop (which is not accompanied by a traumatic event) could represent something sliding over the joint, such as a torn cartilage or a loose fragment. It could also be the kneecap snapping or popping along (or out of) its track.

Crackling, grating, or grinding is most worrisome. That is called crepitation, and it means that there is a roughness to a surface and you’re hearing bone rubbing against bone or roughened cartilage. That’s a much more ominous sign of degeneration of a joint surface.

PAIN AND TENDERNESS

Pain may be caused by swelling, nerve fibers that have become torn or irritated, or degenerative changes, most often associated with arthritis. If you can accurately locate the site of the pain, it will greatly assist the doctor in making the diagnosis. Of course if you happen to be a procrastinator, it’s best to remember where the pain was felt first. '

The location of the pain, the severity of the pain, and what makes the pain occur all offer clues to the underlying problem. For example, a low-grade aching pain on the front of the knee occurring during hill climbing most likely represents chondromalacia patella. The same pain may also appear in the middle of physical activity and the same patella problem is probably at fault. (For more information concerning this and other specific complaints.)
Such low-grade pain often begins after activity, but if you persist in these activities, the pain becomes sharper and more persistent. lf left untreated, the pain may eventually force you to severely restrict your activity. Besides chondromalacia patella, this type of pain is symptomatic with tendinitis, patellar tendinitis, or stress fractures on the front of the knee and iliotibial band friction syndrome on the outer side of the knee or bursitis on the inner side.

Another classic pain is often quite sharp and associated with a tearing sensation, swelling, and instability, all brought about thanks to a fall or twisting maneuver deep within the knee. Such moves can cause either ligament or meniscal damage. The mode of injury is often an athlete attempting to change direction quickly. lf there is an audible “Pop!” upon injury, the problem is likely to be a torn anterior cruciate ligament. lf the pain occurs on either side of the knee, then the injury is suggestive of a medial (inner) or lateral (outer) ligament or meniscus tear.

PUTTING IT ALL TOGETHER

Let’s take an example and look at what happens to a knee, and to add some drama to the script, let’s say your first response is to ignore the problem. (Sound at all familiar?) Your foot is planted and you make a sudden turn. No big deal, a little swelling perhaps. But a part of your meniscus has tom and it’s caught there between the inner edge of your femur and tibia. You continue to walk on it, trying to force the knee closed with every step. Your knee says,

“This is stupid. If that’s the way you’re going to be, all I can do is pour out more lubricant and at least try to minimize the damage,” and the swelling increases. You’ve still got that fragment wedged in there, and now the meniscus is starting to atrophy because you keep grinding away at it. At the same time the fragment is starting
to wear a groove in the bone surface, setting the stage for an arthritic condition, an inflammation, or effusion of the joint.

Pain is now more diffuse and you can’t put your finger on the source. (Of course by now it’s so tender you probably don’t want to touch it anyway.) The muscles controlling the knee attempt to protect the injury by going into spasm and preventing the normal arc of movement. Unable to move through their natural range, the muscles start to atrophy. So now you’ve got muscle weakness, a locked knee that probably gives way with increasing frequency, swelling of the knee, more pain than you care to think about, you’re startingto scratch and damage the surface of the joint, and somewhere, from deep inside, comes an inclination to call a doctor.

Perhaps half of the pain of a traumatic injury is due to accompanying muscle spasms. In a spasm the muscles surrounding the injured part vigorously contract and hold that position——sometimes for days. While such spasms are intensely painful, they’re actually the body’s way of protecting itself from further injury. Think of it as a built-in splint, immobilizing the damaged part much like a cast
immobilizes a broken leg.

Too often, pain is ignored or blunted with medication. This is an Invitation to reinjury or even greater injury. When it comes to pain, the individual who self-medicates has a fool for a doctor. If pain persists after two days of self-medication, see your doctor.

Ouch! That Hurts: From Symptoms to Diagnogis (part 1)

Of course the obvious question is how do you know if your injury requires medical attention or if it can be brought around with a little verbal exercise and some T.L.C.?

The key is understanding what your knee is trying to tell you. It’s hard to be a conscientious care-giver if you haven’t a clue as to what your charge is saying. With a better understanding of symptoms, you’ll be a much better guardian to your knee and a lot better patient for your doctor.

In 1985 over 650,000 patients underwent arthroscopy for diagnosis and repair of knee injuries, 84,000 patients had ligamentous repairs, and another 75,000 people were fitted with artificial knees. If these figures make you weak in the knees, the good news is that the vast majority of knee injuries do not require surgical intervention.

From the doctor’s perspective, this is good; any time you invade the body, even for a relatively benign procedure, there is the possibility of complications. Unfortunately, the high-tech advancements of the last few years have gotten a lot of attention, and as a result, particularly for the sports-minded, surgery has become the instant panacea for all known knee ills. That’s not a healthy attitude. There is no orthopedic condition that cannot be made worse by surgery. Yet, to most people, the knee is an absolute mystery. Well, we’ve gone through some of the cast of characters. Now it’s time to start reading your knee. The plot thickens.

EFFUSION, or SWELLING

The pressure of local swelling, or effusion, is one of the most common knee symptoms. This is nature’s way of limiting knee activity until healing occurs or the mechanical disability that is causing the swelling is corrected surgically.

To your doctor, swelling occurs when excess fluid accumulates outside of a joint. If the fluid gathers within a joint, the problem is said to be effusion. If you report swelling, 98 percent of the time the problem is caused by effusion. ln other words, “swelling” has both a technical meaning and a layman’s meaning. However, we give up. There’s no point in bucking that kind of a tide. So, in this book we’ll use the term swelling and not effusion.

There are two types of swelling: One is caused by an increase in the production of the knee’s own lubricant, synovial fluid, and the other by blood where it doesn’t belong (hemarthrosis). If the swelling occurs within the first hour of injury, there is probably bleeding into the joint. If it takes longer, the joint is frantically pumping out additional fluid into the synovial lining trying to lubricate an abnor- mality within the knee.

Sudden and Intermediate Swelling

Sudden swelling within an hour or so of the injury is very suggestive of bleeding into the joint and is probably a ligamentous tear (most often of the anterior cmciate ligament) or a fracture. Swelling that occurs anywhere from two to twenty-four hours after an injury is more likely to be a tear of the meniscus, most commonly medial meniscus. If the knee blows up suddenly and then decompresses, that’s no time to relax. lt could mean major ligamentous damage and injuries involving multiple ligaments around the knee. Indeed, you may have just managed to blow out all the major structures in the knee, including the surrounding envelope, which allows fluid to rush out and bleed into the fatty tissue beneath the skin. That’s why it swells and decompresses so fast. Normal swelling can be compared to a dam with a slow leak. But in the case of a pedestrian accident where the knee is struck by a car bumper, major skiing accident, or any high-velocity/high-force injury, it’s more like a dam that breaks and floods the countryside. The best home treatment for swelling is RICE—rest, ice, compression with a light wrap, and elevation. The immediate application of ice (not directly on skin but wrapped in a towel) can limit the extent of tissue damage and shorten healing time considerably. However, with swelling that occurs two to six hours later, ice is not as beneficial.

Chronic Swelling

If swelling is a problem of long-standing, the individual may describe his condition as water on the knee. The most likely cause is a mechanical or internal derangement caused by trauma, such as a meniscal tear, a knee sprain, or a ruptured ligament. (In children’s knees the causes of swelling are likely to be quite different.) Probably the single most important factor in determining the cause of swelling is a careful review of just what the knee was doing at the time in question. Swelling can sneak up on you, in which case it could be related to arthritis, loose bodies knocking around inside the knee, or infection. If the swelling is rapid, trauma, no matter how trivial, is likely to be the cause. Squatting and turning, or simply turning with the knee flexed and the foot planted, can be enough to tear a meniscus.

If ignored, swelling distends the knee, prohibits full range of motion, and muscles may atrophy from non-use. Furthermore, if the effusion is caused by internal bleeding, the blood acts as a destructive irritant. It may be hard to imagine blood inside the body as an irritant—it’s hard to think of air as an initant either until the dentist blows it on a cavity. Iron within the blood especially irritates the lining of the knee and can even become deposited on the joint surfaces.

Sometimes the only way to get rid of this excess fluid is to drain it off by needle aspiration. If the swelling is easily explained by the circumstances of the injury, a needle aspiration for diagnostic purposes may not be necessary. However, sometimes a sample of the fluid does need to be analyzed for infection, the presence of gout, pseudo-gout, or arthritis. If fat droplets are found suspended in the fluid, this suggests that a bone has fractured.

Sometimes anti-inflammatory agents, such as aspirin, are given to decrease the swelling, but it should be remembered that knees don’t just swell for the fun of it. A swollen knee has a serious problem and it’s telling you that it needs medical attention.

Problem	Degree of Swelling (3 is most)	Speed of Onset	Other Symptoms	Method of Injury
Meniscal tear	1-2	2-8 hrs.	Locked Knee Pain Tearing Sensation	Twisting or squatting
Sprains
Grade 1	1	Immediate	Severe pain	Falls
Grade 2	2-3		Instability	Twisting
Grade 3	3			injuries
Chondromalacia patella	1	Slow and insidious	Aching on front of knee Pseudo-locking Instability Pain with flexion	Subluxated patella Repetitive squatting Overweight Blunt trauma
Osteochondritis dissecans	1	Slow and insidious	Pseudo-locking Low-grade aching Weakness Loose bodies	Unknown
Loose body	2	Intermittent	True locking Instability	Sheer fractures Osteochondrifis dissecans
Osteoarthritis	1-2	Slow and insidious	Stiffness Low-grade aching	Old trauma Aging process
Rheumatoid arthritis	2-3	Slow and insidious	Stiffness Loss of movement Low-grade aching	Unknown
Gout and pseudo-gout	2	2-6 hours	Limited movement	Metabolic disease

There Is No Gender Gab

Training and locker rooms were once largely “Men Only,” but not anymore. In fact, while women make up 52 percent of the population, they comprise 60 percent of the nation’s health-club memberships.

Not surprisingly, along with this increase in activity there has been an increase in sports-related injuries suffered by women. The big question causing considerable debate within sports medicine circles has to do with the relative risks women face in sports activities: Are women at more risk of injury than men?

At the present time this is pretty swampy medical ground and  home to some pretty muddy statistics. But what are the sporting facts of life? Well, women do tend to sustain more injuries than men. For example, after reviewing the injuries sustained by male and female basketball teams during two consecutive seasons, researchers from Northwestem University Medical School, Chicago, found that women sustained 60 percent more injuries than the men.

In their paper, which was published in The American Journal of Sports Medicine (10:5, 297-99, 1982), the authors reported that both sexes had similar ankle injury rates (which was the most frequently injured body part), but the women incurred considerably more knee and thigh injuries as well as more sprains, strains, and contusions. Women are at a greater risk, apparently. Now the question is whether or not their added risk of injury is based on inherent differences between the sexes. To answer this question we first need to know what the real differences are that would affect sports performance and if these differences are really to blame for women’s injuries.

We do know that women tend to be more flexible than men, which is good because this can mean fewer muscular difficulties. However, the characteristics of the female body often breed trouble. Women may be predisposed to knee injuries because their wider hips cause their major leg bone, the femur, to turn slightly
inward, putting more pressure on delicate knee joints. This wider pelvis and angling thighbone may lead to a number of problems including a chronic condition known as runner’s knee, in which the kneecap shifts sideways and rubs against nearby cartilage. This extra width at the hips can also cause a stretching of the quadriceps muscles, which leads to tendon and knee pain. Finally, women in general have only 80 percent of the muscle mass that men do, so pound for pound there is less muscle support for the knee.

Are these differences reflected in actual injury rates, like those uncovered by the Northwestern University researchers? Many experts believe that they are, but like everyone else, experts can make perfect sense and still be wrong.

For years we’ve known that among women’s sports, basketball has the highest injury rate. This isn’t terribly surprising, considering that men’s basketball has the highest injury rate among noncollision collegiate sports. However, studies have suggested that female players sustain more injuries, lose more time while they recover, and require surgery more frequently than male basketball players.

When this problem was first recognized, several investigators concluded that women’s knees were not as tight as men’s knees and this added laxity meant a greater predisposition to injury. However, we now know that there is no significant difference between the knee laxity of males and females.

Other researchers thought that the added risk might be due to women’s smaller ligaments or perhaps to those biomechanical differences we mentioned. While these factors haven’t been dismissed, a more likely candidate for blame has been found: inadequate conditioning.

How conditioning (or lack thereof) takes its toll is best explained by a study comparing injuries sustained by two Oklahoma City varsity basketball teams (The Physician and Sportsmedicine, 6:10, 92-95, 1978). While the boys’ team showed a consistent rate of injury throughout the season, the members of the girls’ team were
about six times as likely to be injured in the first three months of the season compared to the last two months of play, when their injury rate was nearly identical to the boys’ team. This suggests that the girls were in poorer condition at the start of the season, so they were injured frequently until they were conditioned and more experienced.

A study released just as this book was going into production confirms the importance of conditioning and adds another element for injury prevention. The National Athletic Trainers’ Association (NATA) in June of 1987 reported the results of the first nationwide survey of injuries among girls who play high school basketball. They found that Z3 percent of the more than 400,000 girls playing the game were sidelined at least once during the preceding school year. Their recommendations for curbing the injury rate: Improve
physical conditioning programs and institute a five-minute warm-up period after halftime. The latter suggestion was based on the fact that fully 60 percent of all game-related injuries occurred during the
second half of the play. Many of these injuries could be prevented, according to NATA, by simple stretching and flexibility exercises prior to the start of the second half.

So in reviewing the available literature (which is none too extensive), women may be inherently more susceptible than men to muscular injuries due to a difference in muscle mass. And, due to their overall alignment, iwomen may be at greater risk of knee problems in general. On the other hand, women may not be as likely to sustain a ligamentous injury. However, most of the injury rate difference between men and women in sports could be erased with improved strengthening and conditioning programs for women. There may be other factors influencing women’s injury rates in sports, but it may be a while before these are revealed. The problem is that we’ re not sure yet how much of what we’re learning is true and how much is statistical aberration.

If you’re concemed about being injured in your chosen sporting endeavors, whether you’re a pro or a rank (or unranked) amateur, you largely create your own risk of injury by choosing how prepared you are for action. Want to avoid injury? A good place to start would be to incorporate the protective stretching and conditioning exercises at the end of this book into your activity schedule.

Here’s some encouraging news: in the November 1984 issue of The Joumal of Musculoskeletal Medicine, when highly trained athletes are compared, there is no difference in injury rates between the sexes. This means that as opportunities open up and better conditioning and training programs are initiated for women, the rate of injury to women should continue to decline.

On Your Knees

Once the knee was considered little more than a basic hinge; like a garden gate, it swung open and closed. This reductionist view was eagerly embraced by the medical profession, which had enough problems to contend with without worrying about a joint that seemed to be simplicity in motion. However, it offered little comfort to patients who were in agonizing pain.

Today we recognize that the knee doesn’t just flex; it also glides, Q slides, twists, rocks, and rolls. The demands placed upon the modern knee would be a challenge to the best-designed machine, but the knee is the most poorly constructed joint in the body, with little intrinsic stability. Cons quently, almost everything people do for recreation is tough on the knee. In fact, much of what the knee faces in simple day-to-day living—kneeling, walking, climbing, and being crossed while at rest—can take a toll over time.

At its most fundamental, the knee is indeed a hinge that connects the thighbone (femur) and the leg bone (tibia). While seated, the bones barely touch, but stand up and they lock together, providing a strong, unified structure.

Holding these two bones together are four major ligaments: the two collateral ligaments, which run up the inside and outside of the leg, and the two cruciate (as in “excruciating pain”) ligaments, which cross within the joint. The former provide side-to-side stability, while the latter prevent the bones from slipping backward or forward out of the joint. No matter how powerful the muscles around the knee, without most of its strong, resilient ligaments, the joint would be useless.

The anterior (front-to-back) cruciate ligament (ACL) is often torn in contact sports or sprained during activity. Like its partner, the posterior (back-to-front) cruciate ligament (PCL), it should look like a good strong rope. However, when it’s tom completely, it becomes a frayed mass swaying in the currents. Some athletes can get by without it, others need as knee brace or surgery.

The primary problem with ligaments is that they are tough but not particularly ?exible. Once, stretched, a ligament tends to stay stretched, and it stretched beyond 6 percent of its length, it snaps, leaving the knee vulnerable to further injury. 

If an audible “pop” is noted upon injury, the odds are that the ACL has been damaged. A classic ACL rupture involves an athlete who is running and trying to change directions quickly. He plants his left foot and cuts over it with his right, thus screwing the left leg as he rotates his body until he feels excruciating pain and hears the knee pop. In this situation the athlete generally hits the ground before the ball does.

In basketball the player may be coming down from a jump when he or she is thrown off balance by landing on someone’s foot. The femur externally rotates and extends as he or she tries to prevent falling, causing an ACL rupture.

Bones are soft enough to wear away with the least bit of rubbing, so to alleviate bone-on-bone wear and tear nature covers the ends of the most active bones with a natural shock absorber called cartilage. There are no blood vessels or nerves in this white, gristle-like substance and, to keep this cartilage from just wearing away, the whole area is enclosed in a sac containing a thick fluid substance that looks like the white of an egg. This synovial fluid further protects and lubricates the joint. The sac itself is known as the bursa, and when irritated over time, the end result is called bursitis.

The cartilage between the bones in the knee is called the menisci. What is commonly called a torn cartilage is more accurately a tear of one of the menisci of the knee joint. The menisci are two thin, crescent-shaped structures that fact as shock absorbers between the thigh and leg bones. By pushing synovial fluid around, they also contribute to the lubrication of the knee and to the nourishment of the cartilage. A child’s ability to jump for joy, a professional athlete’s career, and an elderly person’s general mobility all largely depend on the way the cartilage crumbles.

There are two basic types of meniscal tears: acute tears and degenerative tears. Originally, orthopedic surgeons felt that any tom meniscus must be totally removed. Indeed, during the sixties and seventies meniscectomy was the most common orthopedic surgical procedure. Now we realize that he who hesitates is saved. Looking back on all those meniscectomies, we discovered that people who have a torn meniscus removed in their twenties have a greatly increased risk of developing arthritis by the time they’re forty-five or fifty. In fact, studies have found evidence of degenerative changes within the knee in up to 85 percent of meniscectomy patients at a ten-year follow-up. What this means for all those athletes who had meniscectomies during the 1950s, 1960s, and early 1970s remains to be seen. Unfortunately, the feeling in the sports medicine community is that, due to those meniscectomies, the number of former athletes who will need total knee replacement will increase steadily during the next couple of decades.

This is because without the meniscus acting as a buffer, the two joint bones rub against each other. In time the bones can wear away at the ends, leaving nerves painfully exposed. The result is osteoarthritis, or degenerative arthritis, which can spread to the entire joint.

Researchers estimate that the medial meniscus and anterior cruciate ligament absorb 90 percent of all knee injuries. Once they were a primary cause of lifelong limps. Today if the injured is lucky and the injury is accurately diagnosed, he or she will be left with little more than a dot of a scar and an heroic tale of medical trauma to entertain the masses or at least the folks at the next cocktail party.

The mode of injury for the meniscus is similar to that of the ACL. Often they are injured together and that can confuse all concerned. If one problem and not the other is corrected, the knee is still damaged and very susceptible to reinjury.

Moving on, the front shield of the knee is the ever-popular kneecap or patella. When you knee a piece of furniture or open a door without getting out of the way, it is the kneecap that lets you know you’ve made a mistake. The patella moves within a track near the end of the thighbone. A severe sudden twist or constant stress can throw the kneecap off track. Although it takes some powerful abuse, when it is seriously injured it can take much of the future with it.

That’s because the kneecap is the fulcrum that gives power to the muscles of the leg. It also absorbs a lot of the stress of daily activities, like climbing stairs. You don’t realize it, but when you simply walk up a few stairs the pressures across your knees are approximately four times your body weight! This massive load is largely due to forces that are generated by muscles being worked. Furthermore, damage to any major muscle in the leg will mean more work for the patella and could begin to wear it clown.

The major muscles and bones of the knee and legs

Tying all this together is a thick and powerful system of muscles and tendons that flex, drive, and support the knee. The front thigh (quadriceps), hamstring, and calf muscles are the three major muscle groups involved and the only supporting structures that can be strengthened. The patella tendon connects the kneecap to the front thigh muscle and shinbone. A tear here is called “jumper’s knee” and is common among basketball and volleyball players, hurdlers, and male dancers.

Injury to any of these structures, which provide stability at the knee joint, represents a major cause of disability, loss of playing time, and the beginning of the t degenerative arthritic changes that may befall an active individual.

If all of this makes you feel like wearing designer armor the next time you’re heading out for a little recreation, do remember that probably 70 percent of all knee injuries are of a relatively minor nature. And you’ll be much better equipped to both prevent and pinpoint your own knee problems now that you know what’s where!