Thursday, November 8, 2007

Knee Pain: Risk Factors

RISK FACTORS
(content provided by MayoClinic.com)
Weighing more than your ideal weight is one of the leading risk factors for knee pain. Excess weight increases stress on your knee joints, even during ordinary activities such as walking or going up and down stairs. It also puts you at increased risk of osteoarthritis by accelerating the breakdown of joint cartilage.

Other factors that make you more susceptible to knee pain include:

  • Overuse. Any repetitive activity, from cycling a few miles every morning to gardening all weekend, can fatigue the muscles around your joints and lead to excessive loading stress. This causes an inflammatory response that damages tissue. If you don't allow your body time to recover, the cycle of inflammation and microdamage continues, putting you at increased risk of injury. It's not repeated motion itself that's to blame, but rather the lack of adequate recovery time. That's why current strength training guidelines advise against working the same muscle group on consecutive days, for example.
  • Lack of muscle flexibility or strength. According to experts, lack of strength and flexibility are among the leading causes of knee injuries. Tight or weak muscles offer less support for your knee because they don't absorb enough of the stress exerted on your knee joints.
  • Mechanical problems. Certain structural abnormalities, such as having one leg shorter than the other, misaligned knees and even flat feet, can make you more prone to knee problems.
  • High-risk sports and activities. Some sports and activities put greater stress on your knees than others. Alpine skiing with its sharp twists and turns and potential for falls, basketball's jumps and pivots, and the repeated pounding your knees take when you run or jog all increase your risk of injury.
  • Previous injury. Having a previous knee injury makes it more likely that you'll injure your knee again.
  • Age. Certain types of knee problems are more common in young people — Osgood-Schlatter disease and patellar tendinitis, for example. Others, such as osteoarthritis, gout and pseudogout, tend to affect older adults.
  • Sex. For reasons that aren't entirely clear, your sex may increase your risk of some types of knee injuries. Women are more prone to ACL tears than men are, and teenage girls are more likely than boys to experience a dislocated kneecap. Boys, on the other hand, are at greater risk of Osgood-Schlatter disease and patellar tendinitis than girls are.

Sunday, November 4, 2007

Knee Problems

I have heard many a line dancer complain of aches and pain in their knees; some to the extent of having to stop pursuing their favourite pastime. Knee problems are not confined only to line dancers. As we age, our 'engine' and 'parts' will eventually show its wear and tear, especially if we haven't been very good at taking care of our body.

If you type the words 'Knee Problems' into Google Search, a host of websites dedicated to this subject is listed. I have tried my personal best to summarise what I've learnt from these sites and hope the information will enhance your own knowledge of the subject.

Knee pain is a common reason that people visit their doctors' offices or the emergency room. Often, knee pain is the result of an injury, such as a ruptured ligament or torn cartilage. But some medical conditions can also bring you to your knees, including arthritis, gout and infections.

Depending on the type and severity of damage, knee pain can be a minor annoyance, causing an occasional twinge when you kneel down or exercise strenuously. Or knee pain can lead to severe discomfort and disability.

Many relatively minor instances of knee pain respond well to self-care measures. More serious injuries, such as a ruptured ligament or tendon, may require surgical repair.

Although every knee problem can't be prevented — especially if you're active — you can take certain steps to reduce the risk of injury or disease. (extract from Mayo Clinic)

Our knee is a complex mechanism consisting of several parts:

  • The 4 bones (i.e the femur, tibia, fibula & patella)
  • Ligaments
  • Tendons. These fibrous bands of tissue connect muscles to bones. Your knee has two important tendons, which make it possible for you to straighten or extend your leg: the quadriceps tendon, which connects the long quadriceps muscle on the front of your thigh to the patella, and the patellar tendon, which connects the patella to the tibia.
  • Meniscus. This C-shaped cartilage, which curves around the inside and outside of your knee, cushions your knee joint.
  • Bursae. A number of these fluid-filled sacs surround your knee. They help cushion your knee joint so that ligaments and tendons slide across it smoothly

When any of these parts fail to work together smoothly...due to injury or disease...decreased function, muscle weakness and pain is the result.


CAUSES

There are many causes of injuries to the knee. In a line dancer, it would mostly like be due to the following:

  • failure to warm up and stretch before exercise
  • improper alignment during turns
  • inappropriate and/or ill-fitting footwear
  • inappropriate dance floor/surface

Another cause leading to weakened knees, opening them up to the possibility of injuries, is largely physiological. As Asian women, we typically do not consume enough calcium-rich food. As such, it is highly likely that we had built up insufficient stores of calcium during our adolescence and youth. When age catches up and menopause sets in, we are quickly depleted of our stores. The result is inevitable...
OSTEOPOROSIS and/or OSTEOARTHRITIS.


Common knee injuries: the hows & symptoms:

Ligament injuries
How:

  • Injury from sports or activities requiring quick stops and turns
  • Contact sports causing repeated blows to the inside or outside of the knee.
  • Damaged by repeated stress, causing them to lose their elasticity, much like an overstretched rubber band.

Symptoms:

  • Tear of the Collateral Ligaments - immediate pain in the injured area. The discomfort, which can range from mild to severe, is usually worse when you walk or bend your knee. If the collateral ligament on the inside of your knee sprains or tears, you may feel a ripping sensation. In some cases, this ligament may become calcified after repeated injuries (Pellegrini-Stieda syndrome).
  • Tear of the ACL (Anterior Cruciate Ligament) - may feel or hear a pop in your knee, intense pain and immediate swelling. Knee may "buckle" or at least feel as if it might give way when you try to stand or put weight on it. In most cases, you'll have to stop all activity, either because the pain is too severe or because your knee isn't stable enough to support your weight.
  • Tear of the PCL (Posterior Cruciate Ligament) -not as dramatic or painful. Most often, you'll experience pain and swelling in the space behind your knee (popliteal fossa) and a feeling of instability, as if your knee might give way.


Tendon injuries
How:

  • Inflammation of the quadriceps tendon (tendinitis) can occur in people who run, bicycle or ski.
  • Can also result from inflammatory diseases that occur throughout your body, most notably rheumatoid arthritis.
  • Middle-aged weekend fitness buffs are more likely to rupture their quadriceps tendon than seasoned athletes.
  • Patellar tendon ruptures frequently occur in active younger people who have a history of tendinitis or who have had steroid injections in their knees.

Symptoms:

  • irritation and inflammation of one or more tendons — the thick, fibrous cords that attach muscles to bone.
  • pain and swelling at the front of the knee and just below the kneecap. The discomfort usually isn't constant but tends to occur when you jump, run, squat or climb stairs.
  • If the quadriceps or patellar tendons rupture, either partially or completely, the pain is likely to be most intense when you try to extend your knee. If the tendon is completely ruptured, you won't be able to extend or straighten your knee at all.

Meniscus injuries
How:

  • As a result of aggressive pivoting or sudden turns.
  • Any activity that twists or rotates your knee.
  • Occasionally, you can tear your meniscus while lifting something heavy.
  • Older adults sometimes tear their meniscus during repetitive movements, such as kneeling or squatting.
  • Weakened due to degeneration over time.

Symptoms:

  • pain and mild to moderate swelling that develops over 24 to 48 hours
  • interference with knee movement
  • causing knee joint to lock so that leg can't be straightened completely


Bursitis
Inflammation in the bursae, the small sacs of fluid that cushion the outside of your knee joint so that tendons and ligaments glide smoothly over the joint.
How:

  • Occurs after an activity that requires you to kneel for long periods — scrubbing floors, gardening, or installing tile or carpet, (aka housemaid's knee/carpet layer's knee).
  • Can also result from an infection
  • One of the signs of arthritis or gout.

Symptoms:

  • warmth, swelling and redness over the inflamed area
  • aching or stiffness while walking
  • considerable pain when kneeling
  • pain going up or down stairs.
  • if infected can lead to fever, pain and swelling


Dislocated kneecap
Triangular bone that covers the front of your knee (patella) slips out of place.

How:

  • Contact sports and activities that require a change direction while running, such as tennis, racquetball and volleyball.
  • If your knees tend to turn inward or your kneecaps are higher than normal, you may be more prone to this injury.

Symptoms:

  • dislocation is noticeable
  • kneecap is likely to move excessively from side to side
  • intense pain and swelling in the affected area
  • difficulty walking or straightening your knee

Osgood-Schlatter disease
This condition can develop in athletic young people during the years when their bones are growing rapidly — usually ages 10 to 15 for boys and 8 to 13 for girls. Osgood-Schlatter disease results from repeated tugging of the patellar tendon on a growth plate at the top of the tibia. This is most likely to occur during activities that involve running, jumping and bending, when the pull of the quadriceps muscle puts tension on the patellar tendon. In time, the tendon may begin to pull away from the tibia, resulting in a small bump you can see. In severe cases, the tendon may come away from the tibia completely.

Symptoms:
  • pain, swelling and tenderness at the bony prominence (tibial tuberosity) just below the kneecap
  • the pain is usually worse with activity, especially running and jumping, and improves with rest
  • frequently affects just one knee, but sometimes develops in both knees
  • discomfort can last from weeks to months and may continue to recur until the child stops growing.

Hyperextended knee
How:
  • This usually results from an awkward landing after a jump or from a contact injury.
Symptoms:
  • pain and swelling

Iliotibial band syndrome
This occurs when the ligament that extends from the outside of your pelvic bone to the outside of your tibia (iliotibial band) becomes so tight that it rubs against the outer portion of your femur.

How:
  • You're more likely to develop iliotibial band syndrome if you have biomechanical problems such as unequal leg length or weak hip abductors, the muscles responsible for sideways leg motion.
  • Exercising on concrete surfaces or uneven ground
  • Increasing the intensity or duration of your exercise too quickly
  • Wearing worn, inappropriate or ill-fitting shoes
  • Excessive uphill or downhill running

Symptoms:

  • sharp, burning pain in the knee
  • initially, the pain goes away with rest, but in time it may persist when you walk or go up and down stairs.


Loose body
Sometimes injury or degeneration of bone or cartilage can cause a piece of bone or cartilage to break off and float in the joint space. This may not create any problem unless the loose body interferes with knee joint movement — the effect is something like a pencil caught in a door hinge — leading to pain and a locked joint.


Septic arthritis

Sometimes your knee joint can become infected, leading to swelling, pain and redness. Septic arthritis often occurs with a fever.



The above are just some of the reasons for acute knee pain. There's also chronic knee pain (eg. Rheumatoid Arthritis, Osteoarthritis, Gout & Chondromalacia of the patella), but we will not delve into these in this post.

In my next post, I will be summarising the information gleaned from the Internet: RISK FACTORS leading to certain people being more prone to knee injuries and pain than others.