Overview To judge by the number of professions and activities that have
knee complaints named after them - housemaid's knee, runner's knee,
clergyman's knee - this large weight-bearing joint can be a pain. (Note
for trivia buffs: Latin for knee is genu, hence the verb to
genuflect or bend the knees as in worship or prayer). Although the
knee has the range of motion of a rotating hinge, it can also lock into a rigid structure, allowing
us to form a straight leg.
This ability to walk upright (bipedalism) led to a dramatic shift
of gravitational forces and extra loading on the knee. Even simple,
everyday activities like walking downstairs and gardening (gardener's
knee?) can be a potential source of injury. During high intensity
athletic activity - like lifting weights from a bent position - the load
can reach six times the body weight. And in fast motion sports
like football, where sudden changes of direction are common, the
rotational forces may be more than a knee can bear.
Injuries Because the knee is so often jarred during running and jumping
movements, the cartilage and menisci are very prone to wear and tear.
Tendons are also susceptible to repetitive motion injuries. With
overuse, they can stretch and become inflamed (tendinitis).
The ligaments of the knee are possibly the most under-reinforced
elements of the body. These structures, particularly the anterior
cruciate ligament (ACL) are frequently injured during sports
activities. Twisting motions, in which the upper leg rotates while
the lower leg is fixed or planted, can result in torn ligaments.
Recurring microtrauma. These small but cumulative injuries can cause serious damage to
the knee.
Tackles in football, impacts against hard surfaces,
minor twists from skiing, all add up to larger problems over
time.
Poor technique. Whether walking, standing, bending, or
weightlifting, unnatural movements of the knee can cause wear
problems on the joint.
Over-work. Some people are more prone to degenerative
conditions that wear away cartilage and other protective
structures.
Good Practices
Keep strong. Well-developed and conditioned muscles ease
stress on the joint, help the knee cap track properly, and add protective
mass.
Keep flexible. Good flexibility in the knee allows ligaments
to move without tearing or rupturing.
Don't over-extend. Work within your limits and listen to those sounds and sensations in
the knee. Often, they're just the harmless movement of tendons
over bones, but repeated snaps, pops, or grinding sensations may
mean harm is being done. And persistent pain is usually a
reliable indicator that the knee is injured.
General Conditioning More so than most joints in the body, the condition of the knee is
affected by the surrounding muscles and ligaments. A strong and
long-lasting knee is usually the result of thorough conditioning and
physical activity; the best routines will target the entire region of
the knee, including the front quadriceps, the rear hamstrings, and
the calf muscles in the lower leg.
Training and exercise routines should recognize some of the
inherent weaknesses of the knee. The intensity or duration of
training should increase gradually, building-up by no more than 10%
per week. Activities or exercises that place extreme pressure on the
underside of the kneecap (deep knee bends for example) should be
carefully employed. Appropriate shoes that help stabilize and cushion
the knee, proper stretching and warm-up routines are easy ways to
reduce injuries while exercising.
Anatomy
The basic problem with the knee is this: how to sit the femur (or thigh) bone on top of the tibia (shinbone), maintain flexibility, yet create stability and endurance. It's a bit like trying to balance one chopstick on top of another. Obviously, you need some kind of cushion between the chopsticks, and strings or tapes to bind them together. This is essentially what Mother Nature has created. Between the femur and tibia are two pads of shock-absorbing tissue called menisci (plural of meniscus), which protect the surfaces and add stability and shock absorption. The ends of the bones are covered with a smooth, resilient surface called articular cartilage that allows for fluid movement. Strong vertical bands of elastic tissue called ligaments lash the bones together. The final touch is the patella (or kneecap).
On the front of the femur, there is a slight groove (the patellofemoral groove) that guides the movement of the kneecap. The kneecap is not only positioned by this groove, but also by the surrounding quadriceps muscles, and the patellar and quadriceps tendons. As the quadriceps contract, they pull the attached tendon, sliding the kneecap, and extending the lower leg. Fluid filled sacs (bursae) decrease the friction between two surfaces that move in relationship to one another, such as bones, tendons and muscles.
The Body in Motion
How Badly are You Hurt? Get answers to triage questions that will help you decide whether to contact a doctor.
Product Considerations
Knee: Compression Sleeves Knee compression sleeves give added support, increasing stability and helping to reduce swelling in an injured knee. Patients that have light sprains may be directed to use a compression sleeve during the early stages of rehabilitation. Other patients that have ongoing knee problems or chronic conditions may be recommended to use a sleeve on a daily basis. These sleeves are less restricting than most other knee supports and can be worn under loose fitting clothing.
Knee compression sleeves can be used to treat:
Light swelling.
Light knee strains.
Chronic inflammation.
Degenerative joint disease.
Arthroscopic Surgery Few advances in surgical techniques have been as beneficial as the development of arthroscopic surgery. An arthroscopic procedure greatly reduces...
