Understanding How Your Knee Works
Author: James Hughes

The knee is a lower extremity joint connecting the femur and
the tibia. Because the knee is responsible for supporting
almost the entire weight of the human body, the knee is
especially vulnerable to injury and to the development of
osteoarthritis.

The knee is a very complex joint, made up of bone, cartilage
and tendons. The knee is actually made up of two separate
joints. The femoro-patellar joint consists of the "kneecap" or
patella, which sits inside the anterior thigh muscles tendons,
and the patellar groove on the front of the femur bone through
which it slides. The femoro-tibial joint connects the thigh
bone, known as the femur, with the tibia, the large bone in the
lower leg. One unique feature of the knee is that the joint is
surrounded with a thick fluid found inside a membrane.

The knee also contains the following ligaments, which most
sports fans could probably list off verbatim considering the
high number of incidents of highly paid professional athletes
tearing one or more of them.

The anterior cruciate ligament (ACL). The ACL is probably the
best known of the knee ligaments and is extremely important in
good knee health. The ACL keeps the tibia bone from being moved
too far to the front of the knee in relative position to the
femur bone. The ACL is one of four major ligaments inside the
knee. It connects from the back and outside part of the femur
bone to the front and inside part of the tibia bone.

The posterior cruciate ligament (PCL). Not to be confused with
the Pacific Coast League of minor league baseball, the
posterior cruciate ligament is the second of the four major
ligaments in the knee. It connects the back intercondylar area
of the tibia bone to the medial condyle of the femur. An exam
called the posterior drawer test is used by doctors to detect
injury to the PCL. During the test, the doctor will position
himself sitting on the end of the patients foot with the knee
turned 80 degrees. The doctor then jerks the tibia backwards.
If there is excessive movement, a tear in the PCL is probable.

The Capsular Ligament. Also known as the joint capsules or
articular capsules form a space for the bone joints to move in.
Each capsule is made up of two layers – an outer layer made up
of white, fibrous tissue, and an inner layer which secretes
fluid.

The Ligamentum Patellae. The Patellar ligament is an anterior
ligament and is a strong and flat band about 8 cm long and is
attached to the kneecap and to the tibia. Its fibres stretch
over the front of the kneecap with the tendon from the
quadriceps.

The Medial Collateral Ligament. The MCL protects the side of
the knee from being bent open from a force from the other side
of the knee.

The Lateral Collateral Ligament. The LCL protects the knee from
a bending force from inside the knee.

The Oblique Popliteal Ligament. The OBL is a broad, flat,
fibrous band.

As you can see with all these different aspects to the knee
there is a high possibility of things going wrong within the
joint.


About The Author: James Hughes has an interest in Knee Pain.
For further information on Knee Pain please visit
http://www.banishkneepain.com/kneepain.html or
http://www.banishkneepain.com/blog/2006/10/10/understanding-how-your-knee-works/