Is your knee a joint

Answer 1

They work the same as our joints.

Answer 2

Humans may have evolved by being able to augment their diet with the concentrated form of protein derived from eating other animals. To obtain protein from this source was difficult as animals typically run faster, jump higher, and some are meat-eating themselves and thusly better approached from a distance. To successfully accomplish the hunt for food, the human species developed two significant physical traits, the opposablethumb for grasping and the LOCKABLE knee joint for supporting powerful and aggressive throwing.

The knee locks in extension when the lower leg is internally rotated by the contraction of the SARTORIUS muscle. Further contraction of the surrounding thigh muscles, RECTUS FEMORIS, ILIOTIBIAL BAND, along with the BICEPS FEMORIS, all serve to firmly pull the lower leg proximally into the closed and locked position, ready now to support the entire body needed for standing, running, or throwing (spears, baseballs, or whatever).

To reverse the above process of unlocking, the knee must be first unweighted by shifting the body weight to the opposite leg - then the lower leg is externally rotated by the contraction of the POPLITEUS muscle followed by full knee flexion by contraction of the BICEPS FEMORIS muscle pair. All of this activity happens automatically even though these muscles are under voluntary control.

The overall twist (internal/external rotation) of the lower leg (tibia) on the upper leg (femur) is approximately 5 degrees.

The medial and lateral menisci serve to guide and center the femoral and tibial articular surfaces and often contribute to inadvertant LOCKING when they are defective (torn or folded) or misplaced due to swelling. An uncomplicated (no fracture, degenerative Arthritis, ripped or torn ACL/PCL/collateral ligament, or joint mice) and locked knee joint is a frightening experience, to be sure, however, the knee is easily unlocked (with assistance, typically) by pressing deeply with both thumbs just below the knee cap and slightly to the outside of the patellar ligament. Pressing firmly there as the knee is slowly and gently extended will release the meniscus. The lower leg will actually be felt to 'thunk' free and the individual will be able to immediately stand and use the leg normally although locking may occur again.

Answer 3

Your knee joint is one of the miracles in the nature! It is synovial joint. So you have synovial sheath and fluid to to give mobility and lubrication to the joint. This is hinge type of joint. So your joint can move along with one particular axis. So it does not have ligaments in the front side or the back side. It has got one ligament each on medial and lateral side. That allows for flexion and extension of the joint. Then you have two very beautiful ligaments, that are placed "inside" the joint. Both cross to each other. Both go from femur to tibia bones. They are called as cruciate ligaments. They prevent forward and backward dislocation of the tibia on femur. One of them prevents hyper extension of the knee joint. Then you have two condyles on femur and two condyles on the tibia bone. The condyles on the femur are convex. The condyles on the tibia are concave. That gives very good articulation to the joint. Then you have two plates of cartilages in between the condyles of femur and tibia bones. You have medial meniscus and lateral meniscus. They give lot of added advantage to the smooth movements of the joint. All these advantages allow you to bear the heavy weight of your body for life long time.

Answer 4

Screw home mechanism of the knee during standing:

During extension, the anterior cruciate ligament, (ACL), acts to resist hyperextension and becomes taught.

As the knee approaches full extension, the posterior cruciate ligament, (PCL), also becomes taught, resisting the anterior movement of the femur on the tibia.

The anterior movement of the femur on the tibia is additionally blocked by the anterior horn of the medial meniscus, (which has reached its maximally anterior position).

Further quadriceps contraction produces a medial rotation of the femur on the tibia, (this occurs because the medial femoral condyle is "longer" than the lateral femoral condyle). This femoral rotation into full extension is the "screw home".

Eventually, femoral movement ceases when the ACl and the Collateral Ligaments of the knee have become taught, resulting in a position of slight hyperextension, known as the "locked out knee".

Answer 5

The knee joint makes it possible to bend your legs and walk

Answer 6

I dont know! Do i look like a scientist?

Answer 7

Absolutely, the knee is a joint.