Knee Joint

Synonyms

Articulatio genus, knee, femoral condyle, tibial head, joint, femur, tibia, fibula, patella, meniscus, cruciate ligaments, anterior cruciate ligament, posterior cruciate ligament, collateral ligaments, inner ligament, outer ligament

  • Thigh muscles (Musculsus quadriceps femoris)
  • Thigh bone (femur)
  • Thigh tendon (quadriceps tendon)
  • Kneecap (patella)
  • Patellar tendon (patella tendon)
  • Patellar tendon insertion (Tuberositas tibiae)
  • Shinbone (Tibia)
  • Fibula (fibula)

Anatomy

The knee joint is the largest and most stressed joint in the human body. Accordingly, the knee is also the most frequently injured joint. The knee joint is a so-called hinge joint.

This means that the knee joint can be both bent and rotated. The knee joint is made up of three bones, the femur, the tibia and the patella. The fibula is not involved in the knee joint.

The knee joint is divided into two lower joints: The femur – tibia – jointThe joint is formed by the femur with its two joint heads (medial and lateral femoral condyles) and the tibial plateau (tibial plateau). The round femoral heads lie in the small hollows of the tibial plateau (fossa intercondylaris). The ratio of the joint surface of thigh to tibia is about 3:1.

Since there is only a punctiform contact between thigh and tibia, the knee joint flexes with a rolling sliding movement.

  • The femoral- tibial joint (femorotibial joint)
  • The tibia – patella joint (femoropatellar joint)

The thighkneecap – jointThe kneecap slides during bending through a predetermined slide path between the heads of the femur bone (femoral condyles). In total, the patella can thus slide between 5 – 10 cm.

In order to cover this distance, larger sliding layers are necessary. Two bursa sacs (bursa praepatellaris and bursa infrapatellaris) form two large sliding gaps for this purpose. The large thigh muscles (Musculus quadrices femoris) attach to the kneecap (patella) from above.

The force of these muscles is diverted via the patella to the lower leg. The patellar tendon (patellar tendon) attaches to the lower patella pole, pulling towards the front edge of the tibia and connecting to the tibia at a bony protrusion (apophysis = tuberosity tibiae). To stabilize the femur in the small socket of the tibia (Fossa intercondylaris), there are various knee stabilizers: The cruciate ligaments prevent the femoral heads from sliding forward (anterior cruciate ligament) or backward (posterior cruciate ligament) relative to the tibia.

They are the decisive stabilizers of the knee joint. The collateral ligaments stabilize in a lateral direction to prevent the knee joint from buckling into a bow-leg or knock-kneed position. The inner ligament is firmly attached to the inner meniscus, so the inner meniscus is more immobile than the outer meniscus.

The joint capsule of the knee joint is strongly tensed and stabilized at full extension. With increasing flexion, it slackens and the remaining stabilizers have to take over the tasks.

  • The meniscus (inner and outer meniscus)
  • The cruciate ligaments (front cruciate ligament, rear cruciate ligament)
  • The side bands (inner band, outer band)
  • The joint capsule
  • Thigh bone (femur)
  • Inner meniscus
  • Anterior cruciate ligament (VKB)
  • Shinbone (Tibia)
  • Outdoor Meniscus