knee

Examples of knee in the following topics:

• Patella (The Knee)

  • The patella (knee cap) is the bone between the fibula and femur.
  • The patella or knee cap is the bone between the fibula and femur.
  • Each leg has a patella to protect its knee joint.

• Knee Injuries

  • Twisting of the knee is a common cause of over-stretching or tearing the ACL.
  • There are two menisci in the knee: the medial (inner) and the lateral (outer).
  • Meniscus tears occur during sports often when the knee is twisted.
  • Sometimes the knee will lock while bending.
  • In the knee the quadriceps and patellar tendon can sometimes tear.

• Muscles that Cause Movement at the Knee Joint

  • The knee joint allows for movement of the lower leg relative to the thigh across the knee joint.
  • The knee joint is in fact comprised of two joints: the tibiofemoral joint between the femur and tibia, which is the weight-bearing knee joint, and the patellofemoral joint, which joins the patella (kneecap) with the femur.
  • The patella additionally protects the knee joint from damage.
  • Actions: Extends the lower leg at the knee joint and stabilizes the patella.
  • Popliteus - The popliteus is located behind the knee joint and acts to “unlock” the knee by rotating the femur on the tibia allowing for the lower leg to be flexed.

• Patellofemoral Stress Syndrome

  • Secondary causes of PF Syndrome are fractures, internal knee derangement, osteoarthritis of the knee, and bony tumors in or around the knee.
  • Specific populations at high risk of primary PF Syndrome include runners, basketball players, young athletes, and females; especially those who have an increased angle of genu valgus (commonly referred to as "knock-knees").
  • Typically, patients will complain of localized anterior knee pain which is exacerbated by sports, walking, sitting for a long time, or stair climbing.
  • For this reason, knee activity should be reduced until the pain is resolved.
  • In addition to physical therapy, external devices such as braces and tape could be used to stabilize the knee.

• Femur (The Thigh)

  • The femur articulates proximally with the acetabulum of the pelvis to form the hip joint, and distally with the tibia and patella to form the knee joint.
  • The shaft descends in a slightly medial direction that is designed to bring the knees closer to the body’s center of gravity, increasing stability.
  • Due to the widening of the female pelvis this angle is greater in women and can lead to increased knee instability.
  • Between the two condyles lies the intercondylar fossa, a depression in which key knee ligaments attach; this significantly strengthens the knee joint and protects it against torsional damage.
  • Finally, the two epicondyles, the medial and lateral, lie immediately proximal to the condyles; they are also regions where key internal knee ligaments attach.

• Bursae and Tendon Sheaths

  • Bursae are found around most major joints of the body, such as the shoulder and the knee.
  • For example, to protect the knee and reduce friction from the various muscles, tendons, and ligaments that attach to and cross the knee joint, knees are cushioned by 14 different bursae: five in front, four laterally, and five medially.

• Common Joint Injuries

  • Common joint injuries include shoulder injuries, elbow injuries, and knee injuries.
  • Physical fitness is related integrally to the development of knee problems.
  • The anterior cruciate ligament (ACL) is the most commonly injured ligament of the knee.
  • Twisting of the knee is a common cause of over-stretching or tearing the ACL.
  • Besides swelling and pain, walking may be painful and the knee will feel unstable.

• Veins of the Lower Limbs

  • The posterior and anterior tibial veins return blood from the calf, ankle, and foot and merge into the popliteal vein behind the knee.
  • The popliteal vein then carries blood from the knee joint up through the thigh.
  • The popliteal vein, shown here in blue, extends from the hip to the knee and helps drain blood from the lower extremities.

• Torn Cartilage and Arthroscopy

  • In knee arthroscopy, for example, only two small incisions are made: one for the arthroscope, permitting observation of the procedure and one for the surgical instruments to be used in the knee cavity.
  • It is especially useful for professional athletes who frequently injure knee joints and require rapid healing.
  • The most common joints of the body that are successfully examined and or treated via this procedure include the knee, shoulder, elbow, wrist, ankle, foot, and hip.

• Tibia and Fibula (The Leg)

  • The tibia and the smaller fibula bones comprise the lower leg and articulate at the knee and ankle.
  • The tibia, or shin bone, spans the lower leg, articulating proximally with the femur and patella at the knee joint, and distally with the tarsal bones, to form the ankle joint.
  • Numerous internal ligaments of the knee joint attach to these tubercles and strengthen it significantly.