1. knee
    joint structure and motions
    complex joint

    supported and mainted byu muscles and ligaments

    lacks bony stability

    exposed to severe stresses and strains

    one of the most injured joints in the body
  2. joint structure and motins
    largest joint in the body

    • synovial hinge joint
    • not a true hinge
    • has a rotational component
    • accompanies other motions


    • flexion-120-135
    • extension 0
  3. screw home mechanism
    understand, probably not on test
    • medial femoral condyle longer than lateral condyle
    • as extension occurs, the articular surface of lateral condyle used up while 1/2" remains medially

    therefore the medial condyle must glide posteriorly to use all of its articular surface

    with knee extension in a non-weight bearing (NWB) position the femur rotates medially on the tibia
  4. during knee extension
    • closed chain-foot on the floor
    • femur rotates medially/internally on the tibia

    open chain=foot not on the floor

    tibia roatates laterally/externally on the tibia
  5. femur parts
    • head
    • neck
    • greater trochanter
    • lesser trochanter
    • body
    • medial condyle
    • lateral condyle
  6. tibia
    • medial lateral condyle
    • tibial plateau
    • intercondylar eminence
    • tibial tuberosity'
    • crest
    • medial malleolus(inside ankle bone)
  7. fibula
    • lateral to and smaller than tibia
    • posterior to tibia
    • not part of the knee joint
    • NO articulation with femur
    • larger role at ankle

    • patella
    • tibia
    • fibula
    • fibular head
    • lateral malleolus
    • calcaneus
  8. patella
    triangular shaped sesamoid bone

    within quadriceps muscle tendon

    broad superior border

    distally somewhat pointed
  9. patellofemoral joint
    articulation between the femur and patella

    • patella's functions:
    • increases mechanical advantages of quadriceps muscle
    • protect knee joint
  10. Q angle=patellofemoral angle
    • angel between:
    • quadriceps muscle (rectus femoris
    • patellar tendon

    • draw a line from anterior superior iliac sping to midpoint of the patella
    • normal angle ranges 13-18
    • Q angle> in females

    related to many different knee & patellar problems-pain
  11. ligaments and other structures
    • knee held together by ligaments and muscles
    • ligaments
    • cruciates-crossing ligaments
    • collaterals
    • menisci
    • bursa
    • popliteal space
    • pes ansenine(gooses foot)
    • sartorius, gracilis, & semitendinosus
  12. ligaments & other structures cruciates
    place palm over knee

    • cross third finger over second finger
    • 3rd finger=anterior cruciate ligament
    • 2nd finger=posterior cruciate ligament
  13. anterior cruciate ligament
    runs from anterior tibia to posterior femur

    • prevents anterior tibial displacement
    • tight during extension

    runs from posterior tibia to anterior femur

    • prevents posterior tibial displacement
    • tight duriung flexion
  14. medial collateral ligament
    • medial collateral=tibial collateral
    • attaches to medial meniscus
    • may see associated injuries

    • medial stability
    • prevent excess motion from blow to lateral side
  15. lateral collateral ligament
    lateral collateral=fibular collateral

    strong, seldom injured

    • lateral stability
    • prevent excess motion from blow to medial side
  16. bursa
    purpose-reduce friction

    13 located at knee

    necessary because of the many tendons having a relatively vertical line of pull against bony areas and other tendons
  17. popliteal space
    area behind the knee

    • contains nerves and blood vessels
    • tibial nerve
    • common peroneal nerve
    • popiteal artery and vein

    diamond-shaped fossa

    • superomedial
    • semitendinosus
    • semimembranosus
    • superolateral
    • biceps femoris
    • inferior-medial/lateral heads
    • gastrocnemius
  18. muscles of the knee
    • anteriorly
    • 1-joint
    • vastus lateralis,
    • medialis,
    • intermedialis

    • 2-joint
    • rectus femoris


    • 2-joint
    • tensor lascia latae

    • Posteriorly
    • 1-Joint Muscles
    • Biceps femoris (short head)
    • Popliteus

    2-Joint Muscles

    • Biceps femoris (long head)
    • Semimembranosus
    • Semitendinosus
    • Sartorius
    • Gracilis
    • Gastrocnemius
  19. other muscles
  20. •Gracilis, sartorius, and tensor fascia latae span knee posteriorly
    • –Provide stability to the knee
    • –Do not have a prime-mover function
    • •Size
    • •Angle of pull
    • •Tensor fascia latae
    • –Contributes to lateral stability
    • •Gracilis and sartorius
    • –Contribute to medial stability
    • •Gastrocnemius and hamstrings
    • –Medial and lateral stability
    • •Quadriceps
    • –Anterior stabilizer
  21. varus
    position in which the distal segment is located toward the midline
  22. valgus
    position in which the distal segment is situated away from the midline
Card Set