Post on 23-Dec-2015
The Knee Joint
Anatomy and Physiology of Human Movement
420:050
Objectives
Bones, bony landmarks and joints Muscles Movements
Knee Joint Large joint Complex ligamentous structures Femoral condyles articulate with tibial condyles Medial/lateral tibial condyles (aka plateaus) – act
as receptacles for femoral condyles Relatively stable joint despite injuries
Ligaments Menisci Quadriceps and hamstrings
Modified from Anthony CP, Kolthoff NJ: Textbook of anatomy and physiology, ed 9, St. Louis, 1975, Mosby.
Modified from Anthony CP, Kolthoff NJ: Textbook of anatomy and physiology, ed 9, St. Louis, 1975, Mosby.
Bones and Bony Landmarks Tibia:
Bears weight Fibula:
Serves as the attachment sight Does not articulate with femur or patella Not part of knee joint
Patella: Sesamoid bone imbedded in patellar tendon Improves mechanical advantage in knee extension
Bony landmarks same as the hip joint
Lateral femoral epicondyle Medial femoral
epicondyle
Patella
Tibial tuberosity
Head of fibula
Lateral tibial condyle
Medial tibial condyle
Joint Knee joint
Diarthrodial uniaxial hinge joint Movements Planes and axes
Patellofemoral joint Diarthrodial nonaxial gliding joint Gliding nature of patella on femoral
condyles
Objectives
Bones, bony landmarks and joints Muscles Movements
Muscles Quadriceps
Rectus femoris Vastus medialis Vastus lateralis Vastus intermedius
Hamstrings Biceps femoris Semimembranosus Semitendinosus
Sartorius Gracilis Popliteus Gastrocnemius
Rectus Femoris
Vastus Medialis
Vastus Lateralis
Vastus Intermedius
Biceps Femoris
Semimembranosus
Semitendinosus
Sartorius
Gracilis
Popliteus
Gastrocnemius
Objectives
Bones, bony landmarks and joints Muscles Movements
Movements
Flexion Bending or decreasing angle
between femur and shin Extension
Straightening or increasing angle between femur and shin
Movements
External rotation Rotary movement of leg laterally
away from midline Internal rotation
Rotary movement of lower leg medially toward midline
Neither will occur unless flexed 20-30 degrees or more
LINE OF PULL
FLEXION
Bending or decreasing angle between femur and shin
Popliteus
FLEXION
FLEXION
Biceps femoris Semimebranosus Semitendinosus Sartorius Gracilis Popliteus Gastrocnemius
EXTENSION
Straightening or increasing angle between femur and shin
EXTENSION
EXTENSION
Rectus femoris Vastus lateralis Vastus medialis Vastus intermedius