1. The Knee Joint Anatomy and Physiology of Human Movement 420:050

2. Objectives Bones, bony landmarks and joints Muscles Movements

3. 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

4. Modified from Anthony CP, Kolthoff NJ: Textbook of anatomy and physiology, ed 9, St. Louis, 1975, Mosby.

6. 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

9. Lateral femoral epicondyle Medial femoral epicondyle Patella Tibial tuberosity Head of fibula Lateral tibial condyle Medial tibial condyle

10. Joint Knee joint Diarthrodial uniaxial hinge joint Movements Planes and axes Patellofemoral joint Diarthrodial nonaxial gliding joint Gliding nature of patella on femoral condyles

11. Objectives Bones, bony landmarks and joints Muscles Movements

12. Muscles Quadriceps Rectus femoris Vastus medialis Vastus lateralis Vastus intermedius Hamstrings Biceps femoris Semimembranosus Semitendinosus Sartorius Gracilis Popliteus Gastrocnemius

13. Rectus Femoris

14. Vastus Medialis

15. Vastus Lateralis

16. Vastus Intermedius

17. Biceps Femoris

18. Semimembranosus

19. Semitendinosus

20. Sartorius

21. Gracilis

22. Popliteus

23. Gastrocnemius

24. Objectives Bones, bony landmarks and joints Muscles Movements

25. Flexion Bending or decreasing angle between femur and shin Extension Straightening or increasing angle between femur and shin

26. 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

27. LINE OF PULL

28. FLEXION Bending or decreasing angle between femur and shin

29. Popliteus

32. FLEXION

33. Biceps femoris Semimebranosus Semitendinosus Sartorius Gracilis Popliteus Gastrocnemius

34. EXTENSION Straightening or increasing angle between femur and shin

37. EXTENSION

38. Rectus femoris Vastus lateralis Vastus medialis Vastus intermedius