1 / 53

Understanding the Knee Complex in Human Anatomy

Explore the general structure and function of the knee complex, including specific joints such as the tibiofibular, patellofemoral, and tibiofemoral joints. Learn about knee movements in different planes and the significance of the patella in knee function. Understand the implications of abnormal patella tracking and various skeletal abnormalities affecting the knee. Discover the factors contributing to abnormal knee tracking and potential compensatory mechanisms. Enhance your knowledge of knee anatomy for a better understanding of human movement.

elane
Download Presentation

Understanding the Knee Complex in Human Anatomy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Knee Complex

  2. The Knee Complex • General Structure & Function • Structure & Function of Specific Joints • Muscular Considerations

  3. General Structure

  4. Joints of the Knee Complex

  5. General Function • Provides very mobile link in an otherwise stable lower extremity • Transmits loads from tibia/fibula to femur

  6. Knee Complex Movements

  7. Transverse plane • Medial and lateral • rotation • Sagittal plane • Flexion, extension

  8. Knee Complex Movements • Frontal plane • Varus, valgus • Anteroposterior translation • Mediolateral translation

  9. The Knee Complex • General Structure & Function • Structure & Function of Specific Joints • Muscular Considerations

  10. Structure & Function of Specific Joints • Tibiofibular Joint • Patellofemoral Joint • Tibiofemoral Joint

  11. Tibiofibular Joint: Bony Structure Amphiarthrodial membranous syndesmosis joint

  12. Structure & Function of Specific Joints • Tibiofibular Joint • Patellofemoral Joint • Tibiofemoral Joint

  13. Purpose of Patella • Increase leverage of QF • Protect joint during knee flexion • ↓ pressure and distribute forces on femur • Prevent Fcompression on PT in resisted knee flexion • Disadvantage:  ANT shear of QF

  14. Patella Structure • Medial facet • Lateral facet • Odd facet (30%) M L

  15. Largest sesamoid bone Least congruent joint Articular cartilage Vertical ridge Facets M L PF Articular Surfaces

  16. Largest sesamoid bone Least congruent joint Articular cartilage Vertical ridge Facets Angle of femoral sulcus PF Articular Surfaces

  17. INF & SUP Sliding Patellar tilt 11 MT as KN FL Med Lat Patellar Motion

  18. Lateral rotation ACC MR of femur 6 through KN FL Medial rotation ACC LR of femur Patellar Motion

  19. Patellalectomy • ↓ MA of QF (↓ strength 49%) •  Q tendon friction •  compressive stress on groove by Q tendon • Most evident in closed chain EXT • ECC QF in CC • Coupled w/ & assisted by hip & ankle movement • QF not needed in erect posture of CC

  20. Extension Little effect overall

  21. Slight Flexion Noticeable weakness

  22. Extreme Flexion Noticeable weakness

  23. From 0° to 60° of Knee Flexion

  24. 0-60 • Contact area  •  MA of QF;  60 •  ANT shear of QF 0-60 • Facet contact at 20

  25. From 60° to 140° of Knee Flexion

  26. 60-140 •  contact area •  MA of QF • No leverage in full FL

  27. Overall • Medial facet most contact • Odd facet least contact

  28. During Full Extension Full EXT •  MA of QF •  QF length • Patella very unstable

  29. PF JRF • Amount of knee FL • Strength of QF contraction

  30. PF Compressive Forces

  31. Compensatory Mechanisms for Compressive Force Distribution • Contact area  with knee flexion • Medial facet contact from 30-70 • Thickest hyaline cartilage in body

  32. Compensatory Mechanisms for Compressive Force Distribution • Contact area  with knee flexion • Medial facet contact from 30-70 • Thickest hyaline cartilage in body • Largest QF MA 30-70 • QF torque as MA decreases • QF tendon contacts condyles 70-90

  33. Normal Patella Tracking • Maintains maximum congruence • Passive restraints • Active restraints

  34. Abnormal Patella Tracking • ↓ congruence • Stretches capsule & retinacula • ↓ contact area Lateral Medial

  35. Causes of Abnormal Tracking • Skeletal abnormalities • Strength imbalance in QF • Strength imbalance in fibrous tissues • Compensatory movements in knee due to abnormal foot movement

  36. Causes of Abnormal Tracking • Skeletal abnormalities • Strength imbalance in QF • Strength imbalance in fibrous tissues • Compensatory movements in knee due to abnormal foot movement

  37. Skeletal Abnormalities: Q-angle

  38. Skeletal Abnormalities: Genu Varum & Genu Valgum • Q angle  w/ age • Varum common in very young children • Valgum seen in growing children • Menisectomy effects

  39. Skeletal Abnormalities: Patella Alta & Patella Baja • Index of Insall & Salviti • LT/LP • Normal = 1.0 • Patella alta = 0.8 • Patella baja = 1.2 • Women  ratio

  40. Skeletal Abnormalities: Patella Surface Lateral Border • Appositional forces ↓ in full extension • Prominence of lateral border prevents lateral displacement • Underdevelopment common in children as growing

  41. Lateral tracking Skeletal Abnormalities: Femoral & Tibial Torsion

  42. Causes of Abnormal Tracking • Skeletal abnormalities • Strength imbalance in QF • Strength imbalance in fibrous tissues • Compensatory movements in knee due to abnormal foot movement

  43. QF Strength Imbalance

  44. Causes of Abnormal Tracking • Skeletal abnormalities • Strength imbalance in QF • Strength imbalance in fibrous tissues • Compensatory movements in knee due to abnormal foot movement

  45. Fibrous Tissue Strength Imbalance IT

More Related