1. Joint Classification (Function/Structure) • Synarthroses (immovable) / mostly fibrous Joint Sutures Gomphosis • Amphiarthoses (slightly movable) / mostly cartilaginous Joint Syndesmoses Synchondroses Symphyses • Diarthroses (freely movable) / Synovial Joint A.K.A – synovial joint, articular joint Six main types

2. Sutures

3. Syndesmoses

4. Synchondroses

5. Symphyses

6. Types of Synovial Joints

7. Joint Structures • Joint Capsule • Ligaments • Articular Cartilage • Meniscus and Labrum • Bursa • Fat Pads • Muscles*

8. Joint Capsule (Articular or Synovial Capsule) • Fibrous Capsule • Synovial Membrane • Synovial Fluid

9. Ligaments (Tendons)Function • Ligaments – connect bone to bone • Tendons – connect muscle to bone • Both specialize in resisting tensile forces

10. Ligaments (Tendons)Composition and Structure • Collagen and Elastin Strength (tensile) - tropocollagen Flexibility • Vascularization Limited • Parallel fibers – tropocollagen Crimp structure Load / deformation

11. Structure of ligaments versus tendons

12. Crimp (wavy) structure

13. Load / Deformation Curves

14. Factors That Affect the Properties of Ligaments and Tendons • Maturation and Aging < 20 years progressive ↑ in tensile strength > 20 years progressive ↓ in tensile strength; especially at the insertion points • Exercise ↑ structural strength and stiffness (Wolf’s Law) Benefits are moderate • Disuse 8-9 week immobilization - progressive ↓ tensile strength with slow recuperation to normal strength (12 months)

15. Articular Cartilage • Shock Absorption (viscoelastic nature) • Improves the fit and reduces pressure (P = F/A) • Spreads synovial fluid

17. Meniscus (Knee) • Improves Stability • Screw-home mechanism • Poor healing (fibrocartilage)

18. Labrum (glenohumeral and acetabular) • Improves Stability -deepens the socket • Poor healing (fibrocartilage)

19. Bursa • Produces synovial fluid • Reduces friction • Subcutaneous Prepatellar Bursa (prepatellar bursitis)

20. Fat Pads

21. Joint Flexibility Measurement • Range of Motion (ROM) – angle through which a joint moves from anatomical position to the extreme limit of segment motion in a particular direction • Absolute versus Relative angle measurement • Goniometer / Electrogoniometer

22. Stretching Techniques • Active versus Passive Stretching • Ballistic versus Static Stretching

23. Multijointed Muscles • Active Insufficiency (muscle contraction) – limited ability of a multijointed muscle to produce force when joint position places the muscle on slack • Passive Insufficiency (muscle stretching) – inability of a multijointed muscle to stretch to the extent required to allow full ROM at all joints crossed

24. Hamstring Curls

25. Neuromuscular Response to Stretch • Golgi Tendon Organs (GTOs) • Advantages with stretching • Propioceptive Neuromuscular Facilitation (PNF) • Muscle Spindles and Stretch Reflex • Triggered by ballistic stretching • Advantages with muscle contraction

26. Golgi Tendon Organ (GTO)

27. Muscle Spindle