1. Biology 211 Anatomy & Physiology I
Dr. Thompson
Joints

2. Last week: Defined bones as organs of skeletal system
Also organs: joints (one or more types of tissues, all serving a common function)

3. Joints are classified using two chararacteristics
1. What type of tissue connects the bones at the joint
2. How much motion the joint allows
Ordinary connective tissue = Fibrous
Hyaline or Fibrous cartilage = Cartilagenous
Fluid-filled capsule (synovium) = Synovial
No motion = Synarthrosis
Limited motion = Amphiarthrosis
Freely movable = Diarthrosis

5. Fibrous Joints:
Bones connected by dense regular or dense irregular
connective tissue with many collagen fibers.
No joint cavity.
Depending on length of collagen fibers, may be synarthrotic (no motion) or amphiarthrotic (limited motion)

6. Fibrous Joints:
Three subtypes:
1. Suture:
Collagen fibers very short
Always synarthrotic
Only in skull

7. Collagen fibers longer Amphiarthrotic (some motion)
Fibrous Joints:
Three subtypes:
(1. Suture: Collagen fibers very short, synarthrotic, only in skull)
2. Syndesmosis
Collagen fibers longer
Amphiarthrotic (some
motion)

8. Collagen fibers very short Synarthrotic (no motion)
Fibrous Joints:
Three subtypes:
(1. Suture: Collagen fibers very short, synarthrotic, only in skull)
(2. Syndesmosis: Collagen fibers longer, amphiarthrotic)
3. Gomphosis:
Collagen fibers very short
Synarthrotic (no motion)
Teeth in mandible or maxilla

9. Cartilagenous Joints:
Bones connected by some form of cartilage
No joint cavity.
Depending on length of collagen fibers, may be synarthrotic (no motion) or amphiarthrotic (limited motion)

10. Cartilagenous Joints:
Two subtypes:
1. Synchondrosis:
Bones connected by hyaline cartilage
Synarthrotic or amphiarthrotic
Costosternal; Epiphyseal plates

11. Cartilagenous Joints:
Two subtypes:
(1. Synchondrosis: Bones connected by hyaline cartilage
Synarthrotic or amphiarthrotic; Costosternal; Epiphyseal plates)
2. Symphysis:
Bones connected by fibrous cartilage
Amphiarthrotic or
synarthrotic
Intervertebral disks;
Pubic symphysis

12. Synovial Joints:
Bones separated by synovial joint cavity;
connected by ligaments of dense regular C.T.
Most synovial joints are diarthrotic
Some are amphiarthrotic

13. Synovial Joints:
Components:
Proximal bone with
articular cartilage
Distal bone with
articular cartilage
Articular capsule with:
Fibrous capsule
Synovial membrane
surrounding
Synovial cavity
Ligaments of dense irregular C.T.
Intrinsic = thickenings of fibrous capsule
Extracapsular = outside of fibrous capsule
Intracapsular = inside synovial cavity

14. Proximal bone with articular cartilage
Synovial Joints:
Proximal bone with articular cartilage
Distal bone with articular cartilage
Articular capsule with Fibrous capsule,
Synovial membrane surrounding Synovial cavity
Intrinsic ligament = thickenings of fibrous capsule
Extracapsular ligament = outside of fibrous capsule
Intracapsular ligament = inside synovial cavity
In knee, sternoclavicular, and
temporomandibular joints:
Also meniscus of fibrous cartilage

15. Synovial Joints:
Six types based on structure and type of motion:

16. Synovial Joints: Six types
1. Plane or Gliding
Gliding motion along
flat articular surfaces.
Amphiarthrotic

17. Synovial Joints: Six types
2. Hinge joint
Motion around single
axis perpendicular to
long axis of bones.
Often convex articular
surface on one bone
and concave articular
surface on other
bone.
Diarthrotic

18. Synovial Joints: Six types
3. Pivot joint
Motion around single
axis parallel to long
axis of bones.
Often convex articular
surface on one bone
and concave articular
surface on other
bone.
Diarthrotic

19. Synovial Joints: Six types
4. Condyloid joint
Motion around two
axes.
Articular surfaces of
both bones round or
oval.
One shallowly convex.
One shallowly concave
Diarthrotic

20. Synovial Joints: Six types
5. Saddle joint
Motion around two
axes.
Articular surfaces of
both bones are:
Convex one direction
Concave other direction
Diarthrotic

21. Synovial Joints: Six types
6. Ball & Socket joint
Motion around all three
axes.
Articular surfaces of one
bone forms "ball" which
fits into "socket" on other
bone
Diarthrotic

22. We’ve noted that Synovial joints are stabilized by
Shapes of the articular surfaces of bones
Ligaments
Menisci
They are also stabilized by muscles and tendons which cross over the joint

23. Synovial joints often cushioned by a fluid-filled sac called a bursa located between the joint and overlying muscles, tendons, or ligaments.

24. The following six specific synovial joints are described
In your Saladin text:
Jaw (Temporomandibular)
Shoulder (Humeroscapular)
Elbow (Humeroulnar, Humeroradial, Radioulnar)
Hip (Femorocoxal or Coxal)
Knee (Tibiofemoral)
Ankle (Talotibial, Talofibular)
On exams, you should be able to briefly but accurately describe the structure of each of these joints, including all major ligaments; and you should be able to describe the actions for each

25. Movements of synovial diarthrotic joints:
Flexion and Extension

26. Movements of synovial diarthrotic joints:
Abduction and Adduction

27. Movements of synovial diarthrotic joints:
Rotation and Circumduction

28. Movements of synovial diarthrotic joints:
Protraction and Retraction

29. Movements of synovial diarthrotic joints:
Elevation and Depression

30. Movements of synovial diarthrotic joints:
Inversion and Eversion

31. Movements of synovial diarthrotic joints:
Opposition (and Reposition)