A Joint

~Allows motion, bears weight of body and provides

                                    stability.

~Also contains synovial fluid which lubricates the joint and nourishes the cartilage.

very little

"For everything that is given something is taken away"

Fibrous Joint

Synarthrosis- Sutures of the skull

               Ex. Bones in the skull

Syndesmosis- ligamentous

                Ex. Distal tibiofular

Gomphosis- "Peg in socket"

                     Ex.  Teeth in Mandible & Maxilla

Amphiarthrosis Joints

"Cartilaginous joints"

Diarthrosis

"synovial joint"

A cavity filled with synovial fluid within a sleevelike capsule.

Outerlayer- fibrous tissue holds jt together.

Inner layer- lined w/ synovial membrane that secrets 

                   synovial fluid.

Articular surface- very smooth, covered w/ hyaline or

                  articular cartilage

Plane                     Hinge                            Pivot

Condyloid              Saddle                  Ball and Socket

Diarthrosis: Classification

Irregular joint: irregular surfaces, flat or slightly curved, permits gliding movement

Example? Joint motion?

Intercarpal

Gliding

Diarthrosis: Classification

Hinge joint: Convex/concave surfaces, uniaxial, permits flexion/extension

Example? Joint motion

Elbow, Knee, Phalanges

flexion/extension rotation

Diarthrosis: Classification

Pivot Joint: a peg-like pivot, permits rotation

uniaxial 

Example? Joint motion

Atlantoaxial

C1/C2

Rotation

Diarthrosis: Classification

Condyloid Jt: oval or egg-shape convex surfaces fit into a reciprocal concave surface, permits flexsion/extsion, Ab & adduction, & circumduction 

 Biaxial

Example? Joint Motion

MCP "knuckles"

Radiocarpal "wrist jt"

Flex/Ext ab & adduction

Diarthrosis: Classification

Saddle: modification of condyloid, both surfaces are convex & concave

biaxial

Example?Joint motion

Thumb "1st CMC"

Flex/Exten, Ab & Adduction

roation (accessory)

Diarthrosis: Classification

Ball & Socket: head of one bone fits into the cup of the other bone

Example?

Movement tends to be linear, jt surfaces relatively flat & glide over one another

Example: Motion between carpal bones

occurs in two different directions

ie. the wrist, ext/flex occur in frontal axis & radial and ulnar deviation occur around the saggital axis.

Biaxial Joint

"Condyloid or Ellipsoidal" Joints

Bi-directional motion

Ex. metaphalangeal joints

Biaxial Joint

Carpometalcarpal CMC joint of the thumb

Saddle Joint

Flexion/Extension,

Ab & adduction

Rotation (accessory)

Triaxial Joint

"multiaxial joint"

Ball and Socket Joint

Movement occurs actively in all three axes.

hip/shoulder allow motion in frontal axis,

in the sagittal axis, and in the vertical axis

Ligaments

Bands of fibrous connective tissue, provide attachment for cartilage, fascia, or in some cases muscle.

Ligaments are flexible, but not elastic 

1. Ligaments- bone on bone

2. Muscle tension - muscle to bone

3. Fascia- connective tissue

4. Atmospheric pressure

5. Bony structure

Hyaline "articular" cartilage

Fibrocartilage

Elastic Cartilage

Covers ends of opposing bones

Has no bld or nerve supply gets its nutrition from synovial fluid. 

When damaged unable to repair itself

acts as shock absorber

espcially important in weight-bearing jts.

Example: knee & vertebrae

helps maintain shape and structure

Found in external ear & eustachian (auditory tube) also found in layrnx

Fracture

"Broken bone"

complete seperation of the two articular surfaces of a joint.

Common example of shoulder subluxation dvlps after a stroke

Muscle paralysis & the weight of the arm slowly subluxes the shoulder jt.