Human Anatomy- Chapter 9- Joints

The knee joint is also stabilized by 2 strong intracapsular ligaments called

cruciate ligaments 1. anterior cruciate ligaments (ACL) 2. posterior cruciate ligaments (PCL) they cross each other like an X.

Angular- 1. flexion

decreases the angle between the bones, bringing the bones closer together e.g. flexion of the neck or trunk flexion of the fingers making a fist forearm toward the arm

11. plantar flexion

depressing the foot elevating the heel

What functional classification of joints are common in the appendicular skeleton?

diarthroses

Which functional classification of joints are all synovial joints?

diarthroses

Synovial joints- 1. articular cartilage

ends of opposing bones are covered with hyaline cartilage - absorbs compression

Reinforcing ligaments can be ___ or ___

extracapsular ligaments or intracapsular ligaments

1. Gliding

flat surfaces of 2 bones slip across each other 1. carpals 2. tarsals 3. articular process of vertebrae "saying hi"

Ex. fingers making a fist

flexion

Ex. forearm toward arm

flexion

3. Diarthroses

freely moveable. common in appendicular skeleton (all synovial joints)

Knee joint primarily acts as a

hinge

1. Synarthroses

immovable; common in axial skeleton

2. Angular

increase or decrease the angle between two bones they include: 1. flexion 2. extension 3. abduction 4. adduction 5. circumduction

Functional classification is based on

is based on amount of movement 1. Synathroses 2. amphiarthroses 3. Diathroses

Arthr/o

joint elements of skeleton meets at joints or aticulations

1. elevation

lifting a body part superiorly

10. dorsiflexion

lifting the foot so its superior surface approaches the shin

3. protraction

moving a body part in the anterior direction

4. retraction

moving a body part in the posterior direction

2. depression

moving a body part inferiorly

Angular- 4. Abduction

moving away from the midline

Angular- 3. Circumduction

moving in a circle. combines flexion, abduction, extension and addiction. moving a limb or finger so that it describes a cone in space

7. opposition

moving the thumb to touch the tips of other fingers

Angular- 5. Adduction

moving toward the midline

4. Synovial fluid- Weeping lubrication

pressure on joints squeezes synovial fluid into and out of articular cartilage

Structure of the joints enable

resistance to crushing, tearing, and other forces

Angular- 2. Extension

reverse of the flexion occurs at the same joints. increases the angle between the joining bones and is a straightening action.

Joints

rigid elements of the skeleton meet at the joints or atriclations

6. supination

rotating the forearm so the palms face anteriorly -standard anatomical position

5. pronation

rotating the forearm to the palms face posteriorly - radius crosses ulna "x"

2. Amphiarthroses

slightly movable, common in axial skeleton

Which functional classification of joints are common in the axial skeleton?

synarthroses amphiarthroses

Name all the parts of the knee joint

*1. Lateral collateral ligament (LCL) *2. Medial collateral ligament (MCL) *3. Posterior cruciate ligament (PCL) *4. Anterior cruciate ligament (ACL) 5. Lateral condyle of femur 6. Medial condyle 7. Tibia 8. Fibula 9. Medial meniscus 10. Patellar ligament 11. Patella 12. Quadriceps tendon

4. Synovial fluid

- a viscous fluid similar to raw egg white - a filtrate of blood - arises from capillaries in the synovial membrane - contains glycoprotein molecules secreted by fibroblasts

Synovial joints- 3. articular capsule

- joint cavity is enclosed in a two layered capsule 1. fibrous layer 2. synovial membrane

Articular capusle. 2. synovial membrane

- loose connective tissue - lines joint capsule and covers internal joint surfaces - functions to make synovial fluid (inner layer)

5. Reinforcing ligaments

- often are thickened parts of the fibrous layer - sometimes are extracapsular ligaments- located outside the capsule -sometimes are intracapsular ligaments- located interal to the capsule

Synovial joints- 2. joint (articular) cavity

- unique to synovial joints - cavity is a potential space that holds a small amount of synovial fluid

Articular capsule- 1. fibrous layer

-dense irregular connective tissue, which strengthens joint (outer layer)

General structure of synovial joints

1. articular cartilage 2. joint cavity 3. articular capsule 4. synovial fluid 5. reinforcing ligaments (6. nerves and vessels)

Occur only in a few joints

1. elevation 2. depression 3. protraction 4. retraction 5. pronation 6. supination 7. opposition 8. inversion 9. eversion 10. dorsiflexion 11. plantar flexion

What are the two layers of the articular capsule?

1. fibrous layer 2. synovial membrane

Joints can be classified by

1. function 2. structure

Movements allowed by Synovial joints

1. gliding- one bone surface across another 2. angular- change the angle between 2 bones 3. rotation- about a bones long axis

The joint capsule of the knee is reinforced by several capsular and extracapsular ligaments

1. lateral collateral ligament LCL 2. medial collateral ligament MCL

What are the 2 fibrocartilage menisci that occur in the knee joint?

1. lateral menisci 2. medial menisci ( attach to condyles of tibia)

Structural classification is based on

1. material that binds bones together 2. presence or absence of a joint cavity 3. structural classifications include 1.fibrous 2. cartilaginous 3. synovial (need to know)

Structural classification- Synovial joints

1. most movable joint 2. all are diarthroses 3. each contain a fluid filled joint cavity (most joints in the body are this kind especially limbs)

Types of Synovial Joints

1. plane joint 2. hinge joint 3. pivot joint 4. condyloid joint 5. saddle joint 6. ball and socket joint

3. Rotation

turning movement. - lateral rotation - medial rotation

9. eversion

turning the sole of the foot laterally

8. inversion

turning the sole of the foot medially

6. Ball and socket joint

Movement: Flexion and extension Adduction and abduction and roation Structure: scapula and humerus os coxae and femur spherical head of one bone fits into a round socket in another

3. Pivot joint

Movement: Rotation Structures: ulna and radius or atlas and dens of axis rounded end of one bone fits into a ring that is formed by another bone

2. Hinge joint

Movement: flexion and extension Structures: Ulna and humerus cylindrical end of the bone fits into a trough shaped surface of another bone

4. Condyloid joint

Movement: flexion and extension adduction and abduction structures: phalanges and metacarpals egg shaped articular surface of one bone fits into an oval cavity of another - cannot rotate

5. Saddle joints

Movement: flexion and extension adduction and abduction structures: metacarpal 1 and trapezium - each articular surface has both convex and concave areas just like a saddle

1. plane joint

Movement: gliding Structures: metacarpals, carpals (flat planes)