Articulation joints flashcards

Unit 2 Lecture slides Articulation

What is articulation? It is where two bones meet/connect. It sometimes allows movements and sometimes does not. Example, movement between Hummus and radius. Non movement Occipital bone and parietal bone in the skull.

The tendons connect the muscle to the bones and ligaments connect bone to bone.

What is Bursae? It is a pad that is made up of synovial membrane and has synovial fluid. Synovial flood is a thick, viscous liquid that lubricates and cushions the joints. Cushions muscle/bone/tendons.

A tendon sheath is a protective, tube-like structure that surrounds and encloses a tendon. It is made up of a thin layer of connective tissue called synovium, which produces a lubricating fluid that helps the tendon glide smoothly over bones and other tissues.

The meniscus is a C-shaped piece of tough, rubbery cartilage that acts as a shock absorber between the shinbone and the thighbone. It also helps hold the bone in position.

Fat pads located around joints help cushion and support.

Structural Joint Classification: 

Fibrous Joints: Fibrous joints are immovable or fixed joints that connect bones with dense fibrous connective tissue,with fibers of varying length. It is  primarily composed of collagen and has no joint cavity. A prime example of a fibrous joint is the sutures between the bones of the skull.

Cartilaginous Joints: The bones are connected by cartilage and it has no joint cavity. Example: Intervertebral discs (between vertebrae) and Pubic symphysis (between the two halves of the pelvis).

Bony Fusion: bone to bone fuse together and have no joint cavity. Sacrum, coccyx, and innominate bones. 

Synovial Joints: It consists of two bony surfaces surrounded by a fibrous capsule with a synovial lining. A synovial joint is a type of joint that allows for free movement in multiple planes. Examples : Hinge joints: Elbow, Knee, and Finger joints. 

Ball and socket joints: shoulder and hip. 

Pivot joints: Neck (atlantoaxial joint) and Forearm (radioulnar joint).

Synarthrosis  (together joint; tight joint)

As if the two bones were one. No movement allowed. Example: Skull Sutures.

Amphiarthrosis  (“so-so” joint ; little give)

A little bit of movement allowed. Wiggle but no spinning/hinging. Example: Pubic symphysis (between the two halves of the pelvis).

Diarthrosis  (separate joint; variable movement)

The two bones are distinctly two separate pieces. Freedom of movement between the bones. Bones allowed to shift past each other easily. Example: The elbow joint, the hip joints and shoulder joints.

Structural Joint Sub-Types for Fibrous Joints:

1) Suture (“sewing together”; “seam”)

•  synarthrosis functional joint

- Bones of the skull (child)

2) Syndesmosis (“held by bands”; “ligament”)

•  amphiarthrosis functional joint

- Between long bones of lower arm/leg

3) Gomphosis (“bolting together”; “tooth”) 

•  synarthrosis functional joint

- Teeth!

Structural Joint Sub-Types for Cartilaginous Joints:

1) Synchondrosis (“held by cartilage”)

-Made of Hyaline Cartilage

-synarthrosis functional joint

- Epiphyseal Plates, 1st Rib to Manubrium

2) Symphysis (“growing together”)

-Made of Fibrocartilage 

-amphiarthrosis functional

- Intervertebral discs, pubic symphysis

Structural Joint Sub-Types for Boney Fusion:

1) Synostosis (“held by bone”)

Bone joined to bone

synarthrosis functional joint

- Bones of the skull (adult)

Structural Joint Sub Types for Synovial Joints:

Bones are held together by a complex, fluid filled joint cavity. 

Variable movement allowed- diarthrosis functional joint

Most joints of the body (especially in appendages)

-Hips

-Shoulders

-Knees

-Elbows

Diarthrosis - Nonaxial has no plane of movement, limited “shifting”

Gliding – movement in no specific plane. Examples between carpals and tarsals. Clavicle to manubrium

Diarthrosis - Uniaxial (Monoaxial) has only one plane of movement – up/down or left/right

Hinge - elbow

Pivot – axis/atlas

Diarthrosis - Biaxial has two planes of movement – up/down and left/right

Saddle – thumb

Condyloid (Ellipsoidal) – phalanges/metacarpals

Diarthrosis - Triaxial 

Three planes of movement – up/down, left/right, and spin!

Ball and Socket Joint – hip, shoulder.