Chapter 9 Flashcards
What is a joint (articulation)?
Any point where 2 bones meet.
Why are joints needed?
They give mobility to the skeletal system.
What is the weakest structure of movement?
Joints
Because joints are the weakest of movement, you need…
Ligaments
What are ligaments?
Strips of collagenous tissue that attaches bone to bone.
What are ligaments made up of?
Dense regular connective tissue
What are joint classified by?
Structure and function
What is the main classification of joints?
The structure
The joint structure classification is determined by what?
- What materials bind them together.
- Joint cavity (is there a space between the bones)
The joint function classification is determined by what?
Movement
What is arthrology?
The science of joint structure, function, and dysfunction.
What is kinesiology?
The study of musculoskeletal movement.
What are the 3 joint structural classifications?
Fibrous joints, cartilaginous, and synovial.
What is the structural classification of fibrous joints?
Fibrous membrane in between the bones.
No joint cavity (no space between the bones).
What is the structural classification of cartilaginous?
Hyaline or fibrocartilage in between the bones.
No joint cavity (no space between the bones).
What is the structural classification of synovial joints?
Synovial membrane in between the bones.
Has a joint cavity (has space between the bones).
What are the 3 movement classifications in joints?
Synarthrotic, amphiarthrotic, and diarthrotic.
What does synarthrotic mean?
No movement
What is an example of a synarthrotic joint?
A fibrous joint
What does amphiarthrotic mean?
No movement
What is an example of an amphiarthrotic joint?
A cartilaginous joint
What does diarthrotic mean?
Has movement
What is an example of a diarthrotic joint?
A synovial joint
What is a fibrous joint?
Adjacent bones are bound by collagen fibers that emerge from one bone and penetrates into the other.
A fibrous joint is also called…
a synarthrosis
What are 3 kinds of fibrous joints?
Sutures, gomphoses, and syndemoses.
What are sutures?
Immobile fibrous joints that closely bind the bones of the skull to each other.
Where are sutures found?
Only in the skull
What is an example of a suture?
Squamosal, temporal, lambdoidal
What is a gomphoses?
The attachment of a tooth to its socket
Where are gomphoses found?
In the mouth
What are teeth held firmly in place by?
Fibrous periodontal ligaments
What are syndemoses?
A fibrous joint at which 2 bones are bound by relatively long collagenous fibers.
Where are syndemoses found?
Found in between the ulna and radius, and between the tibia and fibula.
What fibrous joint has the most mobility?
Syndemoses
What is interosseous membrane?
A thick, dense fibrous sheet of connective tissue that spans the space between 2 bones forming a type of syndemosis joint.
Where is interosseous membrane found?
Found between the shafts of the radius and ulna.
What is a cartilaginous joint?
2 bones that are lined by cartilage.
A cartilaginous joint is also called…
Amphiarthrosis
What are 2 types of cartilage bones?
Synchondroses and sympheses
What is a synchondrosis?
Bones joined by hyaline cartilage.
What are examples of synchondrosis joints?
Temporary joint between epiphysis and diaphysis of a long bone in a child. First rib attachment to the sternum.
The other 11 ribs are attached to the sternum by…
Synovial joints
What is a symphysis joint?
2 bones joined by fibrocartilage
What are examples of a symphysis joint?
Pubic symphysis joint, bodies of vertebrae joined by intervertebral discs.
What is a synovial joint?
Joint in which 2 bones are separated by a joint cavity.
A synovial joint is also called…
Diarthrosis
What is an example of a synovial joint?
Elbow, knee or knuckle
What is the most common and most widespread joint?
Synovial joint
All synovial joints are highly __________ and highly ________.
Vascularized, innervated
What do synovial joints need?
Blood
What does the synovial membrane make?
It makes synovial fluid from blood vessels.
What is the general structure of synovial joints?
- Articular cartilage
- Joint cavity
- Synovial fluid
- Joint capsule
- Articular disc
- Meniscus
What is articular cartilage?
A layer of hyaline cartilage covering the facing surfaces of 2 bones. It’s usually 2-3 mm thick.
Where is articular cartilage found?
Found on the ends of bones.
What is the function of articular cartilage?
Reduces friction between bones.
What does an articular joint cavity do?
Separates articular surfaces.
What is synovial fluid?
Slippery lubricant in joint cavity.
Synovial fluid has a slippery texture similar to…
Raw egg whites
What is the function of synovial fluid?
It nourishes the articular cartilages, removes their wastes, and makes movements at synovial joints almost friction-free.
What is a joint (articular) capsule?
Connective tissue that encloses the cavity and retains the fluid.
What are the 2 layers of a joint capsule?
Outer fibrous capsule and inner cellular synovial membrane.
What is the outer fibrous capsule of a joint capsule made up of?
Dense irregular connective tissue
The outer fibrous capsule is continuous with…
the periosteum of adjoining bones.
What is the inner cellular synovial membrane of a joint capsule made up of?
Areolar connective tissue with some elastic fibers.
What is the inner synovial membrane of a joint capsule?
It is composed of mainly fibroblast-like cells that secrete synovial fluid and macrophages that remove debris from the joint cavity.
What are the accessory structures associated with synovial joints?
Tendons, ligaments, bursa, and tendon sheaths.
What are ligaments in synovial joints? What are they needed for?
The thickened part of the fibrous capsule. They are needed to reinforce the joint.
What is a bursa?
An isolated pocket of synovial fluid, lined by synovial membrane.
What are the functions of a bursa?
Cushion muscles, help tendons slide more easily over the joints, and sometimes enhance the mechanical effect of a muscle.
What is a tendon (synovial) sheath?
An elongated bursa wrapped around a tendon.
What is the function of a tendon sheath?
They enable tendons to move back and forth freely in tight spaces.
Where are tendon sheaths found?
In the hand and foot
What are synovial joints based on?
They’re based on the shape of the articulating surfaces (bone ends).
What are the 6 different types of synovial joints?
Planar joints, pivot joints, hinge joints, condyloid joints, saddle joints, and ball & socket.
What is a planar joint?
The ends of the bones are plane (flat).
What is the movement of planar joints?
Gliding
What are planar joints found?
Between the carpal bones of the wrists, the tarsal bones of the ankle, and the articular processes of the vertebrae.
What are pivot joints?
The head of one bone fits into a sleeve of another.
What is an example of a pivot joint?
Radius and ulna, C1 and C2
What is a hinge joint?
It’s a monaxial joint, moving freely in one plane, with very little movement in any other, like a door hinge.
What is an example of a hinge joint?
Elbow, knee
What is a condyloid joint?
These joints have an oval convex surface on one bone that fits into a complimentary-shaped depression on the other.
What is an example of a condyloid joint?
Metacarpal phalanges joint of 2 to 5 digits.
What is a saddle joint?
Both bones have a saddle-shaped surface. One surface is concave (front-to-rear curvature) and one surface is convex (left-to-right curvature).
What is an example of a saddle joint?
Joint between the first metacarpal and the trapezium.
What is a ball and socket joint?
One bone has a smooth head that fits into a cuplike socket on the other.
What is an example of a ball and sock joint?
Head of the humerus, glenoid cavity of scapula.
What are movements of synovial joints classified as?
Gliding movements, rotational movements, Angular movements, and special movements.
What is an example of a gliding movement?
Waving
What are the 2 rotational movements?
Lateral rotation - away from the midline
Medial rotation - toward the midline
What are the 5 types of angular movements?
- Flexion - small angle created between bones
- Extension - large angle created between bones
- Adduction - away from the midline
- Abduction - bringing it closer together
- Circumduction - doing the 4 together in this order: flexion, adduction, extension, abduction. * Like drawing a circle in space.
What are the 11 types of special movements?
- Protraction - pulling forward
- Retraction - taking back
- Elevation - lifting up
- Depression - going down
- Supination - 2 bones are parallel facing up
- Pronation - 2 bones are parallel facing down
- Opposition - thumb touching the tip of the other 4 fingers
- Inversion - inward
- Eversion - outward
- Plantar flexion - curling your toes inward
- Doriflexion - fan your toes upward
What 4 types of special joint movements only happen in the feet?
Innversion, eversion, plantar flexion and dorsiflexion.
