Anatomy 1 - Chap 9 Joints

articular capsule

1. Structure that encloses the synovial Joint & synovial cavity; 2. two layers: fibrous capsule and synovial membrane

tendon sheath

1. ____is essentially an elongated bursa that wraps around a tendon like a bun around a hot dog. 2. occur only on tendons that are subjected to friction.

Synchondrosis

1. a joint where hyaline cartilage unites the bones 2. eg. epiphyseal plates (immovable) 3. eg. immovable joint between the first rib's costal cartilage and the manubrium of the sternum

Symphyses

1. a joint where the fibrocartilage unites the bones 2. slightlly movable joints that provide strength and flexibility 2. eg. intervertebral discs; pubic symphysis of the pelvis 4. hyaline cartilage is also present in the form of articular cartilage on the bony surfaces

articular disc

1. also known as meniscus it is a dense fibrous connective tissue that is thicker at the ends and attached to the condyle 2. composed of fibrocartilage, located within the joint cavity occur in the temporomandibular (jaw) joint, sternoclavicular joint, knee joint

Syndesmoses

1. bones are connected exclusively by ligaments 2. bands of fibrous tissue longer than those that occur in sutures 3. amount of movement allowed depends on the length of the connecting fibers. 4. eg. SHORT: distal tibiofibular articulation 5. eg. LONG: interosseous membrane between radius and ulna

saddle joint

1. each articular surface has both convex & concave areas (like a saddle) 2. classified as "BIAXIAL" 3. allow movement (1) flexion-extension (2) abduction-adduction 4. eg. bet. meta and carpal 1st carpometacarpal joint (thumb) - allows for oppostion of the thumb

synovial membrane

1. inner layer of articular capsule 2. composed of loose connective tissue 3. covers all the internal joint surfaces not covered by cartilage 4. function: to make synovial fluid

bursa

1. is a flattened fibrous sac lined by a synovial membrane 2. occur where ligaments, muscles, skin, tendons, or bones overlie each other and rub together

Flexion angular movement

1. is movement that decreases the angle between the bones, bringing the bones together 2. usually occurs in the sagittal plane of the body 3. eg. neck, trunk, shoulder, knee

Hyperextension movement of synovial joints

1. is the bending of a joint back beyond its normal range of motion 2. result: break or damage

Extension angular movement

1. is the movement that increases the angle between the joining bones and is a straightening action

Rotation movements of synovial joints

1. is the synovial joint movement turning of a bone around the longitudinal axis 2. only movement allowed between the first two cervical vertebrae (C1 & C2)

syndesmosis

1. joint held together by a ligament. 2. fibrous tissue can vary in length but is longer than in sutures

suture

1. joint held together with very short, interconnecting fibers, and bone edges interlock. 2. found only in skull

synovial joints

1. most movable joint of the body 2. all are diarthroses (freely movable) 3. contains a fluid-filled joint cavity 4. most joints of the body are in this class (limbs)

pronation synovial (special) movement

1. movements of the radius ACROSS the ulna; two bones form an "X" 2. rotating the forearm so the palm face posteriorly (hand lying "belly" side down - prone)

supination synovial (special) movement

1. movements of the radius AROUND the ulna (parallel) 2. rotating the forearm so the palm faces anteriorly (hand is lying on its "back" - supine)

opposition synovial (special) movement

1. moving the thumb to touch the tips of the other fingers 2. Human: fine tool for grasping and manipulating objects

fibrous capsule

1. outer layer of articular capsule 2. dense irregular connective tissue that is continuous with the periosteum layer of the joining bones 3. strengthens the joint so that the bones are not pulled apart

Gomphosis

1. peg-in-socket joint 2. periodontal ligament holds tooth in socket

joint capsule

1. reinforce joints 2. A sac enclosing a joint, formed by an outer fibrous membrane and an inner synovial membrane

Ball-and-socket joint

1. spherical head of one bone fits into a round socket in another 2. classified as "MULTIAXIAL" 3. flex-extend; abduct-adduct; rotation-circumduction eg. shoulder, hips

Plane (gliding) joint

1. the articular surfaces are essentially flat planes 2. only short gliding or translational movements are allowed 3. eg. intertarsal joints, intercarpal joints, joints bet. the articular processes of the vertebrae, ankles, wirst

Fibrous joints

1. the bones are connected by fibrous tissue (dense regular connective tissue) 2. no joint cavity present 3. immovable or slightly movable

sutures

1. the bones are tightly bound by a minimal amount of fibrous tissue 2. occur only between bones of the skull and their fibrous tissue is continuous with the periosteum around these flat bones 3. the edges of the joining bones are wavy and interlocking 4. not only knit the bones together but also allow growth so that the skull can expand with the brain during childhood

cartilaginous joints

1. the bones are united by cartilage 2. no joint cavity exists 3. not highly immovable

Hinge joint

1. the cylindrical end of one bone fits into a trough-shaped surface on another bone 2. angular movement is allowed in just one plane (door hinge): flexion-extension 3. eg. elbow joint, ankle joint, joints bet. the phalanges of the fingers; humerus & ulna 4. classified as "UNIAXIAL"

condyloid joints

1. the egg-shaped articular surface of one bone fits into an oval concavity in another 2. allow movement (1) flexion-extension (2) abduction-adduction 3. CAN'T rotate around its axis 4. classified as "BIAXIAL" - occurs around 2 axes 5. eg. metacarpal and phalanges

Gliding movement (wrist)

1. the movement of nearly flat surfaces of 2 bones slip across each other 2. occurs at the joints between the (1) carpals and tarsal (2) between the flat articular processes of the vertebrae

pivot joint

1. the rounded end of one bone fits into a ring that is formed by another bone + an encircling ligament 2. classified as "UNIAXIAL" - can only rotate around its long axis 3. eg. humerus-radius; atlas - dens of the axis

synovial fluid

1. viscous liquid (raw egg white) inside the joint cavity 2. primarily a filtrate of blood arising from capillaries in the synovial membrane 3. occupies the joint cavity and occurs within the articular cartilages

1. Plane Joint 2. Hinge Joint 3. Pivot Joint 4. Condyloid Joint 5. Saddle Joint 6. Ball-and-socket joint

6 Types of Synovial Joints

joints

Articulations between adjoining bones

muscle contract

As _______, they cause bones to move at the synovial joints.

1. articular cartilage - spongy cushion; end of opposing bones; absorb compressive forces - keep the bone ends from being crushed 2. joint cavity (synovial cavity) - potential space holding a small amt. of synovial fluid 3. articular capsule - 2 layers: fibrous capsule, synovial membrane 4. synovial membrane 5. reinforcing ligaments: extracapsular / intracapsular 6. nerves and vessels:

Basic features of synovial joints

1. Plane 2. (GOR) Gliding, Rotation-circumduction

Clavicle?

avascular

Describes any tissue that does not have a direct blood supply

Yes. Individuals who have loose ligaments that allow a greater range of motion

Is hyperextension possible without breaking or damaging the joints?

1. Synarthroses (no movement) - restricted to axial skeleton 2. Amphiarthroses (slight movement) - restricted to axial skeleton 3. Diarthroses (free movement) - limbs

Joints functional classification

1. Fibrous 2. Cartilaginous 3. Synovial

Joints structural classification

protective adaptation

Movement of the cranial bones would damage the brain, the immovable nature of sutures is a ___________

1. Gliding (one bone surface across another) 2. Angular movements (angle change between 2 bones) 3. Rotation (bone's long axis)

Movements allowed by Synovial Joints

1. Ball-Socket 2. (FAR) Flexion-Extension, Abduction-adduction, Rotation 3. mutiaxial

Shoulder?

1. inversion (medial) 2. eversion (lateral) 3. dorsiflexion (superior surface lift) 4. plantar flexion (pointing the toes)

Special synovial joint movement of the foot

weeping lubrication

Synovial fluid forced from cartilage during compression & soaked back up when pressure is relieved

1. Flexion (decrease angle bet. bones) 2. Extension (increase angle bet. bones) 3. Abduction (limb away from the body) 4. Adduction (limb toward the body) 5. Circumduction (limb or finger moving in a circle)

Types of Angular movements

1. synchondroses 2. symphyses

Types of Cartilaginous Joints

1. sutures 2. syndesmoses 3. gomphoses

Types of fibrous joints

circulate the nutrients/nourishes the cells of the articular cartilage and lubricates the joint surfaces

What are the functions of the synovial fluid?

1. based on the material that binds the bones together and 2. presence or absence of joint cavity

What is the basis of the structural classification of Joints?

1. dorsiflexion (raising the toes) 2. plantar flexion (pointing the toes)

What special movements found in ankles?

1. Inversion (rotate soles of feet toward the midline) 2. eversion (rotate soles of feet away from the midline)

What special movements found in feet?

1. protraction (palms down) 2. supination (palms up)

What special movements found in forearm at elbow?

1. elevation (raising) 2. depression (lowering) 3. protraction (push forward) 4. retraction (pull back)

What special movements found in jaw & shoulders?

opposition

What special movements found in thumb?

1. hyaline cartilage which covers the articular joint surfaces 2. fibrocartilage which unites adjoining bones

What types of cartilage are found in a symphysis joint?

articular cartilage

______________function to reduce friction between the bones during movement

intracapsular ligaments

are covered with a synovial membrane that separates them from the joint cavity through which they run

extracapsular ligaments

are located just outside the capsule, for instance, the fibular and tibial collateral ligaments of the knee

Special movements of synovial joints

certain movements of the synovial joints that do not fit into the gliding, angular, and rotation categories

1. by shape of surface 2. determines possible motions

classification basis of synovial joints

1. hinge joint 2. Flexion-extension 3. uniaxial

elbow?

plantar flexion synovial (special) movement

is a movement by DEPRESSING the foot or elevating the heel (pointing the toes)

dorsiflexion synovial (special) movement

is a movement by LIFTING the foot so its SUPERIOR SURFACE approaches the shin

elevation synovial (special) movement

is a movement by lifting a body part superiorly (eg. mandible)

protraction synovial (special) movement

is a movement by moving a body part in the anterior direction (eg. mandible)

retraction synovial (special) movement

is a movement by moving a body part in the posterior direction (eg. mandible)

depression synovial (special) movement

is a movement by moving a body part inferiorly (eg. mandible)

eversion synovial (special) movement

is a movement by turning the sole of the foot LATERALLY

inversion synovial (special) movement

is a movement by turning the sole of the foot MEDIALLY

uniaxial

is a movement that allows one axis only

biaxial

movement occurring around 2 axes

Abduction angular movement

movement of a limb away from the body midline

Circumduction angular movement

movement of a limb or finger so that is describes a cone in space

Adduction angular movement

movement of a limb toward the body midline

1. pivot 2. (R) Rotation only 3. uniaxial

radius and ulna (distal)

1. pivot 2. (RP) Rotation; Pronation-supination 3. uniaxial

radius and ulna (proximal)

lateral rotation

rotating away from the medial plane

medial rotation

rotating toward the medial plane

1. elevation & depression 2. protraction & retraction 3. supination & pronation 4. opposition 5. inversion & eversion 6. dorsiflexion & plantar flexion

special synovial joints movements

synostoses

the closed sutures are more precisely called ________