Joints

Cartilaginous joints

Bones are connected by either hyaline cartilage or fibrocartilage in cartilaginous joints. Includes synchondroses and symphyses

Fibrous joints allow no movement, and cartilaginous joints allow slight movement.

False-Syndesmoses are fibrous joints that allow slight "give" movements. Also, synchondroses are cartilaginous joints that do not move at all.

By the age of 21, the long bones are no longer able to grow in length due to closure of the epiphyses. The total number of joints in the body of an adult, therefore, is ________ the number of joints in a growing child.

Fewer than

Hinge joints,

Joints that can bend and straighten but cannot rotate; they restrict motion to one plane. -ex: elbow

abduction

Movement away from the midline of the body

opposition

Movement of the thumb to touch the fingertips

adduction

Movement toward the midline of the body

triaxial joints

ball-and-socket joints, and the numerous gliding (plane) joints, which can be considered nonaxial.

dorsiflexion

bending of the foot at the ankle in an upward position

plantar flexion

bends the foot downward at the ankle

rotation

bone revolves around its own longitudinal axis -ex: turning head from side to side

Syndesmoses

bones are connected by an interosseous ligament. Only allows a slight shift or give movement. ex-ligament joining the tibia and fibula

Synovial

bones held together by ligaments

aging effects on joints

by 80, Include decrease in production of synvial fluid, reduction in thickness of articular cartilage, and lose of ligament length/flexibility. Are due to genetic factors as well as wear and tear.

Sutures

connect the membranous bones of the skull, and are rendered immovable.

Bones are joined by

connective tissue

types of synovial joints

plane, hinge, pivot, condyloid, saddle, ball and socket

Range of Motion

refers to the normal extent of mobility for a specific joint movement, and typically refers to the movement possible at the freely movable synovial joint.

Degrees of Freedom

refers to the number of axes at which movement in joint occurs

Pivot joints

rotate about a longitudinal axis and feature an articular surface shaped like a cylinder, which rotates within a ring formed of bone and ligament. -ex: atlanto-axial joint,proximal radioulnar joint

Synovial fluid is derived from:

serum -that filters into the joint space from capillaries in the synovial membrane

Which of the following is an example of rotation?

shaking your head no

Amphiarthrosis

slightly movable joint

Functional

synarthrosis, amphiarthrosis, diarthrosis

Fibrous joints that are also amphiatrhoses include:

syndesmosis

Gomphosis

teeth articulate with the maxillary and mandibular sockets via gomphosis joints. The connective tissue fibers that radiate from the tooth's root form the periodontal ligaments. They are consisdered immovable

What distinguishes the three different fibrous joints?

the length of connective tissue fibers joining the bones together

Articulation (joint)

the meeting place of two or more bones

Compared to the shoulder, the hip has ________ degrees of freedom and ________ range of motion.

the same;less

Synostosis

the suture between the two frontal bones in infants also usually ossifies to form a single frontal bone

The joint capsule's outer layer is made of:

dense fibrous connective tissue, which is continuous with the periosteum of the articulating bones.

The joint capsule is typically reinforced by:

extracapsular ligaments

ball and socket joint

feature a spherical surface (humeral and femoral heads) articulating with a cup-shaped socket -ex: shoulder and hip

In some synovial joints, including the jaw and knee:

fibrocartilage (articular) discs improve the fit of articulating bones and provide structure and support.

Structural

fibrous, cartilaginous, synovial -the differ not only by the type of tissue conncting the bones, but alse by whether a fulid-filled joint cavity is present

gliding movement

flat bone surfaces move back and forth and from side to side -ex: intercarpal joints, intertarsal joints

Diarthrosis

freely movable joint

4 categories of joint movement

gliding, angular movements, rotation, special movements

Uniaxial joints

have one axis of rotation, providing one degree of freedom and one movement pair (thus one plane of movement) - includes hinge and pivot

Biaxial joints

have two axes of rotation, and thus two planes of movement. The movement pairs allowed are flexion-extension and abduction-adduction. -includes Condyloid (or ellipsoid) joints, and saddle joints

The humeroulnar joint is what type of synovial joint?

hinge

What tissue covers the articulating surfaces of bones in a synovial joint?

hyaline cartilage

The articulating ends of bones entering into synovial joints are covered with

hyaline cartilage -which is a remnant of the original hyaline cartilage model from which each bone was formed by endochondral ossification

Synarthrosis

immovable joint

angular movements

increase or decrease the angle between two bones -includes flexion, extension, abduction, adduction, and circumduction

extension

increases the angle of a joint -hyperextension: continuation of extension beyond normal

What components of sutures give this joint great strength?

inter connecting tissue fibers and interlocking bones

synovial joints

joint capsule, ligaments, bursae, articular discs, labrum

Unlike other joint types, synovial joints feature a:

joint cavity that is formed by enclosing the articulating bones with a joint capsule

Compared to a suture, a syndemosis has ______ connecting bones and allows ______ movement.

longer fibers; more

protraction

movement anteriorly -ex: thrusting mandible outward

retraction

movement back to normal

circumduction

movement of body part in a cirlce

inversion

movement of the foot medially

supination

movement of the forearm -ex: palm is turned anterior

pronation

movement of the forearm -ex: palm is turned posterior

eversion

moving foot laterally

elevation

-An upward movement of a part of the body -ex: closing the mouth

Which choice(s) places the joints in the correct order from most stable to most mobile?

-Fibrous → Cartilaginous → Synovial -Suture → Syndesmosis → Symphysis

intracapsular ligaments

-Ligaments located inside the joint cavity and capsule. -may provide support and limit movement.

Synovial joints

-Synovial joints, characterized by a joint cavity containing synovial fluid, are the freely movable joints (diarthroses) -most common joints in the adult appendicular skeleton

Condyloid (or ellipsoid) joints

-are formed by an ovoid-shaped process (condyle) articulating with a shallow cavity (ellipsoid surface). -ex: radiocarpal joint (wrist)

Synovial bursae

-are small fibrous sacs lined with synovial membrane and containing synovial fluid. -placed to minimize friction -common in shoulder joint

ligaments

-bands of dense regular ct -joins bone to bone

Cartilaginous

-bones held together by cartilage -cartilage btw bones -lack a synovial cavity -provides little to no movement

Fibrous

-bones held together by dense connective tissue -lack catrilage and a synovial cavity

Fibrous joints

-connective tissue fibers, primarily collagen, connect bone -3 types of fibrous joints: sutures, syndesmoses, and gomphosis

joint capsules

-dense irregular ct -synovial membrane -includes joint cavity -synovial fluid

plane (gliding) joint

-describes joints that have no identifiable axis of rotation, and thus are categorized as "nonaxial". -ex: between articular facets on the vertebral arches, between most carpal and tarsal bones, and between ribs and vertebrae.

synovial membrane

-is the soft connective tissue lining of the joint capsule. -composed of loose connective tissue that includes blood and lymphatic vessels within a collagenous matrix. -secretes a small amount of synovial fluid into the joint cavity

Synovial fluid

-reduces friction, lubricates,damage due to friction and heat build-up is prevented -acts as a shock absorber, provides nutrients and O2 to chondrocytes in the articular cartilage, and removes waste from them.

Labrum

-reinforces joint, dense ct -common in knee joint

Stand in anatomical position. Your shoulder joints are in ________ degrees of flexion and your forearms are ________ so that the palms of your hands face ________.

0; supinated; anteriorly

What is the range of motion of the elbow if extension is 0degress and flexion is 145degrees?

145

Ball and socket joints have ________ degrees of freedom and can perform ________ movements (include any combination movements.)

3;7

Symphyses joint

A joint in which the bones are connected by fibrocartilage

flexion

Decreases the angle of a joint -lateral flexion: movement of the trunk in the frontal plane

special movements

Elevation, depression, protraction, retraction, inversion, eversion, dorsiflexion, plantar flexion, supination, pronation, and opposition.

Hyaline cartilage

Hyaline cartilage, with its densely packed collagen fibers, is smooth, firm, and flexible, and provides a low-friction surface

What components of sutures give this joint great strength?

Inter connecting tissue fibers and interlocking bones.

When a person does a push up, first pushing off the floor and fully straightening their elbow and the returning to the ground so that their chest touches the floor, what motions does the scapula go through?

Protraction and then retraction

Which of the following is not a function of synovial fluid?

Provide stem cells to repair articular cartilage

extracapsular ligaments

are made up of dense regular connective tissue

Joints can be classified in 2 ways. Structural or Functional

Structural-classify joints by the types of tissue connectin the bones Functional- classify joints by the amount of movement allowed

depression

a downward movement -ex: opening the mouth

Unlike other joint categories, all synovial joints have ________.

a joint capsule and lubricating fluid

Synchondroses

a joint in which the bones are united by hyaline cartilage

saddle joint

allow the same movements as condyloid joints, but are in a separate category due to the shapes of the articulating surfaces. -ex: (first) carpo-metacarpal joint of the thumb