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