Joints Flashcards
joint (articulation)
site in which two or more bones or cartilages meet
How are joints classified?
anatomical or functional
How are joints anatomically classified?
synovial or solid
based on structure - materials that bind bones together, and presence/absence of joint cavity
How are joints functionally classified?
diarthrosis (freely movable), amphiarthrosis (slightly movable), or synarthrosis (immovable)
based on range of motion
Solid Joints
How are bones held together?
by connective tissue
Solid Joints
How are solid joints classified?
fibrous or cartilaginous
depending on type of connective tissue – dense connective tissue or cartilage
Solid Joints
What are the functional classifications of solid joints?
amphiarthrosis or synarthrosis
Solid Joints - Fibrous
How are bones linked together?
by dense connective tissue
Solid Joints - Fibrous
What are the 3 types of fibrous solid joints?
sutures
syndesmoses
gomphoses
Solid Joints - Fibrous
What are sutures?
joints formed between bones of skull
in early years of life, the bones are held together by thin layer of dense connective tissue that later will be replaced by bony tissue
Solid Joints - Fibrous
What are syndesmoses?
joint held together by a ligament
bones are connected to each other by membrane or ligament such as middle radioulnar joint
Solid Joints - Fibrous
What are gomphoses?
‘peg in socket’ joint
formed between roots of teeth and bony socket in maxilla and mandible by an intervening ligament - periodontal ligament (holds tooth in socket)
Solid Joints - Cartilaginous
How are bones held together?
by cartilage
Solid Joints - Cartilaginous
Describe the movement of cartilaginous joints.
limited movements
Solid Joints - Cartilaginous
What are the 2 types of cartilaginous solid joints?
synchondroses
symphases
Solid Joints - Cartilaginous
What are synchondroses joints?
bones are linked together by hyaline cartilage, such as growth plates of long bones
Solid Joints - Cartilaginous
What are symphases joints?
bones are connected by fibrocartilage
ie. pubic symphysis
Synovial Joints
What are synovial joints?
- presence of cavity between bones
- bones are held together by fibrous capsule
Synovial Joints
What are the basic features of all synovial joints?
- diarthrosis type
- joint capsule
- joint (articular) cavity
- synovial membrane (+ synovial cavity)
- synovial fluid
- articular cartilage
Synovial Joints
What is the functional classification of synovial joints?
diarthrosis
Synovial Joints
How are bones held together?
by fibrous capsule
Synovial Joints
What is the joint capsule?
fibrous sleeve-like structure that completely invests the joint and is supported by ligaments
Synovial Joints
What is the joint (articular) cavity?
space enclosed by joint fibrous capsule
Synovial Joints
What is the synovial membrane?
special layer of connective tissue that lines internal joint surfaces (except articular surfaces of bones)
Synovial Joints
What is the synovial cavity?
space enclosed by synovial membrane
Synovial Joints
What is synovial fluid?
Functions?
watery fluid secreted by synovial membrane contained within synovial cavity
- nourishes and lubricates articular cartilage
- facilitates joint movement
Synovial Joints
What is articular cartilage?
thin layer of hyaline cartilage or fibrocartilage that covers articular surfaces of bone
Synovial Joints
What are the 4 types of synovial joints?
- non-axial
- uniaxial (or monoaxial)
- biaxial
- multiaxial
Synovial Joints - Non-axial
What is the 1 type of non-axial joint?
What function does it perform?
plane (planar or gliding): articular surfaces are almost flat
performs sliding or gliding movements in different directions (ie. intercarpal joints)
Synovial Joints - Monoaxial/Uniaxial
What are the 2 types of monoaxial/uniaxial joints?
hinge
pivot
Synovial Joints - Monoaxial/Uniaxial
What are hinge joints?
What function does it perform?
convex pulley shaped articular surface meets a concave articular surface
specifically designed to perform flexion and extension movements (ie. elbow joint)
Synovial Joints - Monoaxial/Uniaxial
What are pivot joints?
What function does it perform?
round articular surface fits a relatively shallow concave articular surface
only designed for rotational movements (ie. proximal radioulnar joint)
Synovial Joints - Biaxial
What are the 2 types of biaxial joints?
ellipsoid/condyloid
saddle
Synovial Joints - Biaxial
What are ellipsoid/condyloid joints?
What function does it perform?
oval convex articular surface of one bone meets the oval concave articular surface of another bone
for flexion, extension, abduction, adduction, or circumduction (ie. metacarpophalangeal joints)
Synovial Joints - Biaxial
What are saddle joints?
What function does it perform?
articular surfaces of both bones resemble a saddle
for flexion, extension, abduction, adduction, or circumduction (ie. first carpometacarpal joint)
Synovial Joints - Multiaxial
What is the 1 type of multiaxial joint?
What function does it perform?
ball and socket: spherical articular surface of one bone fits with cup-shaped articular surface of other bone
for flexion, extension, abduction, adduction, medial and lateral rotations, or circumduction (ie. shoulder joints)
Structures Associated with Synovial Joints
What are the 5 structures associated with synovial joints?
- ligament
- bursae
- menisci
- labrums
- intra-articular discs
Structures Associated with Synovial Joints
What do structures associated with synovial joints do?
some structures associated with different types of synovial joints function to facilitate movements of soft tissues surrounding the joints, or to support joints
Structures Associated with Synovial Joints
What are ligaments?
thick bands of dense connective tissue that join the bones to each other
Structures Associated with Synovial Joints
What are the two types of ligaments?
extrinsic ligament - separate
intrinsic ligament - thickened part of fibrous capsule
Structures Associated with Synovial Joints
What are bursae?
small sacs of connective tissue separating the moving structures around the joints
(ie. bursae between skin and joint capsule, or between muscle and joint capsule)
Structures Associated with Synovial Joints
What are bursae lined by?
lined by synovial membrane, and filled with synovial fluid
Structures Associated with Synovial Joints
What are menisci?
incomplete fibrocartilage rings attached to articular surfaces of tibia to increase joint congruency
Structures Associated with Synovial Joints
What are labrums?
fibrocartilage rings attached to circumference of glenoid cavity and acetabulum to enhance their depth
Structures Associated with Synovial Joints
What are intra-articular discs?
cushions of fibrocartilage found within joints to absorb shocks and/or increase congruency
Joints of the Trunk - VERTEBRAL COLUMN
What are the 3 parts where typical vertebrae articulate with each other?
- synovial plane joints between superior and inferior articular processes on each side, zygapophyseal (facet) joints
- symphysis joints between vertebral bodies via intervertebral discs
Joints of the Trunk - VERTEBRAL COLUMN
What is an intervertebral disc composed of?
composed of nucleus pulposus (centrally located gelatinous substance) surrounded by concentric layers of dense connective tissue (annulzus fibrosus)
Joints of the Trunk - VERTEBRAL COLUMN
What is the atlanto-axial joint?
synovial pivot joint between anterior arch of atlas (CI) and odontoid process of axis (CII)
Joints of the Trunk - VERTEBRAL COLUMN
What is the atlanto-occipital joint?
synovial condyloid joints between atlas (CI) and condyles of occipital bone
Joints of the Trunk - VERTEBRAL COLUMN
What are the 6 ligaments that support vertebral column?
- anterior longitudinal ligament
- posterior longitudinal ligament
- flava ligaments
- interspinous ligaments
- supraspinous ligaments
- nuchal ligament
Joints of the Trunk - VERTEBRAL COLUMN
Where is the anterior longitudinal ligament?
stretches along anterior surfaces of vertebral bodies
Joints of the Trunk - VERTEBRAL COLUMN
Where is the posterior longitudinal ligament?
stretches along posterior surfaces of vertebral bodies
Joints of the Trunk - VERTEBRAL COLUMN
What do flava ligaments do?
join laminae of adjacent vertebrae to each other