Arthrology Flashcards
Define
Arthrology
Study of joints
Define
articulation
Joint between bone or cartilage
Function
joints
Can confer stability or motion between structures
How are joints classified?
Degree of motion
Types of tissues in articulation
Types of joint classifications by movement
Synarthroses, amphiarthroses, diarthroses
What is synarthroses
Mostly fibrous, no/limited movement
What is amphiarthroses?
Mostly cartilaginous
Slightly moveable
What is diarthroses?
Synovial, highly moveable
Example of synarthroses
Sutures (skull)
Define
synostosis
Fusion of joint, ultimate fate of most synarthroses/amphiarthroses
Where does synostosis occur?
- between sutures in adulthood
- some symphyses by adulthood (IVD & pubic symphysis are pathological)
- all synchondroses
What is craniosynostosis?
- Fusion of cranial sutures before birth or during early childhood, before the completion of bone skull growth
- constricts brain growth in direction of fusion and flexibility of plate-like cranial bones, resulting in misshapen cranium
Examples of amphiarthroses
- syndesmoses
- symphyses (eg. IVD, pubic symphysis)
Examples of diarthroses (synovial)
- knee
- shoulder
- hip
What surrounds the articulation of synovial joints?
Synovial membrane
Structure of synovial joint
- 2 articulating bones with articular cartilage
- surrounded by synovial membrane, filled with synovial fluid
What is the difference between synarthroses and amphiarthroses?
synarthroses - no movement, mostly fibrous
amphiarthroses - some movement, mostly cartilaginous
When is synostosis pathological?
- fusion of IVD and/or pubic symphysis (in adults)
- craniosynostosis (early fusion of cranial sutures)
Joint classifications by tissue type
Fibrous, cartilaginous, synovial
Define
fibrous joint
No/limited movement, bone-CT-bone
Define
cartilaginous joint
Slightly moveable, bone-cartilage-bone
Define
synovial joint
Highly moveable, bone-cavitated CT (filled w synovial fluid)-cartilage-bone
Where are fibrous suture joints located?
Confined to cranium (sutures)
Function of sutures
Shock absorption, stability
Location of fibrous gomphosis joints
Anchoring tooth in socket
What anchors the tooth in its socket?
Cartilaginous periodontal ligament
Structure of gomphosis
Bone-cartilaginous periodontal ligament-dental cementum
Types of fibrous joints
Suture, gomphosis, syndesmosis
Define
syndesmosis
2 bones bound together by cartilaginous interosseous ligament
Examples of syndesmosis ligaments
- Radioulnar, tibiofibular interosseus ligaments
- ant/post. longitudinal ligaments of spine (vertebral bodies)
- ligamentum flavum (laminae)
Function of syndesmosis
Dynamic stabilization, resist forces that separate bones
Does synostosis result in intellectual impairment?
no functional impairment, only affects shape
what gives ligaments the ability to stretch?
elastin
what kind of amphiarthrosis is defined by bones connected by a fibrous ligament?
syndesmoses
what type of joint would confer the most motion?
diarthroses
what type of joint would confer the most stability?
synarthroses
what makes up collagenous sutural ligaments?
sharpey’s fibers
between periosteum of 2 bones
Types of cartilaginous joints
Synchondrosis
Symphyses
Synchondrosis structure
Bone - hyaline growth cartilage - bone
Locations of synchondrosis
Epiphyseal growth plates
Basisphenoid synchondrosis
Symphysis structure
Bone - hyaline cartilage - fibrocartilaginous disc - hyaline cartilage - bone
Function of symphyses
Stability, resist forces at weight bearing joints
Locations of symphyses
Manubriosternal
Xiphisternal
Intervertebral discs
Pubic symphysis
Mandibular symphysis
Symphyses are confined to the ____
Axial skeleton
Types of supportive ligaments
Extrinsic
Intrinsic
Intracapsular
Extrinsic ligaments
Outside of fibrous joint capsule
Eg. LCL of knee
Intrinsic ligaments
Within or on surface of fibrous joint capsule
Eg. Ischiofemoral/pubofemoral ligaments of hip
Intracapsular ligaments
Inside synovial cavity
Eg. ACL/PCL of knee, ligamentum teres of hip
Fat pads
Areas of adipose tissue within the joint capsule to cushion the articulation
Fibrocartilaginous discs
Menisci
Disperse weights and remove friction during movement
Diarthroses classification by shape of joint surfaces
Plane
Ginglymus (hinge)
Trochoid (pivot)
Bicondyloid
Ellipsoid (condyloid)
Sellar (saddle)
Spheroidal (ball & socket)
Plane synovial joint
Translates motion across flat joint surfaces in apposition
Eg. Zygapophyseal joints (facet joints)
Hinge joint (ginglymus)
Uniaxial joint allowing motion with 1 degree of freedom (only flexion & extension)
Eg. Elbow joint
Pivot joint (trochoid)
Uniaxial
Rotation of bone around single axis
Eg. Medial atlantoaxial joint, radioulnar joint
Bicondyloid joints
Mostly uniaxial with some rotatory movement
2 convex condyles articulating with 2 concave joint surfaces
Eg. Femoral condyles and tibial plateau, temperomandibular joint, atlantooccipital joints
Ellipsoid (condyloid) joints
Biaxial
Oval ellipsoid convex surface articulates with oval ellipsoid concave surface
Eg. Distal radius with scaphoid & lunate in wrist
Sellar (saddle) joints
Multiaxial
2 concave-convex (saddle-shaped) surfaces articulating with each other
Eg. Pollical carpometacarpal joint (thumb)
Ball & socket joints (spheroidal)
Multiaxial
Three degrees of freedom of motion
Eg. Glenohumeral joint, hip joint
