Chapter 5 - Joints (ENS 303)
functions of joints
- movement - weight bearing - shock absorption - balance, mobility, and stability
synchondrosis
a union between two bones, formed either by hyaline cartilage or fibrocartilage
synovial fluid
a viscous fluid that fills the space in freely movable joints
pivot joint
a type of synovial joint that functions by having the surface of one bone spin within the ring-shaped surface of another bone
hinge joint
a type of uniaxial joint that allows movement around one axis (and within one plane)
gliding joint
a type of uniaxial synovial joint situated between two flat articular surfaces
symphysis
a union between two bones, formed by fibrocartilage
ligament
a band of connective tissue that connects bones togethe
ellipsoid joint
a biaxial synovial joint that consists of the oval-shaped end of one bone articulating with the elliptical basin of another bone
suture
a fibrous joint formed by a thin layer of dense connective tissue
plane
a flat, imaginary, two-dimensional surface in space
diarthrotic joint
a freely moveable, synovial joint
synovial joint
a joint containing a lubricating substance (synovial fluid) and lined with a synovial membrane or capsule
amphiarthrotic joint
a joint that allows a limited amount of movement
gomphosis
a joint that binds the teeth to bony sockets in the maxillary bone and mandible
axis
a line that runs perpendicular to a plane and is the pivot point around which motion occurs
saddle joint
a modified ellipsoid joint composed of convex and concave articulating surfaces that affords back-and-forth, as well as side-to-side, motion
labrum
a ring of cartilage that surrounds the acetabulum of the hip and glenoid fossa of the shoulder
articular disc
a ring-shaped piece of fibrocartilage found in many joints of your body, including the temporomandibular and sternoclavicular joints
bursa
a small, fluid-filled sack that reduces friction between two structures
syndesmosis
a strong, fibrous junction between two bones
ball and socket joint
a triaxial synovial joint where a spherical surface of one bone fits into the dish-shaped depression of another bone
hyaline cartilage
also known as articular cartilage, it is a type of cartilage found on many joint surfaces
cartilaginous joint
an amphiarthrotic joint that allows more movement between bones than a fibrous joint, but less than a synovial joint
fibrous joint
an articulation that has no synovial cavity and is bound together by dense fibrous connective tissue
frontal axis
an axis that passes anterior to posterior through the body
oblique axis
an axis that passes perpendicularly through an oblique plane
sagittal axis
an axis that runs medial to lateral through the body
transverse axis
an axis that runs superior to inferior through the body
synarthrotic joint
an immovable, fibrous joint
transverse (horizontal) plane
any horizontal plane that divides the body into superior and inferior sections
oblique plane
any plane that combines two or three cardinal planes
sagittal plane
any vertical plane that divides the body into left and right sections
frontal (coronal) plane
any vertical plane that divides the body or its parts into anterior and posterior sections
active transport
contractile tissue that stabilize a joint
anatomical position
erect posture with face forward, arms at sides, forearms supinated (so that palms of the hands face forward) and fingers and thumbs in extension
passive restraint
noncontractile tissues that stabilize a joint
myofascial unit
the combined muscular and fascial elements that comprise a muscle belly and its tendons
joint capsule
the envelope surrounding a synovial joint
synovial membrane
the internal layer of a joint capsule
degrees of freedom
the number of planes of movement allowed at a joint
joint mobility
the range of motion a joint can move through without limitation
cardinal plane
the three major planes that intersect at the center of the body
