Chapter 8: Articulations
The spherical end of one bone articulates with a cuplike socket of another bone
Ball and Socket
Movement in two planes (metacarpophalangeal joint, occipital condyles to atlas)
Biaxial Motion
A small, fluid-filled pocket that forms in a connective tissue. It contains synovial fluid and is lined by a synovial membrane.
Bursa
Located around most synovial joints, _____ reduce friction and act as shock absorbers.
Bursae
Often form where a tendon or ligament rubs against other tissues.
Bursae
Inflammation of the bursa
Bursitis
Held together by fibrous connective tissues such as ligaments but they also possess either hyaline cartilage or fibrocartilage.
Carilaginous joints
Draw around; conical shape or circular motion
Circumduction
Moving a limb in a circle creating a cone in space
Circumduction
Synovial joints are ....
Complex in sturcture The most numerous joint in the body Permit the greatest range of motion
Also known as ellipsoid joint
Condyloid Joints
Oval articular surface of one bone fits into a complementary depression in another
Condyloid Joints
Biaxial Joints
Condyloid Joints Saddle Joints
The edges of the bones are interlocked and bound together at the suture by ....
Dense fibrous connective tissue
Structure moves inferiorly
Depression
Freely moveable joints
Diarthrosis
All synovial joints are _________.
Diarthrotic
Complex in structure
Diarthrotic joints
________ _______ provide a wide range of motion as typical in the joints of our appendages.
Diarthrotic joints
Flexion at the ankle joint and elevation of the sole
Dorsiflexion
Structure moves superiorly
Elevation
A twist motion of the foot that turns the sole outward, elevating the lateral edge of the sole.
Eversion
Opposite of Inversion
Eversion
An angular movement within the anterior-posterior plane that increases the angle between the articulating elements.
Extension
Opposite of Flexion
Extension
Separate from the joint capsule and may pass outside (extracapsular) or inside (intracapsular) the joint capsule.
Extrinsic ligament
Commonly superficial to the joint capsule
Fat pads
Localized masses of adipose tissue covered by a layer of synovial membrane.
Fat pads
When the bones move, the ____ ____ fill in the spaces created as the joint cavity changes shape.
Fat pads
____ _____ protect the articular cartilages and act as packing material for the joint.
Fat pads
Thick outer layer continuous with the periosteum around the articulating bones. As a result, this adds strength and helps to stabilize the joint.
Fibrous Capsule
_______ ______ held together by fibrous connective tissues but lack cartilage and possess no cavity between the bones
Fibrous Joints
Angular movement within the anterior-posterior plane that reduces the angle between the articulating elements.
Flexion
The anterior surface of a limb turns away from the midline of the body
Lateral Rotation
Opposite to medial rotation
Lateral rotation
Support, strengthen, and reinforce synovial joints
Ligaments
Cartilaginous joints lack a ____ _____ and are either _________ or ________.
joint cavity; synarthrotic; amphiarthrotic
The anatomical structure of a joint determines the ____ and ______ of movement that may occur
type;amount
Even in large joints, such as the knee, the total quantity of synovial fluid is normally less than _ __.
3 mL
Angular movement within the lateral-medial plane that moves the body part away from the longitudinal axis
Abduction
In complex synovial joints, such as the knee, a variety of accessory structures provide support and additional stability.
Accesory structures of a typical synovial joint
Components of a Synovial joint:
Accessory Structures of a typical synovial joint Articular Cartilages Joint Capsule Joint Cavity Synovial Fluid
An angular movement within the lateral-medial plane that moves the body part toward the longitudinal axis
Adduction
Opposite of Abduction
Adduction
Only slight movement is permitted
Amphiarthrosis
A symphysis is considered an _________ ______.
Amphiarthrotic joint
An ________ ______ permits more movement than a ________ _____, but is much stronger than ________ ______.
Amphiarthrotic joint; Synarthrotic joints; Diarthrotic joints
The cartilaginous joint found between the ends of the first pair of ribs and the manubrium of the sternum
An example of Synchondrosis
the epiphyseal plate found holding the epiphysis of a long bone to the diaphysis
An example of Synchondrosis
Changing the angle between two bones
Angular
Inflammatory or degenerative disease of the joint where synovial membranes thicken (called pannus) and fluid production decreases resulting in friction and pain.
Arthritis
Composed of hyaline cartilage however these cartilages lack a perichondrium and the matrix contains more water than that of hyaline cartilage located elsewhere in the body.
Articular cartilages
Line the surfaces of the articulating bones
Articular cartilages
The _______ _______ provide a slick, smooth surface to the bones which reduces friction during movement.
Articular cartilages
Because the bones of the skeleton are relatively inflexible, movement can occur only at _________.
Articulations
Multi-axial Joints
Ball and Socket
__________ _________ are based on the range of motion allowed.
Functional classifications
Bones slide across the surface of one another
Gliding
A synarthrotic joint or "peg-in-socket" joint
Gomphosis
The ________ the range of motion at a joint, the ________ it becomes.
Greater; Weaker
A joint cannot be both _____ _____ and ____ _____.
Highly mobile; very strong
Cylindrical projection of one bone fits into a trough-shaped surface on another bone
Hinge Joints
Uniaxial Joints
Hinge Joints Pivot Joints
Angular movement where the body part is extended past the anatomical position
Hyperextension
Capsular Ligaments
Intrinsic ligament
Parallel bundles of fibers creating thickenings within the joint capsule.
Intrinsic ligament
A twist motion of the foot that turns the sole inward, elevating the medial edge of the sole
Inversion
Layers of dense fibrous connective tissues that enclose the synovial cavity to house the synovial fluid.
Joint Capsule
Articulations
Joints, where two bones interconnect
When part of an articular cartilage is compressed during movement, some of the synovial fluid is squeezed out of the cartilage and into the space between the opposing surfaces.
Lubrication
There are three primary functions of synovial fluid:
Lubrication Nutrient distribution Shock absorption
A Gomphosis joint is found on the ______ and ______ where the teeth are fixed securely in the sockets of the alveolar margins.
Maxillae; mandible
The anterior surface of a limb turns towards midline of the body; pigeon toe in the leg
Medial Rotation
A pad of fibrous cartilage situated between opposing bones within a synovial joint.
Meniscus
Movement in three planes (shoulder joint and hip joint)
Multi-Axial Motion
Linear movements where bones slide (vertebrocostal joints, sacroiliac joint, and intercarpal joints)
Non-axial motion
The synovial fluid in a joint must circulate continuously to provide nutrients and waste disposal for the chondrocytes of the articular cartilages.
Nutrient distribution
The movement of the thumb toward the surface of the palm or the pads of the other fingers
Opposition
The fibrous connective tissue between a tooth and its socket
Periodontal ligament
Rounded end of one bone protrudes into a sleeve or ring composed of bone or ligament
Pivot Joints
Non-Axial Joints
Plane Joints
Also known as gliding joints
Plane joints
Extend the ankle and elevates the heel
Plantar Flexion
Opposite to Dorsiflexion
Plantar Flexion
The shaft of the radius rotates, the distal epiphysis of the radius rolls across the anterior surface of the ulna so that the bones are crossing
Pronation
Moving a body part anteriorly in the horizontal plane
Protraction
The articulation between the two pubic bones
Pubic Symphysis
The amount of movement permitted
Range of Motion (ROM)
Articulations are often categorized by ______ __ _____ and ________ ________.
Range of motion; anatomical structure
Moving the body part posteriorly in the horizontal plane
Retraction
Opposite to protraction
Retraction
Turning movement of a bone around its own axis
Rotation
Articular surfaces have a concave area on one that fits with the convex area of the other
Saddle Joints
When a joint is subjected to compression, the synovial fluid provides a cushion against the shock.
Shock absorption
Stretching or tearing of a ligament across the joint capsule.
Sprain
________ _______ are based on the anatomical components that make up the joint.
Structural classifications
Menisci may ....
Subdivide a synovial cavity Channel the flow of synovial fluid Allow variations in the shapes of the articular surfaces
In anatomical position, the forearm is supinated with the radius and ulna lying parallel to each other and the palm facing anteriorly
Supination
A synarthrotic joint located only between the bones of the skull.
Sutures
Articulating bones are separated by a wedge or pad of fibrocartilage.
Symphysis
The articulation between the vertebrae where a thick pad of fibrocartilage forms the intervertebral disc is a common example of a ________.
Symphysis
No movement is permitted
Synarthrosis
At _________ _______, the bony edges are quite close together and may even interlock.
Synarthrotic joints
Simple in Structure
Synarthrotic joints Amphiarthrotic joints
A rigid, hyaline cartilage bridge unites the bones of a synchondrosis joint.
Synchondrosis
Bones are connected by an interosseous ligament and are amphiarthrotic.
Syndesmosis
A synarthrotic joint created when two bones fuse and the boundary between them disappears.
Synostosis
This fluid is largely derived from blood and has a clear, viscous, egg-white consistency.
Synovial Fluid
Inner soft tissue whose network of capillaries leak plasma from the bloodstream to produce the synovial fluid.
Synovial Membrane
Held together by fibrous connective tissues, hyaline cartilage and/or fibrocartilage, and possess a joint cavity.
Synovial joints
The most common example is the distal articulation between the tibia and fibula called the __________ ______.
Tibiofibular joint
Inflammation of the tendon
Tndonitis
Movement in one planes (finger joints, elbow, knee)
Uniaxial Motion
This thin layer of fluid markedly reduces friction between moving surfaces.
Weeping lubrication
Fibrous joints are either __________ or __________.
synathrotic; amphiarthrotic