Chapter 9- Joints Flashcards
What is another name for a joint?
Articulation
What is the science of joint structure, function, and dysfunction?
Arthrology
What is the study of musculoskeletal movement?
Kinesiology
What is an extended definition of kinesiology?
A branch of biomechanics, which deals with a broad variety of movements and mechanical processes
What is a joint name?
Typically derived from the names of the bones involved
How are joints classified?
Joints are classified according to the manner in which the bones are bound to each other
What are the four major joint categories?
- Bony joints
- Fibrous joints
- Cartilaginous joints
- Synovial joints
What’s another name for bony joints?
Synostosis
What are bony joints?
An immobile joint formed when the gap between two bones ossifies, and the bones become, in effect, a single bone.
What are some examples of bony joints?
- Left and right mandibular bones in infants
- Cranial sutures in elderly
- Attachment of first rib and sternum with old age
Where can bony joints occur?
Can occur in either fibrous or cartilaginous joint
What is another name for fibrous joints?
Synarthrosis
What are fibrous joints?
adjacent bones that are bound by collagen fibers that emerge from one bone and penetrate into the other
What are the three kinds of fibrous joints?
- Sutures
- Gomphoses
- Syndesmoses
What are sutures?
immobile or slightly mobile fibrous joints in which short collagen fibers bind the bones of the skull to each other
Sutures can be classified as?
- Serrate: interlocking wavy lines
- Coronal, sagittal, and lambdoid sutures
- Lap (squamous): overlapping beveled edges
- Temporal and parietal bones
- Plane (butt): straight, non-overlapping edges
- Palatine processes of the maxillae
What is gomphosis(fibrous joint)?
attachment of a tooth to its socket
What is holding a gomphosis is place?
- fibrous periodontal ligament
- Collagen fibers attach tooth to jawbone
- Allows the tooth to move a little under the stress of chewing
What is a syndesmosis?
a fibrous joint at which two bones are bound by long collagen fibers
Example of a very mobile syndesmosis?
Interosseus membrane joining radius to ulna allowing supination and pronation
Example of a less mobile syndesmosis?
Joint between tibia to fibula
What’s another name for cartiligenous joints?
Amphiarthrosis
What is a cartiligenous joint?
Two bones linked by cartilage
The two types of cartilaginous joints?
- Synchondroses
- Symphyses
What is a Synchrondrosis?
Bones joined by hyaline cartilage
- Temporary joints in the epiphyseal plates in children
- Bind epiphysis to diaphysis
- First rib attachment to sternum
- Other costal cartilages joined to sternum by synovial joints
What is a Symphysis?
two bones joined by fibrocartilage
- Pubic symphysis joins right and left pubic bones with interpubic disc
- Bodies of vertebrae joined by intervertebral discs
- Only slight movements between adjacent vertebrae
- Collective effect of all 23 discs gives spine considerable flexibility
What is another name for a synovial joint?
Diarthrosis
What are synovial joints?
joints in which two bones are separated by a joint cavity
- Most familiar type of joint
- Most are freely mobile
- Most structurally complex type of joint
- Most likely to develop painful dysfunction
- Most important joints for physical and occupational therapists, athletic coaches, nurses, and fitness trainers
- Their mobility makes them important to quality of life
What connective tissue coonects synovial joints? And how thick is the layer?
Articular cartilage—layer of hyaline cartilage that covers the facing surfaces of two bones
Usually 2 or 3 mm thick
What is synovial fluid? Why is it necessary?
Slippery lubricant in joint cavity
- Rich in albumin and hyaluronic acid
- Gives it a viscous, slippery texture like raw egg whites
- Nourishes articular cartilage and removes waste
- Makes movement of synovial joints almost friction free
What is a joint capsule(articular) for?
Connective tissue that encloses the cavity and retains the fluid
- Outer fibrous capsule: continuous with periosteum of adjoining bones
- Inner, cellular, synovial membrane: composed mainly of fibroblast-like cells that secrete synovial fluid and macrophages that remove debris from the joint cavity
What is a tendon?
strip of collagenous tissue attaching muscle to bone
What is a ligament?
strip of collagenous tissue attaching one bone to another
What is a bursa?
fibrous sac filled with synovial fluid, located between muscles, where tendons pass over bone, or between bone and skin
- Cushions muscles, helps tendons slide more easily over joints, modifies direction of tendon pull
What is a tendon sheath?
Elongated cylindrical bursa wrapped around a tendon
- In hand and foot
How many classes of synovial joints are there, and what are they?
- ball-and-socket
- condylar
- saddle
- plane
- hinge
- pivot
Explain a ball and socket joint?
- Smooth, hemispherical head fits within cup-like socket
- Only multiaxial joints in body
- Examples: shoulder, hip
Explain condylar (ellipsoid) joints?
- Oval convex surface of one bone fits into a complementary-shaped depression on the other
- Biaxial joints—movement in two planes
- Examples: radiocarpal joint, metacarpophalangeal joints
What are Saddle joints?
- Both bones have an articular surface that is shaped like a saddle, one concave, the other convex
- Biaxial joints
- Examples: trapeziometacarpal (opposable thumb), sternoclavicular joint
What are plane (gliding) joints?
- Flat articular surfaces, bones slide over each other
- Usually biaxial joints
- Examples: between carpal bones of wrist; between tarsal bones of ankle; also between articular processes of vertebrae
What is a hinge joint?
- One bone with convex surface fits into a concave depression of another bone
- Monoaxial joints—move freely in one plane
- Examples: elbow, knee, joints within fingers, toes
What is a pivot joint?
- A bone spins on its longitudinal axis
- Monoaxial joints
- Examples: atlantoaxial joint (C1 and C2), radioulnar joint at the elbow
What is Zero position?
- the position of a joint when a person is in the standard anatomical position
- Joint movements described as deviating from the zero position or returning to it
What is Flexion?
- movement that decreases joint angle
- FLEXING biceps
What is extension?
movement that straightens a joint and returns a body part to the zero position
What is Hyperextension?
- extension of a joint beyond the zero position
- Flexion and extension occur at nearly all diarthroses, hyperextension is limited to a few
What is Abduction?
- movement of a body part in the frontal plane away from the midline of the body
- Hyperabduction: raise arm over back or front of head
What is adduction?
- movement in the frontal plane back toward the midline
- Hyperadduction: crossing fingers, crossing ankles
What is elevation?
movement that raises a body part vertically in the frontal plane
What is depression?
movement that lowers a body part in the same plane
What is protraction?
the anterior movement of a body part in the transverse (horizontal) plane
What is retraction?
posterior movement
What is circumduction?
- one end of an appendage remains stationary while other end makes a circular motion
- Example: an artist circumducts upper limb when painting a circle on a canvas
What is rotation?
- movement in which a bone spins on its longitudinal axis
- Rotation of trunk, thigh, head, or arm
- Medial (internal) rotation turns the bone inward
- Lateral (external) rotation turns the bone outward
What is Supination?
What is Pronation?
- forearm movement that turns palm to face either posteriorly or downward
- Head of radius spins
- Radius crosses stationary ulna like an X
What is Dorsiflexion?
elevating toes as you do while swinging foot forward to take a step (heel strike)
What is Plantar flexion?
extending foot so that toes point downward as in standing on tiptoe (toe-off)
What is Inversion?
movement in which the soles are turned medially
What is Eversion?
movement in which the soles are turned laterally
