L5: Joints Pt. 1 Flashcards
(428 cards)
1
Q
The joints of the skeletal system contribute to homeostasis by
A
holding bones together in ways that allow for movement and flexibility.
2
Q
What does the human skeleton need to do?
A
Move
3
Q
Why can’t bones bend without being damaged?
A
They are too rigid
4
Q
What holds bones together at points of contact?
A
Flexible connective tissues
5
Q
What are points of contact where bones are held together called?
A
Joints
6
Q
What do joints permit in most cases?
A
Some degree of movement
7
Q
What should one think about regarding the bones of the body moving against one another?
A
The amazing range of motion and the complexity of coordinated movements
8
Q
What are examples of complex movements that occur as bones move?
A
Hitting a golf ball or playing a piano
9
Q
How do the movements of the human body compare to machines?
A
They are far more complex than those of almost any machine
10
Q
How often are many joint actions repeated?
A
Daily
11
Q
During what stages of life do joint actions produce continuous work?
A
From childhood, into adolescence, and throughout adult lives
12
Q
What is another name for a joint?
A
Articulation or arthrosis
13
Q
What is a joint?
A
A point of contact between two bones, between bone and cartilage, or between bone and teeth
14
Q
What is the scientific study of joints called?
A
Arthrology
15
Q
What is the study of motion of the human body called?
A
Kinesiology
16
Q
What are the three principal types of joints based on the type of material or manner in which articulating bones are united?
A
Fibrous, cartilaginous, and synovial
17
Q
What are fibrous joints united by?
A
Dense irregular connective tissue (mainly collagen fibers)
18
Q
How does the degree of movement in fibrous joints vary?
A
From immovable to slightly movable
19
Q
What does the degree of movement in fibrous joints depend on?
A
The length of the collagen fibers that join the articulating bones
20
Q
What are the two subtypes of fibrous joints?
A
Sutures and syndesmoses
21
Q
What characterizes cartilaginous joints?
A
The presence of a solid piece of hyaline cartilage or fibrous cartilage that unites the articulating bones
22
Q
How does the degree of movement in cartilaginous joints vary?
A
From immovable to slightly movable
23
Q
What are the two subtypes of cartilaginous joints?
A
Synchondroses and symphyses
24
Q
What type of joints make up most of the joints in the body?
A
Synovial joints
25
What characterizes synovial joints?
A two-layered articular capsule that unites the articulating bones and surrounds a lubricated space called an articular cavity
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What supplies the lubrication in synovial joints?
The inner layer of the articular capsule
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How does the degree of movement in synovial joints vary?
From slightly movable to freely movable
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What are the various types of synovial joints?
Plane, hinge, pivot, ellipsoid, saddle, and ball-and-socket
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How are the joints of the body presented in the following sections?
According to their structural classification
30
What will also be outlined while examining the structure of each type of joint?
Its various degrees of movement
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In fibrous joints, how are articulating bones held together?
By dense irregular connective tissue
32
How much movement do fibrous joints permit?
Little or no movement
33
What are the two types of fibrous joints?
Sutures and syndesmoses
34
What is a suture?
A fibrous joint composed of a thin layer of dense irregular connective tissue
35
Where do sutures occur?
Only between bones of the skull
36
What is an example of a suture?
The coronal suture between the parietal and frontal bones
37
What do the irregular, interlocking edges of sutures provide?
Added strength and a decreased chance of fracturing
38
When do sutures form?
As the numerous bones of the skull come in contact during development
39
How movable are sutures in older individuals?
They are immovable
40
How movable are sutures in infants and children?
They are slightly movable
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What roles do sutures play?
They act as sites of growth and help in shock absorption in the skull
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What happens to some sutures in adulthood?
They are replaced by bone
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What is a synostosis?
A bony joint where there is a complete fusion of two separate bones into one
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What is an example of a synostosis?
The frontal bone, which grows in halves that join together across a suture line
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By what age is the frontal bone usually completely fused?
By age 6
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What is a frontal (metopic) suture?
A suture that persists beyond age 6
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How movable is a frontal (metopic) suture?
It is immovable
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What is a syndesmosis?
A fibrous joint in which there is generally a greater distance between the articulating surfaces and more dense irregular connective tissue than in a suture
49
How many types of syndesmoses are there?
Three
50
How is the fibrous connective tissue arranged in the first two types of syndesmoses?
As either an interosseous ligament or an interosseous membrane
51
How much movement do interosseous ligaments and interosseous membranes permit?
Limited movement
52
What is an example of an interosseous ligament?
The anterior tibiofibular ligament
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What does the anterior tibiofibular ligament connect?
The distal tibia and fibula at the distal tibiofibular joint
54
What is an interosseous membrane?
A substantial sheet of dense irregular connective tissue that binds neighboring long bones and permits slight movement
55
Where do interosseous membranes occur?
Between the radius and ulna in the forearm and between the tibia and fibula in the leg
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What roles do interosseous membranes play?
They help hold adjacent long bones together, define the range of motion between neighboring bones, and provide an increased attachment surface for muscles that produce movements of the ankle, wrist, and digits of the hand and foot
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What is the third type of syndesmosis?
A gomphosis or dentoalveolar joint
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What is a gomphosis?
A joint in which a cone-shaped peg fits into a cavity with a small amount of dense irregular connective tissue
59
What are the only examples of gomphoses in the human body?
The articulations between the roots of the teeth and their dental alveoli in the alveolar process in the maxillae and mandible
60
What is the dense irregular connective tissue between a tooth and its dental alveolus?
The thin periodontal ligament
61
What does a healthy gomphosis permit?
Minute shock-absorbing movements
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What is inflammation and degeneration of the gums, periodontal ligament, and bone called?
Periodontal disease
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At a ___ the bones are held together by dense irregular connective tissue.
fibrous joint
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How much movement does a cartilaginous joint allow?
Little or no movement
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How are the articulating bones in a cartilaginous joint connected?
By either a solid piece of hyaline cartilage or fibrous cartilage
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What are the two types of cartilaginous joints?
Synchondroses and symphyses
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What is a synchondrosis?
A cartilaginous joint in which the connecting material is a solid piece of cartilage that allows little or no movement
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How are the articulating bones in a synchondrosis connected?
By hyaline cartilage or fibrous cartilage
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What is an example of a synchondrosis?
The joint between the first rib and the manubrium of the sternum
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What is another type of synchondrosis?
Epiphyseal cartilage
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What are epiphyseal cartilages?
Hyaline cartilage growth centers during endochondral bone formation, not joints associated with movements
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What is an example of epiphyseal cartilage?
The epiphyseal (growth) plate that connects the epiphysis and diaphysis of a growing long bone
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What does the presence of an epiphyseal plate in a radiograph indicate?
That a person still has the potential for some degree of growth to occur
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What can damage to the cartilage of a synchondrosis in the epiphyseal plate cause?
It can affect further growth of the bone, leading to abbreviated development and a bone of shortened length
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What type of joint is epiphyseal cartilage?
An immovable joint
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What happens when bone elongation ceases?
Bone replaces the hyaline cartilage and becomes a synostosis, a bony joint
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What is a symphysis?
A cartilaginous joint in which the ends of the articulating bones are covered with hyaline cartilage, but a broad, flat disc of fibrous cartilage connects the bones
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Where do all symphyses occur?
In the midline of the body
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What is an example of a symphysis?
The pubic symphysis between the anterior surfaces of the hip bones
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Where else is a symphysis found?
At the junction of the manubrium and body of the sternum and at the intervertebral joints between the bodies of vertebrae
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What is a portion of the intervertebral disc composed of?
Fibrous cartilage
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What type of joint is a symphysis?
A slightly movable joint
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At a ____ the bones are held together by cartilage.
cartilaginous joint
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What is the unique characteristic of a synovial joint?
The presence of a space between the articulating bones called an articular cavity
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What surrounds the articular cavity in a synovial joint?
An articular capsule that attaches the articulating bones and contains a lubricating fluid
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What does the presence of an articular cavity permit?
A wide range of movements from slightly movable to freely movable
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What is an example of synovial joints with very limited movements?
The synovial joints between some carpal bones
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Which synovial joint can move freely in all directions?
The shoulder joint
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What is the articular cartilage?
A layer of hyaline cartilage that covers the surfaces of the bones within a synovial joint
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What does the articular cartilage reduce?
Friction between bones in the joint during movement
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What does the articular cartilage help absorb?
Shock
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What is an alternative to partial or total knee replacement for minor damage to articular cartilage in the knee joint?
Autologous chondrocyte implantation (ACI)
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What type of damage is ACI used for?
Cartilage damage due to acute or repetitive trauma, not arthritis
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Where are healthy chondrocytes taken from in the procedure?
An area of the femoral condyle that is not weight-bearing
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How long are chondrocytes cultured in the laboratory?
6 to 8 weeks
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How many cells are generated during the culture process?
Between 5 million and 10 million cells
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What is done to the damaged area before implantation?
Dead cartilage is removed from the defect, which is covered by a piece of periosteum
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Where are the cultured chondrocytes injected after preparation?
Under the periosteum
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How long does it take for the patient to put full weight on the knee after ACI?
About 10 to 12 weeks
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What surrounds a synovial joint, encloses the articular cavity, and unites the articulating bones?
A sleevelike articular capsule or joint capsule
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What is the articular capsule composed of?
Two layers: an outer fibrous layer and an inner synovial membrane
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What does the fibrous layer of the articular capsule usually consist of?
Dense irregular connective tissue that attaches to the periosteum of the articulating bones
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What is the fibrous layer literally a thickened continuation of?
The periosteum between the bones
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What does the flexibility of the fibrous layer permit?
Considerable movement at a joint
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What does the fibrous layer's great tensile strength help prevent?
The bones from dislocating (the displacement of a bone from its joint)
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What are the fibers of some fibrous membranes arranged as?
Parallel bundles of fibrous connective tissue that are highly adapted for resisting strains
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What are these parallel bundles of fibers called?
Ligaments
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What is the principal mechanical factor that holds bones close together in a synovial joint?
The strength of ligaments
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What is the inner layer of the articular capsule called?
The synovial membrane
110
What is the synovial membrane composed of?
Areolar connective tissue with collagen and elastic fibers
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What does the synovial membrane often include at many synovial joints?
Accumulations of adipose tissue, called articular fat pads
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What is an example of an articular fat pad?
The infrapatellar fat pad in the knee
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What does a "double-jointed" person have greater flexibility in?
Their articular capsules and ligaments
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What does the greater flexibility in a double-jointed person allow them to do?
Increase range of motion, allowing activities such as touching their thumbs to their wrists and putting their ankles or elbows behind their necks
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What is the downside of having flexible joints?
They are less structurally stable and more easily dislocated
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The distinguishing feature of a synovial joint is the
articular cavity between the articulating bones
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What does the synovial membrane secrete?
Synovial fluid
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What is synovial fluid described as?
A viscous (gel-like), clear or pale yellow fluid
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What is synovial fluid named for?
Its similarity in appearance and consistency to uncooked egg white
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What does synovial fluid consist of?
Hyaluronic acid secreted by synovial cells (synoviocytes) in the synovial membrane and interstitial fluid filtered from blood plasma
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Where does synovial fluid form a thin film?
Over the surfaces within the articular capsule
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What are the functions of synovial fluid?
Reducing friction by lubricating the joint, absorbing shocks, and supplying oxygen and nutrients to and removing carbon dioxide and metabolic wastes from the chondrocytes within articular cartilage
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Why does cartilage not have blood vessels?
Because cartilage is an avascular tissue
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What does synovial fluid also contain that helps with joint maintenance?
Phagocytic cells that remove microbes and debris from normal wear and tear in the joint
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What happens to the viscosity of synovial fluid when a synovial joint is immobile?
The fluid becomes quite viscous
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What happens to the viscosity of synovial fluid when joint movement increases?
The fluid becomes less viscous
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What is one of the benefits of warming up before exercise?
It stimulates the production and secretion of synovial fluid
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What happens to the joints when there is more synovial fluid?
There is less strain on the joints during exercise
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What are the cracking or popping sounds in certain joints caused by?
The formation of bubbles in the articular cavity as gases come out of solution
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What makes the popping sound in joints?
The formation of the bubble
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Why can't you usually immediately pop your knuckles again after cracking them?
It takes time for the gases to re-accumulate
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What are accessory ligaments in synovial joints called?
Extracapsular ligaments and intracapsular ligaments
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Where do extracapsular ligaments lie?
Outside the articular capsule
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What is an example of an extracapsular ligament in the knee joint?
The fibular collateral ligament or thickening of the external region of the articular capsule, such as the tibial collateral ligament
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Where do intracapsular ligaments occur?
Within the articular capsule but are excluded from the articular cavity by folds of the synovial membrane
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What are examples of intracapsular ligaments in the knee joint?
The anterior and posterior cruciate ligaments
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What are articular discs or menisci?
Crescent-shaped pads of fibrous cartilage lying between the articular surfaces of the bones and attached to the fibrous capsule
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What are the menisci in the knee joint called?
The lateral and medial menisci
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What do the menisci do in the knee joint?
They bind strongly to the inside of the fibrous layer and usually subdivide the synovial cavity into two spaces
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What are the functions of the menisci?
(1) Shock absorption; (2) A better fit between articulating bony surfaces; (3) Providing adaptable surfaces for combined movements; (4) Weight distribution over a greater contact surface; (5) Distribution of synovial fluid across the articular surfaces of the joint
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What is a labrum?
A ring-like fibrous cartilage lip that extends from the circumference of the joint socket
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Where is the labrum prominent?
In the ball-and-socket joints of the shoulder and hip
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What does the labrum help with in ball-and-socket joints?
It helps deepen the joint socket and increases the area of contact between the socket and the ball-like surface of the head of the humerus at the shoulder joint or the femur at the hip joint
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What nerves supply a joint?
The nerves that supply the joint are the same as those that supply the skeletal muscles that move the joint
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Where are nerve endings distributed in synovial joints?
The nerve endings are distributed to the articular capsule and associated ligaments
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What do some of the nerve endings in synovial joints convey?
Some nerve endings convey information about pain from the joint to the spinal cord and brain for processing
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What do other nerve endings in synovial joints respond to?
Other nerve endings respond to the degree of movement and stretch at a joint
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How do the spinal cord and brain respond to movement and stretch at a joint?
The spinal cord and brain send impulses through different nerves to the muscles to adjust body movements
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What is the vascularization status of the cartilaginous components of synovial joints?
Many of the cartilaginous components of synovial joints are avascular
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How do arteries supply oxygen and nutrients to synovial joints?
Arteries in the vicinity send out numerous branches that penetrate the ligaments and articular capsule to deliver oxygen and nutrients
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How are carbon dioxide and wastes removed from synovial joints?
Veins remove carbon dioxide and wastes from the joints
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Where do the arterial branches from different arteries merge before penetrating the articular capsule?
The arterial branches from several different arteries typically merge around a joint before penetrating the articular capsule
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How do chondrocytes in the articular cartilage receive oxygen and nutrients?
The chondrocytes in the articular cartilage of a synovial joint receive oxygen and nutrients from synovial fluid derived from blood
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How are all other joint tissues supplied with oxygen and nutrients?
All other joint tissues are supplied directly by capillaries
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How do chondrocytes pass carbon dioxide and wastes from articular cartilage?
Carbon dioxide and wastes pass from chondrocytes of articular cartilage into synovial fluid and then into veins
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How do carbon dioxide and wastes from all other joint structures pass?
Carbon dioxide and wastes from all other joint structures pass directly into veins
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What do the various movements of the body create between moving parts?
The various movements of the body create friction between moving parts
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What are saclike structures called that alleviate friction in some joints?
The saclike structures called bursae alleviate friction in some joints
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Where are bursae strategically situated to alleviate friction?
Bursae are strategically situated to alleviate friction in joints such as the shoulder and knee joints
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Are bursae strictly part of synovial joints?
Bursae are not strictly part of synovial joints
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What do bursae resemble?
Bursae resemble articular capsules
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What are the walls of bursae made of?
The walls of bursae consist of an outer fibrous layer of thin, dense irregular connective tissue lined by a synovial membrane
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What is bursae filled with?
Bursae are filled with a small amount of fluid that is similar to synovial fluid
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Where can bursae be located?
Bursae can be located between the skin and bones, tendons and bones, muscles and bones, or ligaments and bones
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What do fluid-filled bursal sacs cushion?
The fluid-filled bursal sacs cushion the movement between body parts against one another
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What structures also reduce friction around joints?
Tendon sheaths also reduce friction around joints
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What are tendon sheaths also known as?
Tendon sheaths are also known as synovial sheaths
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What do tendon sheaths resemble?
Tendon sheaths are tube-like bursae
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What do tendon sheaths wrap around?
Tendon sheaths wrap around certain tendons that experience considerable friction
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What do tendon sheaths pass through?
Tendon sheaths pass through tunnels formed by connective tissue and bone
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What is the inner layer of a tendon sheath called?
The inner layer of a tendon sheath is called the visceral layer
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What is the outer layer of a tendon sheath called?
The outer layer of a tendon sheath is called the parietal layer
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What is between the layers of a tendon sheath?
Between the layers of a tendon sheath is a cavity that contains a film of synovial fluid
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What does a tendon sheath protect?
A tendon sheath protects all sides of a tendon from friction as the tendon slides back and forth
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Where are tendon sheaths found?
Tendon sheaths are found where tendons pass through articular cavities, such as the tendon of the biceps brachii muscle at the shoulder joint
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Where else are tendon sheaths found?
Tendon sheaths are also found at the wrist and ankle, where many tendons come together in a confined space
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Where else are tendon sheaths found in the body?
Tendon sheaths are found in the digits of the hand and toes, where there is a great deal of movement
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What is the tearing of menisci in the knee commonly called?
The tearing of menisci in the knee is commonly called torn cartilage
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Who does the tearing of menisci often occur among?
The tearing of menisci often occurs among athletes
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What will happen to damaged cartilage if it is not treated surgically?
Damaged cartilage will begin to wear and may cause arthritis to develop unless treated surgically
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What procedure was used years ago to treat torn cartilage?
The procedure used years ago to treat torn cartilage was called a meniscectomy
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What was the problem with the procedure used years ago to treat torn cartilage?
The problem was that over time the articular cartilage was worn away more quickly
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What is the current procedure performed for torn cartilage?
The current procedure performed is a partial meniscectomy
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What is removed in a partial meniscectomy?
In a partial meniscectomy, only the torn segment of the meniscus is removed
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What procedure may assist surgical repair of torn cartilage?
Arthroscopy may assist surgical repair of torn cartilage
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What is arthroscopy?
Arthroscopy is a minimally invasive procedure that involves examination of the interior of a joint
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What joint is usually examined with an arthroscope?
The knee is usually examined with an arthroscope
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What is an arthroscope?
An arthroscope is a lighted, pencil-thin fiber-optic camera used for visualizing the nature and extent of damage
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What is arthroscopy also used for?
Arthroscopy is also used to monitor the progression of disease and the effects of therapy
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What can the insertion of surgical instruments through other incisions do?
The insertion of surgical instruments through other incisions can remove torn cartilage, repair damaged cruciate ligaments in the knee, obtain tissue samples for analysis, and perform surgery on other joints
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What joints can surgery be performed on with arthroscopy?
Surgery can be performed on joints such as the shoulder, elbow, ankle, and wrist
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What is an acute or chronic inflammation of a bursa called?
An acute or chronic inflammation of a bursa is called bursitis
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What usually causes bursitis?
Irritation from repeated, excessive exertion of a joint usually causes bursitis
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What other factors can cause bursitis?
Bursitis can also be caused by trauma, by an acute or chronic infection (including syphilis and tuberculosis), or by rheumatoid arthritis
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What are the symptoms of bursitis?
The symptoms of bursitis include pain, swelling, tenderness, and limited movement
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What may the treatment for bursitis include?
The treatment for bursitis may include oral anti-inflammatory agents and injections of cortisol-like steroids
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Who uses specific terminology to designate the movements that can occur at synovial joints?
Anatomists, physical therapists, and kinesiologists use specific terminology to designate the movements that can occur at synovial joints
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What do anatomists, physical therapists, and kinesiologists look for ways to improve?
They look for ways to improve the efficiency and performance of the human body at work, in sports, and in daily activities
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What do the precise terms used by these professionals indicate?
The precise terms may indicate the form of motion, the direction of movement, or the relationship of one body part to another during movement
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How are movements at synovial joints grouped?
Movements at synovial joints are grouped into four main categories: (1) gliding, (2) angular movements, (3) rotation, and (4) special movements
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Where do special movements occur?
Special movements occur only at certain joints
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What is gliding?
Gliding is a simple movement in which nearly flat bone surfaces move back-and-forth and from side-to-side with respect to one another
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Is there any significant alteration of the angle between the bones during gliding?
No, there is no significant alteration of the angle between the bones
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What limits the range of gliding movements?
Gliding movements are limited in range due to the structure of the articular capsule and associated ligaments and bones
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Can gliding movements be combined with any other movements?
Yes, these sliding movements can also be combined with rotation
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What are examples of articulations where gliding movements occur?
The intercarpal and intertarsal joints are examples of articulations where gliding movements occur
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consist of side- to- side and back- and- forth motions.
Gliding movements
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What is angular movement?
In angular movements, there is an increase or a decrease in the angle between articulating bones
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What are the major angular movements?
The major angular movements are flexion, extension, lateral flexion, abduction, adduction, and circumduction
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What are flexion and extension?
Flexion and extension are opposite movements.
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What happens during flexion?
In flexion, there is a decrease in the angle between articulating bones.
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What happens during extension?
In extension, there is an increase in the angle between articulating bones, often to restore a part of the body to the anatomical position after it has been flexed.
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What plane do flexion and extension usually occur along?
Both movements usually occur along the sagittal plane.
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What type of movement is flexion at ball-and-socket joints?
At ball-and-socket joints, flexion is an anterior movement.
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What type of movement is extension at ball-and-socket joints?
At ball-and-socket joints, extension is a posterior movement.
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What are some examples of flexion?
• Bending the head toward the chest at the atlanto- occipital joints between the atlas (the first vertebra) and the occipital bone of the skull, and at the cervical intervertebral joints between the cervical vertebrae
• Bending the trunk forward at the intervertebral joints, as in doing a crunch with your abdominal muscles
• Moving the humerus forward at the shoulder joint, as in swinging the arms forward while walking
• Moving the forearm toward the arm at the elbow joint between the humerus, ulna, and radius, as in bending your elbow
• Moving the palm toward the forearm at the wrist or radiocarpal joint between the radius and carpals, as in the upward movement when doing wrist curls
• Bending the digits of the hand at the interphalangeal joints between phalanges, as in clenching your fingers to make a fist
• Moving the femur forward at the hip joint between the femur and hip bone, as in walking
• Moving the heel toward the buttock at the tibiofemoral joint between the tibia, femur, and patella, as occurs when bending the knee
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Where does flexion of the thumb occur?
Flexion of the thumb involves movement of the thumb medially across the palm at the carpometacarpal joint between the trapezium and metacarpal of the thumb.
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What is the term for movement of the trunk sideways to the right or left at the waist?
The movement of the trunk sideways to the right or left at the waist is called lateral flexion.
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What is hyperextension?
Hyperextension is a clinical condition associated with injury and describes a movement beyond the normal range of motion.
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Where may hyperextension occur?
Hyperextension may occur at joints such as the elbow, interphalangeal joints, and knee joint.
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In ____, there is an increase or decrease in the angle between articulating bones.
angular movements
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usually occur along the coronal plane.
Abduction and adduction
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What is abduction?
Abduction is the movement of a bone away from the midline.
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What is adduction?
Adduction is the movement of a bone toward the midline.
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What plane do abduction and adduction usually occur along?
Both movements usually occur along the coronal plane.
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What are examples of abduction?
Examples of abduction include moving the humerus laterally at the shoulder joint, moving the palm laterally at the wrist joint, and moving the femur laterally at the hip joint.
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What is the movement that returns body parts to the anatomical position after abduction?
The movement that returns each of these body parts to the anatomical position is adduction.
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What is radial deviation?
Radial deviation is the movement of the palm laterally at the wrist joint.
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What is ulnar deviation?
Ulnar deviation is the movement of the palm medially at the wrist joint.
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What is used as a point of reference for abduction and adduction of the digits?
The midline of the body is not used as a point of reference for abduction and adduction of the digits.
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What happens in abduction of the fingers?
In abduction of the fingers (but not the thumb), an imaginary line is drawn through the longitudinal axis of the middle (longest) finger, and the fingers move away (spread out) from the middle finger.
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How does abduction of the thumb occur?
In abduction of the thumb, the thumb moves away from the palm in the sagittal plane.
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What is the point of reference for abduction of the toes?
Abduction of the toes is relative to an imaginary line drawn through the second toe.
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What happens in adduction of the fingers and toes?
Adduction of the fingers and toes returns them to the anatomical position.
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How does adduction of the thumb occur?
Adduction of the thumb moves the thumb toward the palm in the sagittal plane.
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What is circumduction?
Circumduction is movement of the distal end of a body part in a circle.
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Is circumduction an isolated movement?
Circumduction is not an isolated movement by itself but rather a continuous sequence of flexion, abduction, extension, adduction, and rotation of the joint (or in the opposite order).
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Does circumduction occur along a separate axis or plane of movement?
Circumduction does not occur along a separate axis or plane of movement.
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What are examples of circumduction?
Examples of circumduction include moving the humerus in a circle at the shoulder joint, moving the hand in a circle at the wrist joint, moving the thumb in a circle at the carpometacarpal joint, moving the fingers in a circle at the metacarpophalangeal joints, and moving the femur in a circle at the hip joint.
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Which joints permit circumduction?
Both the shoulder and hip joints permit circumduction.
241
Why are flexion, abduction, extension, and adduction more limited in the hip joints than in the shoulder joints?
Flexion, abduction, extension, and adduction are more limited in the hip joints than in the shoulder joints due to the tension on certain ligaments and muscles and the depth of the acetabulum in the hip joint.
242
is the movement of the distal end of a body part in a circle
Circumduction
243
What is rotation?
Rotation is when a bone revolves around its own longitudinal axis.
244
What is an example of rotation?
One example of rotation is turning the head from side to side at the atlanto-axial joint (between the atlas and axis), as when you shake your head “no.”
245
What is another example of rotation?
Another example of rotation is turning the trunk from side to side at the intervertebral joints while keeping the hips and lower limbs in the anatomical position.
246
How is rotation defined in the limbs?
In the limbs, rotation is defined relative to the midline, and specific qualifying terms are used.
247
What is medial rotation?
If the anterior surface of a bone of the limb is turned toward the midline, the movement is called medial (internal) rotation.
248
How can the humerus be medially rotated at the shoulder joint?
You can medially rotate the humerus at the shoulder joint by starting in the anatomical position, flexing your elbow, and then moving your palm across the chest.
249
How can the femur be medially rotated at the hip joint?
You can medially rotate the femur at the hip joint by lying on your back, bending your knee, and then moving your leg and foot laterally from the midline.
250
How can medial rotation of the leg at the knee joint be produced?
Medial rotation of the leg at the knee joint can be produced by sitting on a chair, bending your knee, raising your lower limb off the floor, and turning your toes medially.
251
What is lateral (external) rotation?
If the anterior surface of the bone of a limb is turned away from the midline, the movement is called lateral (external) rotation.
252
a bone revolves around its own longitudinal axis.
rotation
253
occur only at certain synovial joints.
Special movements
254
What are special movements?
Special movements occur only at certain joints.
255
What are the examples of special movements?
The examples of special movements include elevation, depression, protraction, retraction, inversion, eversion, dorsiflexion, plantar flexion, supination, pronation, and opposition.
256
What is elevation?
Elevation is a superior movement of a part of the body, such as closing the mouth at the temporomandibular joint to elevate the mandible or shrugging the shoulders at the acromioclavicular joint to elevate the scapula and clavicle.
257
What is the opposing movement of elevation?
The opposing movement of elevation is depression.
258
What is depression?
Depression is an inferior movement of a part of the body, such as opening the mouth to depress the mandible or returning shrugged shoulders to the anatomical position to depress the scapula and clavicle.
259
What is protraction?
Protraction is a movement of a part of the body anteriorly in the transverse plane.
260
What is the opposing movement of protraction?
The opposing movement of protraction is retraction.
261
What is retraction?
Retraction is a movement of a protracted part of the body back to the anatomical position.
262
What is inversion?
Inversion is movement of the sole medially at the intertarsal joints.
263
What is the opposing movement of inversion?
The opposing movement of inversion is eversion.
264
What is eversion?
Eversion is a movement of the sole laterally at the intertarsal joints.
265
What is dorsiflexion?
Dorsiflexion refers to bending of the foot at the ankle or talocrural joint in the direction of the dorsum (superior surface).
266
What is the opposing movement of dorsiflexion?
The opposing movement of dorsiflexion is plantar flexion.
267
What is plantar flexion?
Plantar flexion involves bending of the foot at the ankle joint in the direction of the plantar or inferior surface.
268
What is supination?
Supination is a movement of the forearm at the proximal and distal radioulnar joints in which the radius and ulna are parallel to one another and the palm is turned anteriorly.
269
What is the opposing movement of supination?
The opposing movement of supination is pronation.
270
What is pronation?
Pronation is a movement of the forearm at the proximal and distal radioulnar joints in which the distal end of the radius crosses over the distal end of the ulna and the palm is turned posteriorly.
271
What is opposition?
Opposition is the movement of the thumb at the carpometacarpal joint in which the thumb moves across the palm to touch the tips of the fingers on the same hand.
272
Movement of relatively flat bone surfaces back- and- forth and side- to- side over one another; little change in angle between bones.
Gliding
273
Increase or decrease in angle between bones
Angular
274
Decrease in angle between articulating bones, usually in sagittal plane or an anterior movement at a ball- and- socket joint.
Flexion
275
Movement of trunk in frontal plane.
Lateral flexion
276
Increase in angle between articulating bones, usually in sagittal plane or a posterior movement at a ball- and- socket joint.
Extension
277
Movement of bone away from midline, usually in coronal plane.
Abduction
278
Movement of bone toward midline, usually in coronal plane.
Adduction
279
Flexion, abduction, extension, adduction, and rotation in succession (or in the opposite order); distal end of body part moves in circle.
Circumduction
280
Movement of bone around longitudinal axis; in limbs, may be medial (toward midline) or lateral (away from midline).
rotation
281
Occurs at specific joints.
Special
282
Superior movement of body part.
Elevation
283
Inferior movement of body part.
Depression
284
Anterior movement of body part in transverse plane.
Protraction
285
Posterior movement of body part in transverse plane.
Retraction
286
Medial movement of sole.
Inversion
287
Lateral movement of sole.
Eversion
288
Bending foot in direction of dorsum (superior surface).
Dorsiflexion
289
Bending foot in direction of plantar surface (sole).
Plantar flexion
290
Movement of forearm that turns palm anteriorly.
Supination
291
Movement of forearm that turns palm posteriorly.
Pronation
292
Movement of thumb across palm to touch fingertips on same hand.
Opposition
293
Synovial joints are divided into six categories based on type of movement:
plane, hinge, pivot, ellipsoid, saddle, and ball- and- socket.
294
What are the articulating surfaces of bones in a plane joint like?
The articulating surfaces of bones in a plane joint are flat or slightly curved.
295
What movements do plane joints primarily permit?
Plane joints primarily permit back-and-forth and side-to-side movements between the flat surfaces of bones, but they may also rotate against one another.
296
What type of movements can plane joints permit in terms of axes?
Many plane joints are biaxial, meaning that they permit movement in two axes.
297
What is an axis in terms of plane joints?
An axis is a straight line around which a bone rotates (revolves) or slides.
298
If plane joints rotate in addition to sliding, what type of movement do they permit?
If plane joints rotate in addition to sliding, then they are triaxial (multiaxial), permitting movement in three axes.
299
What are some examples of plane joints?
Some examples of plane joints are the intercarpal joints, intertarsal joints, acromioclavicular joints, sternocostal joints, and vertebrocostal joints.
300
Where are the intercarpal joints located?
The intercarpal joints are between carpal bones at the wrist.
301
Where are the intertarsal joints located?
The intertarsal joints are between tarsal bones at the ankle.
302
Where are the acromioclavicular joints located?
The acromioclavicular joints are between the acromion of the scapula and the clavicle.
303
Where are the sternocostal joints located?
The sternocostal joints are between the sternum and ends of the costal cartilages at the tips of the second through seventh pairs of ribs.
304
Where are the vertebrocostal joints located?
The vertebrocostal joints are between the heads and tubercles of ribs and bodies and transverse processes of thoracic vertebrae.
305
What is the shape of the convex surface of one bone in a hinge joint?
The convex surface of one bone fits into the concave surface of another bone.
306
What type of motion do hinge joints produce?
Hinge joints produce an angular, opening-and-closing motion like that of a hinged door.
307
In most joint movements, what remains in a fixed position while the other moves around an axis?
In most joint movements, one bone remains in a fixed position while the other moves around an axis.
308
How are hinge joints classified in terms of axes?
Hinge joints are uniaxial (monaxial) because they typically allow motion around a single axis.
309
What movements do hinge joints permit?
Hinge joints permit only flexion and extension.
310
What are examples of hinge joints?
Examples of hinge joints are the elbow, ankle, and interphalangeal joints.
311
What is another name for a pivot joint?
Another name for a pivot joint is a trochoid joint.
312
What kind of surface articulates in a pivot joint?
The rounded or pointed surface of one bone articulates with a ring formed partly by another bone and partly by a ligament.
313
How many axes does a pivot joint allow rotation around?
A pivot joint is uniaxial because it allows rotation only around its own longitudinal axis.
314
What is an example of a pivot joint?
An example of a pivot joint is the atlanto-axial joint.
315
What movement does the atlanto-axial joint permit?
The atlanto-axial joint permits the head to turn from side-to-side as when you shake your head “no.”
316
What is another example of a pivot joint?
Another example of a pivot joint is the radioulnar joints.
317
What movement do the radioulnar joints enable?
The radioulnar joints enable the palms to turn anteriorly and posteriorly as the head of the radius pivots around its long axis in the radial notch of the ulna.
318
What is another name for an ellipsoid joint?
Another name for an ellipsoid joint is a condylar joint.
319
What does the convex oval-shaped projection of one bone fit into in an ellipsoid joint?
The convex oval-shaped projection of one bone fits into the oval-shaped depression of another bone.
320
How many axes does an ellipsoid joint allow movement around?
An ellipsoid joint is biaxial because the movement it permits is around two axes (flexion–extension and abduction–adduction), plus limited circumduction.
321
What movements does an ellipsoid joint permit?
An ellipsoid joint permits flexion–extension, abduction–adduction, and limited circumduction.
322
What is an example of an ellipsoid joint?
An example of an ellipsoid joint is the radiocarpal joint (wrist).
323
What is another example of an ellipsoid joint?
Another example of an ellipsoid joint is the metacarpophalangeal joints (between the metacarpals and proximal phalanges) of the second through fifth digits.
324
What is another name for a saddle joint?
Another name for a saddle joint is a sellar joint.
325
What shape is the articular surface of one bone in a saddle joint?
The articular surface of one bone in a saddle joint is saddle-shaped.
326
How does the articular surface of the other bone fit into the saddle in a saddle joint?
The articular surface of the other bone fits into the “saddle” as a sitting rider would sit.
327
What are the movements at a saddle joint?
The movements at a saddle joint are the same as those at a condyloid joint: biaxial (flexion–extension and abduction–adduction) plus limited circumduction.
328
What is an example of a saddle joint?
An example of a saddle joint is the carpometacarpal joint between the trapezium of the carpus and the metacarpal of the thumb.
329
What is another example of a saddle joint?
Another example of a saddle joint is the sternoclavicular joint (between the manubrium of the sternum and the clavicle).
330
are classified into six principal types based on the shapes of the articulating bone surfaces
Synovial joints
331
What is another name for a ball-and-socket joint?
Another name for a ball-and-socket joint is a spheroidal joint.
332
What does a ball-and-socket joint consist of?
A ball-and-socket joint consists of the ball-like surface of one bone fitting into a cuplike depression of another bone.
333
How many axes do ball-and-socket joints have?
Ball-and-socket joints are triaxial (multiaxial).
334
What movements do ball-and-socket joints permit?
Ball-and-socket joints permit movements around three axes: flexion–extension, abduction–adduction, and rotation.
335
What is an example of a ball-and-socket joint?
An example of a ball-and-socket joint is the glenohumeral joint.
336
What is another example of a ball-and-socket joint?
Another example of a ball-and-socket joint is the hip joint.
337
Where does the head of the humerus fit in the glenohumeral joint?
In the glenohumeral (shoulder) joint, the head of the humerus fits into the glenoid cavity of the scapula.
338
Where does the head of the femur fit in the hip joint?
In the hip joint, the head of the femur fits into the acetabulum of the hip bone.
339
No articular Cavity; articulating Bones held together by Dense Irregular Connective tissue.
Fibrous
340
No articular Cavity; articulating Bones United by hyaline Cartilage or Fibrous Cartilage.
Cartilaginous
341
Characterized by Synovial Cavity, articular Cartilage, and articular (Joint) Capsule; May Contain accessory Ligaments, articular Discs, and Bursae.
Synovial
342
Articulating bones united by thin layer of dense irregular connective tissue, found between skull bones; with age, some sutures replaced by synostosis (separate cranial cavity bones fuse into single bone).
Suture
343
Degree of movement of suture
Immovable and slightly movable.
344
Example of suture
Coronal suture
345
Articulating bones united by a varying amount of dense irregular connective tissue, usually a ligament or membrane.
Syndesmosis
346
Degree of movement of syndesmosis
Slightly movable.
347
Example of syndesmosis
Distal tibiofibular joint and interosseous membrane between tibia and fibula (anterior tibiofibular ligament).
348
Connecting material: hyaline cartilage.
Synchondrosis
349
Degree of movement of Synchondrosis
Slightly movable to immovable.
350
Example of synchondrosis
Between first rib and manubrium of sternum. Epiphyseal cartilage between diaphysis and epiphysis of long bone
351
Connecting material: broad, flat disc of fibrous cartilage.
Symphysis
352
Degree of movement of Symphysis
Slightly movable to immovable.
353
Example of symphysis
Pubic symphysis and intervertebral joints.
354
Articulated surfaces flat or slightly curved.
Plane
355
Degree of movement of plane
Many are biaxial: back- and- forth and side- to- side movements. Some are triaxial: back- and- forth, side- to- side, rotation.
356
Example of plane
Intercarpal, intertarsal, sternocostal (between sternum and second to seventh pairs of ribs), and vertebrocostal joints.
357
Convex surface fits into concave surface.
Hinge
358
Degree of movement of hinge
Uniaxial: flexion– extension.
359
Example of hinge
Elbow, ankle, and interphalangeal joints.
360
Rounded or pointed surface fits into ring formed partly by bone and partly by ligament.
Pivot
361
Degree of movement of pivot
Uniaxial: rotation
362
Example of pivot
Atlanto- axial and radioulnar joints.
363
Oval- shaped projection fits into oval- shaped depression.
ellipsoid
364
Degree of movement of ellipsoid
Biaxial: flexion– extension, abduction– adduction
365
Example of ellipsoid
Radiocarpal and metacarpophalangeal joints.
366
Articular surface of one bone is saddle- shaped; articular surface of other bone “sits” in saddle.
Saddle
367
Degree of movement of saddle
Biaxial: flexion– extension, abduction– adduction.
368
Example of saddle
Carpometacarpal joint between trapezium and metacarpal of thumb.
369
Ball- like surface fits into cuplike depression.
Ball- and- socket
370
Degree of movement of Ball- and- socket
Triaxial: flexion– extension, abduction– adduction, rotation.
371
Example of Ball- and- socket
Glenohumeral and hip joints.
372
What do the articular surfaces of synovial joints do?
The articular surfaces of synovial joints contact one another and determine the type and possible range of motion.
373
What does range of motion (rOM) refer to?
Range of motion (rOM) refers to the amount of movement, measured in degrees of a circle, through which the bones of a joint can move.
374
What factors contribute to keeping the articular surfaces in contact and affect range of motion?
The following factors contribute to keeping the articular surfaces in contact and affect range of motion:
375
What is the first factor that contributes to keeping the articular surfaces in contact?
1. Structure or shape of the articulating bones.
376
How does the structure or shape of the articulating bones affect movement?
The structure or shape of the articulating bones determines how closely they can fit together.
377
What relationship is very obvious at the hip joint?
The articular surfaces of some bones have a complementary relationship. This spatial relationship is very obvious at the hip joint, where the head of the femur articulates with the acetabulum of the hip bone.
378
What does an interlocking fit allow in the hip joint?
An interlocking fit allows rotational movement.
379
What is the second factor that contributes to keeping the articular surfaces in contact?
2. Strength and tension (tautness) of the joint ligaments.
380
How do the different components of an articular capsule affect joint movement?
The different components of an articular capsule are tense or taut only when the joint is in certain positions. Tense ligaments not only restrict the range of motion but also direct the movement of the articulating bones with respect to each other.
381
How does the anterior cruciate ligament affect the knee joint when straightened?
In the knee joint, for example, the anterior cruciate ligament is taut and the posterior cruciate ligament is loose when the knee is straightened.
382
What happens to the ligaments when the knee is bent?
The reverse occurs when the knee is bent.
383
How do certain ligaments affect the hip joint when standing?
In the hip joint, certain ligaments become taut when standing and more firmly attach the head of the femur to the acetabulum of the hip bone.
384
What is the third factor that contributes to keeping the articular surfaces in contact?
3. Arrangement and tension of the muscles.
385
How does muscle tension affect joint movement?
Muscle tension reinforces the restraint placed on a joint by its ligaments, and thus restricts movement.
386
What is an example of the effect of muscle tension on a joint?
A good example of the effect of muscle tension on a joint is seen at the hip joint.
387
How is the flexion of the hip restricted when the knee is extended?
When the hip is flexed with the knee extended, the flexion of the hip is restricted by the tension of the hamstring muscles on the posterior surface of the thigh.
388
Why can most people not raise a straightened leg more than 90 degrees from the floor?
Most of us can’t raise a straightened leg more than a 90-degree angle from the floor.
389
How does flexing the knee affect the tension on the hamstring muscles?
But if the knee is also flexed, the tension on the hamstring muscles is lessened.
390
What happens when the tension on the hamstring muscles is lessened?
The thigh can be raised farther, allowing you to raise your thigh to touch your chest.
391
What is the fourth factor that contributes to keeping the articular surfaces in contact?
4. Contact of soft parts.
392
How does contact of soft parts limit mobility?
The point at which one body surface contacts another may limit mobility. For example, if you bend your arm at the elbow, it can move no farther after the anterior surface of the forearm meets with and presses against the biceps brachii muscle of the arm.
393
What other factor may restrict joint movement?
Joint movement may also be restricted by the presence of adipose tissue.
394
What is the fifth factor that contributes to keeping the articular surfaces in contact?
5. Hormones.
395
How do hormones affect joint flexibility?
Joint flexibility may also be affected by hormones.
396
What is an example of a hormone that increases flexibility during pregnancy?
For example, relaxin, a hormone produced by the placenta and ovaries, increases the flexibility of the fibrous cartilage of the pubic symphysis and loosens the ligaments between the sacrum, hip bone, and coccyx toward the end of pregnancy.
397
How do these hormonal changes affect the pelvic outlet?
These changes permit expansion of the pelvic outlet, which assists in delivery of the baby.
398
What is the sixth factor that contributes to keeping the articular surfaces in contact?
6. Disuse.
399
How does disuse affect movement at a joint?
Movement at a joint may be restricted if a joint has not been used for an extended period.
400
What is an example of restricted movement after a joint is immobilized?
For example, if an elbow joint is immobilized by a cast, range of motion at the joint may be limited for a time after the cast is removed.
401
How does disuse affect synovial fluid and ligaments?
Disuse may also result in decreased amounts of synovial fluid, diminished flexibility of ligaments and tendons, and muscular atrophy, a reduction in size or wasting of a muscle.
402
Between skull bones.
Skull
403
Classification of skull
Fibrous.
404
Movement of skull
none
405
Between superior articular facets of atlas and occipital condyles of occipital bone.
atlanto- occipital
406
Classification of atlanto- occipital
Synovial (ellipsoid).
407
Movement of atlanto-occipital
Flexion and extension of head; slight lateral flexion of head to either side.
408
(1) Between dens of axis and anterior arch of atlas; (2) between lateral masses of atlas and axis.
atlanto- axial
409
Classification of atlanto- axial
Synovial (pivot) between dens and anterior arch; synovial (planar) between lateral masses.
410
Movement of atlanto- axial
Rotation of head.
411
1) Between vertebral bodies; (2) between vertebral arches.
Intervertebral
412
Classification of Intervertebral
Cartilaginous (symphysis) between vertebral bodies; synovial (planar) between vertebral arches.
413
Movement of Intervertebral
Flexion, extension, lateral flexion, and rotation of vertebral column.
414
(1) Between articular facets of heads of ribs and costal facets of bodies of adjacent thoracic vertebrae and intervertebral discs between them; (2) between articular facet of tubercles of ribs and transverse costal facet of thoracic vertebrae.
Vertebrocostal
415
Classification of Vertebrocostal
Synovial(planar).
416
Movement of Vertebrocostal
Slight gliding
417
Between sternum and first seven pairs of ribs.
Sternocostal
418
Classification of Sternocostal
Cartilaginous(synchondrosis) between sternum and first pair of ribs; synovial (plane) between sternum and second through seventh pairs of ribs.
419
Movement of Sternocostal
None between sternum and first pair of ribs; slight gliding between sternum and second through seventh pairs of ribs.
420
(1) Between body of fifth lumbar vertebra and base of sacrum; (2) between inferior articular facets of fifth lumbar vertebra and superior articular facets of first vertebra of sacrum.
Lumbosacral
421
Classification of Lumbosacral
Cartilaginous (symphysis) between body and base; synovial (planar) between articular facets.
422
Movement of Lumbosacral
Flexion, extension, lateral flexion, and rotation of vertebral column
423
Between sternal end of clavicle, manubrium of sternum, and first costal cartilage.
Sternoclavicular
424
Classification of Sternoclavicular
Synovial (plane, pivot).
425
Movement of Sternoclavicular
Gliding, with limited movements in nearly every direction.
426
Between acromion of scapula and acromial end of clavicle.
acromioclavicular
427
Classification of acromioclavicular
Synovial (plane)
428
Movement of acromioclavicular
Gliding and rotation of scapula on clavicle.
