Chapter 8

Question 1

What are synarthrotic joints?

Answer 1

Synarthrotic joints are immovable joints.

Question 2

What connecting material is usually found in fibrous joints?

Answer 2

Fibrous joints are typically connected by collagen fibers.

Question 3

Which classification of joints are all classified as diarthrotic?

Answer 3

Synovial joints are all classified as diarthrotic, meaning freely movable.

Question 4

What is the difference between abduction and adduction?

Answer 4

Abduction is movement away from the midline of the body.
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Adduction is movement towards the midline of the body.

Question 5

What is the special term for extension of the ankle joint?

Answer 5

Extension of the ankle joint is called plantar flexion. This is when you point your toes.

Question 6

What are the two main types of cartilaginous joints?

Answer 6

Synchondrosis: joined by hyaline cartilage
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Symphysis: joined by fibrocartilage

Question 7

What is the source of synovial fluid?

Answer 7

The synovial membrane, which consists mostly of cells called synoviocytes, produces synovial fluid.

Question 8

How does synovial fluid provide nutrients and remove waste products from the articular cartilage?

Answer 8

Synovial fluid is forced in and out of the cartilage as the joint moves, acting as a pumping mechanism to replenish nutrients and remove waste products.

Question 9

What is a bursa (plural bursae)?

Answer 9

A bursa is a small, fluid-filled sac that acts as a cushion between structures that might rub against each other.

Question 10

Where is the acetabular labrum located and what is its function?

Answer 10

The acetabular labrum is a fibrocartilage ring that surrounds the acetabulum (socket) of the hip joint. It helps to deepen the socket and improve stability

Question 11

What is sciatica?

Answer 11

Sciatica is pain that radiates down the leg, caused by irritation of the sciatic nerve. This can occur due to a variety of factors, including a herniated disc or a tight piriformis muscle.

Question 12

What is hip dysplasia?

Answer 12

Hip dysplasia is an abnormal development of the hip joint where there is inadequate coverage of the femoral head by the acetabulum. This can lead to an increased risk of dislocation.

Question 13

What is the glenoid labrum?

Answer 13

he glenoid labrum is a ring of fibrocartilage that surrounds the glenoid fossa (socket) of the shoulder joint. It helps to deepen the socket and provide stability.

Question 14

In which direction does the shoulder most commonly dislocate?

Answer 14

The shoulder most commonly dislocates inferiorly (downward). This is because there is less muscular and ligamentous support on the inferior aspect of the joint.

Question 15

What is prepatellar bursitis?

Answer 15

Prepatellar bursitis is an inflammation of the bursa located between the skin and the patella (kneecap). It is commonly known as “housemaid’s knee” because it can be caused by repeated kneeling.

Question 16

What can happen if there is a tear in one of the collateral ligaments of the knee?

Answer 16

: A tear in a collateral ligament can lead to instability in the knee joint. The knee may displace either medially or laterally, depending on which ligament is torn.

Question 17

What are osteophytes and how can they affect joint movement?

Answer 17

Osteophytes, also known as bone spurs, are bony projections that can develop on the edges of bones. They can develop due to osteoarthritis and can interfere with normal joint movement.

Question 18

What is one potential cause of patellar dislocation?

Answer 18

One potential cause of patellar dislocation is a shallow patellar surface on the femur, which provides inadequate support for the kneecap.

Question 19

How can joints be categorized structurally?

Answer 19

Joints can be categorized structurally based on the type of material that holds the bones together:
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Fibrous: Dense connective tissue
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Cartilaginous: Hyaline cartilage or fibrocartilage
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Bony: Bone has replaced other material
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Synovial: Joint capsule

Question 20

How can joints be categorized functionally?

Answer 20

Joints can be categorized functionally based on their degree of mobility:
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Synarthrotic: Immovable
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Amphiarthrotic: Slightly movable
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Diarthrotic: Freely movable

Question 21

What is the trade-off between joint strength and flexibility?

Answer 21

There is an inverse relationship between joint strength and flexibility.
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Increased strength (resistance to dislocation) comes at the cost of decreased flexibility (ease and range of movement)
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Increased flexibility comes at the cost of decreased strength.

Question 22

What are the parts of a synovial joint?

Answer 22

Articular cartilage: Covers the bone surfaces
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Joint capsule: A fibrous connective tissue structure that encloses the joint cavity
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Synovial membrane: Lines the joint capsule and produces synovial fluid
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Synovial fluid: Lubricates the joint and nourishes the articular cartilage
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Ligaments: Connect bone to bone and reinforce the joint capsule
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Menisci (singular: meniscus): Fibrocartilage pads that provide cushioning and stability (knee joint)

Question 23

How do the parts of a synovial joint enhance movement?

Answer 23

Articular cartilage: Provides a smooth, low-friction surface for movement
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Synovial fluid: Lubricates the joint surfaces, allowing for smooth gliding

Question 24

How do the parts of a synovial joint enhance stability?

Answer 24

Joint capsule: Encloses the joint cavity and provides support
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Ligaments: Connect bone to bone, restrict excessive movement, and reinforce the joint capsule
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Menisci: Provide cushioning and stability, deepen the articulation, and help guide movement (knee joint)

Question 25

Why can diarthrotic (synovial) joints produce varying degrees of movement?

Answer 25

Diarthrotic joints can produce varying degrees of movement in one or more planes because of the shape of the articulating bone surfaces (joint surfaces).

Question 26

Pivot

Answer 26

Allows rotation around a single axis (Example: atlantoaxial joint - rotation of the head

Question 27

Hinge:

Answer 27

Allows flexion and extension in one plane (Example: elbow joint

Question 28

Condyloid (Ellipsoid):

Answer 28

Allows movement in two planes (biaxial) (Example: atlanto-occipital joint - nodding the head

Question 29

Saddle:

Answer 29

Allows movement in two planes and a slight rotational movement (biaxial) (Example: carpometacarpal joint of the thumb - opposition

Question 30

Plane (Gliding):

Answer 30

Allows gliding or sliding movements (Example: intercarpal joints

Question 31

Ball-and-Socket:

Answer 31

llows a wide range of motion in all three planes (multiaxial) (Example: hip joint

Question 32

How is the hip joint structurally organized?

Answer 32

Ball-and-socket joint between the head of the femur and the acetabulum of the pelvic bone ● Deep socket and strong ligaments contribute to stability ● Acetabular labrum (fibrocartilage ring) deepens the socket ● Reinforced by strong ligaments (iliofemoral, pubofemoral, ischiofemoral) that twist and tighten in a standing position

Question 33

How does the structure of the hip joint influence its flexibility?

Answer 33

The ball-and-socket structure allows for a wide range of motion, including flexion, extension, abduction, adduction, and rotation. ● However, the deep socket and strong ligaments limit flexibility compared to the shoulder joint

Question 34

What are the roles of ligaments and tendons in reinforcing the hip joint?

Answer 34

Ligaments (iliofemoral, pubofemoral, ischiofemoral) connect the femur to the pelvic bone, preventing excessive movement and reinforcing the joint capsule. ● Tendons of muscles surrounding the hip joint also contribute to stability by holding the joint in place.

Question 35

How is the shoulder joint structurally organized?

Answer 35

Ball-and-socket joint between the head of the humerus and the glenoid fossa of the scapula ● Shallow socket and less bony coverage compared to the hip joint ● Glenoid labrum (fibrocartilage ring) deepens the socket ● Reinforced by the rotator cuff muscles and their tendons

Question 36

How does the structure of the shoulder joint influence its flexibility?

Answer 36

The shallow socket and minimal bony restrictions allow for a wide range of motion, making it the most flexible joint in the body. ● However, this flexibility comes at the cost of stability, making the shoulder joint prone to dislocation.

Question 37

What are the roles of ligaments and tendons in reinforcing the shoulder joint?

Answer 37

Ligaments surround the joint capsule and provide some support. ● Tendons of the rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis) play a crucial role in stabilizing the shoulder joint, holding the humeral head in the glenoid fossa

Question 38

How is the knee joint structurally organized?

Answer 38

Modified hinge joint between the femur, tibia, and patella ● Condyles of the femur articulate with the relatively flat tibial plateaus ● Medial and lateral menisci (fibrocartilage pads) deepen the articulation and provide cushioning and stability ● Reinforced by multiple ligaments, including the cruciate ligaments (anterior and posterior) and collateral ligaments (medial and lateral) ● Patellar ligament connects the patella to the tibia

Question 39

How does the structure of the knee joint influence its flexibility?

Answer 39

Primarily allows flexion and extension (hinge-like motion) ● Some degree of rotation is possible when the knee is flexed ● Ligaments and menisci provide stability and guide movement, limiting flexibility compared to the hip or shoulder.

Question 40

What are the roles of ligaments and tendons in reinforcing the knee joint?

Answer 40

Ligaments: ○ Cruciate ligaments (anterior and posterior) prevent anterior-posterior displacement of the tibia relative to the femur. ○ Collateral ligaments (medial and lateral) prevent excessive side-to-side motion. ● Tendons: ○ Quadriceps tendon inserts on the patella and helps extend the knee. ○ Patellar ligament connects the patella to the tibia and also contributes to knee extension.

Question 41

What are some common types of injuries and disorders that can affect the hip joint?

Answer 41

Arthritis: Degeneration of articular cartilage, leading to pain and reduced mobility ● Hip dysplasia: Abnormal development of the hip joint, leading to increased risk of dislocation ● Sacroiliitis: Inflammation of the sacroiliac joint, causing lower back pain ● Sciatica: Pain radiating down the leg due to irritation of the sciatic nerve, potentially caused by a tight piriformis muscle

Question 42

What are some common types of injuries and disorders that can affect the shoulder joint?

Answer 42

Dislocation: Humeral head dislocates from the glenoid fossa, often inferiorly ● Rotator cuff tears: Tears in the tendons of the rotator cuff muscles, causing pain and weakness ● Impingement syndrome: Compression of tendons or bursa in the subacromial space, leading to pain and limited movement ● Bursitis: Inflammation of the bursae surrounding the shoulder joint, causing pain and swelling.

Question 43

What are some common types of injuries and disorders that can affect the knee joint?

Answer 43

Ligament tears: Tears in the ACL, PCL, MCL, or LCL, causing instability and pain ● Meniscus tears: Tears in the medial or lateral meniscus, leading to pain, clicking, and limited movement ● Bursitis: Inflammation of the bursae, especially the prepatellar bursa ("housemaid's knee") ● Arthritis: Degeneration of articular cartilage, leading to pain, stiffness, and reduced mobility ● Patellar dislocation: Displacement of the patella from its normal position