Lecture 14,15,16

What primarily determines the amount of movement allowed at a joint?

The anatomical structure of the joint.

How are joints functionally categorized?

By the amount of motion allowed, or range of motion (ROM).

Which functional classification of joints allows no movement?

Synarthrosis.

What type of joints allow little movement and have articulating bones connected by collagen fibers or cartilage?

Amphiarthrosis.

Which functional classification describes freely movable joints?

Diarthrosis.

How are joints structurally categorized?

By their anatomical organization, specifically the type of connective tissue holding them together.

What kind of tissue is present between bones in fibrous joints?

Dense connective tissue.

Which is a non-moving (synarthrosis) cartilaginous joint?

Synchondrosis.

Where are most synarthroses and symphyses found?

The axial skeleton.

How are synovial joints functionally classified?

Diarthrotic.

What is a key characteristic of synovial joints regarding their range of motion?

They permit a wider range of motion than any other joint type.

What covers the surfaces of bones at a synovial joint?

Articular cartilage.

What does articular cartilage lack?

Perichondrium.

What surrounds the entire synovial joint?

Joint capsule (or articular capsule).

What is the primary function of the synovial membrane?

To secrete synovial fluid into the joint cavity.

What is the approximate total volume of synovial fluid typically found in a joint cavity?

Usually less than 3 mL.

What is a key function of synovial fluid?

To provide oxygen and nutrients to chondrocytes.

The consistency of synovial fluid is comparable to what?

Raw egg white.

How does synovial fluid contribute to shock absorption?

By increasing its viscosity with increasing pressure.

Which accessory structure of the knee joint limits range of motion and provides mechanical support?

Tendon of the quadriceps muscle.

What is a small, fluid-filled pocket to reduce friction called?

Bursa.

What is the medical term for an inflamed bursa?

Bursitis.

Describe fat pads in a joint.

Localized masses of adipose tissue covered by a layer of synovial membrane, protecting articular cartilage.

What is a pad of fibrocartilage found between opposing bones in a synovial joint called?

Meniscus (or articular disc).

What is the general relationship between a joint's mobility and its stability?

More mobile joints are generally less stable.

Which type of joint is considered the strongest and allows no movement?

Synarthroses.

Which type of joint is the most mobile but also the weakest?

Diarthroses.

What term describes movement beyond the normal range of motion where articulating surfaces are forced out of position?

Dislocation (or luxation).

Where does pain during a joint dislocation primarily originate?

Nerves monitoring the joint capsule and surrounding tissue.

Which statement is true regarding pain receptors within a joint?

There are no pain receptors inside a joint.

What type of synovial movement permits sliding in any direction on a relatively flat surface?

Gliding

What does angular motion at synovial joints involve in addition to movement along two axes?

A change in angle

What is the term for a complex angular movement where the proximal end of a bone is fixed?

Circumduction

Which angular movement describes a decrease in the angle of a hinge joint?

Flexion

Increasing the angle of a joint is known as what angular movement?

Extension

What is the term for extension occurring past the anatomical position?

Hyperextension

Bending the vertebral column to the side is known as what?

Lateral flexion

What foot movement involves an upward movement of the foot or toes?

Dorsiflexion

What movement extends the ankle, such as standing on tiptoe?

Plantar flexion

What term defines movement of the appendicular skeleton away from the longitudinal axis?

Abduction

What movement involves moving a body part toward the longitudinal axis?

Adduction

Movement around the longitudinal axis, where the bone shaft rotates, is called what?

Rotation

What type of rotation turns the anterior surface of a limb toward the long axis of the trunk?

Medial rotation

What term describes the rotation of the forearm that turns the palm facing back?

Pronation

Turning the palm anteriorly is called what?

Supination

What is the movement of the thumb toward the surface of the palm called?

Opposition

What twisting motion turns the sole of the foot inward?

Inversion

Moving a part of the body anteriorly in the horizontal plane is known as what?

Protraction

Movement that refers to lowering a body part is called what?

Depression

What best characterizes axial joints?

Strong joints permitting very little movement

Which axial joint permits a nodding action?

Atlanto-occipital joint

What is a key characteristic of appendicular joints?

Extensive range of motion

What type of joint is found in the vertebral column, forming intervertebral discs?

Symphyses

What is the core of an intervertebral disc that provides shock absorption?

Nucleus pulposus

What component of a herniated disc breaks through the anulus fibrosus?

Nucleus pulposus

What is a notable feature of the shoulder joint (glenohumeral joint)?

It has the greatest range of motion and is frequently dislocated.

How does the hip joint compare to the shoulder joint in stability?

It is a sturdy ball-and-socket joint reinforced by ligaments.

What contributes to the stability of the elbow joint?

The interlocking bony surfaces of the humerus and ulna.

How many separate articulations are in the knee joint?

Three

What example is given for a second-class lever in the human body?

Contraction of the calf muscles to elevate the body.

What condition is characterized by inadequate ossification leading to loss of bone mass, often occurring with age and being more severe in women?

Osteoporosis

What is bone loss sufficient to affect normal function known as?

Osteoporosis

What leads to vertebral fractures in the elderly due to loss of bone mass?

Reduced cushioning of intervertebral discs

What clinical example is associated with the movement of the metatarsal/phalanx joint out of alignment?

Bunions

What is the general term indicating pain and stiffness in the bones and/or muscles?

Rheumatism

What are all rheumatic diseases that affect synovial joints and result in damage to articular cartilage collectively termed?

Arthritis

Which joints does arthritis specifically disrupt normal structure and function by affecting?

Synovial joints

What is the fundamental type of damage always involved in rheumatic diseases that affect synovial joints?

Damage to the articular cartilage

How many primary types of arthritis are discussed in the sources?

Three

Which type of arthritis is described as an inflammatory autoimmune arthritis?

Rheumatoid arthritis

What joints are most commonly affected by rheumatoid arthritis?

Wrist and fingers

Rheumatoid arthritis is stated to be more common in which demographic?

Women

Which condition is characterized by an immune attack of the synovial membranes?

Rheumatoid arthritis

What is the typical age range for the onset of rheumatoid arthritis?

Ages 25-55

Which arthritis form is often first noted to attack the large toe?

Gouty arthritis

Gouty arthritis is frequently associated with what factors?

Alcohol consumption and certain foods

What substance builds up as the cause of gouty arthritis?

Uric acid crystals

Which type of arthritis is known as "wear and tear" arthritis?

Osteoarthritis

What is the most common form of arthritis?

Osteoarthritis

Osteoarthritis most commonly affects which areas of the body?

Hands, knees, hips, spine

What primarily causes osteoarthritis?

Cumulative effects of wear and tear on joints and genetic factors

What percentage of women over age 60 in the United States are affected by osteoarthritis?

25 percent

What are the characteristics of normal articular cartilage?

Smooth, slick surface and thick cartilage with homogeneous matrix

When articular cartilage is damaged by osteoarthritis, how does its surface change?

Rough and bristly

What is a narrow, flexible fiberoptic tube with a tiny camera used to explore a joint without major surgery called?

Arthroscope

Which diagnostic tool is noninvasive and cost-effective for visualizing soft tissue outside the joint cavity?

Magnetic resonance imaging (MRI)

Artificial joints may be considered as a method of last resort if what other methods fail?

Regular exercise, physical therapy, and anti-inflammatory drugs

What are the primary benefits of artificial joint replacement?

Restoration of mobility and relief of pain

After artificial joint replacement, what activity is typically restricted for patients?

High-impact activities

New artificial joints for hips and knees can last for more than how many years?

15 years