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What is the scientific study of joints called?
Fibrous joints typically have an articular cavity.
False
Name the type of joint that connects the cranial bones.
sutures
The primary type of cartilage found in synchondroses is _________.
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Which of the following joints is classified as a gomphosis?
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Match the types of joints with their characteristics:
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What type of joint has no articular cavity and allows for little or no movement?
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Interosseous membranes are ________ made of dense irregular connective tissue that holds diaphyses of adjacent long bones together.
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What type of cartilage is involved in symphyses joints?
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Synovial joints are considered freely movable joints.
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What is the primary function of synovial fluid?
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The ___________ membrane secretes synovial fluid in synovial joints.
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Match the joint type to its description:
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Which of the following movements describes moving a body part toward the midline?
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Bursae are structures that provide cushioning and reduce friction in joints.
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Name one example of a pivot joint.
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Which type of joint permits the greatest mobility?
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The temporomandibular joint (TMJ) is a type of saddle joint.
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Increased flexibility around the ____________ capsule can sometimes lead to dislocations in double-jointed individuals.
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What is a characteristic of saddle joints?
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What is the primary movement permitted by the elbow joint?
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The glenohumeral joint has a _____ articular capsule that is important for a great range of motion.
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Flexion decreases the angle between joined bones.
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Match the following joints with their classifications:
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What type of connective tissue primarily composes the fibrous layer of the articular capsule?
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Inversion involves turning the foot's sole __________ from the midline.
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What is the main function of the menisci in the knee joint?
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Which joint type allows for the most movement?
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The hip joint is less stable than the shoulder joint.
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What type of joint is the knee classified as?
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Osteoarthritis is characterized by the progressive loss of _______.
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Which ligament holds the radial head to the radial notch of the ulna?
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The coxal joint is composed of only two bones.
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List the movements permitted by the shoulder joint.
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Sprains involve the stretching or tearing of _______.
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Match the following joints with their descriptions:
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Study Notes
Introduction to Joints
- Joints are also known as articulations or arthroses.
- Joints are sites of contact between bones.
- Arthrology is the scientific study of joints.
Classification of Joints
- Joints are classified by their structure.
- Two questions determine structural classes:
- Is there an articular cavity between the articulating bones?
- What type of connective tissue connects the bones of the joint?
Fibrous Joints
- Joined by dense irregular connective tissue.
- No articular cavity.
- Generally immobile.
- Three types:
- Sutures:
- Connect cranial bones with a thin strip of dense irregular connective tissue.
- By adulthood, sutures become synarthroses.
- Syndesmoses:
- Thicker and longer strip of dense irregular connective tissue (interosseous ligament/membrane).
- A gomphosis is a cone-shaped joint between teeth and the mandible or maxilla.
- Interosseous membranes:
- Made of dense irregular connective tissue.
- Holds diaphyses of adjacent long bones together (e.g., distal limbs).
- Sutures:
Cartilaginous Joints
- Bones joined by cartilage.
- No articular cavity.
- Little or no movement.
- Two subtypes:
- Synchondroses:
- Connects bones with hyaline or fibrocartilage cartilage.
- Epiphyseal cartilages are hyaline cartilage that permits bone growth.
- Symphyses:
- Held by fibrocartilage.
- Bones are still covered in hyaline cartilage at articular surfaces.
- Synchondroses:
Synovial Joints
- Distinguished by the presence of an articular cavity between bones.
- Bounded by an articular capsule.
- Secretes lubricating fluid.
- Bones are covered in articular cartilages (hyaline cartilage).
- Freely moveable.
- Articular capsule:
- Bounds the articular cavity.
- Two layers:
- Fibrous layer (outer): dense irregular connective tissue, attaches to periosteum, forms ligaments at some joints.
- Synovial membrane (inner): areolar connective tissue, secretes synovial fluid.
- Synovial fluid:
- Viscous, clear or pale yellow.
- Functions: nourishes chondrocytes of articular cartilage, contains oxygen and nutrients, contains immune cells, reduces friction between bones at joints, absorbs shock.
- "Double-jointed" people:
- Have increased flexibility around the articular capsule and ligaments of joints.
- Increased risk for dislocation (disruption of articulations).
- Components:
- Accessory ligaments: provide extra reinforcement for synovial joints (e.g., collateral and cruciate ligaments of the knee).
- Articular discs or menisci: fibrocartilage padding attached to the inside surface of the fibrous capsule, absorb shock and distribute weight more evenly.
Bursae
- Reduce friction between moving structures.
- Similar structure to articular capsules (outer fibrous capsule and a synovial membrane).
- Found between bones and soft tissue (tendons, ligaments, etc.).
- Bursitis: chronic inflammation of bursae.
Tendon Sheaths
- Tube-shaped bursae.
- Wrap around tendons that experience a lot of friction (e.g., the wrist).
Movements
- Synovial joints are the only freely moveable joints.
- Four main categories of movement:
- Gliding: nearly flat bones slide back-and-forth and side-to-side, no change in angle between articulating bones (e.g., intercarpal joints).
- Angular movements: increase or decrease angles between articulating bones:
- Flexion: decrease in angle between joined bones.
- Extension: increase in angle between joined bones.
- Lateral flexion: decrease in angle between bones in the coronal plane.
- Abduction: movement of a bone away from a midline.
- Adduction: movement toward the midline.
- Circumduction: movement around a joint to move the distal part of a limb in a circle (combines flexion, extension, abduction, and adduction).
- Hyperextension: extension over the physiological limit.
- Rotation: turning of a bone along its longitudinal axis (may be medial or lateral in the limbs).
- Special movements: movements unique to specific joints.
- Mandible: elevation, depression, protraction, retraction.
- Hands and feet: dorsiflexion, plantar flexion, inversion, eversion, supination, pronation, opposition.
Types of Synovial Joints
- Six types:
- Plane joints: permit gliding, movements are biaxial (e.g., intercarpal or -tarsal joints, sternoclavicular joints, vertebrocostal joints).
- Hinge joints: movement is uniaxial (flexion/extension), usually one bone is fixed and the other moves (e.g., knee joints, elbow joints, ankle joints, interphalangeal joints).
- Pivot joints: rounded surface of bone fitted to a ring made by a ligament + other bone, permits uniaxial movement (e.g., the atlanto-axial joint, radioulnar joints).
- Condyloid joints (ellipsoidal joints): oval-shaped protrusion fits an oval-shaped depression, permits biaxial movement (flexion/extension, abduction/adduction, or circumduction) (e.g., radiocarpal joints).
- Saddle joints: one bone looks like a saddle and the other bone looks like a rider, permits biaxial movement (flexion/extension, abduction/adduction, or circumduction) (e.g., carpometacarpal joint between proximal metacarpal of the thumb and trapezium).
- Ball-and-socket joints: ball-shaped projection fits into a cup-shaped depression, permits triaxial movement (flexion/extension, abduction/adduction, circumduction, rotation) (e.g., the shoulder and hip joints).
Special Examples of Joints
- Temporomandibular joint (TMJ):
- Only freely moveable joint in the skull.
- Combination hinge and plane joints.
- Articulation between the condylar process of the mandible and mandibular fossa of the temporal bone.
- Articular components: articular capsule, multiple ligaments, meniscus subdivides synovial cavity into superior (permits slight rotation, lateral displacement, protraction/retraction) and inferior (permits depression/elevation).
- Movements: depression/elevation, protraction and retraction, lateral displacement, some rotation.
- Glenohumeral joint (shoulder):
- Ball-and-socket joint.
- Thin, loose articular capsule (important for great range of motion).
- Articular components: many ligaments, glenoid labrum (fibrocartilage lip or rim of the glenoid cavity), bursae.
- Movements: flexion, extension, hyperextension, abduction, adduction, medial and lateral rotation, circumduction.
- Elbow joint:
- Formed by humerus, ulna, and radius.
- Articular components: articular capsule, collateral ligaments, annular ligament, bursa at the olecranon.
- Movement: flexion or extension.
- Coxal or hip joint:
- Ball-and-socket joint formed by the acetabulum of the coxal bone + head of the femur.
- Very stable joint due to number and arrangement of ligaments and specific fit of the femoral head in the acetabulum.
- Articular components: thick articular capsule, acetabular labrum, accessory ligaments.
- Movements: flexion/extension, abduction/adduction, lateral and medial rotation, circumduction.
- Knee joint:
- Modified hinge joint (three joints that share one synovial cavity).
- Articular components: no single identifiable articular capsule, cruciate ligaments, collateral ligaments, menisci, bursae.
- Movements: flexion, extension, slight medial and lateral rotation.
- Ankle joint:
- Hinge joint, allows dorsiflexion and plantar flexion.
- Two bones are involved: tibia and fibula.
Joint Diseases and Disorders
- Arthritis:
- Osteoarthritis: progressive loss of articular cartilage, results in increased friction between articulating bones, may require surgery.
- Sprains and strains:
- Sprains: forceful stretching or tearing of ligaments, no bone dislocation, may require surgery.
- Strains: partially torn or stretched muscle or tendon, treatment = PRICE (protection, rest, ice, compression, elevation).
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Description
This quiz explores the structure and classification of joints, also known as articulations or arthroses. Learn about the types of fibrous joints, their characteristics, and the scientific study of joints known as arthrology.
