Podcast
Questions and Answers
Which of the following joints permits the greatest mobility?
Which of the following joints permits the greatest mobility?
The temporomandibular joint (TMJ) is a hinge joint only.
The temporomandibular joint (TMJ) is a hinge joint only.
False
What type of joint is the elbow?
What type of joint is the elbow?
Hinge joint
The hip joint is a ball-and-socket joint formed by the acetabulum of the coxal bone and the head of the _____
The hip joint is a ball-and-socket joint formed by the acetabulum of the coxal bone and the head of the _____
Signup and view all the answers
Match the following joint disorders with their descriptions:
Match the following joint disorders with their descriptions:
Signup and view all the answers
The scientific study of joints is known as ________.
The scientific study of joints is known as ________.
Signup and view all the answers
What type of connective tissue connects the bones in a fibrous joint?
What type of connective tissue connects the bones in a fibrous joint?
Signup and view all the answers
Sutures in the skull are classified as synarthroses in adulthood.
Sutures in the skull are classified as synarthroses in adulthood.
Signup and view all the answers
What is a gomphosis?
What is a gomphosis?
Signup and view all the answers
Which of the following is NOT a type of fibrous joint?
Which of the following is NOT a type of fibrous joint?
Signup and view all the answers
Cartilaginous joints allow for little or no ________.
Cartilaginous joints allow for little or no ________.
Signup and view all the answers
Match the following types of joints with their descriptions:
Match the following types of joints with their descriptions:
Signup and view all the answers
What type of tissue forms the articular capsule in synovial joints?
What type of tissue forms the articular capsule in synovial joints?
Signup and view all the answers
Synovial joints are the only joints that allow for freely moveable actions.
Synovial joints are the only joints that allow for freely moveable actions.
Signup and view all the answers
What fluid is secreted by the synovial membrane and serves to lubricate joints?
What fluid is secreted by the synovial membrane and serves to lubricate joints?
Signup and view all the answers
The movement of a body part away from the midline is known as abduction
The movement of a body part away from the midline is known as abduction
Signup and view all the answers
Match the type of synovial joint with its characteristic movement:
Match the type of synovial joint with its characteristic movement:
Signup and view all the answers
Which of the following is NOT a movement associated with synovial joints?
Which of the following is NOT a movement associated with synovial joints?
Signup and view all the answers
Bursitis refers to inflammation of the synovial membrane.
Bursitis refers to inflammation of the synovial membrane.
Signup and view all the answers
What is the function of bursae in joints?
What is the function of bursae in joints?
Signup and view all the answers
The articular capsule surrounds the synovial joint.
The articular capsule surrounds the synovial joint.
Signup and view all the answers
Which type of synovial joint allows for movement in multiple directions including flexion, extension, adduction, and abduction?
Which type of synovial joint allows for movement in multiple directions including flexion, extension, adduction, and abduction?
Signup and view all the answers
Study Notes
Joints (Articulations)
- Joints are sites of contact between bones.
- The study of joints is called arthrology.
Joint Classification
- Joints are classified based on structure.
- Two key questions to determine structural class:
- Is there an articular cavity between the bones?
- What type of connective tissue connects the bones?
Fibrous Joints
- Bones connected by dense irregular connective tissue.
- No articular cavity.
- Generally immobile.
- Three types:
-
Sutures:
- Connect cranial bones.
- Thin strip of dense irregular connective tissue.
- Become synostoses (fused bones) in adulthood.
-
Syndesmoses:
- Thicker and longer strip of dense irregular connective tissue called an interosseous ligament/membrane.
- Gomphosis is a specialized cone-shaped syndesmosis between teeth and mandible/maxilla.
-
Interosseous membranes:
- Sheets of dense irregular connective tissue.
- Hold 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:
- Connect bones with hyaline or fibrocartilage.
- Epiphyseal cartilages (hyaline) allow for bone growth.
-
Symphyses:
- Connected by fibrocartilage.
- Articular surfaces covered in hyaline cartilage.
-
Synchondroses:
Synovial Joints
- Distinguished by the presence of an articular cavity between bones.
- Bounded by an articular capsule.
- Bones covered in articular cartilage (hyaline).
- Freely moveable.
Articular Capsule
- Outer fibrous layer:
- Dense irregular connective tissue.
- Attaches to periosteum.
- Forms ligaments at some joints.
- Inner synovial membrane:
- Areolar connective tissue.
- Secretes synovial fluid.
- Synovial fluid functions:
- Nourishes chondrocytes of articular cartilage.
- Contains oxygen and nutrients.
- Contains immune cells.
- Reduces friction between bones.
- Absorbs shock.
Other Components of Synovial Joints
-
Accessory ligaments:
- Provide extra reinforcement for synovial joints.
- Examples: 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 evenly.
Bursae
- Reduce friction between moving structures.
- Similar structure to articular capsules: outer fibrous capsule and a synovial membrane.
- Found between bones and soft tissues (tendons, ligaments, etc.).
- Bursitis: Chronic inflammation of bursae.
Tendon Sheaths
- Tube-shaped bursae.
- Wrap around tendons experiencing a lot of friction.
- Example: The wrist.
Movements
- Synovial joints are the only freely moveable joints.
- Four main movement categories:
Gliding
- Nearly flat bones sliding back-and-forth and side-to-side.
- No angle change between articulating bones.
- Example: Intercarpal joints.
Angular Movements
- Increase or decrease angles between articulating bones.
- Includes:
- Flexion: Decreases angle between joined bones.
- Extension: Increases angle between joined bones.
- Lateral flexion: Decreases angle between bones in the coronal plane.
- Abduction: Movement of a bone away from the midline.
- Adduction: Movement of a bone towards 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 beyond 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: Bending the foot towards the shin.
- Plantar flexion: Bending the foot towards the sole.
- Inversion: Turning sole to face the midline.
- Eversion: Turning sole to face away from the midline.
- Supination/Pronation: Rotating the palm to face the sky/floor.
- Opposition: Movement of the pollex (thumb) at the carpometacarpal joints to touch other fingers (unique to primates).
Types of Synovial Joints
- Six types:
Plane Joints (Gliding Joints)
- Permit gliding movements.
- Biaxial movement.
- Examples:
- Intercarpal/intertarsal joints.
- Sternoclavicular joints.
- Vertebrocostal joints.
Hinge Joints
- Uniaxial movement: flexion/extension.
- Usually, one bone is fixed, and the other moves.
- Examples:
- Knee joints.
- Elbow joints.
- Ankle joints.
- Interphalangeal joints.
Pivot Joints
- Rounded surface of bone fitted into a ring made by a ligament and another bone.
- Uniaxial movement.
- Examples:
- Atlanto-axial joint (head shaking "no").
- Radioulnar joints (supination/pronation).
Condyloid Joints (Ellipsoidal Joints)
- Oval-shaped protrusion fits into an oval-shaped depression.
- Biaxial movement: flexion/extension, abduction/adduction, or circumduction.
- Example: Radiocarpal joints (wrist).
Saddle Joints
- One bone shaped like a saddle, and the other like a rider.
- Biaxial movement: flexion/extension, abduction/adduction, or circumduction.
- Example: Carpometacarpal joint between the proximal metacarpal of the thumb and trapezium.
Ball-and-Socket Joints
- Ball-shaped projection fits into a cup-shaped depression.
- Triaxial movement: flexion/extension, abduction/adduction, circumduction, and rotation.
- Examples: Shoulder and hip joints.
Special Examples of Joints
Temporomandibular Joint (TMJ)
- Only freely moveable joint in the skull.
- Combination of hinge and plane joint.
- Articulation between the condylar process of the mandible and mandibular fossa of the temporal bone.
- Articular components:
- Articular capsule.
- Multiple ligaments stabilize the joint.
- Meniscus subdivides the synovial cavity into superior and inferior compartments.
- Superior: Permits slight rotation, lateral displacement, protraction/retraction.
- Inferior: Permits depression/elevation.
- Movements:
- Depression/elevation.
- Protraction/retraction.
- Lateral displacement (side to side).
- Some rotation.
Glenohumeral Joint (Shoulder)
- Ball-and-socket.
- Thin, loose articular capsule: important for great ROM.
- Articular components:
- Many ligaments reinforcing the joint.
-
Glenoid labrum: Fibrocartilage lip of the glenoid cavity.
- Increases surface area of glenoid cavity contacting the humeral head.
- Bursae: Four pads absorbing shock and reducing friction between articular components.
- Movements:
- Flexion, extension, hyperextension.
- Abduction, adduction.
- Medial and lateral rotation.
- Circumduction.
- Great ROM but less stable than the coxal joint.
Elbow Joint
- Formed by humerus, ulna, and radius.
- Articular components:
- Articular capsule.
- Collateral ligaments: Accessory ligaments connecting humerus to radius or ulna.
- Annular ligament: Ring-like ligament holding the radial head to the radial notch of the ulna.
- Bursa at the olecranon.
- Movement: Flexion or extension (hinge joint).
Coxal (Hip) joint
- Ball-and-socket joint formed by the acetabulum of the coxal bone and the head of the femur.
- Very stable due to:
- Number and arrangement of ligaments.
- Specific fit of the femoral head in the acetabulum.
- Articular components:
- Thick articular capsule.
- Acetabular labrum: Fibrocartilage lip of the acetabulum preventing femoral head displacement.
- Accessory ligaments: Numerous and strong, reinforcing the articular capsule but limiting ROM compared to the shoulder joint.
- Movements:
- Flexion/extension.
- Abduction/adduction.
- Lateral and medial rotation.
- Circumduction.
Knee Joint
- Modified hinge joint.
- Three joints sharing one synovial cavity:
- Lateral joint (femur and tibia).
- Medial joint (femur and tibia).
- Anterior patellofemoral joint (plane joint).
- Articular components:
- No single identifiable articular capsule.
- Collection of muscle tendons serves a similar function.
- Cruciate ligaments: Accessory ligaments crossing one another.
- Collateral ligaments: Reinforce connection between femur/tibia, femur/fibula.
- Menisci: One medial, one lateral.
- Bursae: Several, including the infrapatellar bursa between the tibia and patellar ligament.
- No single identifiable articular capsule.
- Movements:
- Flexion/extension.
Joint Diseases and Disorders
-
Arthritis:
- Osteoarthritis: Progressive loss of articular cartilage, resulting in increased friction between articulating bones.
- Rheumatoid arthritis: Autoimmune disorder causing inflammation of the synovial membrane, leading to cartilage destruction and bone erosion.
-
Sprains and Strains:
- Sprains: Forceful stretching or tearing of ligaments (no bone dislocation).
- Strains: Partially torn or stretched muscle or tendon.
- Treatment for sprains and strains: PRICE (Protection, Rest, Ice, Compression, Elevation).
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge about joints and their classifications in this quiz on arthrology. Explore different types of joints, particularly fibrous joints, and their structural characteristics. Understand the key concepts of joint types and their functions.
