Chapter 8 Articulations
Module 8.1 Overview of Joints
Learning Outcomes
- Describe the basic functions of joints.
- Describe how joints are classified both structurally and functionally.
Module 8.2 Fibrous and Cartilaginous Joints
Learning Outcomes
- Compare and contrast the three subclasses of fibrous joints.
- Give examples of fibrous joints and describe how they function.
- Compare and contrast the two subclasses of cartilaginous joints.
- Give examples of cartilaginous joints, and describe their function.
Module 8.3 Structure of Synovial Joints
Learning Outcomes
- Identify the structural components of a synovial joint.
- Compare and contrast synovial joints with fibrous and cartilaginous joints.
Module 8.4 Function of Synovial Joints
Learning Outcomes
- Define the functional classes of synovial joints.
- Describe and demonstrate the movements of synovial joints
Module 8.5 Types of Synovial Joints
Learning Outcomes
- Describe the anatomical features of each structural type of synovial joint.
- Describe where each structural type can be found.
- Predict the kinds of movements that each structural type of synovial joint will allow.
- Compare and contrast the structural features of the knee and elbow and of the shoulder and hip.
Notes part A
Notes part B
Knowledge sheets
Answers
Workbook
Answers
Key Topics for the above video.
Synovial joint structure
Joint cavity function
Ligament classifications
Synovial joint types
Bursitis causes
Synovial Joints: Structure, Function, and Pathology
Synovial Joints Study Guide
Quiz
Instructions: Answer each question in 2-3 complete sentences.
1.
What is the key structural characteristic that distinguishes synovial joints from fibrous and cartilaginous joints?
2.
How does articular cartilage contribute to the function of a synovial joint?
3.
Describe the function of synovial fluid within a joint cavity.
4.
What are the three classifications of ligaments based on their relationship to the articular capsule, and where are they located?
5.
How do tendons and muscles provide additional support to synovial joints, and why is this important?
6.
What is the difference between an articular disc and a meniscus, and what functions do they serve?
7.
What is the function of bursae and tendon sheaths?
8.
Describe the symptoms and causes of bursitis.
9.
What are the six types of synovial joints?
10.
Give an example of a joint for each of the six synovial joint types.
Quiz Answer Key
1.
The key structural characteristic of synovial joints is the presence of a joint cavity, a fluid-filled space where the articulating surfaces of bones make contact. This space is absent in both fibrous and cartilaginous joints, where bones are connected directly.
2.
Articular cartilage is a thin layer of hyaline cartilage covering the articulating surface of each bone within a synovial joint. It acts like a Teflon® coating, allowing bones to move smoothly against each other without damaging the underlying bone tissue, minimizing friction and wear.
3.
Synovial fluid is a thick, slimy fluid secreted by the synovial membrane lining the articular capsule. It provides lubrication to reduce friction between the bones of the joint and also provides nourishment to the articular cartilage, which lacks blood vessels.
4.
Extrinsic ligaments are located outside of the articular capsule, intrinsic ligaments are fused to or incorporated into the wall of the articular capsule, and intracapsular ligaments are located inside of the articular capsule. These ligaments support the joint by anchoring the bones together and preventing separation.
5.
Tendons attach muscles to bones and increase muscle contraction when forces increase at a joint. By doing so, muscles and tendons serve as a "dynamic ligament" to resist forces and support the joint. This is particularly important where ligaments may be weak.
6.
Articular discs are generally small and oval-shaped structures located between articulating bones, while menisci are larger and C-shaped structures. They both may act to unite bones, provide cushioning and shock absorption, and smooth movements between articulating bones within the joint.
7.
Bursae are thin, connective tissue sacs filled with lubricating fluid that reduce friction between skin, ligaments, muscles, or muscle tendons and an underlying bone. Tendon sheaths are similar in structure to bursae, but smaller, and surround muscle tendons where they cross a joint, also providing lubrication.
8.
Bursitis, the inflammation of a bursa, causes pain, swelling, or tenderness in the affected area, often resulting in joint stiffness. It can result from muscle overuse, trauma, prolonged pressure on the skin, rheumatoid arthritis, gout, or infection of the joint.
9.
The six types of synovial joints are: pivot joints, hinge joints, condyloid joints, saddle joints, plane joints, and ball-and-socket joints.
10.
Examples of the six types of synovial joints are: atlantoaxial joint (pivot), elbow joint (hinge), knuckle (metacarpophalangeal) joints (condyloid), first carpometacarpal joint of the thumb (saddle), intercarpal joints (plane), and the hip joint (ball-and-socket).
Essay Questions
Instructions: Answer the following questions in essay format.
1.
Compare and contrast the structure and function of cartilaginous joints and synovial joints, highlighting the key features that distinguish the two.
2.
Discuss the importance of the various structures associated with synovial joints (e.g., articular cartilage, synovial fluid, ligaments, tendons, bursae) in maintaining joint health and function.
3.
Explain how the classification of synovial joints based on their shape directly relates to the range of movement allowed at each joint, providing examples to support your answer.
4.
Describe the causes, symptoms, and treatments for bursitis. Also, discuss the different types of bursae and their locations within the body.
5.
Explain the difference between a "dynamic ligament" and a ligament. Discuss the importance of the dynamic ligament in the human body.
Glossary
Articular Capsule: The fibrous connective tissue structure that surrounds a synovial joint, enclosing the joint cavity.
Articular Cartilage: A thin layer of hyaline cartilage that covers the articulating surfaces of bones in a synovial joint, reducing friction and allowing smooth movement.
Articular Disc: A small, oval-shaped fibrocartilage structure found between some articulating bones of a synovial joint, serving to unite bones, provide cushioning, and smooth movement.
Ball-and-Socket Joint: A synovial joint in which a rounded head of one bone fits into the concave articulation of an adjacent bone, allowing the greatest range of motion (multiaxial).
Bursae: Thin, connective tissue sacs filled with lubricating fluid, located in areas where skin, ligaments, muscles, or muscle tendons can rub against each other, reducing friction.
Bursitis: Inflammation of a bursa near a joint, causing pain, swelling, and stiffness.
Condyloid Joint: Also known as an ellipsoid joint, a synovial joint in which a shallow depression at the end of one bone articulates with a rounded structure of an adjacent bone, allowing for biaxial movement.
Diarthrosis: A freely movable joint, characteristic of all synovial joints.
Extrinsic Ligament: A ligament located outside the articular capsule of a synovial joint.
Hinge Joint: A synovial joint in which the convex end of one bone articulates with the concave end of an adjacent bone, allowing only for bending and straightening motions (uniaxial).
Intrinsic Ligament: A ligament that is fused to or incorporated into the wall of the articular capsule of a synovial joint.
Intracapsular Ligament: A ligament located inside of the articular capsule of a synovial joint.
Joint Cavity: The fluid-filled space between the articulating bones of a synovial joint.
Ligament: A strong band of fibrous connective tissue that connects bones to each other, providing support and limiting excessive joint movement.
Meniscus: A larger, C-shaped fibrocartilage structure that serves to provide cushioning and shock absorption between the bones of a synovial joint, such as in the knee.
Plane Joint: A synovial joint in which the articulating surfaces of bones are flat or slightly curved, allowing for limited gliding movements (multiaxial).
Pivot Joint: A synovial joint in which a rounded portion of a bone is enclosed within a ring formed partially by another bone and partially by a ligament, allowing for rotation around a single axis (uniaxial).
Saddle Joint: A synovial joint in which both of the articulating surfaces have a saddle shape (concave in one direction and convex in the other), allowing for biaxial movement.
Subcutaneous Bursa: A bursa located between the skin and an underlying bone.
Submuscular Bursa: A bursa located between a muscle and an underlying bone or between adjacent muscles.
Subtendinous Bursa: A bursa located between a tendon and a bone.
Synovial Fluid: A thick, slimy fluid secreted by the synovial membrane that provides lubrication and nourishment to the articular cartilage.
Synovial Joint: A joint that has a joint cavity, articular cartilage, and synovial fluid, allowing for smooth movement between articulating bones.
Synovial Membrane: The thin membrane lining the inner surface of the articular capsule in a synovial joint.
Tendon: The dense connective tissue structure that attaches a muscle to bone.
Tendon Sheath: A connective tissue sac that surrounds a muscle tendon at places where the tendon crosses a joint, containing a lubricating fluid that allows for smooth motions.