Joints - Introduction Flashcards
What are the Two Types of Classifications for Joints?
- Functional
- Anatomical
What are the Three Types of Functional Classification for Joints? Describe Them
- Synarthrosis: Very little to no movement
- Amphiarthrosis: Semi-movable
- Diarthrosis: Freely movable
What are the Two Types of Anatomical Classification for Joints? What basic characteristics to they have?
- Solid Joints: Held together by connective tissue. Fibrous/Cartilaginous
- Synovial Joints: Presence of cavity between bones. Held together by fibrous capsule, all are diarthrosis type.
What are the Two Classifications for Solid Joints? What is the difference?
- Fibrous Joints: Bones are held together by dense connective tissue.
- Cartilaginous Joints: Bones are held together by cartilage with limited movement.
What are the Three Types of Fibrous Joints? Describe them and give an example
- Sutures: Between the bones of the skull (ex. Lambdoid Suture)
- Syndesmosis: Bones are connected by membrane or ligament (ex. middle radio-ulnar joint)
- Gomphoses: Formed between the roots of the teeth and the bony socket in the maxilla and the mandible through the periodontal ligament. (ex. teeth)
What are the Two Types of Cartilaginous Joints? Describe them and provide an example
- Synchondroses: Bones are linked together by hyaline cartilage. (ex. Sternocostal Joint: first rib and sternum)
- Symphyses: Bones are connected via fibrocartilage disc (ex. Pubic Symphysis)
What are the Main Features of a Synovial Joint? (5)
- Joint Capsule
- Joint (articular) Cavity
- Synovial Membrane
- Synovial Fluid
- Articular Cartilage
What is a Joint Capsule?
- Main Feature of a Synovial Joint
- A fibrous sleeve-like structure that completely invests the joint and is supported by ligaments
What is a Joint (articular) Cavity?
- Main Feature of a Synovial Joint
- A space enclosed by the fibrous capsule
What is a Synovial Membrane?
- Main Feature of a Synovial Joint
- Lines the internal joint surface outside the immediate articular surface of the bone.
- The space enclosed by the synovial membrane is called the synovial cavity
What is Synovial Fluid?
- Main Feature of a Synovial Joint
- A watery fluid secreted by the synovial membrane and contained within the synovial cavity.
- Nourishes and lubricates the articular cartilage
What is an Articular Cartilage?
- Main Feature of a Synovial Joint
- A thin layer of hyaline cartilage or fibrocartilage that covers the articular surface of bones.
What are the Associated Structures of a Synovial Joint? (5) and what do they do?
Associated Structures - Ligaments - Bursae - Menisci - Labrums - Intra-articular Discs Functions - Support the joint and facilitate the movement of soft tissue surrounding the joint
What are Ligaments? What are the 2 types of ligaments and how do they differ?
Ligaments
- Thick bands of dense connective tissue that join the bones together
Types
- Intrinsic Ligaments: Thickened part of the fibrous capsule
- Extrinsic Ligaments: not part of the fibrous capsule. Can be inside (intracapsular) or outside (extracapsular) of the joint cavity
What is a Bursae? and where might it be found?
Bursae
- An Associated Structure of a Synovial Joint
- Small sacs of connective tissue separate the structures around the joints.
- Lined by the synovial membrane and filled with synovial fluid
Found
- Between muscles and the joint capsule
- Knee or Elbow
What are Menisci? Where can they be found?
Menisci
- Associated structure of a synovial joint
- Incomplete fibrocartilage rings attached to the articular surface of Tibia to increase joint congruency
Found
- In the Knee Joint, on the Proximal end of the Tibia
What are Labrums? Where can they be found?
Labrums
- Associated structure of a synovial joint
- Fibrocartilage rings attached to the circumference of ball-socket joint cavities
- Increases depth of cavity and increases congruency
Found
- Glenoid Cavity (Shoulder Joint)
- Acetabulum (Hip Joint)
What are Intra-articular Discs? Where can they be found?
Intra-articular discs
- Cushions of fibrocartilage are found within joints to absorb shock and increase congruency
Found
- Found in the Temporomandibular Joint (Jaw)
What are the Four Classifications of Synovial Joints?
- Non-axial Joints
- Uniaxial (monoaxial) Joint
- Biaxial Joints
- Multiaxial Joint
Describe a Non-axial Joint? What kind of joints fit this category?
Non-Axial Joint - Synovial joint that does not move in a direct plane - Sliding or gliding movement only Joints - Planar (Gliding) Joints
Describe a Planar (Gliding) Joint. What is an example?
Panar (Gliding) Joint
- Non-Axial Synovial Joint
- Flat articular Surface
- Performs a gliding movement
Example
- Intercarpal Joints (joints between carpals)
- Intertarsal Joints (joints between tarsals)
What is a Uniaxial (monoaxial) Joint? What kind of joint fits this category?
Uniaxial (monoaxial) Joint - Synovial Joint - Moves in one anatomical plane Joints - Hinge Joint - Pivot Joint
Describe a Hinge Joint and provide an example of one
Hinge Joint
- A Uniaxial Synovial Joint
- A convex articular surface meets a concave articular surface
- Designed for flexion/extension movements
Examples
- Elbow Joint (Ulna and Humerus)
Describe a Pivot Joint and provide an example
Pivot Joint - A Uniaxial Synovial Joint - A round articular surface fits a relatively shallow concave articular surface - For rotational movements Example - Proximal Radioulnar Joint
