Chapter 9: Articulations Flashcards
Articulations (joints)
Sites where two or more bones meet.
What are the functions of articulations?
Hold bones together and allows for mobility
How are joints classified?
Structurally and functionally
How are joints classified structurally?
Fibrous- dense connective tissue
Cartilaginous- Some type of cartilage
Synovial- fluid-filled cavity surrounded by a capsule.
What are the three different ways joints are classified functionally?
Synarthroses
Amphiarthroses
Diarthroses
Synarthroses
Without movement
These joints are either fibrous or cartilaginous
Amphiarthroses
Slight movement
Either fibrous or cartilaginous
Diarthroses
Freely moveable
Synovial joints
Fibrous Structural Joints
Synarthrotic
Extremely strong joints located where movement between the bones must be prevented.
What are some types of fibrous structural joints?
Sutures- between the bones of the skull. Allow for growth. Becomes synostoses (bony junction)
Syndesmoses (ligaments) between bones, like the distal connection between the tibia and fibular and interosseous membrane.
Gomphoses- peg-in-socket, periodontal ligament around the tooth.
Cartilaginous Joints
Made of hyaline cartilage
Synarthrotic or Amphiartrotic
What are some types of cartilaginous joints?
Synchondrosis -hyaline cartilage in the epiphyseal plates and between the first rib and the manubrium of the sternum. (synarthrotic)
Symphyses - hyaline cartilage fused to an intervening pad of fibrocartilage. Shock absorber. Designed for strength and flexibility. (Amphiarthrotic) in intervertebral joints and pubic symphysis.
Synovial Joints
Articulating bones are separated by a fluid-containing joint cavity.
Freely moveable
All limb joints are synovial joints.
What is the general structures of synovial joints
Articular cartilage- covers articulating surfaces.
Articular Capsule- two layered capsules surround the joint.
Synovial fluid - lubrication, nutrient distribution, and shock absorption.
Reinforcing Ligaments and Tendons- localized thickening that supports, strengthen, and reinforce synovial joints (ligaments) and stabilize the joint (tendons)
What are the friction-reducing structures associated with synovial joints?
Bursae- small, thin, fluid-filled pockets in connective tissue that reduce friction and act as shock absorbers that contain synovial fluid.
Tendon sheaths- Tubular bursae surround tendons where they cross bony surfaces.
Gliding
Two opposing surfaces glide past each other.
Angular
Increase or decrease the angle between two bones.
Flexion, extension, hyperextension, abduction, and circumduction and rotation.
Rotational
Turning around the longitudinal axis of the body or the limb.
Such as rotating your head around or rotating your leg.
What are the types of shapes or synovial joints?
Plane
Hinge
Pivot
Condyloid
Saddle
Ball-and-socket
Plane Joint
Articular flattened face surfaces slide across one another.
Only very slight movement.
Gliding
Nonaxial
Examples: end of clavicles and between carpal and tarsals.
Hinge Joint
Cylindrical projections of one bone fit into a through-shaped surface on another.
Permits angular motion.
Uniaxial
Examples: elbow, knee, ankle, and interphalangeal joints.
Pivot Joints
Rounded end of one bone protrudes into a “sleeve’ or ring composed of the bone of another.
Permits only rotation
Uniaxial
Example: joint between the axis and the atlas, and the proximal radioulnar joint.
Condyloid Joint
Oval articular surface of a bone fits into a complementary depression in another.
Angular motion occurs in two planes.
Biaxial
Examples: radiocarpal joints and metacarpophalangeal joints.
Saddle Joint
Articular faces that resemble saddles. Each face is concave on one side and convex on the other.
Opposing faces nest together.
Permits angular motion, including circumduction but prevents rotation.
Biaxial
Examples: carpometacarpal joint at the base of the thumb.
Ball-and-socket Joint
The round head of one bone nests in a cup-like depression.
Multiaxial
Examples: shoulder and hip joint.
What kind of joints are knee and elbow?
Hinge joints
What are the three joints in the knee?
Femoropatellar joint
Medial and lateral tibiofemoral joints.
What are the tendons and ligaments of the knee joints?
Tendon of the quadriceps femoris muscle
Lateral and medial patellar retinacula.
Patellar Ligament
Fibular and tibial collateral ligaments.
Anterior Cruciate Ligament (ACL)
Prevents forward displacement of the tibia.
Posterior Cruciate Ligament
Prevents backward displacement of the tibia.
Menisci
Semilunar cartilages prevent side-to-side rocking of the femur on tibia.
Medial and Lateral Menisci
What are the two common injuries to the knee?
Lateral blows to extended knee- tear tibial collateral ligament, medial meniscus and ACL.
Torn Anterior Cruciate Ligament-
Heal poorly, occurs when there is a sudden change in direction while running.
What are the ligaments of the elbow?
Ulnar and radial collateral ligaments - prevent side-to-side movement.
Annular ligament- surrounds the head of the radius. Supination and pronation.
Temporomandibular Joint
Modified hinge joint.
Mandibular condyle articulates with the mandibular fossa on the temporal bone.
What types of movement does the temporomandibular joint make?
Gliding, hinge, and side to side.
What are the two important parts of the temporomandibular joint?
Articular Disc- made of fibrocartilage, divides the joint into two compartments. Superior (Protraction and retraction) and Inferior (depression and elevations) Lateral ligament- strengthen TMJ laterally. Prevent posterior dislocation.
Translation of the temporomandibular joint
Allows one to open the mouth wider to spread the upper and lower teeth
The head of the mandible and articular disc move forward until the head lies under the articular tubercle.
Dislocation of the temporomandibular joint
Heads of the mandible can dislocate anteriorly out of alignment with the mandibular fossa.
Jaw “locked” open
Posterior dislocation is prevented by lateral ligament.
What are the five ligaments of the shoulder or glenohumeral joint?
Coracohumeral, glenohumeral, coracocrominal, coracoclavicular, acromioclavicular ligaments.
Tendon of the long head of biceps
Travels through the intertubercular groove and secures the humerus to the glenoid cavity.
Rotator Cuff
4 short muscles- supraspinatus, infraspinatus, subscapularis and teres minor.
Across and surround the joint.
Holds the large head of humerus in a smaller and shallow glenoid cavity of scapula.
What are the ligaments in the hip joint?
Iliofemoral ligament (y-shaped, strongest ligament, prevent hyperextension)
Pubofemoral (orevents over-abduction of hip)
Ichiofemoral ligament (weakest ligament of the three, located posteriorly)
