Chapter 8 (Lecture Objective 5) Flashcards
(12 cards)
How are the joints classified?
Structure and function (movement at joints)
Structural classifications of joints, and major classifications?
- Fibrous – connected by fibrous tissue
- Cartilaginous – connected by cartilage
- Synovial – fluid-filled joint cavity
Functional classifications of joints, and what characterizes each?
- Synarthoses – immovable
- Amphiarthroses – slightly movable
- Diarthroses – freely movable
Three types of fibrous joints, and what characterizes each?
- Sutures – only between bones of the skull
- Syndesmoses – bones are exclusively connected by ligaments, cords, bands of fibrous tissue
- Gomphoses – peg-in-socket fibrous joint
Characteristics of amphiarthritic joints?
Slightly movable joint, surfaces of bones are connected by ligaments or cartilage
6 different types of synovial joints.
- Plane (nonaxial)
- Hinge (uniaxial)
- Pivot (uniaxial, rotation permitted)
- Condylar (biaxial, angular movement in 2 planes)
- Saddle (biaxial, freer movement)
- Ball-and-socket (multiaxial, rotation movement)
Types of arthritis (3)
- Rheumatoid
- Gouty
- Osteoarthritis
Functions labrum, bursa
- Labrum – fibrocartilage attached to rim of shoulder socket, keeps ball of joint in place
- Bursa – flattened fibrous sacs lined with synovial membrane, act as lubricating layer in joints
Structural, functional classification:
TMJ, atlantoaxial,
intervertebral, AC, SI, and ankle (tibia, fibula, talus) joints
- TMJ – Synovial, modified hinge; diarthrotic, gliding and uniaxial rotation
- Atlantoaxial – Synovial, pivot; diarthrotic, uniaxial
- Intervertebral - Cartilaginous/synovial; amphiarthrotic/diarthrotic
- AC – Synovial, plane; diarthrotic, gliding and rotation of scapula
- SI – Synovial, plane; diathrotic in child, amphiarthrotic in adult
- Ankle – Synovial, hinge; diarthrotic, uniaxial
Describe the following movements: flexion, extension, abduction, adduction, supination, pronation,
dorsiflexion, plantar flexion, inversion, and eversion.
- Flexion – bending movement, decreases the angle of the joint and brings articulating bones closer
- Extension – bending movement, increases the angle of the joint and brings articulating bones further
- Abduction – movement of limb away from midline, along frontal plane
- Adduction – movement of limb toward midline
- Supination – rotating forearm so palms face anteriorly or superiorly
- Pronation – forearm rotates medially and palms face posteriorly or inferiorly
- Dorsiflexion – lifting the foot so that its superior surface approaches the shin
- Plantar flexion – depressing the foot and flattening toes
- Inversion – sole of the foot turns medially
- Eversion – sole of the foot faces laterally
Major structures of the shoulder joint
- Glenoid labrum – 1/3 size of humeral head, provides little stability
- Coracohumeral ligament – provides only strong thickening of capsule, helps support weight of upper limb
- Glenohumeral ligaments – strengthen the front of the capsule somewhat, are weak or absent
- Rotator cuff – encircles shoulder joints and blends with articular capsule
Why do shoulder separations occur so easily?
Shoulder reinforcements are weakest anteriorly and inferiorly, the humerus tends to dislocate in the
forward and downward direction
