joints
DESCRIPTION
Joints. Articulations of bones Functions of joints All joints hold bones together Allow for mobility Ways joints are classified Functionally Structurally. Functional Classification of Joints. Synarthroses Immovable joints Amphiarthroses Slightly moveable joints Diarthroses - PowerPoint PPT PresentationTRANSCRIPT
Articulations of bones Functions of joints
◦ All joints hold bones together◦ Allow for mobility
Ways joints are classified◦ Functionally◦ Structurally
Joints
Synarthroses◦ Immovable joints
Amphiarthroses◦ Slightly moveable joints
Diarthroses◦ Freely moveable joints
Functional Classification of Joints
Fibrous joints◦ Generally immovable
Cartilaginous joints◦ Immovable or slightly moveable
Synovial joints◦ Freely moveable
Structural Classification of Joints
[Insert Table 5.3 here]
Summary of Joint Classes
Table 5.3
Bones united by fibrous tissue Example:
◦ Sutures◦ Syndesmoses
Allows more movement than sutures Example: Distal end of tibia and fibula
Fibrous Joints
Bones connected by cartilage Example:
◦ Pubic symphysis Intervertebral joints
Cartilaginous Joints
Articulating bones are separated by a fibrous articular joint cavity
Synovial fluid is found in the joint cavity
Synovial Joints
Include hip, knee, elbow joints
http://www.argosymedical.com/Skeletal/samples/animations/Synovial%20Joints/index.html
Articular cartilage (hyaline cartilage) covers the ends of bones
A fibrous articular capsule encloses joint surfaces
A joint cavity is filled with synovial fluid Ligaments reinforce the joint
Features of Synovial Joints
Bursae—flattened fibrous sacs◦ Lined with synovial membranes◦ Filled with synovial fluid◦ Not actually part of the joint
Tendon sheath◦ Elongated bursa that wraps around a tendon
Ligamento reinforce articular capsule
Structures Associated with the Synovial Joint
http://www.argosymedical.com/Skeletal/samples/animations/Aging%20Bone/index.html
http://www.argosymedical.com/Skeletal/index.html
The Synovial Joint
Figure 5.29
Reinforce articular capsule Covers the ends of bones
Lines the articular capsule
Fluid filled synovial membrane sacs
Types of Synovial Joints
Figure 5.30a–cUlna / RadiusAtlas/axis
Elbow (humerus /ulna)Interphalange (between phalanges)
Intercarpal (between carpal bones)
Sliding movements in one or two planes(uni-or biaxial
Allows movement in one plane (uniaxial)
uniaxial
Types of Synovial Joints
Figure 5.30d–f
Metacarpal bones/ proximal phalanges (knuckles)Forearm bones/ wristSkull/ vertebral columnWrist joint
Shoulder jointHip joint
biaxialbiaxial
Thumb metacarpal and trapezium (a carpal)
multiaxial
Hip joint is more stable than the knee joint
◦ Hip Is a multiaxial joint Allows movement in all directionsKnee
allows movement in one plane (uniaxial)
Hip vs Knee Joint
Five Golden Rules of Skeletal Muscle Activity
Table 6.2
Movement is attained due to a muscle moving an attached bone
Muscles are attached to at least two points◦ Origin
Attachment to a moveable bone◦ Insertion
Attachment to an immovable bone
Muscles and Body Movements
Muscles and Body Movements
Figure 6.12
Flexion◦ Decreases the angle of the joint◦ Brings two bones closer together◦ Typical of hinge joints like knee and elbow
Extension◦ Opposite of flexion◦ Increases angle between two bones
Types of Ordinary Body Movements
Types of Ordinary Body Movements
Figure 6.13b
Rotation◦ Movement of a bone
around its longitudinal axis
◦ Common in ball-and-socket joints
◦ Example is when you move atlas around the dens of axis (shake your head “no”)
Types of Ordinary Body Movements
Abduction◦ Movement of a limb away
from the midline
Adduction◦ Opposite of abduction◦ Movement of a limb toward
the midline
Types of Ordinary Body Movements
Circumduction◦ Combination of flexion, extension, abduction, and
adduction◦ Common in ball-and-socket joints
Types of Ordinary Body Movements
Dorsiflexion◦ Lifting the foot so that the superior surface
approaches the shin Plantar flexion
◦ Depressing the foot (pointing the toes)
Special Movements
Inversion◦ Turn sole of foot medially
Eversion◦ Turn sole of foot laterally
Special Movements
Supination◦ Forearm rotates laterally so palm faces anteriorly
Pronation◦ Forearm rotates medially so palm faces
posteriorly
Special Movements
Opposition◦ Move thumb to touch the tips of other fingers on
the same hand
Special Movements
Bursitis—inflammation of a bursa usually caused by a blow or friction
Tendonitis—inflammation of tendon sheaths Arthritis—inflammatory or degenerative
diseases of joints◦ Over 100 different types◦ The most widespread crippling disease in the
United States
Inflammatory Conditions Associated with Joints
Osteoarthritis◦ Most common chronic arthritis◦ Probably related to normal aging processes◦ Softening, fraying and eventual breakdown of
cartilage leading to bone spurs (excess bone tissue) Rheumatoid arthritis
◦ An autoimmune disease—the immune system attacks the joints
◦ Symptoms begin with bilateral inflammation of certain joints
◦ Often leads to deformities
Clinical Forms of Arthritis
Gouty arthritis◦ Inflammation of joints is caused by a deposition of
uric acid crystals from the blood◦ Can usually be controlled with diet
Clinical Forms of Arthritis
Osteoporosis◦ Bone-thinning disease afflicting
50% of women over age 65 20% of men over age 70
◦ Disease makes bones fragile and bones can easily fracture
◦ Vertebral collapse results in kyphosis (also known as dowager’s hump)
◦ Estrogen aids in health and normal density of a female skeleton
Skeletal Changes Throughout Life
Skeletal Changes Throughout Life
Figure 5.34
Skeletal Changes Throughout Life
Figure 5.35
Dislocation of joint A dislocation is a separation of two bones where they meet at a joint. A dislocated bone is no longer in its normal position, which may result in damage to ligaments, nerves, and blood vessels.
Dislocation of the shoulder joint is common and occurs when the top part of arm bone slips out of its socket
Radial dislocation may be caused by a sudden pull on a child's arm or hand. For first aid, immobilize the arm and take the child to the doctor's office or emergency room.