Download Chapter 8 Joints

Chapter 8
Joints
Quiz Picture p. 220
Quiz Picture p.222
Stability of Synovial Joints
• Articular Surfaces- only a minor
role
• Ligaments- only a minor role
• Muscle Tendons- most important
stabilizing force at a joint
Types of Movement at
Synovial Joints
• Nonaxial- slipping movements only
• Uniaxial- movement in only 1 plane
• Biaxial- movement in 2 planes
• Multiaxial- movement in 3 planes
Why Movement Occurs
• Each skeletal muscle is attached in
at least 2 places to bone or
connective tissue. Movement occurs
with contraction of muscle across
joints.
• Origin-attachment to immobile bone.
• Insertion-attachment to mobile bone
Types of Movement
• Gliding (nonaxial)- bones slip past
each other; no angular movement
occurs
Movement between carpals, tarsals,
and articular processes of vertebrae
Types of Movement
• Angular- several different types
– Flexion- decrease the angle of a joint
– Extension- increase the angle of a joint
– Dorsiflexion (foot)- foot toward head
– Plantarflexion (foot)- foot away from
head
– ABduction- limb away from midline
– ADduction- limb toward midline
Types of Movement
- Circumduction- limb traces a
cone/circle in space
- Rotation- turning a bone around its
own long axis
Special Types Movement
• Suppination- palm up
• Pronation- palm down
• Inversion- foot turns in (sprained
ankle)
• Eversion- foot turns out
Special Types Movement
•
•
•
•
•
Protraction- bone forced forward
Retraction- bone forced backward
Elevation- lift superiorly
Depression- drop inferiorly
Opposition- thumb to tips of fingers
on same hand
Types of Synovial Joints
• Plane Joints- flat articular surfaces;
allow only gliding movements; only
nonaxial joints; intercarpal,
intertarsal, and intervertebral joints
• Hinge Joints- the rounded end of
one bone fits into a space on
another bone; uniaxial joint; elbow
and interphalangeal joints
Types of Synovial Joints
• Condyloid Joints- the articulating
surfaces are oval; biaxial joint
movement; radiocarpal and
metaphalangeal joints are examples
• Saddle Joints- articular surfaces
have concave and convex areas;
biaxial movement; carpometacarpal
joints of thumbs
Types of Synovial Joints
• Pivot Joints- the rounded end of
one bone protrudes into an opening
of another or into a ligament
• Ball and Socket Joints- only two in
the body; the shoulder and the hip;
freely mobile; most versatile joints
Knee Joint
• Largest, most complex joint of body
• articular capsule sides and back of
joint
• highly susceptible to injuries due to
carrying body weight
• horizontal force injuries are the worst
Shoulder
• One of only 2 ball and socket joints
in the body
• humeral head fits into glenoid cavity
• lots of flexibility with a loss of
stability
• location of the rotator cuff
Hip
• ball and socket joints in the body
• femoral head fits into the deep
acetabulum of the coxal bone
• lots of stability but not as much
flexibility as the shoulder
Elbow
• hinge joints in the body
• uniaxial movement
• joint contains fat pad
Injuries
• Torn ligaments
• Bursitis
• Tendonitis
Arthritis
• Osteoarthritis – most common
• Rheumatoid - autoimmune
• Gouty – diet, uric acid
Rheumatoid Arthritis