Transcript Chapter 8 Joints

Chapter 8
Joints
J.F. Thompson, Ph.D. & J.R. Schiller, Ph.D. & G. Pitts, Ph.D.
Classification of Joints
Table 8.1 - Summary of Joint Classes
Structural
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Fibrous - bones joined by fibrous connective tissue;
no joint cavity
Cartilaginous - bones joined by cartilage; no joint
cavity
Synovial - bones separated by fluid filled cavity
Functional
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Synarthroses - non-movable
Amphiarthroses - slightly movable
Diarthroses - freely movable
Fibrous Joints
 Suture - wavy
border with dense
fibrous connective
tissue which
penetrates into both
bone
 Syndesmosis connected by a
ligament
 Gomphosis - peg in
a socket (teeth)
Cartilaginous Joints
 Synchondroses
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hyaline cartilage
epiphyseal plate
• most limb bones

most ribs to sternum
 Symphyses
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fibrocartilage
pelvis, vertebrae
Synovial Joints
 General Structure
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articular cartilage
synovial (joint) cavity
articular capsule
synovial fluid
reinforcing ligaments
meniscus – a
fibrocartilage pad, e.g., at
the tempero-mandibular
joint (TMJ) and at the
tibio-femoral (knee) joint
Synovial Joints
 Bursae - flattened sacs filled with synovial fluid
 Tendon sheath - elongated bursa which wraps around
a tendon
Synovial Joints
 Gliding (plane) joint
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flat planes gliding
over each other
intercarpal and
intertarsal joints
Synovial Joints
 Hinge

cylindrical projection
fits into a notch

ulna and humerus

tibia and femur

interphalangeal joints
Synovial Joints
 Pivot
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rounded end of one
bone protrudes into
sleeve or ring of bone
or ligaments
atlas (C1) and dens
of the axis (C2)
proximal radio-ulnar
joint
Synovial Joints
 Condyloid
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rounded (convex)
articulating surface of
one bone fits into
concave depression on
the other bone
radio-carpal joints
metacarpal-phalangeal
joints
Synovial Joints
 Saddle
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each articular surface
has both convex and
concave areas
carpo-metacarpal joint
of the thumb
special case of a
condyloid joint
Synovial Joints
 Ball and Socket
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spherical or
hemispherical head of
one bone articulates
with cuplike socket
provides greatest
rotational flexibility
shoulder
hip
special case of a
condyloid joint which
is capable of
circumduction
Know the Terminology for Types of Motions in Your Lab Guide
Gliding
Rotation
Flexion/Extension
Abduction/Adduction
Circumduction
Special Movements
Reviewed in lab
Factors Influencing Joint Stability
Articular surfaces – shape and condition are
important for smooth functioning of the joint
Ligaments – dense regular fibrous connective
tissue which will only stretch ~6% before
tearing
Muscle Tone
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most important
tone - resting activity – some minimal level of
contraction operating at all times
muscles, tendons, and ligaments are supplied with
sensory nerve endings for feedback control of limb
and body position and posture
Sagittal View of Knee Joint
 The knee joint is
a classic site for
repeated injuries.
 Since cartilage
does not repair
well, the
cumulative effect
of multiple
traumas is to
permanently
weaken the joint.
 Anterior view.
Knee joint relationships with some associated muscles
• Ligaments and
tendons
contribute to joint
stability.
• Physical
therapists and
practitioners of
sports medicine
must become
expert in the
anatomy of the
musculoskeletal
system.
A common knee injury
A blow from the
side forces the
bones to move
in a direction
incompatible
with the joint’s
design.
Ligaments are
not flexible so
they tear. They
can repair with
time. Cartilage
repair will be
minimal.
Anterior Cruciate Ligament (ACL) Injury
ACL torn above →
& repaired below;
screws stabilize
the repair. 
Arthritis
More than 100 different types of inflammatory
or degenerative joint diseases
Most common crippling diseases in the U.S.
Symptoms – pain, stiffness, and swelling of
joint(s)
Acute forms are caused by bacteria and are
treated with antibiotics
Chronic forms include osteoarthritis (OA),
rheumatoid arthritis, and gouty arthritis
After the End of Chapter 8,
You Will Find Some
Additional Slides with More
Detailed Information on Certain
Topics for Your Review
End Chapter 8
Gliding Movement
Figure 8.5a
Angular Movement
Rotational Movement
Special Movements

Ligaments and Tendons of Knee
all contribute to stability
many contribute to fibrous
capsule
Sprains
The ligaments reinforcing a joint are stretched
or torn
Partially torn ligaments slowly repair
themselves
Completely torn ligaments require prompt
surgical repair
Cartilage Injuries
The snap and pop of overstressed cartilage
Common aerobics injury
Repaired with arthroscopic surgery
Dislocations
Occur when bones are forced out of alignment
Usually accompanied by sprains, inflammation,
and joint immobilization
Caused by serious falls and are common sports
injuries
Subluxation – partial dislocation of a joint
Inflammatory and Degenerative
Conditions
 Bursitis
 An inflammation of a bursa, usually caused by a blow or
friction
 Symptoms are pain and swelling
 Treated with anti-inflammatory drugs; excessive fluid may
be aspirated
 Tendonitis
 Inflammation of tendon sheaths typically caused by overuse
 Symptoms and treatment are similar to bursitis
Developmental Aspects of Joints
By embryonic week 8, synovial joints
resemble adult joints
Few problems occur until late middle age
Advancing years take their toll on joints:
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Ligaments and tendons shorten and weaken
Intervertebral discs become more likely to
herniate
Most people in their 70s have some degree of
OA
Prudent exercise (especially swimming) that
coaxes joints through their full range of
motion is key to postponing joint problems
End Chapter 8
End of extra review slides