Joints!
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3 types of joints if we classify by function
(i.e., by the degree of movement
possible):
1. Diarthroses (Synovial)
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Freely moveable joints
Shoulder, knee, hip, elbow, interphalangeal, tarsal,
and carpal joints
2. Amphiarthroses (Cartilaginous) Amphi-slightly
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Slightly moveable joints
Intervertebral discs, costosternal joints, pubic
symphysis
3. Synarthroses (Fibrous) Syn--together
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Joints with little or no movement
Skull sutures, teeth in sockets, 1st costosternal joint.
Joint Classification

We can also classify
joints by structure:
1. Synovial joints:
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Bones separated
by a joint cavity;
lubricated by
synovial fluid;
enclosed in a
fibrous joint
capsule.
Shoulder, hip,
elbow, knee,
carpal,
interphalangeal
How would we classify these
joints functionally?
Joint Classification
2. Fibrous joints:

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Bones held
together by
collagenous fibers
extending from the
matrix of one bone
into the matrix of
the next.
No joint cavity
Little or no
movement occurs
between bones
Skull sutures, teeth
joints, distal
radioulnar joints &
tibiofibular joints
Types of Fibrous Joints
There are three types of fibrous joint:
 Sutures—very tight articulations between
adjacent bones. Only found in the skull.
 Syndesmosis—the bones are held together
by strong, fibrous connective tissue. Bones
may be held together by ligaments or
interosseous membranes. Very little
movement is possible.
 Gomphosis—a unique peg-and-socket joint at
which no movement occurs. Only found
between the permanent teeth and the maxilla.
Joint Classifications
3. Cartilaginous joints:


Bones held together by cartilage; no joint cavity
Epiphyseal plates of long bones, costosternal
joints, pubic symphysis, intervertebral discs
Types of Cartilaginous Joints
There are two types of cartilalaginous joints:
1. Symphysis—Examples include the
intervertebral discs and the symphysis pubis.
2. Synchondrosis—Examples include the
epiphyseal growth plate in a long bone.
Herniated Disc
 Disc Surgery Herniated - Learn about
Herniated Disc Surgery
 YouTube - Back Surgery for Disc
Herniation
Structure and Function
 Joints are
designed for their
function.
 Let’s look at
sutures as our 1st
example:
 What function
do you suppose
sutures are
designed for?
Structure and Function
 Let’s look at some symphyses.
 What kind of joint is a symphysis? What kind of
movement is possible?
 Name a symphysis! (an obvious one is in the picture)
 What connects the bones in these joints?
Structure and Function


Now let’s talk about
synovial joints.
 How do they differ
from the previous 2?
5 main structural
characteristics:
1. Articular cartilage
 What kind of
cartilage is it? (H _
_____)
 Where do we find
it?
 What does it do?
Structure and Function
2. Articular capsule
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2 layered. Surrounds both
articular cartilages and the
space btwn them.
External layer is made of
dense irregular CT & is
continuous w/ the
perisoteum.
Inner layer is a synovial
membrane made of loose
connective tissue.

It covers all internal joint
surfaces except for those
areas covered by the
articular cartilage.
Structure and Function
3.
Joint (Synovial) Cavity

4.
The potential space within
the joint capsule and
articular cartilage
Synovial Fluid

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A small amount of slippery
fluid occupying all free
space w/i the joint capsule
Formed by filtration of
blood flowing through
capillaries in the synovial
membrane
Synovial fluid becomes
less viscous as joint
activity increases.
Structure and Function
5.
Reinforcing
Ligaments
 What kind of tissue
are they?
 What do you
suppose their
function is?
 Double-jointedness results from
extra-stretchy
ligaments and joint
capsules. Is this
necessarily a good
thing?
Other Synovial Structures
 The knee and hip joints
have cushioning fatty
pads btwn the fibrous
capsule and the synovial
membrane or bone.
 Discs of fibrocartilage
(i.e., menisci) which
improve the fit btwn bone
ends, thus stabilizing the
joint.
 Found in the knee, jaw, and
sternoclavicular joint.
 Bursae are basically bags
of lubricant - fibrous
membrane bags filled w/
synovial fluid. Often
found where bones,
muscles, tendons, or
ligaments rub together.
Synovial Joints
 YouTube - Types of Synovial Joints
Types of
Synovial Joints
1.
Plane joints
 Articular surfaces are flat and
allow short slipping or
gliding movements.
 Intercarpal and intertarsal
joints
2. Hinge joints
 A cylindrical projection of
one bone fits into a troughshaped surface on another
(like a hotdog in a bun)
 Movement resembles a door
hinge.
 Elbow joint – ulna and
humerus; Interphalangeal
joints
Type of
Synovial Joints
3.
Pivot joints
 Rounded end of one bone
protrudes into a ring
formed by another bone or
by ligaments of that bone.
 Proximal radioulnar joint
 Atlas-axial joint
4.
Condyloid joints
 Oval articular surface of
one bone fits into a
complementary depression
on another.
 Radiocarpal joints
 Metacarpophalangeal
joints
Types of
Synovial Joints
5. Saddle joints
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Each articular surface has
convex and concave areas.
Each articular surface is
saddle-shaped.
Carpometacarpal joints of the
thumbs.
6. Ball-and-Socket joints
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Spherical or semi-spherical
head of one bone articulates
with the cuplike socket of
another.
Allow for much freedom of
motion.
Shoulder and hip joints.
The Knee
 Largest and most complex
diarthrosis in the body.
 Primarily a hinge joint, but
when the knee is flexed, it is
also capable of slight
rotation and lateral gliding.
 Actually consists of 3 joints:
 Patellofemoral joint
 Medial and lateral
tibiofemoral joints
 The joint cavity is only
partially enclosed by a
capsule – on the medial,
lateral, and posterior sides.
 The lateral and medial
condyles of the femur
articulate with the
lateral and medial
condyles of the tibia.
 Between these
structures, we have the
lateral and medial
menisci.
 Anteriorly, the patellar
ligament binds the
tibia to the inferior
portion of the patella.
The superior portion
of the patella is then
connected to the
quadriceps femoris
muscle
The Knee
 At least a dozen
bursae are
associated with the
knee.
 Multiple ligaments
are present.
 The fibular collateral
ligament extends
from the lateral
epicondyle of the
femur to the head of
the fibula.
 The tibial collateral
ligament connects
medial epicondyle of
the femur to the
medial condyle of the
tibial shaft and is also
fused to the medial
meniscus.
 Both of these
ligaments prevent
excessive rotation
The Knee
 The anterior and
posterior cruciate
ligaments are also very
important.
 ACL connects the anterior
intercondylar area of the
tibia to the medial side of
the lateral femoral condyle.
 Prevents forward sliding of
the tibia and
hyperextension of the knee.
 PCL connects the posterior
intercondylar area of the
tibia to the lateral side of
the medial femoral
condyle.
 Prevents backward
displacement of the tibia or
forward sliding of the femur.
The Knee
Clinical
Conditions
 Arthritis describes about
100 different types of
inflammatory or
degenerative joint
diseases.
 Osteoarthritis
 Most common arthritis.
 Normal joint use prompts
the release of cartilagedamaging enzymes. If
cartilage destruction
exceeds cartilage
replacement, we’re left with
roughened, cracked, eroded
cartilages.
 Eventually bone tissue
thickens and forms spurs
that can restrict movement.
 Most common in C and L
spine, fingers, knuckles,
knees, and hips.
 Rheumatoid arthritis
 Chronic inflammatory
disorder
 Marked by flare-ups
 Autoimmune disease.
 Body creates antibodies
which attack the joint
surfaces
 The synovial membrane can
inflame and eventually
thicken into a pannus – an
abnormal tissue that clings
to the articular cartilage.
 The pannus erodes the
cartilage and eventually scar
tissue forms and connects
the 2 bone ends. This scar
tissue can later ossify,
fusing the bones together.
This is known as ankylosis.
Clinical
Conditions
Clinical
Conditions
 Gouty arthritis
 When nucleic acids are metabolized
uric acid is produced. Normally uric
acid is excreted in the urine.
 If blood [uric acid] rises due to
decreased excretion or increased
production, it may begin to form
needle-shaped crystals in the soft
tissues of joints.
 Inflammation ensues causing painful
arthritis.
Gout Risk Factors
Risk factors for developing gout include obesity,
excessive weight gain, especially in youth,
moderate to heavy alcohol intake, high blood
pressure, and abnormal kidney function. Certain
drugs, such as thiazide diuretics
(hydrochlorothiazide [Dyazide]), low-dose aspirin,
niacin, cyclosporine, tuberculosis medications
(pyrazinamide and ethambutol), and others can
also cause elevated uric-acid levels in the blood
and lead to gout. Furthermore, certain diseases
lead to excessive production of uric acid in the
body. Examples of these diseases include
leukemias, lymphomas, and hemoglobin
disorders.
Bursitis
Bursitis is the painful inflammation or irritation of
the bursa. The bursa is a soft, fluid-filled sac that
covers and cushions the movement between the
bones, tendons and muscles near the joints.
Bursitis usually occurs under the shoulder
muscles, at the elbows (called epitrochlear
bursitis or "tennis elbow"), the hip sockets
(called trochanteric bursitis), heel bones (called
retrocalcaneal bursitis) or the kneecaps (called
infrapatellar bursitis or "housemaid's knee"). It
can also occur in the buttocks (called
ischiogluteal bursitis) or the thigh (called
trochanteric bursitis).
Buristis
 http://www.livestrong.com/video/1662bursitis-health-byte/
Causes of Bursitis
Most commonly, bursitis is caused by trauma, infection,
and crystal deposits. Some specific factors include:
Overuse or injury to the joint areas from playing or
working
Incorrect posture at work or rest, or poor conditioning
before exercise or playing sports
An abnormal or poorly positioned joint or bone (such as
leg length differences or arthritis in a particular joint)
that stresses soft tissue structures.
Sometimes in association with other diseases or
conditions, such as rheumatoid arthritis, gout,
tuberculosis or psoriatic arthritis
Staphylococcal or other (bacterial) infection
Symptoms of Bursitis
Symptoms of bursitis may include:
Pain that increases with movement of
joint
Tenderness of joint
Limited movement in the affected areas
Swelling and redness in affected areas
Treatments of Bursitis
Treatment for bursitis includes applying the R.I.C.E therapy, protecting
the area, and anti-inflammatory drugs.
It can help to protect bursae close to the skin, such as the ankles and
knees, with padding. Additionally, deep-heat therapy (diathermy) can also
relieve the discomfort and inflammation of bursitis.
Anti-inflammatory medications, such as aspirin or over-the-counter
nonsteroidal drugs (NSAIDs), such as ibuprofen, naproxen, or
indomethacin can often be helpful. If the cause of the bursitis is bacterial,
antibiotics will be administered.
If the inflammation does not respond to the R.I.C.E. therapy and
medications, surgical drainage (aspiration) of fluid from the bursa and the
injection of corticosteroids into the bursa is an alternative treatment.
Surgical removal of the bursa is a possibility for chronic bursitis.
With adherence to treatment, bursitis usually subside in seven to 14 days.