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Osteoarthritis
Dr. Vividh Makwana
Joint Replacement and
Orthopedic Surgeon
Osteoarthritis (OA)
• OA is the most common form of
arthritis and the most common
joint disease
• Over 10 million Americans
suffer from OA of the knee alone
• Most of the people who have OA
are older than age 45, and women
are more commonly affected than
men.
• OA most often occurs at the ends
of the fingers, thumbs, neck,
lower back, knees, and hips.
OA
OA is a disease of
joints that affects all of
the weight-bearing
components of the
joint:
•Articular
cartilage
•Menisci
•Bone
Commonly Affects
– Hips
– Knees
– Feet
– Spine
– Hands (Interphalangeal joints)
Uncommonly Affected Joints
•
•
•
•
•
•
•
Shoulder
Wrist
Elbow
Metacarpophalangeal joint
TMJ
SI
Ankle
OA
Nodal osteoarthritis
Note bony
enlargement of distal
and proximal
interphalangeal
joints (Heberden's
nodes and
Bouchard's nodes,
respectively).
OA – Risk Factors
Age
•
Age is the strongest risk factor for OA. Although OA can
start in young adulthood, if you are over 45 years old, you
are at higher risk.
Female gender
•
In general, arthritis occurs more frequently in women than
in men. Before age 45, OA occurs more frequently in men;
after age 45, OA is more common in women. OA of the
hand is particularly common among women.
Joint alignment
•
People with joints that move or fit together incorrectly, such
as bow legs, a dislocated hip, or double-jointedness, are
more likely to develop OA in those joints.
OA – Risk Factors
Hereditary gene defect
•
A defect in one of the genes responsible for the cartilage
component collagen can cause deterioration of cartilage.
Joint injury or overuse caused by physical labor or
sports
•
Traumatic injury (ex. Ligament or meniscal tears) to the
knee or hip increases your risk for developing OA in these
joints. Joints that are used repeatedly in certain jobs may be
more likely to develop OA because of injury or overuse.
Obesity
•
Being overweight during midlife or the later years is among
the strongest risk factors for OA of the knee.
Risk factors –
Conditions that contribute to
osteoarthritis
Risk factors you cannot change
• Family history
of disease
Risk factors you cannot change
• Family history
of disease
• Increasing age
Risk factors you cannot change
• Family history
of disease
• Increasing age
• Being female
Risk factors you can change
• Overuse of the
joint
Risk factors you can change
• Overuse of the
joint
• Major injury
Risk factors you can change
• Overuse of the
joint
• Major injury
• Overweight
Risk factors you can change
• Overuse of the
joint
• Major injury
• Overweight
• Muscle
weakness
Diagnosing osteoarthritis
Medical history
Physical exam
X-ray
Other tests
OA – Symptoms
• OA usually occurs slowly It may be many years before
the damage to the joint
becomes noticeable
• Only a third of people
whose X-rays show
OA report pain or
other symptoms:
– Steady or intermittent pain in a joint
– Stiffness that tends to follow periods of inactivity, such as sleep
or sitting
– Swelling or tenderness in one or more joints [not necessarily
occurring on both sides of the body at the same time]
– Crunching feeling or sound of bone rubbing on bone (called
crepitus) when the joint is used
Osteoarthritis (OA) - Definition
Osteoarthritis may result from wear and tear
on the joint
•The normal
cartilage lining
is gradually
worn away and
the underlying
bone is
exposed.
Two Major Types of OA
• Primary or Idiopathic
– Most common type
– Diagnosed when there is no known cause for
the symptoms
• Secondary
– Diagnosed when there is an identifiable cause
• Trauma or Underlying joint disorder
• Each of these major types has subtypes
Osteoarthritis (OA) - Definition
•The repair mechanisms of tissue absorption and
synthesis get out of balance and result in
osteophyte formation (bone spurs) and bone cysts
A case of the, “Which
came first? The
chicken or the egg?”
OA – Articular Cartilage
Articular cartilage is the main tissue affected
OA results in:
•Increased tissue swelling
•Change in color
•Cartilage fibrillation
•Cartilage erosion down to subchondral bone
OA – Articular Cartilage
OA – Articular Cartilage
A) Normal articular
cartilage from 21-year old
adult (3000X)
B) Osteoarthritic cartilage
(3000X)
The surface changes
alter the distribution
of biomechanical
forces further
triggering active
changes by the
tissue
OA – Articular Cartilage
The cartilage damage causes chondrocyte cloning in an
attempt to restore articular surface (Normal adult
chondrocytes are fully differentiated and do not proliferate)
(A) Normal articular cartilage (B) Osteoarthritic cartilage
OA – Articular Cartilage
Unfortunately, the newly dividing cells do not
differentiate fully and cannot effectively synthesize the
elements needed for matrix maintenance
This results in a net loss of matrix components
•Collagen content stays constant but fibrils are thinner
and more disorganized
- Decreased tensile strength
OA – Articular Cartilage
•Proteoglycan loss
results in an
inability to hold on
to water content:
- Decreased
resistance to
compression –
especially with
repeated stress
OA vs. Aging
Unlike aging, OA is progressive and a significantly
more active process
OA – Overall Changes
Osteoarthritis with lateral osteophyte, loss of articular cartilage and
some subchondral bony sclerosis- X-ray shows loss of joint space
Laboratory findings in OA
• THERE ARE NO DIAGNOSTIC LAB
TESTS FOR OSTEOARTHRITIS
• OA is not a systemic disease, therefore:
– ESR, Chem 7, CBC, and UA all WNL
• Synovial fluid
• Mild leukocytosis (<2000 WBC/microliter)
• Can be used to exclude gout, CPPD, or septic
arthritis if diagnosis is in doubt
Synovial fluid analysis
• Severe, acute joint pain is an
uncommon manifestation of OA
• Clear fluidWBC <2000/mm3
• Normal viscosity
In a NUT SHELL
•Primary etiology of OA remains
undetermined
•Believed that cartilage integrity is
maintained by a balance obtained
from cytokine driven-driven
anabolic and catabolic processes
Differential Diagnosis
• Rheumatoid Arthritis
• Gout
• CPPD (Calcium pyrophosphate crystal
deposition disease)
• Septic Joint
• Polymyalgia Rheumatica
OA – Radiographic Diagnosis
Asymmetrical joint space narrowing from loss of
articular cartilage
The medial (inside) part of the knee is most commonly affected by osteoarthritis.
OA – Radiographic Diagnosis
•Asymmetrical
joint space
narrowing
•Periarticular
sclerosis
•Osteophytes
•Sub-chrondral
bone cysts
OA – Arthroscopic Diagnosis
Arthroscopy allows earlier
diagnosis by demonstrating the
more subtle cartilage changes
that are not visible on x-ray
Normal Articular Cartilage
Ostearthritic degenerated cartilage
with exposed subchondral bone
Epidemiology of OA
• OA of the knee is the leading cause of
chronic disability in the elderly in
developed countries
• In patients over the age of 55:
– Hip OA is more common in men
– IP and 1st MCP OA is more common in women
– Knee OA (with sx) is more common in women
Epidemiology of OA
• In patients under the age of 55:
– Joint distribution of OA is equal between men
and women
• Due to genetics or joint usage?????
– Mother and sister of a woman with DIP OA are
2 & 3 X more likely to have the same
– Racial differences in prevalence and pattern of
joint involvement also point to genetic basis
Epidemiology of OA
•
•
•
•
Age is the most powerful risk factor for OA
Women < 45 years of age: 2% with OA
Women 45-64: 30% with OA
Women >65: 68% with OA
Epidemiology of OA
• There is no convincing data to support an
association between nonspecific
nonprofessional athletic activities and
osteoarthritis
– (excluding major trauma)
• Neither long-distance running nor jogging
has been shown to cause osteoarthritis
Epidemiology of OA
• Obesity is a risk factor for knee (and hand)
osteoarthritis
– In the highest quintile of BMI
• Relative risk of developing OA in the next 36 years
was 1.5 for men and 2.1 for women
• For SEVERE OA, the RR rose to 1.9 for men and
3.2 for women
– Weight loss of 5kg was associated with a 50%
reduction in the odds of developing OA
Epidemiology of OA
• Disability in subjects with knee OA
– More strongly associated with
QUADRICEPS
WEAKNESS
– than with joint pain or radiographic severity
• Demographics associated with increased
likelihood of being symptomatic: women,
unemployed, divorced, poor social support
Watch your weight
Exercise is important
Exercise is important
• Strengthening
Exercise is important
• Strengthening
• Aerobic
Exercise is important
• Strengthening
• Aerobic
• Stretching
Medications lessen the pain
Over-the-counter
Prescription-strength
Prevention of OA
• Physiological effects of physical activity are
most marked in those parts of the body that
are used most during exercise
• Physical activity is the best way to ensure
the maintenance of functional capacity
• Endurance-type activity using rhythmic
movements of large muscle groups are the
best studied
Prevention of OA
• Exercise reduces the pain and functional
disturbance in OA of the knee (SOR A)
– Data insufficient for conclusions about the type
of exercise that should be preferred
• Sudden overloading, incorrect joint loading,
and various injuries predispose people to
OA
• Preventing excessive wt gain helps
Prevention of OA
• Current studies
– Isokinetic exercise for improving knee flexor
and extensor muscles in healthy adults to assess
safety and effectiveness
– Will also assess in adults with neurological,
orthopedic, and rheumatologic conditions
Management/Treatment of OA
• Goals
–
–
–
–
Educate patient about disease and management
Improve function
Control pain
Alter disease process and its consequences
Management/Treatment of OA
• No known cure for OA
• HOWEVER
– Impaired muscle function
– Reduced fitness
• Affect pain and dysfunction
• Are amenable to therapeutic exercise
Management/Treatment of OA
• Pharmacologic
– Acetaminophen
– NSAIDS
• Cox-2 specific
inhibitors
• With PPI or misoprostol
– Nonacetylated
salicylate
– Tramadol
– Opioids
• Topical
– Capsaicin
– Methylsalicylate
– NSAIDS
• Intra-articular
– Corticosteroids
– Hyaluronic acid
Treatment/Management of OA
• Pharmacologic
– Acetaminophen
• Grade A/Level I for short-term pain relief
• Pain decreased 4 points (100 point scale) compared
to placebo
• Relatively inexpensive compared to NSAIDS
• Relatively safe compared to NSAIDS
• Usually studied in doses of 2-4 g/d
• Liver toxicity is major concern
Management/Treatment of OA
• Pharmacologic
– NSAIDS
• Grade A/Level I for short-term pain relief
• Shown to provide better pain control than
acetaminophen, especially with more severe pain
• No difference in functional improvement
• Greater GI toxicity than acetaminophen
• No difference in efficacy among NSAIDS
Management/Treatment of OA
• Pharmacologic
– Tramadol
• Pain decreased 8.5 points compared to placebo
• 39 had minor side effects (18 with placebo)
• 21 had major side effects (8 with placebo)
– Opioids
• Grade B/ Level I for pain control in OA
• Must balance side effect profile for risk/benefit
Management/Treatment of OA
• Pharmacologic
– Topical Capsaicin
• Inconclusive evidence
– Topical NSAIDs
• + short-term pain relief in very limited short-term
studies only compared to placebo.
• No studies comparing to PO medications
Management/Treatment of OA
• Pharmacologic
– Intra-articular steroids
• Grade A/Level I for short-term pain relief
– Intra-articular hyaluronic acid
• Grade A/Level I for short-term treatment
Treatment/Management of OA
• Pharmacologic
– Intraarticular corticosteroids
• Superior to placebo for pain control for 2-3 weeks
• At 4-24 weeks, no evidence of improvement in pain
• No evidence of improvement in function
– Hyaluronic acid
• More effective than corticosteroids 5-13 weeks postinjection (pain, ROM, function)
Treatment/Management of OA
• Pharmacologic
– Hyaluronic acid (HA)
• Better than placebo
• Comparable effectiveness to NSAIDs
– Fewer systemic adverse events
– More local reactions
• Longer-acting than IA steroids
• No major safety issues
• SOR B (76 heterogeneous trials)
Treatment/Management of OA
• Pharmacologic
– Herbal therapy
• Avocado soybean unsaponifiables (ASU’s) with
promising results in 2 studies on:
– Functional index, pain, NSAID use, and global evaluation
• Reumalex (willow bark preparation) inconclusive
• Tipi tea inconclusive
Management/Treatment of OA
• Possible structure/disease modifying stuff
–
–
–
–
–
–
Glucosamine
Diacerein
Cytokine inhibitors
Cartilage repair
Bisphosphonates
Degradative enzyme inhibitors
• Tetracyclines, metalloproteinase inhibitors
Treatment/Management of OA
• Pharmacologic
– Glucosamine 20 studies with >2500 patients
• If only high quality studies evaluated:
– No benefit over placebo on pain
• If all studies included:
– Pain may improve by as much as 13 points
• 2 RCT’s using Rotta preparation:
– Demonstrated slowing of radiological progression of OA
over a 3 year period
Treatment/Management of OA
• Pharmacologic
– Diacerein
• Pain improved 5 points compared to placebo
• Over 3 years,
– Slowed progress of OA in the hip compared to placebo
– Did not slow progress of OA in the knee
• Diarrhea is most common side effect
– 42 out of 100 had diarrhea in the first 2 weeks
– 18 discontinued because of side effects (13 in placebo)
Management/Treatment of OA
• Non-pharmacologic
– Patient education
– Self-management
programs
– Weight loss
– PT/OT
– ROM exercises
– Muscle strengthening
• Non-pharmacologic
–
–
–
–
–
–
Assistive devices
Patellar taping
Appropriate footwear
Lateral-wedged insoles
Bracing
Joint protection and
energy conservation
Management/Treatment of OA
• Non-pharmacologic (Exercise)
– Walking program v. control. Level I/Grade A (RCT
n=1089) for improvement in:
•
•
•
•
•
•
•
Pain
Functional status
Stride length
Aerobic capacity
Energy level
Medication use
Disability transferring from bed and bathing
Management/Treatment of OA
• Non-pharmacologic (Exercise)
– Whole-body functional exercise v. control.
Level I/Grade A (RCT n=864) for:
•
•
•
•
•
•
Pain
Functional status
Mobility
Walking
Work
Disability in Activities of Daily Living (ADL’s)
Management/Treatment of OA
• Non-pharmacologic (Exercise)
– Home strengthening program for knee v. control. Level
I/Grade A (controlled clinical trial n=81) for:
•
•
•
•
Pain
Functional status
Energy level
Range of motion (ROM) in flexion
• Other studies: group exercise program as
effective as one-on-one
Management/Treatment of OA
• No differences between high and low intensity
aerobic exercise in people with OA for:
–
–
–
–
Functional status
Pain
Gait
Aerobic capacity
• Therapeutic range (btwn suitable and excessive
exercise) may be narrow in some patients
Management/Treatment of OA
• Non-pharmacologic (brace) study (SOR B)
–
–
–
–
Valgus knee brace better than:
Neoprene sleeve better than:
Control group according to pain scale
While score changes were statistically
significant, clinical significance is questionable
– Study only lasted 6 months. <500 patients
Management/Treatment of OA
• Non-pharmacologic (insole) study (SOR B)
– Laterally wedged insoles may decrease knee OA pain
– Laterally wedged insoles decrease the amount of pain
medication taken
– Pain decreased by one point (100 point scale) in
laterally wedged insoles. Decreased by 5 points in
neutrally wedged insoles. However, pain medication
use decreased more in laterally wedged insole patients
and patients wore the laterally wedged insoles for a
longer period of time
Management/Treatment of OA
• Non-pharmacologic (exercise programs)
– Exercise programs improve health and function
(SOR A)
– People tend to stick with a home exercise
program more than exercising at a center (SOR
B)
– The specific type of exercise that is best needs
more research
Management/Treatment of OA
• Thermotherapy
– Heat had no benefit on swelling over cold or
placebo
– Cold did not significantly improve pain
– Cold did slightly improve swelling
– Ice 20 min/d 5d/wk for 2 weeks did show
improved muscle strength, ROM, and a
decrease in time to walk 50 feet
Management/Treatment of OA
• Ultrasound was of no benefit for:
– Pain
– Range of motion
– Functional status
Treatment/Management of OA
• Transcutaneous electrical nerve stimulation
(TENS) for knee OA
– Active and “acupuncture like” TENS for at
least four weeks reduced pain and knee
stiffness (SOR B)
• Electrical stimulation
– Showed improvement in measurements, but
– Clinical significance from the patient’s
perspective is questionable
Treatment/Management of OA
• Surgery
– Valgus high tibial osteotomy (HTO) for
treatment of medial compartment OA
• No study comparing HTO to conservative txment
– Partial knee replacement
– Total knee replacement
• Pre-op education only reduced hospital stay
in patients with complex needs
Treatment/Management of OA
• Current studies
– Non-pharmacologic
• Aquatic exercise for the treatment of knee/hip OA
• Acupuncture for osteoarthritis
– Pharmacologic
• Chloroquines, HRT, chondroitin, homeopathy
• Opioids
Summary
• Non-pharmacologic therapy is important in the
prevention and treatment of OA
• The best studied and most effective nonpharmacologic therapy is EXERCISE
• Exercise helps control weight, increase strength,
improve and maintain function and decrease pain
• Traditional belief - patients concerned that joint
use will “wear out” a damaged joint that is already
“worn out” - NOT true for moderate intensity
exercises
OA – Arthroscopic Treatment
•In addition to being the most accurate way of determining how
advanced the osteoarthritis is:
•Arthroscopy also allows the surgeon to debride the knee joint
•Debridement essentially consists of cleaning out the joint of all debris and
loose fragments. During the debridment any loose fragments of cartilage
are removed and the knee is washed with a saline solution.
•The areas of the knee joint which are badly worn may be roughened with
a burr to promote the growth of new cartilage - a fibrocartilage material
that is similar scar tissue.
•Debridement of the knee using the arthroscope is not 100% successful. If
successful, it usually affords temporary relief of symptoms for somewhere
between 6 months - 2 years.
•Arthroscopy also allows access for surgical treatment of articular
cartilage: graft-transplantation, micro-fracture techniques, subchondral drilling
OA – Disease Management
•OA is a condition which progresses slowly over a
period of many years and cannot be cured
•Treatment is directed at decreasing the symptoms of
the condition, and slowing the progress of the
condition
•Functional treatment goals:
•Limit pain
•Increase range of motion
•Increase muscle strength
OA – Non-operative Treatments
•Pain medications
•Physical therapy
•Walking aids
•Shock absorption
•Re-alignment through
orthotics
•Limit strain to affected
areas
Proximal Tibial Osteotomy
•Osteoarthritis usually
affects the inside half
(medial compartment) of
the knee more often than
the outside (lateral
compartment).
•This can lead to the lower
extremity becoming
slightly bowlegged, or in
medical terms, a genu
varum deformity
Proximal Tibial Osteotomy
•The result is that the weight bearing line of the lower
extremity moves more medially (towards the medial
compartment of the knee).
•The end result is that there is more pressure on the medial
joint surfaces, which leads to more pain and faster
degeneration.
•In some cases, re-aligning the angles in the lower extremity
can result in shifting the weight-bearing line to the lateral
compartment of the knee. This, presumably, places the
majority of the weight-bearing force into a healthier
compartment. The result is to reduce the pain and delay the
progression of the degeneration of the medial compartment.
Proximal Tibial Osteotomy
•In the procedure to realign the
angles, a wedge of bone is
removed from the lateral side
of the upper tibia.
•A staple or plate and screws
are used to hold the bone in
place until it heals.
•This converts the extremity
from being bow-legged to
knock-kneed.
•The Proximal Tibial Osteotomy buys some time before ultimately
needing to perform a total knee replacement. The operation
probably lasts for 5-7 years if successful.
Total Knee Replacement
The ultimate solution for osteoarthritis of the knee is to
replace the joint surfaces with an artificial knee joint:
•Usually only considered in people over the age of 60
•Artificial knee joints last about 12 years in an elderly population
•Not recommended in younger patients because:
•The younger the patient, the more likely the artificial joint will fail
•Replacing the knee the second and third time is much harder and much less
likely to succeed.
•Younger patients are more active and place more stress on the artificial
joint, that can lead to loosening and failure earlier
•Younger patients are also more likely to outlive their artificial joint, and
will almost surely require a revision at some point down the road.
•Younger patients sometimes require the surgery (simply because
no other acceptable solution is available to treat their condition)
Total Knee Replacement
•The ends of the femur, tibia, and patella are shaped to accept
the artificial surfaces.
•The end result is that all moving surfaces of the knee are
metal against plastic
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Total Knee Replacement
Photographs of total knee
components on model
bone
Total Knee Replacement
Unicompartmental Knee Replacement
•When only one part of the knee joint is arthritic, it may be
possible to replace just this part of the joint
•The procedure is similar to a total knee replacement, but only
one side of the joint is resurfaced
•A metal component is fit onto the femur and a plastic bearing
is inserted either directly onto the tibia or onto a metal tray
which has been fit onto the tibia
•Recovery time is generally slightly shorter following this
kind of surgery.
THOUGHT FOR THE DAY
• A SHORT HISTORY OF MEDICINE: "Doctor, I
have an ache."
2000 B.C. - "Here, eat this root."
1000 B.C. - "That root is heathen, say this
prayer."
1850 A.D. - "That prayer is superstition, drink
this potion."
1940 A.D. - "That potion is snake oil, swallow
this pill."
1985 A.D. - "That pill is ineffective, take this
antibiotic."
2000 A.D. - "That antibiotic is artificial. Here, eat this root.
Questions?
…The End