2. DEFINITION
Osteoarthritis is a non-inflammatory,
degenerative condition of joints
Characterized by degeneration of articular
cartilage and formation of new bone i.e.
osteophytes.
3. Common in weight-bearing joints such as hip and knee.
Also seen in cervical , lumbosacral spine and in hands (DIP, PIP, base of thumb).
Both male and females are affected.
But more common in older women i.e. above 50 yrs,particularly in postmenopausal
age.
4. JOINT PROTECTIVE MECHANISMS
SYNOVIAL FLUID
JOINT CAPSULE AND LIGAMENTS
MUSCLE
SENSORY AFFERENTS
UNDERLYING BONE
5. SYNOVIAL FLUID
Reduces friction between articulating cartilage surfaces
Hyaluronic acid + lubricin
Concentration of the above – reduced in injury/ inflammation of synovium
6. LIGAMENTS, SKIN, TENDONS
Contain mechanoceptor sensory afferent nerves
Provide feedback via spinal cord to muscles + tendons
7. CARTILAGE
Impact absorbing capacity along with synovium
Earliest OA changes occur here
Healthy cartilage – avascular due to angiogenesis inhibitors in cartilage
Diseased cartilage – invasion of blood vessels into cartilage from bone and proliferation
in synovium
VEGF synthesis in bone + cartilage is implicated
OA cartilage – depletion of aggrecan, loss of type 2 collagen, unfurling of collagen
matrix
8.
9. PATHOLOGY
OA is a degenerative condition primarily affecting the articular cartilage.
1.articular cartilage
2.Bone
3.Synovial membrane
4.capsule
5.Ligament
6.muscle
10. Articular Cartilage
o Cartilage - 1st structure to be affected.
o Erosion occurs, often central & frequently in wt. bearing areas.
o Fibrillation - causes softening, splitting and fragmentation of cartilage,in both wt.
bearing & non-wt. bearing areas.
o Collagen fibres split , disorganisation of proteoglycan-collagen relationship
o Further softening and flaking.
o Flakes of cartilage break off, may be impacted b/w jt.surfaces locking and
inflammation.
11. Right: Early OA with
area of cartilage loss in
the center.
Left: More advanced
changes with extensive
cartilage loss and
exposed underlying
bone
13. Bone(Eburnation)
Bone surface become hard & polished as there is loss of protection from the cartilage.
Cystic cavities form in the subchondral bone because eburnated bone is brittle and
microfractures occur.
Venous congestion in the subchondral bone.
14. Gross superior view of a
femoral head from a
patient with radiographic
stage I OA. This shows an
area of complete cartilage
loss, with polishing or
eburnation of the
underlying bone.
15. Osteophytes form at the margin of the articular surface,which may get projected into
the jt. Or into capsule & ligament,bone of the wt.-bearing jt.
There is alteration in the shape of the femoral head which becomes flat and
mushroom shaped.
Tibial condyles become flatened.
17. Synovial Membrane
o Synovial membrane undergo hypertrophy and become oedematous (which can
lead to ‘cold’ effusions).
o Reduction of synovial fluid secretion results in loss of nutrition and lubricating action of
articular cartilage.
o Capsule
o It undergoes fibrous degeneration and there are low-grade chronic inflammatory
changes
18.
19. Ligament
Undergoes fibrous degeneration
There is low grade chronic inflammatory changes and acc.to the aspect joint become contracted
or elongated.
Muscles
Undergoes atrophy, as pt. is not able to use the jt. Because of pain which further limits movts. and
function.
20.
21.
22. CLINICAL FEATURES
JOINT PAIN – ACTIVITY RELATED
IN EARLY DISEASE – Episodic, triggered by overuse of diseased joint
Progressively, continuous pain, even disturbs sleep at night
Stiffness of the joint.
Morning stiffness – brief ( <30min)
In knee- buckling, catching, locking
Pain with activities requiring knee flexion ( climbing stairs, rising from a chair )
23.
24. Osteoarthritis of the DIP
joints. This patient has
the typical clinical
findings of advanced
OA of the DIP joints,
including large firm
swellings (Heberden’s
nodes), some of which
are tender and red due
to associated
inflammation of the
periarticular tissues as
well as the joint.
26. A patient with
typical OA of the
knees. In the normal
standing posture
there is a mild varus
angulation of the
knee joints due to
symmetrical OA of
the medial
tibiofemoral
compartments.
27. Radiographic Classification
Stage 1
Stage 2
Stage 3
Stage 4
Bony spur only
Narrowing of jt.
Space,less than half of
the normal jt. space
Narrowing of jt.
Space,more than half
of the normal jt. space
Obliteration of jt. space
Stage 5 Subluxation or
sec.lateral arthrosis
28.
29. Special Investigations
• Blood tests: Normal
• Radiological features:
– Cartilage loss
– Subchondral sclerosis
– Cysts
– Osteophytes
30.
31. Treatment Principles
• Education
• Physiotherapy
– Exercise program
– Pain relief modalities
• Aids and appliances
• Medical Treatment
• Surgical Treatment
32.
33. Aids and appliances
• Braces / splints
• Special shoes/insoles
• Mobility aids
• Aids: dressing, reaching, tap openers,
kitchen aids
• Taping of patella in patello femoral OA
34. Use of a cane, stick or other walking aid. This patient,
who has hip OA, has found that she can reduce the
pain in her damaged left hip by leaning on the stick in
the right hand as she walks. The reduction in loading
can be huge, and the effect on symptoms and
confidence with walking very beneficial.
35.
36.
37. Joint replacement surgery
• Indications: pain affecting work, sleep,
walking and leisure activities
• Complications
– sepsis
– loosening
– lifespan of materials (mechanical failure)