Secondary osteoarthritis can occur at any age in a previously damaged or congenitally abnormal joint. It is caused by "wear and tear" and most commonly affects the vertebrae, hips, and knees. There are two main theories for the cause of osteoarthritis - the biomechanical theory, which states that wear and tear leads to cartilage breakdown and bone changes, and the biochemical theory, which maintains that aging causes reduced cartilage maintenance and an excess of enzymes that degrade the cartilage. The primary symptom of osteoarthritis is thinning and fragmentation of the articular cartilage, which leads to joint stiffness, pain, and disability.

6. SECONDARY OA: Appears at any age in a
previously damaged or congenitally abnormal
joint . OA is a “wear and tear” phenomenon.
Indeed the vertebrae , hips and knees are most
affected . OA can be superimposed upon
RHEUMATOID ARTHRITIS.

7. Two main theories:
1)BIOMECHANICAL THEORY
2)BIOCHEMICAL THEORY

8.  This maintains the wear and tear leads
to deranged function,focal death, and
reactive proliferation of chondrocytes.
 Collagen breakdown , fissuring and
flaking and osteophyte formation
occurs.

9. maintains that aging leads to lessened
matrix maintenance and excess of
lytic enzymes , which in turns lead to
synovitis . Synovitis further results in
a release of inflammatory mediators
and cytokines(especially IL-1) ,
degradative enzymes and free
radicals and eventually chondrocyte
death.

10.  Primary abnormality is thinning and
fragmentation of the articular
cartilage.
 Loss of articular cartilage leads to exposure of
subchondral bone , which appears as shiny
foci on the articular surface( enburnation ).
 New bone formation , usually in the form of
nodules (spurs).
 Formation of osteocartilagenous loose bodies
(“joint mice”).
 Inflammation is absent.

11. CLINICAL FEATURES:
Although OA may be asymptomatic,most
patients experience morning stiffness in
affected joints . There is usually no local
heat or tenderness , but affected joints
often show restricted range of motion ,
small efusions and crepitus. A slowly
progressive disease characterized by joint
disability.It is associated with
ALKAPTONUREA and FOOTBALL
PLAYERS.

12. OSTEOARTHRITIS IN KNEE JOINT.

13. OSTEOARTHRITIS.