Osteoarthritis is the most common form of joint disease. It is a non-inflammatory disorder affecting synovial joints that results from cartilage damage within the joints. Over time, the damaged cartilage leads to thinning of cartilage and bone growths around the joint margins. This causes pain, stiffness, and deformity of the joints. The most commonly affected joints are those in the hands, hips, knees, and lower back. Symptoms include joint pain that worsens with use and is relieved by rest, crepitus, and morning stiffness.

1. Osteoarthritis

2. Objectives
 Compare & contrast the sequence of
events leading to joint destruction in
osteo-arthritis & rheumatoid arthritis
 Describe the clinical manifestations of
OA and RA

3. Osteoarthritis
 Most common form of joint disease in
NZ
 Non-inflammatory disorder of the
synovial joints
 Slowly progressive
 More than 90% of adults are affected
by age 40

4. Osteoarthritis
 Before age 50, men are more often
affected than women
 Incidence of OA after 50 is twice as
great in women

5. Etiology and Pathophysiology
Cause can be unknown or a known
event or condition that directly
damages cartilage or causes joint
instability e.g.. trauma, repetitive
physical activities, congenital
dislocation of the hip

6. Etiology and Pathophysiology
 Estrogen reduction at menopause
 Genetic factors
 Obesity
 Strenuous exercise activities

7. Etiology and Pathophysiology
 Results from cartilage damage
 Causes the normally smooth, white,
translucent articular cartilage to
become dull, yellow & granular
 Affected cartilage:
– Dull, yellow, granular
– Softer, less elastic
– Less able to resist wear

8. Etiology and Pathophysiology
 Body’s attempts at repair cannot keep
up with destruction
 Continued changes in collagen
structure  fissuring and erosion

9. Etiology and Pathophysiology
 Central cartilage becomes thinner
 Cartilage and bony growth
(osteophytes) increase at the joint
margins
 Secondary synovitis
– Inflammatory changes  early pain
and stiffness

11. Pathophysiology of osteoarthritis

12. Clinical Manifestations
 No systemic manifestations
 Joint pain
– Predominant symptom
– Relieved by rest in early stages

13. Clinical Manifestations
 Joint pain
– Generally worsens with joint use
– May become worse as barometric
pressures fall before inclement
weather

14. Clinical Manifestations
 Joint pain
– May be referred to:
• Groin
• Buttock
• Medial side of thigh or knee

15. Clinical Manifestations
 Joint pain
– Crepitation
• Grating sensation caused by loose
particles of cartilage in the joint
cavity

16. Clinical Manifestations
 Joint pain
– Affects joints asymmetrically
– Early morning stiffness
• Resolves within 30 minutes

17. Clinical Manifestations
 Most commonly involved joints:
– Distal interphalangeal (DIP)
– Proximal interphalangeal (PIP)
– Carpometacarpal joint of the thumb
– Weight-bearing joints (hips, knees)
– Metatarsophalangeal (MTP)
– Cervical and lower lumbar vertebrae

18. Joints Involved in Osteoarthritis
Fig. 63-2

19. Clinical Manifestations -
Deformity
 Specific to involved joint
– Heberden’s & Bouchard’s nodes
• Indication of osteophyte formation &
loss of joint space
• Appear from age 40 & tend to be seen
in families
• Often red, swollen & tender
• Do not cause significant loss of
function

20. Hand Deformormities - Nodes

21. Osteoarthritis Hands

22. Clinical Manifestations
 Deformity
– Bouchard’s nodes
• PIP joints
– Nodes often red, swollen, tender