1. and
present
Course of osteoarthritisCourse of osteoarthritis

2. How to define osteoarthritis
 There are several "levels" of osteoarthritis:
anatomical, radiological and symptomatic
 Many people have radiologically
evident but asymptomatic
osteoarthritis
 Osteoarthritis is not necessarily
synonymous with "pain"
 Thus, of 100 people aged over 65:
2
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
INSERM (National medical research institute) web site:
http://www.inserm.fr/thematiques/circulation-metabolisme-nutrition/dossiers-d-information/arthrose

3. Chronic degenerative joint disease
 Osteoarthritis is characterised by:
 gradual destruction of the cartilage (chondrolysis)
 remodelling of the subchondral bone
 marginal osteophytosis
 and secondary synovial inflammation
3
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686
External facet stage 4 chondral lesion. Axial
image from a knee CT arthrography.

4. 4
External facet stage 4 chondral lesion. Axial
image from a knee CT arthrography.

5. What type of osteoarthritis?
A distinction is made between:
 Symptomatic osteoarthritis which causes pain and functional disability
and is visible on radiographic images
 Weight-bearing joint osteoarthritis (hip and knee)
 Non-weight-bearing joint osteoarthritis
(hand and shoulder)
 Primary osteoarthritis
 Secondary osteoarthritis arising subsequent
to other conditions (injury, malformation
or metabolic and inflammatory disorders)
5
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686

6. 6
Hip osteoarthritis
surrounding the hip.
Internal and external femorotibial
osteoarthritis. Knee CT-arthrography.
Rapidly destructive osteoarthritis of the shoulder, frontal
image gadolinium-enhanced T1 MRI sequence
Hand and wrist
MRI: SE T1-
weighted,
gadolinium-
enhanced coronal
image with fat
suppression.

7. Oedema and fissures
Cartilage lesions start with oedema which divides the collagen fibres
 Superficial fissures appear
 Chondrocytes try to compensate for the breakdown of the proteins
making up the matrix by producing growth factors
 The fissures then extend down to the subchondral bone, leaving it
exposed,
 The number of chondrocytes drops and their pro-destructive potential
increases
 The subchondral bone becomes osteosclerotic at the pressure points
resulting in the development of cysts
 Osteophytes (attempted bone repair), also known as bony spurs,
develop in marginal areas which are not under pressure
7
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686

8. The role of the chondrocyte
 Osteoarthritis is not caused by cartilage wear and tear
only
 Chondrocytes "wake-up" and start to synthesise:
 pro-inflammatory cytokines (IL-1, TNF)
 nitrogen monoxide (NO)
 pro-inflammatory lipid mediators (PGE2)
 and proteolytic enzymes (metalloproteases or MPPs and
aggrecanases) which cause cartilage matrix breakdown
8
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686

9. Imbalance between destruction
and synthesis
During stress, for example when subjected to
excessive mechanical load, the chondrocyte
metabolism changes
 The cell becomes capable of boosting synthesis of
matrix components and proteolytic enzymes
 and reduces release of anti-inflammatory mediators
or metalloprotease inhibitors produced to halt the
inflammatory process and prevent cartilage
destruction (TIMP: tissue inhibitor of
metalloproteinases, an IL-1 receptor antagonist)
 This imbalance leads to digestion and destruction of
the cartilage matrix, which is then not renewed at the
same pace as new components are made
9
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686

10. 10
According to Maheu 2012

11. Fine balance between formation
and degradation
Synoviocytes in the inflammatory synovial membrane
and osteoblasts in the subchondral bone are also capable
of secreting mediators, thus contributing to destruction
of the cartilage
 Thus, the balance between synthesis and breakdown
of the cartilage matrix is upset in favour of cartilage
degradation
 Once fragments of the matrix are released into the
synovial fluid, the inflammation continues as a result
of chronic activation of chondrocytes and the synovial
membrane
 Resulting in increased synthesis of pro-inflammatory
mediators
11
Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686
According to Piperno 2012

12. In sum,
12
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686
Imbalance between synthesis and destruction of the cartilage matrix
explaining extracellular matrix loss
D’après Sellam 2011

13. Pain is a measure of increasing damage
 During these flares, the
osteoarthritis is active and
inflammatory phenomena occur
 This is caused by a synovial
membrane reaction: the synovial
membrane's job is to cleanse the
joint of the debris created by
cartilage breakdown
13
Knee osteoarthritis, tibial edema and synovial
inflammation. FSE T2 sagittal slices.Société Française de rhumatologie website:
http://www.rhumatologie.asso.fr/04-Rhumatismes/grandes-maladies/0B-dossier-arthrose/A0_definition.asp

14. Inflammatory flares
 Recent change in pain intensity:
 sudden increase in intensity over a few days
 pain at night which wakes the patient up
 morning stiffness lasting more than 15
minutes
 +/-mechanical pain as soon as any
pressure is placed on the joint.
14
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686
 Onset of joint effusion
 Presence of signs of local inflammation: redness

15. 15
According to Sellam 2011

16. Does osteoarthritis always progress
in flares?
The natural history of osteoarthritis
has not yet been fully elucidated
It varies widely depending on the joint
affected and the patient
Once diagnosed, it seems to progress
in a non linear fashion
Two other patterns of progression have also
been described:
 rapidly destructive osteoarthritis, which
causes complete destruction of the cartilage
within 24 months
 and slowly progressing osteoarthritis,
without obvious flares
16
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686

17. Evaluation tools
Different tools can be used:
 Visual analogue scales for pain,
functional impairment and, in the case
of hand osteoarthritis, aesthetic impact
 For leg osteoarthritis, maximum
walking distance with and without pain
and ability to complete daily tasks
 Quantification of analgesic and NSAID
consumption
 Several indices are used for hip or knee
osteoarthritis:
• the Lequesne index
• the WOMAC (Western Ontario and McMaster
Universities composite index)
17 Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686

18. 18
According to Sellam 2012

19. Three progressive disease profiles
 Slow progress without any obvious
 Progress in flares alternating with stable periods
and periods of chrondrolysis: most common
 Rapid progress: rapidly destructive osteoarthritis
(total cartilage destruction in 6 to 24 months)
19
Sellam J, Berenbaum F. Arthrose. Rev Prat. 2011; 61: 675-686
In all cases, an inflammatory flare is believed to
be an indication of accelerated cartilage destruction
Which is why it is so important to treat each painful flare