Arthropathies Flashcards
Bone physiology : Synovial joint.
What is it
A synovial joint is where two bones meet
* Each surfaced by hyaline articular
cartilage ) inability to repair itself)
* The interior lining of the joint is made up of
a synovium
* This produces synovial fluid
Types of arthritis
osteoarthritis
Inflammatory disease of joints with unknown aetiology : RhA
Seronegative arthropathies: Ankylosing spondylitis
Psoriatic arthritis
Inflammatory disease of the joint of KNOWN aetiology
Gout
Specific bacterial infection in the joint
Acute and chronic infections
Osteoarthritis (OA)
A clinical syndrome characterised by progressive loss of articular cartilage, remodelling and sclerosis of subchondral bone & formation of marginal osteophytes
How is OA characterised as
-Can be primary idiopathic generalised OA
or
Secondary OA
Imbalance of damage and repair -
-Degeneration of the articular cartilage
-Osteophytes
-Changes in the synovial membrane
-Can affect all joints, but usually large-weight
bearing joints
OA-Pathogensis
Disease process affecting the cartilage.
Normal cartilage is composed of a matrix of collagen fibres with proteoglycan molecules that maintain a positive pressure within the joint.
Adverse trauma – increases chondrocyte activity.
Chondrocytes release hydrolysing enzymes that degrade collagen and allow uptake of water.
Cartilage swells and degrades leading to progressive cartilage degeneration and subchondral bone thickening.
Resultant joint space narrowing and osteophyte formation
Diagnosis of OA
Clinical or radiological
xrays -Looking for:
-Subchondral sclerosis
-Narrowing of Joint Space between articulating bones
-Osteophyte formation
Clinical features
Associated muscle atrophy with chronic OA
Pain worsening with prolonged exrecise
<30 mins joint stiffness
Usually assymetrical
Crepitus on movement
Pain/tenderness/movement restriction
Joint margin pain
Factors outside of Joint that contribute to the disease?
Muscle strength
Ligamentous stability
Pain apprehension leading to chronic pain behaviour
What happens to articular cartlage in OA
Degenerates
What causes OA
Idiopathic OA -Unknown , genetics
Secondary OA - Age Weight, nutrition, injury
What typical changes would you usually see on an xray of osteoarthtritic joint
Sclerosis, osteophytes , joint narrowing
Name some clinical features of OA , what might patient complain of
Light Exercise improves symptoms, pain
progressive with prolonged exercise, Crepitus on
movement, Restriction of movement
Rheumatoid arthritis RhA
Chronic autoimmune inflammatory polyarthropathy characterised by progressive destruction of synovial joints and as having extra-articular features
Flares can be triggered by smokng, stress or other causes. of chronic inflammation.
Extra articular features
Subcutaneous nodules
-Lung fibrosis/pleural effusions
-Vasculitis
-PAD
-Neuropathy - Peripheral nerve entrapment, carpal and tarsal tunnel syndrome
-Bone marrow changes
N.B. Occurs only in patients +ve for Rheumatoid factor
‘Extra-articular manifestations of RhA occur in about
40% of patients, either in the beginning or during the
course of their disease’
(Cojocaru et al., 2010)
Pathogenesis of RhA
Elevated levels of TNF alpha stimulate the liver to release C-reactive protein, increasing the systemic inflammatory process
The first joint tissue to be affected is the synovial membrane within the joint
Infiltration of inflammatory factors leads to synovitis.
Further influx and escalating inflammatory cascades lead to abnormal synovium thickening, bone destruction and loss of cartilage Joint destruction follows due to Pannus formation, joint effusion and inflammation of synovium, which produces joint swelling
