Inflammatory Arthritides Flashcards
AS, RA, & OA
Describe a ‘swan neck deformity’
hyperextension at the PIP joint, flexion at the DIP joint
Describe a ‘boutonniere deformity’
flexion at PIP, hyperextension at DIP joint
What causes a swan neck deformity?
intrinsic hand muscle contracture (laxity of PIP joint w/ overstretched palmar plate & bow stringing of lat. band of extensor hood = hyperextension of PIP, flexion of DIP)
What causes a boutonniere deformity?
rupture of the central band of extensor hood (lat band of extensor hood = slip of PIP = flexion of PIP and extension of DIP).
What is an ‘ulnar drift deformity’?
ulnar deviation of the hand with subluxed MCP joints
What is a Baker’s cyst?
enlargement of the posterior knee bursa (may occur in RA impacted knee joints)
The inflammatory stage of AS usually ends by age…
40
AS synovitis usually begins at what joints, and then progresses…
SI joints, up the spine
90% of people diagnosed with AS have what in common?
HLA-B27 gene
Severe, longstanding AS can also see inflammation of the iris, which is called…
uveitis (present in up to 30% with AS)
How does AS change breathing?
it becomes primarily diaphragmatic as chest expansion is reduced
What is seen in 90% of RA cases after the first year?
the joints initially involved are the joints ultimately affected
True or false: in RA, joints are usually affected asymmetrically.
false. usually symmetrical
What is the role of proteolytic enzymes in RA?
attack and erode cartilage, eventually exposing subchondral bone
In severe cases of RA, erosion of what features in the neck can lead to cervical instability?
the alar ligament, transverse ligament, odontoid process
What is seen in RA - genu varus or valgus?
valgus
What commonly happens to the MCP joints in RA?
ulnar drift (deviation) and palmar subluxation
The deformity of the thumb commonly seen in RA is called…
zig zag deformity (mm imbalances and lig. laxity lead to MCP dislocations)
*thumb becomes flexed and adducted
What is a proteoglycan?
proteins that bind water and make up a major part of the ECM of cartilage (give cartilage its elasticity)
Why is cartilage so resilient?
its high water content (up to 80% of the ground substance)
The initial response of cartilage to damage is to self repair by…
increasing water content and number of proteoglycans (load bearing portions of articular cartilage are affected first w. OA)
In later stages of osteoarthritis, what happens to the subchondral bone?
it remodels & thickens (the exposed surface becomes eburnated = bone turns into hard, ivory-like mass)
What happens to the joint capsule and synovium in the later stages of OA?
they thicken in response to chronic irritation
Describe the progression of a patient’s experience of pain as OA progresses.
no pain until bone on bone
pain will then follow moderate joint use
progresses to pain with minimal active motion, passive motion, and eventually even at rest
Where are Bouchard’s nodes found?
PIP joint (enlarge)
Where are Heberden’s nodes found?
DIP joints
Osteophyte formation in the spine can lead to…
narrowing of the intervertebral foramen
spinal stenosis
…leading to compression of nerve roots, intermittent radicular pain
With hip OA, which two osteokinematic movements see a reduction in range?
IR, ext. (pain over the groin and adductors)
What are some CI’s for all inflammatory arthritides?
no provocative testing (except aROM)
no hot hydro on areas of inflammation
no tx if fever
no circulatory techniq. distal to areas with swelling
no lymph drainage
do not mobilize unstable or ankylosed joints
How does AS affect posture?
loss of lumbar curvature (lordosis)
flexion contractures in the hips
thoracic curvature becomes more apparent
chest becomes fixed/flattened
When should cold hydro to affected joints be used with RA?
during flareups
With AS, chest expansion is reduced as a result of what joints being impacted…
costovertebral joint
RA begins with activation or injury of…
synovial microvasculature of the endothelia cells
What % of those with RA has an unremitting and progressive course of development?
3%
These 7 joints are the most commonly involved in RA…
PIP MCP Wrist Knees MTP subtalar C1/C2
As RA progresses, synovitis occurs and the synovial membrane…
thickens and folds (similar to granulation which occurs with wound healing)
define pannus:
vascularized membrane that extends from the synovium to involve the articular cartilage (pannus develops between the joint margins, forming adhesions which restrict ROM)
Where do rheumatoid nodules develop?
where skin and subcutaneous tissue are subject to pressure (ex. extensor surface of forearm)
Synovial joints are composed of…
hyaline cartilage-covered bone ends connected by a fibrous joint capsule and reinforced extra-capsular ligaments
Hyaline cartilage is a low friction, wear resistant tissue present within joints that is designed to…
bare and distribute weight (strong, rubbery, flexible - like nose and ears)
With OA, as collagen fibers continue to break, what happens?
proteoglycans are depleted and cartilage softens and becomes thinner.
How do vertical clefts result in pain for people with OA?
they develop in the articular cartilage surface and deepen, allowing for cartilage to fragment off into the synovial fluid, eventually extending to subchondral bone underneath.
subchondral bone is pain sensitive.
