Introduction to Joints of the Lower Limbs and Clinical Relevence

Question 1

What is the most common joint type

Answer 1

Synovial Joints

Question 2

Describe the articular surfaces of synovial joints

Answer 2

Free

Question 3

Describe a synovial joint

Answer 3

Bones/Cartilage are joined in a fibrous joint capsule that is continuous with the periosteum of the joined bones

Question 4

Name the epithelial cells which surround the joint cavity

Answer 4

Synovium

Question 5

Describe the nature and role of synovium cells

Answer 5

Simple squamous epithelial cells that produce joint fluid

Question 6

Fibrous Capsule

Answer 6

Layer which surrounds the articular capsule of a synovial joint

**Lined with synovium

Question 7

Additional supporting structures that keep synovial joints together

Answer 7

Ligaments, Tendons, Muscles

Question 8

Main types of Synovial Joint Disease

Answer 8

Bursitis
Osteoarthritis
Rheumatoid Arthritis
Gout

Question 9

Bursa and their lining/role

Answer 9

Fluid filled sac which provides free movement between bones and tendons or muscles around a joint

Lined by synovial cells, secreting synovial fluid

Question 10

Bursitis - Causes, Symptoms & Common areas

Answer 10

Inflammation of the Bursae

From repetitive use, trauma or arthritis

Pain when inflamed as they become swollen, causing pressure & reducing friction free properties

Shoulder, Olecranon, Knee

Question 11

Why is the name Osteoarthritis misleading

Answer 11

Because it is a disease of cartilage (chondro-) not a disease of bone (osteo-) like the name might suggest

Question 12

Osteoarthritis

Answer 12

Loss of articular cartilage and synovitis due to inflammation

Degenerative wear and tear condition

Question 13

Causes of osteoarthritis

Answer 13

Primary: Idiopathic

Secondary: Trauma, Inflammatory Disease, Joint Defects - that change distribution of stress at joints

Question 14

Risk factors of osteoarthritis

Answer 14

Age, Sex, Race, Bone Mass, Obesity

Question 15

Pathogenesis of Osteoarthritis

Answer 15

Amount of proteoglycans and collagen in cartilage reduce during age, while water increases causing ‘swelling’ and less shock absorbing

This causes surface cracks and the bone is exposed and they rub on each other, becoming burnished from wear

Fragments come away as it cracks, causing synovium to inflame
This leads to pain during movement of join

Question 16

Eburnation

Answer 16

the appearance of bone following a degenerative process in which subchondral or otherwise exposed bone acquires a “polished” articular surface

**YOU CAN IDENTIFY OSTEOARTHRITIS SKELETONS SINCE MANY OF THEIR BONES HAVE POLISHED SURFACES

Question 17

Osteophytes

Answer 17

Abnormal Bony Outgrowths that form during osteoarthritis

They limit the movement of the joint and can be quite painful

Question 18

Crepitation

Answer 18

Palpable or audible grating/crunching sensation produced by motion

Seen in osteoarthritis patients

Question 19

Discuss the changes that occur in early vs late osteoarthritis

Answer 19

In early stage, joint spaces narrow and start to crack as fragments are found in the joint capsule

In late phase, osteophytes also form and bony cysts start to form. Swelling is seen due to cartilage fragments as well as synovial inflammation
Bone/cartilage are eroded

Question 20

What is the key actor in causing osteoarthritis

Answer 20

A change in composition of the cartilage matrix to increase water and disrupt its ability to absorb shock

Question 21

Two diagnostic tests for Osteoarthritis

Answer 21

Crepitations
Narrowing of joint spaces seen on x-ray

**ALSO HISTORY

Question 22

Clinical Manifestations of Osteoarthritis

Answer 22

Pain
Limited Range of Movement
Swelling
Crepitation

Painful other joints as a result of compensation

Question 23

Where osteoarthritis is commonly seen

Answer 23

Lumnar and Cervical Spine

Proximal/Distal Hand Joints

1st Metatarsophalangeal Joint

Knee

Hip

Question 24

Treatment of Osteoarthritis

Answer 24

Rehabilitation
Drugs
Surgery

Question 25

How would osteoarthritis of the hand look

Answer 25

Question 26

Rheumatoiod Arthritis

Answer 26

Chronic systemic inflammation involving synovial joints with autoimmune causes due to a circulating antibody complex Complex forms with IgG to form immune complexes found in joint synovium, fluid & elsewhere Inflammation as result of macrophages and neutrophil reaction

Question 27

What type of joints are more targeted by Rheumatoid Arthritis

Answer 27

Peripheral Synovial Joints

Question 28

Sex Risk Factors of Rheumatoid Arthritis

Answer 28

2-3x women than men

Question 29

Symptoms of Rheumatoid Arthritis

Answer 29

``` Fatigue Anorexia Weight Loss Joint Aching/Stiffness Low Grade Fever Anaemia ```

Question 30

Why is the repair process damaging in rheumatoid arthritis

Answer 30

This process involves laying down collagen which ends up restricting movement

Question 31

Pannus

Answer 31

Hyperplasia of synovium and angiogenesis creating vascular granulation tissue (pannus)

Question 32

Ankylosis

Answer 32

Stiffening & Fusion of a joint

Question 33

Pathogenesis of Rheumatoid Arthritis

Answer 33

Unknown immune response causes synovial inflammation Neutrophils, Macrophages & Lymphocytes get recruited causing phagocytosis of immune complexes, releasing lysosomal enzymes Joint cartilage is destroyed and further inflammatory cells get recruited leading to vasodilation and thus redness & swelling Inflammtory cells in pannus destroy cartilage and bone cause ankylosis

Question 34

Ankylosis

Answer 34

Stiffening & Fusion of a joint

Question 35

Development of Rheumatoid Arthritis

Answer 35

Synovium is inflamed as result of antigen antibody complexes, they then destroy the cartilage and create pannus It is repaired leading to pannus being laid down while bone is erroded Since the bone is eroded, the body tries to then convert all the panus into bone, leading to ankylosis and bone fusion

Question 36

Clinical Manifestations of Rheumatoid Arthritis

Answer 36

***DONT MEMORISE

Question 37

What changes might be seen in the X-ray of a Rheumatoid Arthritis patient

Answer 37

Narrowing of the space is not likely to be seen, but if there is an ossification of the pannus then there may be evidence of this on the x-ray

Question 38

Discuss blood tests for Rheumatoid Arthritis Diagnosis

Answer 38

Serum Rheumatoid Factor It is positive in 80% of RA patients but positive in <5% of normal patients

Question 39

Differences between RA and OA

Answer 39

RA has more inflammation than OA and this is likely to be seen visibly and in blood RA patient may have positive serum rheumatoid factor Bony alkylosis may be seen in RA

Question 40

Gout

Answer 40

Crystal Arthropathy - Crystals of Uric Acid in Joint Space Uric acid arises from excess purine intake and lack of ability to break it down

Question 41

Primary Gout

Answer 41

Hyperuricaemia as result of underexcretion of uric acid from kidney

Question 42

Secondary Gout

Answer 42

Excess intake of foods with high purines like red meat

Question 43

Where do gout crytsals commonly form

Answer 43

MP Joint of big toe and in soft tissues

Question 44

Incidence of gout in male vs female patients

Answer 44

Higher in men

Question 45

Pseudogout

Answer 45

Aging cartilage degeneration - age related Osteoarthritis - calcium pyrophosphate crystals stack in joint cavity Common in elderly **DONT STRESS ON THIS

Question 46

***FOCUS MORE ON OSTEOARTHRITIS AND RA AS OPPOSED TO GOUT AND BURSITIS