Osteoarthritis

Question 1

Define osteoarthritis

Answer 1

Progressive disorder of the joints caused by a gradual loss of cartilage and resulting in the development of bony spurs and cysts at the margin of the joints.

Question 2

What is the function of an articular/fibrous cap?

Answer 2

Stabilises the joint and keeps it in place

Question 3

Functions of synovial fluid?

Answer 3

Supplies nutrients to the cartilage
Removes metabolic waste products
Lubricates and reduces friction between bones of a joint
Phagocytic cell remove debris

Question 4

Describe the characteristics of a joint affected by osteoarthritis

Answer 4

Narrowing of joint space
Subluxation (partial disclocation)
Osteophyte formation (bony spurs)
Subchondral sclerosis (whiteness below cartilage)
Sub articular cyst formation
Capsule become inflamed and thickens
Fibrillated cartilage - cartilage softens and forms vertical clefts
Synovial hypertrophy - synovial membrane thickens
Altered shape/contour of bone

Question 5

Draw a normal and osteoarthritic joint

Answer 5

osteophyte (bony spurs - extra bone growth)
Thick synovial membrane
Thinner layer of cartilage
Narrowed joint space
Fibrillated cartilage = vertical clefts
subchondral sclerosis 
sub articular cyst 
thickened and inflamed capsule

Question 6

what is articular cartilage?

Answer 6

Hyaline cartilage that is found on the articular surface of bones

Question 7

List 4 changes that occur to cartilage due to OA

Answer 7

Cartilage Fibrillation: formation of vertical clefts
Cartilage erosion
Cartilage swelling
Change in colour

Question 8

What are three types of cartilage

Answer 8

hyaline/articular
Fibrocartilage
Elastic

Question 9

Give examples of where hyaline cartilage is found

Answer 9

sternal ends of ribs, epiphyseal growth plate, articular surfaces, embryonic skeleton

Nose (nasal septum), tracheal rings, larynx

Question 10

What fibres does elastic cartilage have? Give examples of where elastic cartilage is found

Answer 10

Elastic fibres

Ear (external and auditory tube), epiglottis

Question 11

Give examples of where fibrocartilage is found

Answer 11

Meniscus
IV disc
Pubic symphysis
Sternoclavicular joint

Question 12

Describe the pathogenesis of OA

Answer 12

Decrease in:
water content
proteoglycans
Collagen X-linking
size of aggrecan, GAG and hyaluronic acid

Traumatic damage

Question 13

What are the two types of OA and list some causes of them

Answer 13

Primary: degenerative disorder
Secondary: congenital abnormality (hip dysplasia), trauma, infection (can destroy bone and cartilage), diabetes (if poorly controlled )

Question 14

List systemic and biomechanical risk factors for OA

Answer 14

Systemic:
Old age
Gender (women)
Small genetic proportion 
Nutritional (low vitamin D or C intake)

Biomechanical:
obesity
trauma
occupation (heavy manual work)

Question 15

What are 3 key symptoms of OA

Answer 15

short-lived joint stiffness for less than 30 minutes in the morning
Pain when doing load-bearing activities (walking)
Difficulty moving effected joints

Question 16

What are 5 clinical signs ofOA

Answer 16

Pain 
Decreased walking distance
sleep disturbance
Limp - trendelenburg sign (when they rest on one leg, their hip abductors don't support them)
Stiffness

Question 17

List four changes due to OA seen in a joint on X-ray

Answer 17

Joint space narrowing
Subchondral sclerosis
Cyst formation
Osteophyte (bony spurs, exta bit of bone)

Question 18

List the non-operative treatments available for OA

Answer 18

Medications
Physiotherapy
walking aid
Joint injections

Question 19

Describe what medications are given for OA

Answer 19

Pain management: Paracetamol, NSAIDs - ibuprofen, diclofenac

Alternative medication: not clinically proven but patients say they work e.g. glucosamine and chondroitin sulfate

Question 20

Describe the use of physiotherapy for OA

Answer 20

weight loss

Exercises for increasing range of motion, strengthen and condition muscles

Question 21

Describe how use of a walking aid can be effective for OA

Answer 21

Transfers load to unaffected side, reduces load on joint so less pain

Question 22

Describe the use of joint injections to treat OA and the types available

Answer 22

Provides short term pain relief
Steroid injection: reduces inflammatory response around joints (more rapid than NSAIDs)
Viscous supplement: (no evidence but patients still use it) Synthetic synovial fluid is injected into joints to increase viscosity and elasticity of fluid

Question 23

list the surgical treatment available for OA

Answer 23

Arthroscopy
Cartilage transplantation
Joint replacement

Question 24

Describe arthroscopy

Answer 24

Micro fracturing process which involved breaking through subchondral bone below cartage to stimulate fibrotic response of cytokines and healing with fibrocartilage

Question 25

describe cartilage transplantation

Answer 25

only used in younger population <30

cartilage form one area is transferred to another area.

Question 26

Describe joint replacement surgery

Answer 26

removes worn cartilage and replaces it with synthetic material
replaces femoral component
key objective is pain relief and increased range of motion