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Flashcards in musculoskeletal system Deck (30)
1

Common Pathologies of Bone

Fractures
Osteoporosis
Arthritis
Osteomyelitis
Tumours

2

Fractures

Result of trauma

Can occur in healthy bone or in bone which is otherwise diseased eg. deposit of cancer in bone weakening the bone

3

Fracture treatment

Aim to realign bone to allow good function after healing.
This can be achieved with a plaster cast +/- surgery depending on the fracture

4

Fracture Healing

Immediately after fracture rupture of blood vessels causes haematoma which fills the fracture gap
This also provides a fibrin mesh work to allow formation of granulation tissue
Inflammatory cells release cytokines to activate osteoblasts and osteoclasts
Development of cartilage cap (callous) ~1week
Bone deposition begins to strengthen callous
Repair tissue reaches maximum girth ~2-3 weeks

5

Fracture Healing obstacles

If bones not aligned
If area not immobilised
If fracture site contains dead bone
Infection

6

Osteoporosis

Decrease in bone mass and density
Can lead to fractures
Very common – 3 million people in UK
Imbalance between bone resorption and bone production
Inadequate peak bone mass
Excess bone resorption
Inadequate bone production

7

Osteoporosis causes

Hormonal influences- lack of oestrogen (eg. post-menopausal) increases bone resorption and decreases new bone formation
Calcium metabolism and Vitamin D deficiency can also hinder bone formation

8

Osteoporosis treatment

NICE guidelines

Alendronic acid – bisphosphonate that prevents osteoclast activity

9

Arthritis

Arthritis’ means inflammation of a joint

Characterised by pain, swelling, stiffness
May be redness (erythema) and warmth over the joint
Restricted movement

‘Arthropathy’ means joint disease or disorder

10

Classification of Arthritis

OSTEOARTHRITIS
RHEUMATOID ARTHRITIS
Gouty Arthritis
Seronegative Spondyloarthropathies
- Ankylosing spondylitis
- Reactive arthritis
- Psoriatic arthritis
Infectious arthritis
Juvenile Idiopathic Arthritis
Arthritis secondary to systemic disease

11

OSTEOARTHRITIS

Most common
Associated with increasing age and obesity
Progressive deterioration
Usually in weight-bearing joints
Most cases primary – no initiating cause
Secondary – at any age with previous joint trauma or congenital abnormality

12

OSTEOARTHRITIS risk factors

Increasing age
Female sex, menopause
Obesity
Pre-existing joint deformity
Excess mechanical stress, e.g. professional sportspeople, miners, farmers
Genetic susceptibility or family history
Hypermobility
Other diseases (Secondary OA)

13

OSTEOARTHRITIS pathogenesis

'wear and tear’
Breakdown of articular cartilage
Underlying bone exposed
Fragments of cartilage can fall into the joint
Bony thickening and outgrowths (osteophytes) develop

14

features of OSTEOARTHRITIS

Morning stiffness
Pain, worse with movement
Reduced range of movement
Progressive reduction in mobility
Joint effusions (fluid)
Crepitus

15

Rheumatiod Arthiritis

Affects about 1% of the population
Women affected 3 times more than men
Familial association
Link with HLA (human leukocyte antigen)

16

Rheumatiod Arthiritis pathogenesis

Rheumatoid factors help form immune complexes in the circulation
Generates inflammation in the synovium
Membranes thicken
Chronic inflammation leads to cartilage and joint destruction
Other tissues involved eg. in lungs and vessels

17

Features of rheumatoid arthiritis

Usually affects small joints of hands and feet
Pain
Swelling and deformity
Fever, fatigue, generalised pain
Joints often stiff without prior activity
Most have fluctuating disease

18

Diagnosis of Rheumatoid arthiritis

Need 4 of:

Morning stiffness > 1 hour
Arthritis in 3 or more joints
Arthritis of typical hand joints
Symmetric arthritis
Rheumatoid nodules
Serum rheumatoid factor
Typical radiographic changes

19

Crystal Arthropathies

Associated with intra-articular crystal
formation
Gout
Pseudogout

20

Gout

Raised uric acid
Produced by breakdown of purine bases by the enzyme xanthine oxidase
Usually excreted by kidneys
Urate deposited as crystals in the joints
Repeated attacks lead to chronic arthritis
Causes: drugs (aspirin, diuretics), alcohol, renal disease, hypothyroidism, dehydration

21

features of gout

Sudden onset excruciating burning joint pain

Redness, warmth, tenderness, stiffness

Usually first attack involved big toe

Subsequent attacks are less severe

22

Pseudogout (Calcium pyrophosphate crystal deposition disease)

Precipitation of calcium pyrophosphate crystals in connective tissues
Crystals in cartilage can enlarge and rupture causing “crystal shedding” into joint cavity or soft tissues
inflammatory response and synovitis
Usually in knees and ankles

23

causes of Pseudogout (Calcium pyrophosphate crystal deposition disease)

Can be hereditary
Associated with osteoarthritis
Trauma or surgery
More common with increasing age

24

septic arthritis

Inflammation of a joint caused by bacterial infection
Commonly affects the knee
Causes severe pain, swelling, redness and heat in affected joints. These symptoms tend to develop quickly over a few hours or days.
May also have difficulty moving the affected joint and some people have a high temperature.

25

septic arthritis treatment

Needs treatment with IV antibiotics
May require washout of the joint
Can be very serious and cause sepsis

26

Osteomyelitis

Bone infection usually caused by bacteria
Trauma, surgery, presence of foreign bodies
Diabetics at increased risk

Haematogenous spread

27

Bone tumour

Commonest bone tumour is metastatic disease from a distant cancer eg. prostate, kidney, breast

Primary bone tumours are relatively rare
Benign: osteiod osteoma
Malignant: sarcoma

28

Striated Muscle

Skeletal muscle
Visible striations on microscopy
Involved in voluntary movements eg. biceps, muscles of arms and legs etc.

29

Smooth Muscle

Forms muscle layer in walls of GIT, ducts, arteries and internal organs
Involved in involuntary actions such as bowel peristalsis
Controlled by autonomic nervous system

30

pathology of muscle

Skeletal muscle - muscular dystrophies, neuromuscular disorders

Smooth muscle- leiomyomas