Muskoskeletal disorders

Question 1

What are causes of fractures?

Answer 1

Trauma: high or low energy
Stress: abnormal stresses on normal bone
Pathological: normal stresses on abnormal bone

Question 2

How is soft tissue integrity affected by fractures?

Answer 2

Open- bone has broken through skin

Closed- skin not broken

Question 3

What are different ways bones can break?

Answer 3

Greenstick- incomplete fracture where bone is bent, occurs most often in children
Simple- fracture of the bone only without damage to surrounding tissues or breaking of skin
Comminuted- bone breaks in several places

Question 4

How can the displacement of a bone be classified?

Answer 4

Displaced- bone breaks in 2 or more pieces and moves out of alignment
Undisplaced- bone breaks but doesn’t move out of alignment

Question 5

What causes a stress fracture?

Answer 5

Stress exerted on bone is greater than bone capacity to remodel
Bone weakening leads to stress fracture which can lead to a risk of incomplete fracture
Occurs on weight bearing bone

Question 6

In what specific type of individual may a stress fracture be common in?

Answer 6

Young female athlete

Females athlete triad: interrelationship between amenorrhea, disordered eating and osteoporosis

Question 7

What does Wolff’s law tell us about fracture healing?

Answer 7

Bone grows and remodels in response to forces placed upon it

Question 8

How long does a fracture take to heal?

Answer 8

takes 3-12 weeks depending on site

Signs of visible healing on x-ray from 7-10 days

Question 9

What are the steps to a fracture healing?

Answer 9

1. Inflammation (week 1): haematoma formation, release of cytokines, granulation tissue
2. Repair (week 2-4): soft callous formation (type II collagen) converted to hard callous (type I collagen) (1-4 months)
3. Remodelling (4-12 months): callous responds to activity, external forces, functional demands and growth. Excess bone is removed

Question 10

What are pathological disorders that affect bone?

Answer 10

1. Osteopenia
2. Osteoporosis
3. Malignancy
4. Vitamin D deficiency (osteomalacia/ rickets)
5. Osteomyelitis (bone infection)
6. Osteogenesis imperfecta
7. Padgets disease

Question 11

What is osteopenia?

Answer 11

Protein and mineral contents of bone tissue is reduced but less severely than osteoporosis

Question 12

What is osteoporosis?

Answer 12

Disease characterised by low bone mass and structural deterioration of bone tissue with consequent increase in bone fragility and susceptibility to fracture
Caused by osteoclast activity > osteoblast structure
Most common in females
Secondary osteoporosis can occur at any age. Can be due to hypogonadism, glucocorticoid excess, alcoholism

Question 13

How do we diagnose osteoporosis and osteopenia?

Answer 13

A t score is used to diagnose- this is standard deviations from the mean using bone mass as unit
T>-1 = normal bone
T -1 - 2.5 = osteopenia
T

Question 14

how does malignancy cause fractures?

Answer 14

Primary bone cancers inc. : osteosarcoma, chondrosarcoma, Ewing sarcoma, chondroma
Can also get primary tumours in other parts of the body that metastasise to bone inc. prostate, kidney, breast, thyroid and lung

Question 15

How does vitamin D deficiency cause fractures?

Answer 15

Rickets = paediatric consequence of vitamin D deficiency. Occurs before physis closure. Can cause bowing of tibia/legs
Osteomalacia= adult consequence of vit. D deficiency. Occurs after physis closure. Symptoms inc. weaker bones, pain and tenderness

Question 16

What is osteogenesis imperfecta?

Answer 16

Brittle bone disease
Its autosomal dominant or recessive
Decreased type I collagen due to: decreased secretion or production of abnormal collagen
Results in insufficient osteoid production

Question 17

What is padgets disease?

Answer 17

Can be caused by genetic or acquired factors
Excessive bone breakdown and disorganised modelling- deformity, pain, fracture or arthritis
May transform into a malignant disease
4 stages:
1. Osteoclastic activity
2. Mixed osteoclastic- osteoblastic activity
3. Osteoblastic activity
4. Malignant degeneration
Rushed bone building leads to woven rather than lamellar patterns

Question 18

What are the different types of bone healing?

Answer 18

Primary bone healing:
- intramembranous healing
- absolute stability 
- direct to woven bone
Secondary bone healing:
- endochondral healing
- involves responses in periosteum and external soft tissues
- relative stability
- classical stages of healing: inflammation, repair, remodelling

Question 19

What are the 4 ways of managing fractures?

Answer 19

Reduction
Hold
Fixation
Rehabilitate

Question 20

What is reduction?

Answer 20

Realignment of bone to prevent deformities
Open: surgical incision made to expose fragments and put them back into proper position - can be done by mini- incision or full exposure
Closed: displaced or fractured bone fragments manipulated back into proper position or alignment without surgery - can be done by manipulation or traction (hang weight of injury)

Question 21

What is holding?

Answer 21

Choosing how to hold the fracture
Can be done by fixation or Closed
Closed includes plaster or traction

Question 22

What is fixation?

Answer 22

Stabilising the fractured bone
External- metal outside bone. Includes monoplane or multiplane
Internal: metal underneath skin. Includes intramedullary (pins and needles) or extramedullary (plates/screws and pins)

Question 23

What does rehabilitation include?

Answer 23

Use
Move
Strengthen
Weight-bear

Question 24

What is a soft tissue injury?

Answer 24

Injury to muscles, ligament or tendons

Question 25

What is tendinopathy?

Answer 25

Injury of tendon. Includes:

• Tendinosis (abnormal thickening)
• Tendinitis (inflammation)
• Rupture

Question 26

How are ligament injuries classified?

Answer 26

Grade I: slight incomplete tear- no notable joint instability
Grade II: moderate/severe incomplete tear- some joint instability, one ligament might be completely torn
Grade III: complete tearing of 1 or more ligaments, obvious instability, surgery usually required

Question 27

What are common ligament injuries?

Answer 27

ACL tears and Achilles tendon tears

Question 28

How do soft tissue injuries heal?

Answer 28

Inflammation: fibrin clot formed in ligament tears
- treatment implications: RICE (rest, ice, compression, elevate), ROM exercises
Proliferation: tendons and ligaments weakest, tensile strength builds
- TIs: full ROM and WB exercises
Remodelling: tendons and ligaments heal with scar tissue that reduces ultimate tensile strength
-TIs: build strength
Maturation: Max strength reached within a year

Question 29

What are the effects of immobilisation?

Answer 29

Pros:
-Less ligament laxity
Cons:
-Less overall strength of ligament repair scar
-Protein degradation exceeds protein synthesis
-Production of inferior tissue by blast cells
-Resorption of bone at site of ligament insertion

Question 30

What are effects of mobilisation?

Answer 30

Pros:

• Ligament scars are wider, stronger and more elastic
• Better alignment/quality of collagen