Injury & healing Flashcards
1
Q
What is a fracture?
A
A broken bone, it will heal whether or not a physician rests it in its anatomical position
2
Q
What will happen to the bone during a fracture if it is not rest correctly?
A
The healing process will rebuild new bone but keep the bone in its deformed position
3
Q
What is closed reduction?
A
Manipulation of broken bone, and set into natural position without surgical intervention
4
Q
What is open reduction?
A
Requires surgery to expose the fracture and reset the bone
5
Q
How are fractures classified?
A
Complexity
location
specific features
6
Q
What are the 6 types of fracture?
A
Transverse Oblique spiral comminuted impacted greenstick
7
Q
What is a transverse fracture?
A
Occurs straight across the long axis of the bone
8
Q
What is an oblique fracture?
A
Occurs at an angle that is not perpendicular
9
Q
What is a spiral fracture?
A
Bone segments are pulled apart as a result of twisting motion
10
Q
What is a comminuted fracture?
A
Multiple breaks result in many small pieces between two large segments
11
Q
What is classified as a simple comminuted fracture?
A
2 pieces
12
Q
What is an impacted fracture?
A
One fragment is driven into the other, as a result of compression
13
Q
What is a greenstick fracture?
A
Partial fracture in which one side of the bone is broken
14
Q
What is an open fracture?
A
A fracture in which at least one end of the bone penetrates the skin, presenting potential risk of infection
15
Q
What is a closed fracture?
A
A fracture in which the skin remains intact
16
Q
What are displaced bone fractures?
A
Occurs when bony ends are not aligned
17
Q
What is a stress fracture?
A
Repetitive application of forces on particular bone results in stress exertion on localised region -> Exceeds remodelling capacity causing bone weakening, stress fracture occurs
18
Q
When does a bone experience stress?
A
Whenever a force is loaded upon it (Pull of a muscle or shock of a weight bearing extremity contacting the ground)
19
Q
What does ADL mean?
A
Activities of daily living
20
Q
What happens to bone when a force is removed?
A
The bone elastically rebounds to its original position. The force that a bone can endure and rebound back without damage is referred to as being within the elastic range
21
Q
What are the weight baring bones?
A
Tibia, metatarsals, navicular
22
Q
What is the female triad?
A
1) Amenorrhoea
2) Osteoporosis
3) Disordered eating
23
Q
Why does osteoporosis increase risk of fractures?
A
Reduced bone mineral density, increasing porous structure
24
Q
What are the pathological causes of fractures?
A
Osteoporosis Malignancy Vitamin D deficiency Osteomyelitis Osteogenesis imperfecta Paget's disease
25
What does vitamin D deficiency do to bone?
Osteomalacia + ricket's
26
What are the 3 mechanisms of actions for fractures?
Pathological
Stress
Trauma
27
What is a trauma fracture?
Low energy and high energy transfer to bone
28
What is a stress fracture?
Abnormal stresses on normal bone
29
What is a pathological fracture?
Normal stresses on abnormal bone
30
What type of fracture is common for patients with osteoporosis?
Low energy trauma
31
How does osteoporosis and osteopenia occur?
Bone remodelling imbalance, bone resorption (osteoclast activity) > bone formation (osteoblast activity)
32
Which ligand is a mediator of osteoclast activity?
RANKL
33
What is the ratio for osteoporosis incidences between females: males?
4:1
34
When is the average age range for senile osteoporosis?
> 70
35
What is secondary osteoporosis typically associated with?
Hypogonadism
Glucocorticoid excess
alcoholism
36
What are the three most common fragility fractures?
Wrist, hip and spine
| Low energy trauma
37
What T score is equivalent to osteoporosis?
-2.5
38
What T score range is diagnostic of osteopenia?
-1 --> -2.5
39
Why does menopause cause osteoporosis?
Oestrogen deficiency contributes towards excessive bone resorption. Osteoblasts, osteocytes, and osteoclasts express oestrogen receptors on their cell-surface membrane.
Function: Oestrogen prevents bone loss through the inhibition of osteoclastic bone resorption.
Oestrogen indirectly causes the increased production of transforming growth factor-beta that enhances osteoclast apoptosis. In the absence of oestrogen, T cells promote osteoclast recruitment ,and prolonged survival of interleukin-1, IL-6, and TNF-⍺. IL-6 contributes to the recruitment of osteoclasts.
Osteoblasts secrete IL-6 involved in osteoclast activation.
Post-menopausal women therefore exhibit an oestrogen deficiency, consequently stimulating osteoclastic activity due to a reduction in inhibitory effect, leading to osteoporosis.
40
What are the main examples of lytic cancers?
Breast, kidney, thyroid and lung
41
Which type of cancer has the ability to metastasis bone?
Lytic cancers (breast, kidney, thyroid and lung)
42
What are lytic cancers associated with?
Associated with reduction in size --> Referring to thinning and bone degradation
43
What are plastic cancers associated with?
Hyperplasia and hypertrophic mechanisms
44
What are the four main primary bone cancers?
Osteosarcoma
Chondrosarcoma
Ewing sarcoma
chroma
45
What pathology is associated with pre-epiphyseal closure vitamin D deficiency?
Rickets
46
What pathology is associated with post-epiphyseal closure vitamin D deficiency?
Osteomalacia
47
What are the consequences of a calcitriol deficiency?
reduced calcitriol activity Hypocalcaemic conditions (Reduced Ca2+ absorption, renal reabsorption, & hyperparathyroidism)
48
What is the inheritance pattern of osteogenesis imperfecta?
hereditary - autosomal dominant/recessive
49
Which type of collagen is reduced in osteogenesis imperfecta?
Type 1 collagen
50
What is the function of collagen?
Collagen is an extracellular matrix protein secreted by fibroblasts & osteoblasts, and organised into insoluble fibres, comprising the extracellular matrix surrounding cells Provides mechanical strength & rigidity to tissues and organs, especially to skeletal tissues: Bone, cartilage, tendons & ligaments.
51
What is the main feature of osteogenesis?
Reduced fracture of long bones
52
What is the aetiology of Paget's disease?
Genetic and acquired factors
53
What is Paget's disease?
Excessive bone degradation and disorganised bone remodelling -> Deformity, pain fracture, or arthritis. May transform into malignant disease
54
What are the four stages of Paget's disease?
1) Osteoclastic activity (increased bone resorption)
2) Mixed osteoclastic - osteoblastic activity (imbalance) results in disorganised bone remodelling, considering the osteoid scaffold is disrupted., and diverted through osteoclastic activity --> deformities arises
3) Osteoblastic activity
4) Malignancy degeneration
55
What three main factors influence fracture healing?
Depends on type, severity, and distance between bone fragments
56
What is direct bone healing?
Bones may heal directly by constructing new bone onto the fracture site -> Bone remodelling associated with osteoclast & osteoblast activity
57
What is the first step of fracture healing?
Bleeding/haematoma
58
What is a haemtoma, and the first stage of fracture healing associated with?
Prostaglandin/cytokine released; growth factors increase local blood flow --> Periosteal supply dominates
59
Which blood supply dominates within step 1 fracture healing?
Periosteal supply
60
When does step 1 fracture healing occur?
Week 1
61
When does step 2 fracture healing occur?
Week 2-4
62
What happens during step 2 fracture healing?
Granulation (connective/fibrotic) tissue deposited --> Soft callus (Type II collagen) -> cartilage; fibroblasts, woven bone (immature bone)
63
What forms during step 2 fracture healing?
Soft callus
64
Which type of collagen forms the soft callus?
Type 2 collagen
65
What happens during step 3 fracture healing?
Fracture is bridged with soft callus --> Hard callus formation succeeds (laying down of osteoid --> type 1 collagen) facilitated by increased osteoblast activity
66
When does step 3 fracture healing occur?
1-4 months
67
When does stage 4 fracture healing occur?
4-12 months
68
How is bone remodelled during stage 4 fracture healing?
Endochondral ossification
69
What happens during stage 4 fracture healing?
Bone is remodelled through endochondral ossification lamellar bone in its place. Callus responds to activity, external forces, and the functional demands exerted onto bone; therefore this stimulates a balance of osteoblast & osteoclast activity to remodel bone (removal of excess).
70
What re the four stages of fracture healing?
Haemtoma
Soft callus
hard callus
remodelling (endochondral ossification, osteoblast activity lamellar bone is integrated).
71
What does Wolff's Law state?
Wolff’s Law: States that bone grows and remodels in response to the forces that are exerted onto it. Placing specific stress in specific directions stimulates osteocyte activity.
Osteocyte apoptosis during disuse.
72
What is primary bone healing associated with?
Intermembranous healing
73
Which type of bone healing, primary or secondary is associated with absolute stability?
Primary bone healing
74
What are the three main phases of primary bone healing?
Inflammatory phase
Reparative phase
remodelling phase
75
Which cells are mainly involved in primary bone healing?
Osteoblasts
76
Why is primary bone healing faster?
Osteoblasts move into fracture. In primary bone healing, the bone ends are in contact , osteoblasts can traverse across, and bone formation is accelerated, membrane forms. Membrane formation behaves as a conduit for osteoblasts to pass
77
What is the inflammatory phase of pone healing?
Broken bones result in disrupted blood vessels, thus formation of a blood clot & haematoma. Inflammatory reaction results in cytokine release, growth factors & prostaglandins.
Fracture haematoma becomes organised and infiltrated by fibrovascular tissues, forming matrix for bone formation & primary callus
78
What factors are released during the inflammatory phase of bone healing?
Cytokine ,prostaglandins, and growth factors
79
What structure forms during the inflammatory phase of primary bone healing?
Primary callus
80
What is the approximate duration of the inflammatory phase?
Duration: Hours - days
81
Where does the thick mass callus form during the reparative phase of bone healing?
Around bone ends
82
Which cells are recruited during the reparative phase of bone healing?
Osteoblasts are recruited to deposit type 1 collagen, derived from osteoid
83
When is bone healing evident on radiographs?
7-10 days
84
What happens during the reparative phase to the soft callus?
Soft callus transforms into hard callus
85
What is a soft callus?
Plastic, easily performed or bend, if the fracture is not adequately supported
86
What is a hard callus?
Weaker in comparison to normal bone
| Better capability to withstand external forces to the stage of clinical union
87
What is the stage of clinical union in terms of bone healing?
Fracture is not tender to palpation or with movement
88
Which phase of bone healing is the longest?
Remodelling phase
89
What is the average duration of the remodelling phase of bone healing?
Months-years
90
During remodelling which law is obeyed?
Wolf's Law
91
How is the external callus removed during the remodelling phase of bone healing?
The external callus is no longer required, therefore is removed through osteoclast activity, and fracture site is smoothed & sculpted
92
In which phase of bone healing is the epiphyses realigned and residual angulation corrected?
Remodelling
93
What type of healing is associated with secondary bone healing?
Endochondral healing
94
Which responses are involved in endochondral healing?
Involves responses in the periosteum and external soft tissue --> Relative stability
95
Why is secondary bone healing less effective than primary bone healing?
Osteoblasts cannot jump across the gap. Cells derived from the periosteum causes osteoblasts to form osteoid, this bone formation joins the bone - cartilage precursor. Bone formation is unregulated, thus callus formation occurs
96
What is the average healing time?
3-12 weeks depending on site
97
What is the average length of time for phalange healing?
3 weeks
98
What is the average length of time for metacarpal, healing?
4-6 weeks
99
What is the average length of time for distal radius healing?
4-6 weeks
100
What is the average length of time for forearm healing?
8-10 weeks
101
What is the average length of time for femur healing?
12 weeks
102
What is the average length of time for tibia healing?
10 weeks
103
What is reduction in terms of fracture management?
Reduction involves restoring the anatomical alignment of a fracture or dislocation of the deformed limbs
Main principle: Correct the deforming forces that results in the injury
104
What is the first stage of fracture management?
Reduction
105
How is fracture reduction performed?
Performed closed,
106
Why is reduced swelling an important concern during fracture management?
Reduction traction on the surrounded tissue causes reduced swelling, swollen soft tissue have high rates of wound complications
107
What is the main aim of reducing traction on the traversing nerves?
Reduces neuropraxia
108
What is the main aim of reducing pressure on blood vessels?
Restoration of affected vasculature
109
What are the four main stages of fracture management?
Reduction
Hold
Fixation
Rehabilitation
110
What is associated with hold during fracture management?
Describes fracture immobilisation, important to consider whether traction is required, whereby the muscle pull across the fracture site is strong, and the fracture is inherently unstable
111
What clinical devices are usually implemented to immobilise fractures?
Plaster castes
| Simple splints
112
Why should an overlying dress be applied to the fracture site?
Enables fracture to swell
113
What is the main risk if an overlying dress is not applied to the fracture site?
Patient may develop compartment syndrome
114
What is axillary instability?
Fracture is able to rotate along its long axis
| The plaster should cross both joint above and below
115
What is the stabilisation stage of fracture management?
Fixation
116
What are the two categories to fixate a fracture?
Internal (intramedullary nails, and screws)
| External fixation
117
What does the rehabilitation phase involve during fracture management?
Refers to the requirement for majority of patients to undergo an intensive period of physiotherapy following fracture management.
Advised that patients move from non immobilised unaffected joints from the outset
118
What is tendinitis?
Inflammation of tendon associated from overuse (In addition to infection or rheumatic disease). Swelling, and pain results in reduced mobility of tendon & muscle.
119
What is tedinosis?
Chronic conditions involving deterioration of collagen within tendons. Tendinosis is caused by overuse of a tendon --> Abnormal thickening
120
What are the three main pathologies involved with tedinopathy?
Tendinitis
Tendinosis
Ruptured tendon
121
What are the three grade classifications of ligament injury?
Grade 1, II, III
122
What is a grade I ligament injury?
Slight incomplete tear
| No notable joint instability
123
What is a grade II ligament injury?
Moderate/severe incomplete tear --> Some joint instability. One ligament may be completely torn
124
What is a grade III ligament injury?
Complete tear of 1 or more ligaments, there is an obvious indication of instability
Surgical intervention required
125
What is the main pathology for the inflammatory phase of bone healing?
Fibrin clots formed in ligament tears
126
What is the main pathology during the proliferation phase of bone healing?
Tendons & ligaments weakest, ensile strength builds
127
Which bone healing phase is the most painful?
Inflammatory phase
128
What is the main advantage of immobilisation?
Less ligament laxity (lengthening)
129
In terms of strength which is better, mobilisation or immobilisation of ligamentous tissue?
Mobilisation results in grater overall strength
130
What are the 5 main disadvantages for immobilisation of ligamentous tissue?
```
Less overall strength
Protein degradation
Production of inferior tissue Bly blast cells
Bone resorption
Build tissue tensile strength
```
131
What are the 2 main benefits of mobilising ligamentous tissue?
Ligament scars are wider, stronger & more elastic
| Better alignment/quality of collagen
