Ortho OSCE Topics Flashcards
(161 cards)
1
Q
Which 4 areas are often affected by compartment syndrome?
A
Elbow (supracondylar #) Forearm bones (proximal) Proximal 1/3 of the tibia Foot Scapula
2
Q
Name causes of compartment syndrome
A
Intracompartmental
- fracture
- reperfusion injury
- crush injury
- ischemia
Extracompartmental
- constrictive dressing
- poor position during surgery
- circumferential burn
3
Q
How is compartment syndrome diagnosed?
A
1st sign = paraesthesia 2nd = pain out of proportion 3rd = pain on passive stretch Woody, hard swelling of the compartment Suspicious history
4
Q
How does compartment syndrome result in paraesthesia?
A
Compression of the small aa that supply the nerve
5
Q
What is pain out of proportion?
A
Not resolving after splinting Adequate analgesia (morphine, tramadol, perfalgan)
6
Q
How do you test pain on passive stretch in the lower limb?
A
Flex the big toe
7
Q
Which compartment is first affected in the lower limb?
A
Anterior compartment
8
Q
How do you test pain on passive stretch in the upper limb?
A
Extension of the fingers
9
Q
Which compartment is usually affected in compartment syndrome of the upper limb?
A
Flexor compartment
10
Q
Name the classic features of compartment syndrome
A
- Paraesthesia
- Pain out of proportion
- Pain on passive stretch
- Pallor
- Paralysis
- Pulselessness
11
Q
What investigations do you do in compartment syndrome?
A
It is a clinical diagnosis therefore investigations are usually not necessary
12
Q
How do you diagnose children or unconscious patients with compartment syndrome as clinical exam is unreliable?
A
Compartment pressure monitoring with catheter
13
Q
What is the normal compartment pressure?
A
0mmHg
14
Q
What compartment pressure suggests compartment syndrome?
A
Pressure >30mmHg
OR
DBP - pressure <30mmHg
15
Q
Discuss the non-operative management of compartment syndrome
A
Decompress threatened compartments - cut casts, bandages, dressing - split the splint bandages to keep fracture stable - cut circular POP on both sides Keep limb at the level of the heart Wait 20-35min and repeat examination - improvement = continue - no improvement = fasciotomy
16
Q
Why should you keep the limb at the level of the heart in compartment syndrome?
A
Decreases end capillary pressure which aggravates the muscle ischemia
17
Q
Discuss operative management of compartment syndrome
A
Surgically open the compartment
Leave the wound open and inspect 48-72h later
If muscle necrosis -> debridement
If healthy tissues -> suture wound without tension or use skin graft
18
Q
How do you do a fasciotomy of the leg?
A
Open all 4 compartments through medial and lateral incisions
19
Q
How long does it take for muscle necrosis to occur?
A
4-6h of total ischemia
20
Q
Name complications of compartment syndrome
A
Volkmann’s ischemic contracture
Rhabdomyolysis
Renal failure secondary to myoglobinuria
21
Q
Define an open fracture
A
Fractured bone and hematoma in communication with the external/contaminated environment
22
Q
Discuss the acute management of open fractures
A
- ABCs
Primary survey
Resus - Control bleeding with direct pressure
- Remove obvious foreign material
- Irrigate with normal saline if grossly contaminated
- Cover wound with saline soaked sterile dressings
- IV antibiotics once diagnosis of open fracture is confirmed
- coamoxiclav
- cefuroxime
- clindamycin - Tetanus toxoid if previously immunized
Tetanus immunoglobulin if not previously immunized - Reduce bone/joint
- Splint the limb until surgery
- NPO and preparation for theater
- bloods
- consent
- ECG
- CXR - Monitor state of soft tissues and neurovascular supply
23
Q
What are the 4 essentials of open fracture care?
A
Antibiotic prophylaxis
Prompt wound debridement
Fracture stabilization
Early definitive wound cover
24
Q
How are open fractures classified?
A
Gustilo Anderson classification
25
Discuss the Gustilo Anderson classification
```
Grade I
- <1cm long
- minimal soft tissue injury
- simple, low-energy fracture
Grade II
- >1cm long
- moderate soft tissue injury w/ some mm damage
- moderate comminution
Grade IIIA
- >1cm long
- extensive soft tissue injury with adequate ability of soft tissue to cover wound
- high-energy fracture, comminuted
Grade IIIB
- >10cm long
- severe loss of soft tissue cover
Grade IIIC
- >10cm long
- severe loss of soft tissue cover with vascular injury
```
26
Which antibiotic do you give for a Gustilo Anderson grade I and II?
1. 1st gen cephalosporin (cefazolin) 2g IV q8h 2d
2. Allergy = clindamycin 900mg IV tds
3. MRSA + = vancomycin 15mg/kg IV bd
27
Which antibiotic do you give for a Gustilo Anderson III?
1. 1st gen cephalosporin (cefazolin) 2g IV q8h 2d plus gentamicin/ceftriaxone for 3d
2. Metronidazole w/wo penicillin G for soil/fecal contamination
3. MRSA + = vancomycin 15mg/kg IV bd
28
Discuss the post-acute management of open fractures
```
Operative irrigation and debridement within 6-8h and repeat 24-48h until wound viable
External fixation
Wound dressing
- vac
- antibiotic bead pouch
Delayed wound closure within 3-7d
```
29
Define osteomyelitis
Bone infection with progressive inflammatory destruction
30
What is the most common mechanism of paediatric osteomyelitis?
Hematogenous seeding of bacteria to metaphyseal region of bone
31
How do you diagnose acute hematogenous osteomyelitis?
Kocher criteria
32
Discuss the Kocher criteria
1. Non-weight bearing on affected side
2. ESR>40mm/hr
3. Fever
4. WBC>12000
```
Probability:
4/4 = 99%
3/4 = 93%
2/4 = 40%
1/4 = 3%
```
33
How does acute haematogenous osteomyelitis present clinically?
Non-weight bearing on affected side
Fever
Bone tenderness on palpation
34
What investigations should you perform in acute hematogenous osteomyelitis?
```
XR to exclude fractures
Bloods
- ESR
- CRP
- WCC
```
35
How do you manage acute hematogenous osteomyelitis?
Refer to orthopaedics
No antibiotics
Drain pus
Send pus for MCS
35
How do you manage acute hematogenous osteomyelitis?
Refer to orthopaedics
No antibiotics
Drain pus
Send pus for MCS
36
Why do we not give antibiotics in acute osteomyelitis?
Patient is presenting with clinical signs therefore past bone oedema phase and in abscess phase, therefore manage as an abscess
37
What is the most common organism involved in acute osteomyelitis?
Staph aureus
38
Name risk factors for acute osteomyelitis
```
Recent trauma
Recent surgery
Immunocompromised
Haemoglobinopathy
RA
Chronic renal disease
IV drug use
Microvascular disease
Peripheral neuropathy
```
39
What are the mechanisms of acute osteomyelitis spread?
Haematogenous
Direct inoculation
Contiguous focus
40
Name XR findings in osteomyelitis
```
Early
- normal
- loss of soft tissue planes
- soft tissue oedema
- new periosteal bone formation 5-7d
- osteolysis 10-14d
Late
- metaphysical rarefaction
- abscess
- mottled, non-homogenous, moth eaten appearance
```
41
What occurs in chronic osteomyelitis after the area of bone has been destroyed by acute infection?
Sequestra surrounded by dense sclerosed bone which provoke chronic seropurulent discharge which escape through sinus at the skin surface
42
Define sequestrum
Dead bone
43
How does sequestrum appear on XR?
Sclerotic (more white)
44
Define involucrum
New bone formation around dead bone to protect the bone from breaking
45
Define a sinus
A hole in the skin draining fluid
46
What is a "sinus" in the bone cortex called?
Cloaca
47
Define a fracture
A break in the continuity of the bone cortex
48
Name the red flags of back pain
```
BACK PAIN
Bowel/bladder dysfunction
Anesthesia (saddle paresthesia)
Constitutional symptoms
Khronic disease
Paresthesias
Age >50yo or <15yo
IV drug use
Neuromotor deficits
```
```
Other:
Weight loss
Pain at night, while sleeping, at rest
Morning stiffness
Sensory loss
Fever
Cancer history
Hypercalcemia
```
49
What questions should be asked on history in back pain?
SOCRATES
```
Site
Onset
Characteristics
Radiation
Associated symptoms
Time
Exacerbating/relieving factors
Severity
```
50
Define wrist drop
Inability to extend the wrist and the fingers at the metacarpophalangeal joints
51
Which nerve is affected in wrist drop?
Radial nerve (high lesion)
52
Name causes of high lesions of the radial nerve
Humeral fracture
Prolonged tourniquet
Saturday night palsy
53
Which muscles are affected in wrist drop?
Wrist extensors
1. Extensor carpi radialis longus
2. Extensor carpi radialis brevis
3. Extensor carpi ulnaris
4. Extensor digitorum
5. Extensor digiti minimi
54
Which nerve is affected in foot drop?
Common peroneal/fibular nerve
55
Define foot drop
Weak dorsiflexion and eversion of the foot resulting in tendency to trip and fall while walking
56
Which muscles are affected in foot drop?
Tibialis anterior
Extensor hallucis longus
Extensor digitorum longus
Fibularis tertius
57
Name mechanisms of injury of the axillary nerve
Proximal humerus fracture
Humeral neck fracture
Shoulder dislocation
58
How do you examine the motor function of the axillary nerve?
Isometric deltoid contraction
| Place hand on the lateral side of the injured arm to prevent movement and other hand on the deltoid to feel contraction
59
How do you examine the sensory function of the axillary nerve?
Numbness over the deltoid
| Difficult to test due to pain
60
Name mechanisms of injury to the radial nerve
```
Very high lesion
- crutch palsy
High lesion
- humeral fracture
- prolonged tourniquet pressure
- Saturday night palsy
Low lesion
- elbow fracture
- elbow dislocation
```
61
How do you examine the motor function of the radial nerve?
Very high lesion:
Triceps paralyzed and wasted
High lesion:
Wrist extension
Thumbs up
Low lesion:
Metacarpophalangeal joint extension
62
How do you examine the sensory function of the radial nerve?
Dorsum of the 1st web space
63
Name mechanisms of injury to the median nerve
```
High lesion
- supracondylar fracture
- elbow dislocation
Low lesion
- carpal dislocation
- cuts in the front of the wrist
```
64
How do you examine the motor function of the median nerve?
High lesion:
O sign
Index DIP flex for positive benediction sign
Low lesion:
Thumb abduction
65
What is the purpose of the O sign?
Flexor pollicus and deep flexor of index finger supplied by anterior interosseous nerve
66
What is the innervation of the abductor pollicis muscle?
Recurrent thenar br of median nerve
67
Which test for the median nerve is not applicable in a distal radius fracture?
O sign
68
How do you examine the sensory function of the median nerve?
Pulp of the index finger
69
Name the mechanisms of injury of the ulnar nerve
High lesion
- elbow fracture
Low lesion
- wrist pressure/laceration
70
How do you examine the motor function of the ulnar nerve?
On a flat surface, finger abduction and adduction
| Froment's test
71
How do you examine the sensory function of the ulnar nerve?
Ulnar side of little finger
72
Explain Froment's test
Ask patient to hold piece of paper in hands between thumb and index fingers to test adductor pollicis
If test is positive, patient will acutely flex in IPJ of the thumb because flexor pollicis longus is supplied by median nerve
73
Name the mechanisms of injury of the femoral nerve
Anterior hip dislocation
| Gunshot wound
74
How do you examine the motor function of the femoral nerve?
Knee extension (anterior thigh compartment)
75
How do you examine the sensory function of the femoral nerve?
Anterior thigh
| Medial aspect of leg
76
Name the mechanisms of injury of the sciatic nerve
Posterior hip dislocation
| Hip replacement
77
How do you examine the motor function of the sciatic nerve?
All muscles below the knee eg foot dorsiflexion
78
How do you examine the sensory function of the sciatic nerve?
Majority of the leg
79
Name the mechanisms of injury of the common peroneal nerve
Fibular neck fracture
80
How do you examine the motor function of the common peroneal nerve?
Foot dorsiflexion
Foot eversion
Drop foot
81
How do you examine the sensory function of the common peroneal nerve?
Anterolateral half of lower leg
| Dorsum of foot
82
How will an injury to the superficial branch of the common peroneal nerve appear?
Dorsiflexion intact
| Loss of sensation over anterolateral lower leg and foot
83
How will an injury to the deep branch of the common peroneal nerve appear?
Weakness of dorsiflexion
| Loss of sensation around 1st web space on dorsum of foot
84
What nerve is likely injured if a patient is stabbed in the antecubital fossa?
Median nerve
85
What is Gallow's traction?
Used in infants/children with femoral fractures
Fractured and healthy femur placed in skin traction and infant suspended from special frame with buttocks just off the bed for 1 week per year of age + 1 week
Start mobilizing at 6w
86
Name the complications of Gallow's traction
Vascular compromise
Occipital pressure sore
Aspiration
Compartment syndrome
87
What is Waddell's triad?
Femur fracture
Head injury
Thoracic/abdominal injury
88
When is a Thomas splint used?
For femur fractures with skin/skeletal traction
89
How do you determine the size of the Thomas splint?
Thigh circumference at groin + 4cm for ring
| True limb length + 20cm
90
How do you calculate the weight of traction with a Thomas splint?
10% of patient's body weight
| Maximal weight = 5kg (skin sloughing)
91
Name indications for skin traction
Femur fractures
Hip dislocation
Hip fracture-dislocation
92
What views do you want in a trauma series XR?
1. AP chest
2. AP pelvis
3. Lateral c spine
4. AP and lateral of all suspected bones injured
93
Name complications of bed ridden patients
1. Delirium
2. Confusion
3. Pneumonia
4. PE
5. Ileus
6. Constipation
7. Stress ulcers
8. UTI
9. Pressure sores
10. DVT
11. Muscle weakness
12. Contractures
94
How do you prevent pneumonia in bed ridden patients?
Physiotherapy
95
How do you prevent PE in bed ridden patients?
DVT prophylaxis
96
How do you prevent constipation in bed ridden patients?
High fiber diet
| Lactulose
97
How do you prevent stress ulcers in bed ridden patients?
PPI
| H2 receptor antagonists
98
How do you prevent UTI in bed ridden patients?
Silicon catheter
| Treat with antibiotics
99
How do you prevent pressure sores in bed ridden patients?
Turn 4hrly
Examine pressure points regularly
Ripple bed
100
How do you prevent DVT in bed ridden patients?
LMWH
| Pressure stockings
101
How do you prevent contractures in bed ridden patients?
Early mobilization
| Physiotherapy
102
What is the peak age of supracondylar fractures?
7yo
103
Name the mechanisms of supracondylar fractures
96% extension injuries via FOOSH
| 4% flexion injuries
104
What is the most common displacement in supracondylar fracture?
Posterior displacement
105
Name the clinical features of a supracondylar fracture
```
Pain, swelling, tenderness
S-deformity (posterior displacement)
Neurovascular injury
- radial aa
- radial, median, ulnar nn
```
106
What on XR will suggest supracondylar fracture?
Disruption of anterior humeral line
| Fat pad sign
107
What is the anterior humeral line?
Line drawn down the anterior surface of the humerus that should intersect the middle third of the capitulum
Indicates supracondylar fracture if not
108
What is the radiocapitellar line?
Line drawn through center and long axis of the radius that should go through the capitulum
Indicates radial head dislocation if not
109
Discuss the Gartland classification of supracondylar humeral fractures
Type I
- non-displaced
Type II
- anterior cortex displaced but posterior cortex still in continuity
IIa
- less severe with distal fragment angulated
IIB
- severe with distal fragment angulated and malrotated
Type III
- completely displaced fracture with preserved posterior periosteum
Type IV
- displaced with periosteal disruption, unstable in flexion and extension
110
Discuss the management of supracondylar humeral fractures
Acute
- gently splint in 30 degrees flexion to prevent movement and neurovascular injury during XR
Non-displaced = non-operative
- long arm plaster backslab in 90 degree flexion for 3w
- XR 5-7d later to ensure no displacement
Operative:
a) Displacement >50%
b) Vascular injury
c) Open fracture
- percutaneous pinning with k wires followed by limb cast with elbow flexed <90 degrees
111
Name complications specific to supracondylar humeral fracture
```
Stiffness
Brachial artery injury
Medial, radial, ulnar nn injury
Compartment syndrome
Malalignment cubitus varus
```
112
What is Dunlop traction used for?
Maintenance of reduction in paediatric supracondylar humeral fractures
113
When is Dunlop traction contraindicated?
Open fracture
| Skin defects
114
Explain the method of Dunlop traction
Skin traction placed on forearm and elevate 45 degrees over drip stand with 1.5kg weight
Broad sling around upper arm to enable traction along axis of forearm and right angles to humerus
Bed blocks required on lateral side of the bed
115
What should you do if there is no pulse in a displaced supracondylar humeral fracture?
Pink pulseless hand:
Modified Dunlop
No pulse -> Dunlop
No pulse -> orthopaedics
Cold pulseless hand
Full Dunlop and phone the vascular surgeon
116
Name the mechanisms of injury of tibial and fibular fractures
1. Twisting force causing spiral fracture of both at different levels
2. Angulatory force producing transverse/oblique fractures at same level
3. Indirect low energy injury causing spiral or long oblique fracture that may pierce the skin
4. Direct high energy injury crushes/splints the skin over the fracture
117
Name clinical features of tibial and fibular fractures
Severe swelling
Bruising
Crushing/tenting of the skin
Neurovascular injury
118
Discuss the management of tibial and fibular fractures
Closed and minimally displaced
- long leg cast 8-12w w/ functional brace after
Displaced and closed
- ORIF w/ IM nail, plate and screws or EF
Displaced and open
- AB
- I&D
- EF or IM nail
- vascularised coverage of soft tissue defects
119
Name complications of tibial and fibular fractures
```
Vascular injury
Compartment syndrome
Infection
Joint stiffness
Complex regional pain syndrome
```
120
Which vascular supply is endangered by tibial fracture?
Popliteal artery
121
Where is spinal TB most often found in the spine?
Thoracic spine
122
What is the most common site of skeletal TB?
Spine
123
Name clinical features of TB spine
```
Constitutional symptoms
- chronic illness
- malaise
- night sweats
- weight loss
Back pain
Kyphotic/gibbus deformity
Neurological deficit
Cervical = dyspnoea, dysphagia
Thoracic = pectus carinatum
```
124
What are the mechanisms of neurological deficit in TB spine?
1. Mechanical pressure on cord by abscess, granulation tissue, tubercular debris, caseous tissue
2. Mechanical instability from sublaxation/dislocation
3. Stenosis from ligamentum flavum ossification and severe kyphosis
125
What investigations should you do to diagnose TB spine?
```
Skin tests (sensitive, non-specific)
HIV status
ESR
WCC
XR
MRI
Needle biopsy
```
126
Name the features of spinal TB on XR
```
Early
- local osteoporosis of 2 adjacent vertebrae
- loss of crispness of the end plate
Late
- disk space destruction
- collapse of adjacent vertebral bodies
- severe kyphosis
- paraspinal soft tissue shadows
```
127
Give a differential diagnosis for TB spine
Malignancy
Pyogenic infection
Fungal infection
Parasitic infection (hydatid disease)
128
Discuss the treatment of TB spine
```
1. Pharmaceutical
Full drug treatment for 9-12mo
OR
Pulmonary strategy:
RIPE for 2 months then RI for 9-18 months
Resistance
- fluoroquinolone
- aminoglycoside
2. Surgical
- abscess drainage
- advanced disease
- neurological deficit that has not responded to drug therapy within 8w
```
129
Which TB drug is bacteriostatic?
Ethambutol
130
Name side effects of TB treatment to monitor for?
Hepatitis (isoniazid)
Depression (ethambutol)
Visual acuity (ethambutol)
131
What is the mnemonic for TB drug side effects?
INH (iron accumulation, neuritis, hepatitis)
Ethambutol = eyes
Rifampin = red
Pyrazinamide = hyperuricemia
132
What is the main complication in TB spine?
Pott's paraplegia
- early onset paresis
- late onset paresis
133
Name early local complications of fractures
```
Skin
- necrosis
- fracture blister
- open wound
Muscle
- compartment syndrome
Nerve
- neuropraxia
- axonotmesis
- neuronotmesis
Vessels
- arterial injury
Tendon injury
Infection
```
134
Name early systemic complications of fractures
```
Hemorrhagic shock
FES
ARDS
SIRS
MOFS
DVT
PE
Delirium tremans
Pressure sores
Tetanus
Sepsis
```
135
Name late complications of fractures
```
Delayed union
Non-union
Malunion
Avascular necrosis
Growth disturbance
Osteoarthritis
Joint stiffness
CRPS
Heterotopic ossification
Osteomyelitis
```
136
Name fractures that always require surgery
Neck of femur in young patients
Galeazzi
Monteggia
Lower limb in elderly
137
Name general indications for ORIF
```
Failure of closed reduction
Failure to maintain closed reduction
Displaced intra-articular fractures
Polytrauma
Pathological fracture
Non-union
Floating elbow/knee
```
138
Name sites of intra-articular fractures
```
Tibial plateau
Tibial plafond
Intra-articular distal radius
Radial head
Femoral intercondylar
Humeral intercondylar
```
139
Which ankle fracture does not recieve ORIF?
Non-displaced lateral malleolus without medial tenderness
140
What does medial ankle tenderness indicate?
Medial malleolus fracture
OR
Deltoid ligament injury
141
How are foot fractures generally managed?
Non-operative if non-displaced
Talus ORIF
Calcaneus ORIF
142
What is the most common malignant tumour type in a patient <10yo?
Ewing's sarcoma
143
What is the most common malignant tumour type in a patient 10-20yo?
Osteosarcoma
144
What is the most common malignant tumour type in a patient >50yo?
Metastases
145
Which sites does osteosarcoma commonly affect?
Sites of rapid growth
- distal femur
- proximal tibia
- proximal humerus
146
Name risk factors for osteosarcoma
Paget's disease
| Previous radiation
147
Name clinical features of osteosarcoma
Progressive pain
Night pain
Poorly defined swelling
Decreased ROM
148
Name XR findings in osteosarcoma
```
Variable appearance
- hazy osteolytic areas
- unusually dense osteoblastic areas
Poorly defined margins
Sunburst effect
Codman's triangle
```
149
Discuss the management of osteosarcoma
```
Multiagent chemotherapy for 8-12w
Complete resection w/ limb salvage
Neoadjuvant chemotherapy
Bone scan
CT chest
```
150
How do you see if the talus has shifted?
Spaces on all 3 sides (medial, lateral, superior) of the talar dome must be equal
151
How do we classify ankle fractures?
Denis-Weber
Type A - infrasyndesmotic
Type B - trans-syndesmotic
Type C - suprasyndesmotic
152
Discuss the management of ankle fractures
```
Acute
- reduction under conscious sedation
- below knee backslab
Surgical
- ORIF
```
153
What is a Pott's fracture?
Name for a variety of bimalleolar fractures
Tibia and fibula splay
Talus goes superior
154
What are the signs of flexor tenosynovitis?
Kanavel's signs
- flexed posturing of the involved digit
- tenderness to palpation over tenderness sheath
- marked pain with passive extension of the digit
- fusiform swelling of the digit
155
Define a dislocation
Joint surfaces are completely displaced and no longer in contact
156
Define a sublaxation
A lesser degree of displacement such that the articular surface are partially apposed
157
Define fat embolism syndrome
An inflammatory response to embolized fat globules in the circulation
158
Give the criteria for fat embolism syndrome
Gurd's criteria
```
1 major + 4 minor
Major
- petechial rash
- respiratory involvement
- cerebral involvement
Minor
- tachycardia
- pyrexia
- retinal changes
- anuria/oliguria
- thrombocytopenia
- anemia
- high ESR
- fat macroblobinemia
```
159
What are the theories of FES aetiology?
1. Mechanical obstruction in pulmonary capillaries
| 2. Free fatty acids directly affecting pneumocytes
160
Discuss the treatment of FES
Adequate splinting of long bone fractures
O2 administration
Fluids
