week 9

Question 1

time course for non specific LBP – acute vs subacute vs chronic

Answer 1

Acute: < 6 weeks Subacute: 6-12 weeks Chronic: > 12 weeks

Question 2

why is non specific LBP a term

Answer 2

no pathoanatomical cause to the painw

Question 3

what % of LBP in primary care settings is non specific

Answer 3

90%

Question 4

risk factors to non specific LBP

Answer 4

Physical Factors:
Prolonged standing, walking Lifting heavy weights
Unhealthy Lifestyle: Smoking
Obesity
Psychological Factors: Depression
Job dissatisfaction
Prior episode of low back pain

Question 5

things to rule out via history to diagnose non specific LBP

Answer 5

i.e. red flags like osteoporosis, fractures, cauda equina, neoplasia (cancer), infection, aortic aneurysm

make sure no sensory loss, parenthesis, motor deficits, fever, weight loss, systemic symptoms, bladder and bowel problems, smoking, dyslipidemia, malignancy

neurological exmas
straight leg raise…
check abdominal pain (aortic aneurysm)

Question 6

LRs of red flags

Answer 6

history of cancer has high LR for spinal malignancy

spinal fracture; prolonged corticosteroid use has LR+ of 48.5 and 3 positive finds of Henschke index (female, >70yrs old, severe trauma, prolonged corticosteroids) has LR+ of 906

Question 7

C-reactive protein

Answer 7

Acute phase protein which rises in response to inflammation

Non-specific, but can be used together with signs and symptoms and other tests to evaluate for acute or chronic inflammation

Acute=
Any infection, especially bacterial
Acute flares or onset of inflammatory/immune-mediated disease

Chronic=
Chronic infections
Chronic inflammatory/immune-mediated conditions

Question 8

erythrocyte sedimentation rate

Answer 8

Measurement of the rate at which RBCs settle in saline solution or plasma over a specified time period

Because inflammatory, neoplastic, infectious and necrotic diseases increase the protein content of plasma, RBCs tend to stack upon one another, increasing their weight, causing them to descend faster

Non specific test used to help detect acute and chronic inflammation

Does not change as rapidly as CRP

If elevated usually a result of globulins or fibrinogens
- Polymyalgia rheumatica
-Moderately elevated
Inflammation, anemia, infection, pregnancy
-Very high
Severe infection

Question 9

imaging for fracture

Answer 9

plain radiograph

Question 10

imaging for infection, malignancy, neurologic, cauda qeuina

Answer 10

MRI

Question 11

how long to diagnose non specific LBP

Answer 11

> 6weeks with no identifiable cause is NSLBP.

However, red flags must be ruled out in the
acute presentation and if there is no progress with conservative management

Question 12

contraindications, advantages and disadvantages of x ray imaging

Answer 12

Contraindications:
pregnancy (relative)

Advantages:
inexpensive, non-invasive, readily available, portable, reproducible, fast, easily read

Disadvantages:
radiation exposure (minimal), generally poor at distinguishing soft tissues

Question 13

x ray imaging mechanism

Answer 13

Form a short wavelength electromagnetic energy
Photons traverse matter, they can be absorbed (a process known as “attenuation”) and/or scattered
The density of a structure determines its ability to attenuate or “weaken” the x-ray beam
air < fat < water < bone < metal

Question 14

what to use x ray- plain films for

Answer 14

Structures that have high attenuation (e.g. bone) appear white on the resulting images

Question 15

x ray plain films vs computed tomography

Answer 15

plain films= 2Dimensional

computed tomogrpahy- anatomic structures are reconstructed

Question 16

use of x ray- computed tomogrpahy

Answer 16

e.g. CT chest can be viewed using “lung”, “soft tissue”, and “bone” settings)

Question 17

units for x ray- computed tomography

Answer 17

hounsfiled units

Question 18

c ray- computed tomography

Answer 18

X-ray beam opposite a detector moves in a continuous 360o arc as patient is advanced through the scanner
Anatomical structures are then reconstructed

Question 19

x ray= computed tomography AKA

Answer 19

CT scan!!

Question 20

advantages of CT sc an

Answer 20

biopsies and non invasive and soft tisssue

Delineates soft tissues, excellent at delineating bones and
identifying lung/liver masses May be used to guide biopsies
Spiral/helical multidetector CT has fast data acquisition and allows 3D reconstruction
CTA non-invasive compared to conventional angiography for visualization of vasculature

Question 21

disadvantages of CT scan

Answer 21

High radiation exposure
Soft tissue characterization is inferior to that seen on MRI Requirement for contrast in some studies (e.g. IV, oral, rectal), Patient anxiety going through scanner
Increased cost and decreased availability compared to plain film Requirement for expert interpretation of images

Question 22

MRI mechanism

Answer 22

Imaging technique that does not use ionizing radiation and can produce images in virtually any plane

Patient is placed in a magnetic field generated by electric current; protons, typically from water

Molecules, align themselves along the plane of magnetization due to their intrinsic polarity. A pulsed radiofrequency beam is subsequently turned on and deflects all the protons off their aligned axes. When the radiofrequency beam is turned off, the protons return to their pre-excitation axis, giving off the energy they absorbed. This energy is measured with a detector and interpreted by software to generate MR images

Question 23

what is an MRI signal intensity dependent on

Answer 23

1. hydrogen desnity
2. magnetic relaxation times (T1 and T2)

Question 24

what tissues create better signals on MRI

Answer 24

ones with high hydrogen density (i.e. H20)

ones with low hydrogen density i.e. cortical bone and lung are low signal

Question 25

T1 weighted vs T2 weighted MRI use

Answer 25

both body soft tissues
t1 if for anatomic scan
but tw is for pathologic scan (edemaous areas)

Question 26

what is diffusion weighted MRI best for

Answer 26

neuroradiology- ischemic stroke, infarction

Question 27

what is the gold standard for bone mineral density

Answer 27

DEXA scane

Question 28

T scores of DEXA scan for osteopenia and osteoporosis

Answer 28

osteopenia: –2.5< T-score <–1
osteoporosis: T-score ≤-2.5

Question 29

what 2 standardized questionnaires for severity of pain and disability of LBP

Answer 29

Oswestry Disability Index (ODI)
Örebro Musculoskeletal Pain Screening Questionnaire (OMPQ)

Question 30

3 pain trajectories of LBP

Answer 30

Recovery trajectory that Improves rapidly or gradually to a state of no to little pain

Ongoing trajectory where the patient has moderate or fluctuating pain

Persistent trajectory in which the patient perceives constant and sever pain

Question 31

Oswestry Disability Index (ODI) measures??

Answer 31

severity of disability

Question 32

Örebro Musculoskeletal Pain Screening Questionnaire (OMPQ) measures??

Answer 32

is a ‘yellow flag’ screening tool that predicts long-term disability and failure to return to work when completed four to 12 weeks following a soft tissue injury

Question 33

Örebro Musculoskeletal Pain Screening Questionnaire (OMPQ) scoring resylts

Answer 33

< 105 = low risk
105-130 = moderate risk
> 130 = high risk

Question 34

poor outcomes of LBP associated with

and what is it NOT associated with

and what has inconsistent evidence

and what has insufficient evidence

Answer 34

emotional distress, depression, recovery expectations, pain catstrophism

lower level of education

femalee gender, positive sciatic or nerve root involvement, prior back pain episodes, fear avoidance beliefs

low work social support, low social activity, age

Question 35

3 categories of pain catastrophizing scale

Answer 35

rumination
magniification
helplessness

Question 36

Fear Avoidance Beliefs Questionnaire

Answer 36

The FABQ measures patient’s fear of pain and consequent avoidance of physical activity (PA) because of their fear.

Question 37

how is non specific low back pain diagnosed

Answer 37

Nonspecific low back pain is diagnosed on the basis of the exclusion of specific causes, usually by means of history taking and physical examination.

Rule out red flags and consider yellow flags

Question 38

when to consider problems beyond the spine

Answer 38

Systemically unwell

Nonmechanical pain (i.e., pain that is unrelated to movement)

Hip joint signs (consider hip joint disease)

Abdominal pulsations (consider abdominal aortic aneurysm)

Gynecologic, renal/urinary tract, gastrointestinal signs and symptoms (e.g., abdominal tenderness, hematuria) (consider visceral origin)

Atherosclerotic risk factors, claudication (consider vascular origin)