552 Exam 1: Epidemiology - Risk Factors

Front 1

what is the prevalence of LBP

Back 1

17% (number of people in a given population that will have LBP)

Front 2

what is the peak prevelance of LBP

Back 2

40-60 year old age group

Front 3

What is the incidence of LBP

Back 3

between 60-90% of the total population will suffer back pain at one time in their life (number of people without back pain who will develop back pain over a given period of time)

Front 4

back related problems represent what percent of sick days

Back 4

10%

Front 5

in the US, how many work days are lost per year due to back pain

Back 5

93 million

Front 6

what percent of individuals will have a period of back pain compensation

Back 6

30-40%

Front 7

what percent of the working population is compensated for back injuries each year

Back 7

2% (as much as 20-30% of employees in some industries)

Front 8

in 1990, what was the direct and indirect cost of LBP

Back 8

$60 billion

Front 9

in 1990, how many back surgeries were performed in the US

Back 9

250,000

Front 10

in 1990, worker's compensation total cost in the US was

Back 10

$50 billion, 30 billions of which were for worker's with low back pain

Front 11

what defines an injury as work related

Back 11

it requires reporting a mechanism of injury

Front 12

what is the most often reported mecahnism of work related injury

Back 12

lifting (accounting for nearly 50%)

Front 13

what is the second most cited mechanism of work related injuries

Back 13

slipping and falling

Front 14

what type of activity is more commonly cited as causing an injury.... pushing or pulling?

Back 14

pulling is cited more often than pushing

Front 15

what is the difference in mechanism of injury between work-related injuries and non work-related injuries

Back 15

in work related, almost all injuries are attributed to a single event (due to obligation of citing a specific event), whereas in a non work-related injury only 50% are related to a single event

Front 16

non work-related injuries are usually related to what type of mechanism of injury

Back 16

cumulative trauma disorders

Front 17

what are the strongly positive risk factors for LBP

Back 17

1) smoking
2) major scoliosis
3) occupational factors

Front 18

what are the moderately positive risk factors for low back pain

Back 18

1) psychsocial problems
2) lack of fitness
3) repeated loading of back
4) genetics
5) age

Front 19

what are the somewhat positive risk factors associated with low back pain

Back 19

1) poor health
2) drug abuse
3) headaches

Front 20

what is the mechanism by which smoking is deemed a positive risk factor for LBP

Back 20

chronic cough --> forward bend --> increase intradiscal pressure --> decreased mineral content --> microfractures of vertebral body --> decreased vertebral body blood flow --> decreased nutrition of disc
MAIN POINT: metabolic structure and smoking causes decreased blood supply

Front 21

15 minutes of smoking results in......

Back 21

50% reduction of oxygen delivery to tissues

Front 22

what occupation has the highest prevalence of back problems and why

Back 22

truck drivers --> sitting increases pressure on disc and back

Front 23

trunk drivers have _____ greater frequency of disc herniation

Back 23

5X greater frequency

Front 24

what occupation has the second highest prevalence of back problems

Back 24

material handlers or anyone who has to lift people

Front 25

what are the tasks with a high risk factor for low back pain

Back 25

1) heavy physical work
2) static work posture
3) frequent bending and twisting
4) lifting, pushing and pulling
5) repetitve work
6) exposure to whole body vibration
7) psychological and psychosocial factors

Front 26

what are the two most emphasized tasks that are risk factors for low back pain

Back 26

1) heavy physical work
2) static work posture
* its the extremes that people don't tolerate very well in terms of back pain

Front 27

why is physical fitness a risk factor for back pain

Back 27

evidence shows that overall physical fitness and conditioning hae preventive effect on back pain either because individuals are stronger or beecause better nutrition to the disc (less static loading)

Front 28

what role does genetics play as a risk factor for LBP

Back 28

stong familial predisposition to low back pain... 35% of patients with back pain have at least 1 family member with similar condition compared to only 10% with asymptomatic backs

Front 29

explain the genetic and environmental connection as a risk factor for LBP

Back 29

genetics may contribute to wakness of collagen fiber... but, family members may have similar socioeconomic situation

Front 30

explain the role of age and LBP

Back 30

prevalence increased from 20-40 then peaks and remains stable between 40 and 60 then finally decreases after 60 (especially in men)

Front 31

why does it make sense for the peak prevalence of back pain to be between 40 and 60

Back 31

accumulation of trauma over 20-40 years now starts to appear.... also nucleus propulsus has decreased so much in water content that it is getting more cartilaginous

Front 32

why does prevalence of back pain decrease after 60

Back 32

1) retirement age (no more heavy manual labor)
2) lesser chance of disc herniation because less distance (disc losing water content)

Front 33

what are the questionable risk factors associated with LBP

Back 33

1) obesity
2) height
3) education
4) economics
5) trunk strength

Front 34

what are the factors that are explicitely listed as NOT being a risk factor for LBP

Back 34

1) gender
2) posture
3) body build
4) hyperlordosis
5) most scoliosis
6) leg length

Front 35

what is the key concept to keep in mind when discussing the factors that are "not a risk factor for LBP"

Back 35

they aren't risk factors for the population as a group, but they should definately be components considered in individuals with back pain

Front 36

what is the role of gender in back pain

Back 36

- no real difference
- the incidence for women is only 4% higher than men
- surgeries for disc herniation are performed twice as often in males than in females

Front 37

explain the relationship between height, obeisty and trunk strength to back pain

Back 37

some studies found them related, while others didn't
1) disc herniation is 2x more frequent in males over 6 feet tall and 3x greater in females over 5 foot 6.5 inches tall

2) study reports that individuals in the top 20% weight category have 1.7x higher incidence of back pain than subjects in the lowest 20% of weight category

Front 38

when do about 50% of women have low back pain during their pregnancy (and why)

Back 38

during late pregnancy (relaxin released in late trimester causes looseness in ligamentous structures)

Front 39

among the 50% of women who complain of LBP during pregnancy, what are the common issues

Back 39

1) 50% complain of sciatica
2) 12% have severe enough pain to reduce their activity level
3) those with more pain often have more SI joint problems

Front 40

what increases the risk for low back pain during pregnancy

Back 40

1) 2nd or more pregnancies
2) 30 or older

Front 41

Almost all back injuries are the results of:

Back 41

1) poor posture
2) poor body mechanics
3) faulty living and working habits
4) general decline of physical fitness

Front 42

who has the ultimate responsibility of the back

Back 42

the patient... ("the patient is ultimately responsible for maintaining a healthy back)

Front 43

what is the most common example of "poor body mechanics" resulting in back injury

Back 43

not moving their feet while moving objects --> causes rotational stress on the back

Front 44

someone who complains of pain while brushing their teeth often have what injury

Back 44

disc herniation.... they usually don't realize that they are bending over while brushing their teeth