Hidden Hazards: Injury Risks in Sonography - SD

Introduction

Hello, I'm Carolyn Coffin.
I'm the department chair
for the diagnostic ultrasound program at Seattle University
in Seattle, Washington, and an ergonomic consultant
for sound ergonomics.
Today we're going to talk about occupational injury in
sonography, the hidden hazards of your job.

Hidden Hazards Analogy

On this picture of an aquarium, you would think
that there's just water plants in here when in fact there's
actually a hidden seahorse.
Just like in this aquarium,
there are hidden hazards where you work.
You may not realize it.
The three most prevalent ones relate to your work tasks,
your work schedule and job stress.

Workplace Stress

Workplace stress usually results from an imbalance
between the job demands on the worker
and the worker's capacity to meet those demands.
But what we don't realize is
that workplace stress impacts other health conditions
and increases our risk For musculoskeletal disorders,
there's two kinds of stress, eustress and distress.
Eustress is actually a positive form of stress,
and we see this in situations such as getting ready
for the holidays or trying to
prepare for a promotion.
These kinds of stressful events actually give us
a competitive edge and actually end up
with a more positive outcome.
Distress, however, has negative implications.
You notice on this graph that there is a relationship
between stress and performance in the workplace.
At some point, stress does have the ability to allow us
to respond to it in a positive way,
but once we meet the maximum tolerance level,
stress actually then results in our performance level
falling off, and now we have a bad response
to the stress we're experiencing in our workplace.

Work-Related Musculoskeletal Disorders

What are work-related musculoskeletal disorders?
These disorders are not the result of an acute event.
They're actually the result
of a more gradual chronic development due
to our exposure over time to injury risks.
Work-related musculoskeletal disorders are not related
to one specific task,
and the treatment of these disorders is
very difficult to predict.
Often they recur after years
or even decades after treatment.
Work-related musculoskeletal injuries differ from other
workplace injuries such as cuts, needle sticks, and slips
and falls because they cannot be attributed
to a specific work task.
In these, these other types of injuries, the results
of recovery are predictable
and these injuries are treatable.

Incidence of Injuries

The incidences of work-related musculoskeletal disorders has
changed over the past 11 years.
In 1997, a survey done in the United States showed that 81%
of sonographers were scanning in pain.
28% of the respondents reported
that their career had been affected by this disorder.
The survey was again repeated in 2008,
and the incidences of injury was 90% with
14% of those responding having had changed their job
as a result of this injury.

Reasons for Increasing Injury Rates

So why have we seen an increase in the injury rate
over the past 12 years?
Part of it is that employees are more aware of this injury
and what causes it and are more willing to report it.
They're less tolerant of working in pain
and also they have longer work hours
and higher numbers of exams to complete.
There is some factor related to job dissatisfaction,
but overall, one of the biggest factors is aging.
The median age of sonographers is 45 years of age,
and this is an increase over the past 12 years from 42 years
of age, and you can see from this graph a large percentage
of sonographers are between the ages of 40 and 60.
So what does that mean for us?
Peak muscle strength for both men
and women is reached between the ages of 25
and 35 years, so in reality, 68%
of sonographers are over 40 years
and are working beyond their years of peak muscle strength.
In addition, the increase number of exams
or the increase in our production has made a big
impact on injury rates.
You can see from this graph that from 1992 to 2005,
there's been a 57% increase in the number
of ultrasound cases performed each year by one sonographer.
However, the primary cause
for this increase in the injury rate
is the technical advances in medical imaging.
Our equipment has become computerized,
our exams are digitized,
and we have filmless image acquisition and storage.
All of these factors have led to a more frozen relationship
with our workstations
and we don't have to move to perform our work tasks.
This changing work technology started with the assembly line
that Henry Ford created for his auto workers.
They no longer had to get up
to get parts to perform their job.
Everything came to them.
The increase use in technology leads
to a decrease in the need to move to perform the work tasks,
and as I mentioned, it causes a frozen relationship
between the user and his or her equipment.

Causes and Impacts of Work-Related Musculoskeletal Disorders

Work-related musculoskeletal disorders
develop for a couple of reasons.
Excessive use frequency
of the repetitive motions necessary to perform a task.
The duration of the load on your tendons
and muscles, the level of your muscular activity
during your work tasks
and insufficient recovery time all contribute
to the development of these injuries.
42% of hospital imaging departments are understaffed,
so the impact of this injury contributes
to our staffing issues.
It also affects the quality of patient care
and impacts the financial viability of a department.
In addition, there are personal financial
and emotional strains on the sonographer.
In addition, it has an impact on your leisure activities
and on your ability to perform household duties.

Direct Costs

There are direct costs associated with this injury
and these are related to the cost of medical care
and the cost of workers' comp insurance.
The mean cost per case
of an upper extremity musculoskeletal injury
is over $8,000 versus $4,000 for all other types
of occupational injury.
The medical cost to treat a shoulder injury without surgery
for one injured sonographer is $20,000 a year.
These direct costs are increasing twice as fast
as other benefits.
One of every $3
of workers' comp costs are spent on work-related
musculoskeletal injuries.
In the United States, these injuries cost employers up
to $20 billion a year.
In lost work days, claims per injury can be as high
as $32,000 per year.

Risk Factors

The risk factors for this injury depend on three things.
They depend on the duration of exposure to the injury risk,
and in ultrasound, that's how long are we scanning
the frequency of the exposure to the risk, which is
how often or how many exams
and the intensity of the exposure.
And in ultrasound, that's
how much pressure are you using during your exam.
Other factors that increase the risk are when we perform one
type of exam all day.
The computerization of our equipment,
which again has allowed us not to mo have to move
to perform our work tasks, improper use
of ergonomic equipment, not using the features
of our workstations.
Some of our leisure activities can contribute to this risk
and some physical personal factors such as age
and body mass index.

Injury Producing Activities and Common Conditions

The injury producing activities in sonography include
overuse, awkward postures and movements, forceful movements
and improper and static body positions.
This list is a list of the conditions
of work-related musculoskeletal injuries.
In sonography, tendonitis
and teno synovitis often go together.
Teno synovitis is inflammation
of the sheath around a tendon.
Duque band syndrome is a particular type
of tendonitis of the thumb.
Carpal tunnel, cubital tunnel
and thoracic outlet syndrome are all
nerve entrapment syndromes.
Epicondylitis is inflammation of the epic condyles
of the elbow, trigger finger results from entrapment
of a tendon within the tendon sheath of the finger
and then prevents you from being
able to straighten your finger.
Often this is related to gripping the transducer.
Bursitis and rotator cuff injuries affect the shoulder
and we're seeing an increasing incidence
of spinal degeneration
among younger sonographers than we have in the past.

Specific Syndromes and Injuries

Cubital tunnel syndrome results in pressure on the ulnar
nerve caused by elbow flexion and twisting of the elbow.
This syndrome can cause pain and numbness in the fourth
and fifth fingers, often pressure on the elbow
by leaning on it, for instance, as in this example,
can damage that nerve as well.
Repeated flexion and twisting of the elbow can cause micro
tears to occur at the attachment site of the muscle tendon
to the bone of the epic condyles of the humerus.
Epicondylitis causes pain over the epic condyles weakness
of the wrist and decreased grip strength Reaching
above your head and prolonged arm abduction can cause the
muscle tendons to rub against the humeral head
causing irritation of the tendons and eventually tendonitis.
Rotator cuff injury is an injury
that is more common as we age.
Add to that the stresses of our job
and this injury is becoming more prevalent.
Rotator cuff injury can result when there's static posture
that causes compression
of the humeral head against the rotator cuff muscles.
This occurs when the arm is elevated beyond 30 degrees.
This type of elevation restricts the con circulation
to the humeral head and results in over 30 millimeters
of mercury of pressure against the muscles and tendons
and vessels in the shoulder.

Muscle Effort: Static vs Dynamic

There are two types of muscle effort. Static and dynamic.
Static muscle effort causes blood vessels
to be compressed while you're in a static posture.
Remember, your muscles act as a pump for blood.
During dynamic efforts, the results
of sustained static efforts cause insufficient blood flow
to muscles and tendons
and the ability of them to remove their waist products,
which results in acute pain and muscle fatigue.
Dynamic muscle effort allows for muscle contraction
and relaxation and acts as a pump for blood.
Blood containing waste is pumped out of the muscles
and then during muscle relaxation.
Fresh blood flows in dynamic efforts can be sustained
for much longer periods of time than static efforts
before fatigue sets in.

Risk Producing Postures

One type of risk producing posture are those when you are at
the extreme range for your extremity.
This posture requires a lot of muscle activity
to support your arm in this position.
Awkward postures
that are not at the extreme range can also cause injury.
They can create a mechanical load on the body or the joint
and they change the body's alignment.
Some possible effects when you're at your extreme range
for your joint is stress on the joint reduction
or occlusion of blood flow
and high muscle force necessary to sustain that posture.
An example of this is forearm pronation.
As you see in this example,
the sonographers arm in wrist are pronated in order
to perform this exam.
When you change the body's alignment,
the possible effects on the body include increasing stress
on the tendons and muscles,
and this causes injury to surrounding tendons.
You obstruct normal function of the joint
and you can reduce blood flow.
An example of this particular posture is wrist flexion.
You will notice in this picture the sonographer scanning has
a great deal of wrist flexion reaching in
to scan this patient wrist flexion reduces the carpal tunnel
and increases pressure on the median nerve injury
to the median nerve results in sensory and motor symptoms.
When the wrist is flexed,
the pressure against the median nerve can be
60 millimeters of mercury.
When the wrist is extended,
that pressure can be 120 millimeters of mercury.
You'll notice in these two pictures, the wrist in flexion
on the top and on the bottom,
and in this picture the extension of the wrist.

Arm Abduction and Excessive Reaches

Another awkward posture places physical loads on the body.
The effects of this are that you increase the force caused
by non neutral postures.
You increase muscle firing to maintain the position
and this causes a high risk for musculoskeletal disorder.
One example of this particular posture is arm abduction.
Unfortunately, arm abduction is a common posture in
sonography, and you'll notice in this picture the
stenographer's arm is almost 90 degrees from her body.
Not only is this stenographer's arm abducted,
but it's actually behind her shoulder.
You'll notice in this diagram the time it takes
to reach muscle fatigue.
When you have different degrees of arm abduction
at 30 degrees of arm abduction, you can maintain
that posture for about 60 minutes,
but at 90 degrees of arm abduction, notice
that you can only maintain that posture for about 10 minutes
before muscle fatigue sets in.
You'll notice that there's a direct correlation
between muscle strength and shoulder abduction,
and as that angle of abduction increases,
muscle strength falls off.
Excessive reaches also an awkward posture
that creates a load on the shoulder.
It reduces your muscle endurance and causes fatigue
and injury based on these times
and these distances of reach
at 30 centimeters from your body.
You can maintain that reach for about 30 minutes,
but notice if it's 50 centimeters, it's only seven minutes.
Reducing reach can reduce muscle firing by up
to 65% in the upper trapezius muscle.
Notice the amount of reach in these two pictures.
In this top picture, the stenographer's reach is actually
with her non scanning arm, so you also have to be aware of
what you're doing when you're reaching for the control panel
of the ultrasound system.
In this bottom picture, the amount of reach is related
to the sonographer reaching forward to access the patient.
Increasing the horizontal distance of your reach
decreases the time for the onset of fatigue.
The work of your shoulder will increase
as your hand moves farther from your body.
This requires more muscle support
and causes a quicker onset
of muscle fatigue in your shoulder and arm.
By supporting your arm with various different devices,
muscle firing can be reduced.
This will increase your endurance time even though you're
actually reaching a little farther than 30 centimeters.

Neck and Trunk Postures

Another posture to avoid is neck flexion and extension.
In these three examples, the sonographers are in either
HyperFlex positions or hyperextended positions.
These positions are generally the result of
where you position the monitor
or yourself with regard to the ultrasound system.
To prevent looking down, you should either raise the monitor
or sit down To prevent too much neck
extension, you should either stand up
or lower the monitor.
Neck twist is another issue for sonographers.
In this particular example,
the sonographer is actually standing backwards
to the ultrasound system causing her
to twist her neck almost to as far as it will go.
This is another example of neck twist
where the sonographer is actually trying
to determine the lie of the fetus.
Trunk twist is also an awkward posture in sonography.
In this top image, the sonographer is reaching across
and twisting her trunk to access the patient.
In this bottom picture, the sonographer has set up the
ultrasound system at the foot
of the bed at 90 degrees from her causing her
to twist not only her neck but herb trunk.
Another example of twisting, including bending
to reach the patient In this particular image on top,
the sonographer could move the patient closer,
which would prevent having to bend over
and in this bottom picture,
the sonographer could move the patient closer and stand up.
Straighter stands closer to the ultrasound system
and prevent both twisting and bending.

Excess Force and Obesity

Other risks include excess force.
When we push against the patient
or holding the transducer,
increased force is often required as a result
of the increasing obesity in our population.
Some of the other risk factors associated
with obesity are diabetes, increased risk for heart disease
and decreased blood flow to muscles and joints.
Therefore, obesity is not just a risk for us scanning,
but it's also a risk to the workers'.
Health. Obese workers have increased work limitations
and decreased productivity.
Obesity is actually defined as a body mass index
of 30 or higher.
We've seen an increase in this prevalence
of obesity over the past 20 years.
These next few slides will demonstrate the trend in obesity
among United States adults.
Starting in 1985.
You'll notice that there's not much prevalence beyond 14%
and not many states that had that prevalence of obesity,
but as we go through the slides, you can see
that there's an increase in the incidence of obesity
among all the states of the United States, 1995,
there's a cat, a new category of 15 to 19% incidents,
and when you get to 2000, you can see that there's a number
of states where the incidence
of obesity is greater than 20%.
In 2004, there's a number of states
where the incidence is greater than 25%.

Gripping the Transducer

Other risk factors include gripping the transducer,
whether it's too narrow or too wide.
A narrow transducer causes a pinch grip,
which causes the muscles in the hand and fingers.
To become fatigued too wide
of a transducer requires too much
stretch of the hand muscles.
We have an increased risk
for injury if we are gripping the transducer greater than
two hours per day with either 10 pounds of force
or pinching with greater than four pounds of force.

Treatment and Prevention

Treatment for work-related musculoskeletal disorders is poor
workers tend to return to the same risk factors
that cause the injury to start with
and they become re-injured.
Therefore, it's important to prevent these injuries.
The keys to prevention are both ergonomics and education.
There are a couple of ed of ergonomic models.
One of them is fitting the person to the job,
and this is basically based on physical conditioning,
physical training, onsite wellness,
but it is not a substitute for good ergonomics.
Good ergonomic models are
where the job is fit to the person.
This requires changing the work design changing workstations
and the changes are intended to reduce injury risks
and in some cases eliminate them.
The definition of ergonomics basically is that it removes,
removes barriers to quality production
and to safe human performance by fitting the products, tasks
and the work environment to the worker.
The core concepts for ergonomics are
to work at the proper height,
maintain neutral body position, reduce FA fatigue factors,
maintain the appropriate reach zones,
and reduce excess force.
In ultrasound, these injuries are not caused by
what we do but how we do it.

Maintaining Neutral Postures and Adjustments

There are a number of changes you can make
in your work postures.
The most important thing is
to always maintain neutral postures.
When you can, you want to make sure
that your forearm is parallel or slightly below parallel.
You wanna make sure when your seated
that your thighs are parallel
or your knees are slightly below your hips.
You wanna make sure that your neck
is in a neutral position looking straight ahead.
Neutral risk positions can be obtained as long
as you avoid too much ulnar deviation or radial deviation.
Also, you only have about a 15 degree angle of flexion
or extension before your wrist is out of a neutral posture.
You would like to avoid disposition
and try to maintain disposition that may require changing
how you hold the transducer.
In some instances, in order to reduce arm abduction
and trunk bending, make sure
that you move the patient closer.
There's too much distance between the sonographer
and her patient causing her arm
to be abducted to 90 degrees.
By bringing the patient closer,
the arm abduction has been reduced.
In this case, you also wanna make sure that you work within
what is known as your reach zone,
and this is a zone that you can reach
with your arms about 30 degrees from your body
and only about a 30 centimeter reach.
Occasionally, you'll have to go beyond that zone,
but you should always try to come back into the reach
zone whenever possible.
It's important to work at the proper height too low,
and your arm is abducted too high and you're bending over.
There are ways that you can change your position
or that of the patient to avoid these extreme postures.
In this case, the stenographer is seated
with her arm supported on the back of the chair
and has no reach to her patient
To avoid bending and twisting.
You just simply re reposition yourself and the equipment.
The sonographer is bent over and reaching.
She could have had her patient roll up on her side.
She would've been able to straighten her posture
and reach the patient more comfortably
for an endo vaginal exam.
This sonographer has stepped in between the stirs
and can now keep her arm close to her body
and avoid reaching.
Neutral. Neck positions can be obtained
by raising the monitor or changing your position.
The sonographer could have had a seat
and she would've been viewing the monitor
at a more neutral position.

Importance of Seating and Body Position

One thing we tend to forget is how important seating is.
It's important to have a height adjustable chair
and one that promotes the normal lordotic
curve of our spine.
When we are seated, we wanna avoid
a slumped kyphotic curve.
This is an example of the effects
of body position on your spine.
If you're lying down, you're putting about 56 pounds
of compression force on your spine.
When you stand up in a neutral position,
you've almost doubled that force to 112 pounds.
If you're sitting without any support, that force goes up
to 157 pounds, and if you're sitting
and bending forward by about 40 degrees,
you're now putting 220 pounds of pressure on your spine.

Utilizing Ergonomic Features

It is very important that you take advantage
of the ergonomic features on your ultrasound systems.
Make an effort to learn those features and then use them.
Once you get used to repositioning the equipment,
it becomes habit and it becomes much easier.
In this case, if the sonographer had been able
to raise the monitor, she would've had a more neutral body
position and a more neutral neck position.
Utilize the newest technology on your systems so
that you can more comfortably perform your work tasks.
Always reposition the monitor when you change positions
and avoid working from behind the monitor, as in this case,
it's also important to utilize the ergonomic features
of your ancillary exam room equipment.
If your chair adjusts in height, take advantage of
that adjustment and make sure
that you're positioned comfortably
and can see the monitor without neck extension or flexion.
If you have an adjustable exam table, make sure to raise
and lower that as necessary so that you
minimize your arm abduction.
And don't forget your workday includes the computer
workstation or the PAX workstation.
That equipment should also be adjustable,
and you should position the monitor of the computer
and the keyboard so that you have avoided awkward,
uncomfortable postures.

Conclusion

But overall, one of the most important things
to remember is to move.
When are you not moving at all?
That's right when you're dead, So it's important
to take the time when you go into your exam
room to make it right.
Make sure that you set up all the equipment so
that you minimize your risk for injury,
and that means minimizing your reach,
minimizing arm abduction, and keeping your neck
and body in neutral positions.
Once you get used to setting up all the equipment,
it will come fast and easy to you.
We have to start being creative in how we do our work.
We can't continue to use the same postures
that cause these injuries to start with.
As Albert Einstein said, the problems
that exist in the world today cannot be solved by the level
of thinking that created them.
Thank you.