Ergonomics Flashcards
ergonomics
the science of fitting hobs to the people who work them
goals of ergonomics (4)
❖Prevent work-related musculoskeletal disorders (MSDs)
❖Increase safety and productivity
❖Enhance performance by eliminating unnecessary effort
❖Improve the standard of care to the patient
In a University of CA-SF questionnaire, responses indicated that –% of the dental students from all four years experienced neck, shoulder and/or back pain. More than –% reported pain by their 3rd year.
46-71%
70%
when you are slouched over, why are you not able to fully breath out?
your lungs and internal organs are being compressed
musculoskeletal disorders (MSD)
include a group of conditions that involve nerves, tendons, muscles, and supporting structures such as intervertebral discs
contributing factors for work related MSDs include routine exposure to (4)
forceful hand exertions
repetitive movements
fixed or awkward postures
vibrating tools
what is the main cause of MSD in dentistry?
cumulative trauma disorders (CTDs) are theorized to be the primary cause of disability among dentists and best describes how injuries develop in dentistry
in dentistry cumulative trauma disorders begin as
microtrauma
microscopic damage that occurs to certain parts of your MS system on a daily basis
your body is constantly repairing this damage when you’re at rest
microtrauma occurs on the
cellular level, with the damage accumulative
the rate of damage to your body accumulates faster than the repair rate
do you often feel any discomfort before enough tissue damage occurs to create pain and muscle dysfunction?
no
warning signs (6)
Decreased strength (ex: instrument gripping)
Decreased range of motion (ex: turning head)
Pain or burning sensations
Numbness or tingling
Shooting or stabbing pain (usually into an arm or leg)
Swelling or inflammation
chronic low back pain (2)
often caused by a poor seated posture and weak stabilizing trunk muscles.
tension neck syndrome
common result of a forward head posture
trapezius myalgia
pain, tenderness from sustained contraction in upper trapezius muscle. Often from chronic elevation of the shoulders
rotor cuff impingement
houlder pain from over reaching, and a sustained arm elevation
carpal tunnel sundorme
medial nerve compression in the wrist from a flexed wrist posture, a forceful grip and/or gripping instruments with small diameters.
SKIPPED
dental ergonomic stressors (7)
- Sustained/awkward postures
- Repetitive tasks
- Forceful hand exertions
- Vibrating operational devices
- Time pressure from a fixed schedule
- Coping with patient anxieties
- Precision required with work
dental ergonomic equipment (4)
operator stools
patient chairs
magnification/loupes
lighting systems
3 Ps to fitness in the operatory
posture
positioning
periodic stretching
posture: maintain a
neutral position
posture (7)
❖Head at 0-20 tilt-ears over shoulders❖Shoulders over hips❖Elbows relaxed at sides❖Forearms parallel to the floor or slightly upward❖Slight curve in lower back/lordosis❖Hip angle >90-ideally 105-125*❖Feet flat on floor in tripod position
neutral seated position (5)
❖Forearms parallel to the floor ❖Weight evenly balanced ❖Hips higher than knees-110 degrees ❖Seat height positioned low enough so that you are able to rest the heels of your feet on the floor ❖Have a tripod effect-legs and torso
neutral neck position (2)
❖Head tilt of 0°to 15°.
❖The line from eyes to the treatment area should be as near to vertical as possible.
in neutral neck position, avoid (2)
head tipped too far forward
head tilted to one side
The head weighs 8-10 pounds, and for every one inch the head tilts forward, the load on neck and muscles —. Studies have shown that the greater the forward head position, the more likely people are to experience neck or shoulder pain or chronic tension headaches.
doubles
neutral shoulder position (2)
shoulders in a horizontal line
weight evenly balanced when seated
in neutral shoulder position, avoid (3)
shoulders lifted up toward ears
shoulders hunched forward
sitting with weight on one hip
neutral back position (2)
leaning forward slightly from the waist or hips
trunk flexion of 0-20 degrees
in neutral back position, avoid
over flexion of the spine (curved back)
neutral upper arm position (2)
upper arms hand parallel to the long axis of torso
elbows at waist level held slightly away from the body
in neutral upper arm position, avoid (2)
greater than 20 degrees of elbow abduction away from the body
elbows held above waist level
neutral forearm position (2)
parallel to floor
raised or lowered, if necessary, but pivoting at the elbow joint
in neutral forearm position, avoid
angle between the forearm nd upper arm of less than 60 degrees
establishing neutral position in relation to the patient (3)
- Adjust the height of the clinician chair to establish a hip angle of 110°.
- Lower the patient chair until the patient’s mouth is at the level of clinician’s heart.
- Elbow angle should be at 90°when clinician’s fingers are touching the teeth in the treatment area.
patient positioning to maintain neutral position (6)
Recline the patient: supine for maxillary, semi-supine for mandibular
❖Adjust headrest
❖Adjust chair height to maintain neutral position
❖Ask patient to move head as needed
❖Equipment placement within easy reach
❖Light position to avoid shadowing
rule of thumb (2)
when working on the mandibular, position the mandible ..
when working on the maxillary, position the maxilla ..
mandible parallel to the floor
maxilla perpendicular to the floor