ERGONOMICS IN
DENTISTRY
GUIDED BY:
DR.MAHMOOD MOOTHEDATH
DR.ASEELA AHMED
SUBMITTED BY
THRIPTHI RAJ P K
CONTENTS
*INTRODUCTION
*PRINCIPLES OF ERGONOMICS
*ERGONOMICS IN DENTAL OFFICE
*WHAT IS A MSD?
*SIGNS AND SYMPTOMS OF MSD
*RISK FACTORS FOR MSDs
* OFF JOB ACTIVITIES THAT CONTRIBUTE TO MSDs
*ERGONOMIST’S PERSPECTIVE OF DENTAL HYGIENE
WORKPLACE
*FACTORS LEADING TO RSIs
*RSIs
*MUSCLE STRENGTHENING EXCERCISES
*EYE TO FUTURE
*CONCLUSION
INTRODUCTION
*ERGONOMICS(from the greek ergon,meaning
‘’work’’,nomos meaning ‘’law’’)deals with adaptation
of the work environment to the human body.
*The goal of ergonomics is to help people stay healthy
while performing their work more effectively.
*This can be done by changing workplace
design,modifying instruments,strengthening
muscles,taking breaks,using certain products and
providing proper training.
PRINCIPLE OF ERGONOMICS
*Ergonomics designs the work area &the task
around the human body, rather than requiring the
human to adapt to poorly designed equipment and
working environment.
ERGONOMICS IN DENTAL OFFICE
The members of the dental team most
frequently perform their work in a seated position
& often use excessive motions and have unbalanced
postures.Many dental professionals experience pain
associated with MSDs.
Prior to 1985,low back pain was the most
commonly reported MSD or RSI for dentists.Since
then there has been a rise in MSDs from extended
work days,awkward postures,prolonged standing or
unsupported sitting,poorly designed
workstations,improper work habits &instuments
that are difficult to manipulate.
WHAT IS AN MSD?
*A MSD is an injury of the muscles, nerves, tendons,
ligaments, joints, cartilage, blood vessels or spinal
discs.
*These disorders can occur from a single incident,such
as lifting a heavy weight or can develop gradually
from repeated stress on a part of the body.
*MSDs can affect any part of the body,but most
commonly occur in the back, neck, shoulder, elbow &
wrist.
SIGNS OF MSDs
•Decreased range of
motion
•Loss of normal
sensation
•Decreased grip
strength
•Loss of normal
movement
•Loss of cordination
SYMPTOMS OF MSDs
•Excessive fatigue in
the shoulders&neck
•Tingling,burning or
other pain in arms
•Weak grip,cramping
of hands
•Numbness in fingers
&hands
•Clumsiness&dropping
of objects
•Hypersensitivity in
hands &fingers
RISK FACTORS FOR MSDs
• Repitition
• Forceful exertions
• Awkward postures
• Contact stress
• Vibration
• Poorly designed
equipment /workstation
• Improper work habits
• Genetics
• Medical conditions
• Poor fitness level
•Physical/mental stress
•Lack of rest/recovery
•Poor nutrition
•Environmental factors
•Poor lighting
POSTURE
Posture affects the ability of the dentist to reach,hold
& use equipment.Most dentists are seated while
working on patients.Although sitting is generally less
fatiguing than standing,any position will eventually
become fatiguing over time.This may lead to low back
pain.
NEUTRAL POSITION
*Sit upright with your weight evenly distributed
*Feet flat on the floor
*Back pressed against back of the chair for lumbar
support
The properly aligned spine resembles a gentle
‘S’.When the spine is properly aligned,the
ears,shoulders,hips are in straight vertical alignment
providing balance,support&equal distribution of
weight through out the spine.
DEVIATIONS & PROBLEMS
Deviations from neutral position such as leaning
forward,twisting,over bending back&reaching cause
strains&sprains.strains result from exteme stretching
of muscles or ligaments.Sprains usually involve a
sudden twist or wrenching of a joint with stretching
or tearing of ligaments.Shoulder problems can be
caused by repeatedly reaching behind the body for
instruments or supplies.
REACHING MOVEMENTS
Keep frequently used items such as air water syringe,
handpiece, saliva ejector &high volume oral evacuator
within a comfortable distance.
Adjust the instrument tray &equipment so that items
are within normal horizontal reach.
Keep the operatory light within a safe maximum
vertical reach,the reach created by the vertical sweep
of your forearm.
Other supplies used less frequently should be placed
within maximum horizontal reach, the reach created
when your upper arm is fully extended.
Reaches should be to the front only.Reaching behind
your back &lifting can cause shoulder injury. When
turning is necessary,rotate the chair rather than
twisting your body.
IMPORTANCE OF POSTURE
Improper workstation set up
Force dentist to assume harmful postures
*Pressure on nerves &blood vessels
*Strain on muscles
*Decrease circulation
*Wear &tear on joint structures
SOME IMPROPER POSTURES THAT
DENTISTS TAKE
*Working with neck in flexion/tilted to one side
*Shoulders elevated
*Side bending to left or right
*Excessive twisting
*Forward bending
*Shoulders flexed&abducted
*Elbows flexed >90degree
*Wrists flexed/deviated in grasping
*Position maintained for 40+minutes per patient
TIPS FOR WORKING WITH GOOD
POSTURE
1) Always try to maintain an erect posture
- Position your chair close to the patient.
- keep feet flat on the floor
2) Use an adjustable chair with lumbar, thoracic
support.
3) Work close to your body
-position your chair close to patient &tray close to
you.
-think of 90degree rule.
4)Minimize excessive wrist movements
-try to keep them in neutral position
5)Avoid excessive finger movements
-retrian yourself to use shoulders&arms to position
your hands.
6)Alternate work positions between sitting, standing &
side of the patient
-allows certain muscles to relax while shifting the
stress onto other muscles&increasing the circulation
7)Adjust the height of your chair&the patient’s chair to
a comfortable level
-too high patient’s chair
elevation of shoulder
neck problems
-too low patient’s chair
flex your neck down
neck problems
8)Check the placement of adjustable light
-position the light so you don’t have to strain your
neck to see patients mouth
9)Check the temperature in the room
-too cold work place
decrease blood flow to
extremities
ERGONOMIC CHAIR SIDE TIPS
*Use muscles to remain balanced for ease of
movement
*Avoid prolonged awkward positions
*Do not remain in one position for an extended time
*Do not constantly lean forward or to the side
*Remain in good physical condition
*Take break to stretch the neck,shoulders&hands
*Avoid repetative,forceful movements
*Rearrange items in the operatory for easy use
REPETITION & FORCE
*Repetitive motion,overflexion &overextension of
the wrist
increase risk for cumulative trauma
disorders(CTDs).
*To help prevent CTDs take periodic breaks&when
scheduling patients,alternate difficult
procedures with less stressful procedures.
OFF JOB ACTIVITIES THAT
CONTRIBUTE TO MSDs
*Home computer use
*Repititive activities using the fingers
*Sports activities
*Prolonged/awkward postures at home
*Use of household tools
*Activities involving repeated heavy lifting, bending,
twisting or reaching
ERGONOMIST’S PERSPECTIVE OF
THE DENTAL HYGIENE WORKPLACE
WORK PLACE
ENVIRONMENT
DENTAL HYGIENE
WORK
ENVIRONMENT
ALTERATIONS TO REPETITIVE
DENTAL HYGIENE STRAIN INJURIES
PRACTICE
Ergonomic design
&lay out
Layout
&convenience of
equipment
placement in
treatment area
• Eliminate
stretching for
dental
light&bracket
table
• Reduce twisting
motion of the
back,shoulders
&elbow while
reaching for
instruments
•Lumbar joint
dysfunction
•Carpal tunnel
syndrome
•Thoracic outlet
compression
•Tension neck
syndrome
Worker
&equipment
crossing point
•Dull hand
instruments
•Vibrations&stress
from rotary
instruments
•Improperly
designed hand
instruments
•
Tasks &work to be
performed
•Repetitive
movements&hand
fatigue
•Clinician fatigue
&stress on body
•Change clinician
positions
•Alternate
instrument handle
design&diameter
•Use proper
client&clinician
positioning
Psychological
aspects &factors
Practice
•Alternate involved
management&appoi dental treatments
ntment scheduling
with less
complicated
maintenance
appointments
•Lengthen
appointment times
•
•
Maintain hand
instruments
Do not use
handpieces with
curly or
retracting cords
Use balanced
instruments
•Carpal tunnel
syndrome
•Trigger finger
nerve syndrome
•De quervain’s
syndrome
•Lumbar joint
dysfunction
•Carpal tunnel
syndrome
•Cervical
spondylosis
•Strained pronator
muscle
•Tension neck
syndrome
•Adhesive capsulitis
•Strined pronator
muscle
•Lateral
epicondylitis
FACTORS LEADING TO REPITITIVE
STRAIN INJURIES
ERGONOMIC FACTORS IN DENTISTRY
GOOD PRACTICES
BALANCE & EXCERCISE
STAFF TRAINING
ERGONOMICS
WORK PLACE
CHANGES
EQUIPMENT DESIGN
INSTRUMENT DESIGN
1)ENVIRONMENTAL FACTORS
-Flexibility of muscles & tendons is important
for reducing the occurence of RSI.Flexibility can
be accomplished through physical exercise &
maintaining comfortable room temperatures.
-colder the room the less relaxed & flexible are
muscles &tendons.
-relaxed atmospheres with minimal background
noise contribute to a positive psychological state
for clinician & clients
2)EQUIPMENT FACTORS
DENTAL UNIT
-Treatment area consists of the dental unit & chair,
dental light, clinician’s chair
DENTAL CHAIR
•EQUIPMENT
•DESCRIPTION &USE
•Contoured seat
•Should provide comfort to a variety of clients
during treatment
•Lumbar support
•A contoured design gives additional support to the
torso&lumbar region
•Arm rests
•Support the client’s arms comfortably
•Foot or side power controls
•Move chair up/down &into a fully supine poosition
•Provides options to the clinician to access all
areas of client’s mouth with minimum back&neck
strain
•Foot controls provide clinician with extra
adaptability &range of motion
•360degree rotation lever or foot
control
•Allows dental chair to be rotated 360degree.
•Beneficial to provide access for wheel chair bound
clients
•Benefits left handed clinician to adjust the dental
chair for proper clinician/client positioning
DENTAL UNIT
EQUIPMENT
DESCRIPTION &USE
•Dental chair
Support client
•Dental light
Transmit illumination into client’s oral cavity
•Handpiece lines
Attach motor driven handpiece from the power
source to the dental unit
•Water lines
Bring water to various parts of the dental unit
including handpiece,three-way syringe,cup filler
•Three-way syringe
Provides air,water or a combination of air&water
•Evacuation lines
High speed/low speed suction with autoclavable
or disposable attachment tips
•Instrument tray
Movable stainless steel instrument tray usually
attached to the dental light post
• cuspidor
Movable cup or bowl utilized for expectoration
by the client;many are equipped with a water
flush system&many have a disposable paper lining
•Cup filler
Automatic water cup filler is activated by sensors
when the disposable cup is empty
CLINICIAN’S CHAIR
-Should have a broad,heavy base &be readily mobile
with a minimum of five rolling casters to maneuver
around the client’s head during care
-The seat of the chair should allow for adequate body
support&be adjusted easily for proper heights so the
clinician’s feet are flat on the floor with thighs
parallel with the floor
-Too high chair position causes body weight to be
supported by the spine,back &shoulders
-Too low position causes clinician to slump &sit with a
curved spine
CORDS ON POWERED INSTRUMENTS
Dental units are equipped with power –driven
instruments &air/water syringes.These may be
attached to the dental unit via:
Retractable cords-retract back into the dental unit to
save space &avoid tangling
Curly cords-coiling characteristics allow cord to hang
down a shortened distance&save space
Straight cords-straight,free hanging cord
Retractable &curly cords are encumbering and
repetitive pulling motion increases fatigue
&shoulder,arm muscle strain
A straight cord creates no tension while the clinician
is using the motor driven instrument.
3)POSITIONING FACTORS
*Wrist,arm,elbow &shoulder position
Shoulders-held in the lowest,most relaxed position
Elbow-held close to clinician’s body at a 90degree
angle
Arm-forearms held in the same plane as the wrist
&hand
Wrist-should never be bent;it is held straight
*Back &neck support
- poor posture of the clinician results in uneven
support of the spine &rupture of an intervertebral
disc
*Head position
-aligned with the spine
-head is erect
*Eyes
-directed downward
-distance from eyes to client’s oral cavity is
approximately 14-16inches
OPTIMAL OPERATOR POSITIONING
*Position the head as upright as possible
*Ensure that the back is straight&supported by a back
rest
*Keep elbows close to the body
*Keep thighs parallel to the floor
*Work from a neutral position
*Reposition the patient as necessary rather than
reaching, leaning & bending for access
4)PERFORMANCE FACTORS
*GRASP & FULCRUM
Fundamentals of grasp include holding the
instruments firmly,maintaining a secure grip &
maintaining control of the instrument without causing
undue strain or fatigue to the clinician’s hand,arms
&shoulders.
Modified pen grasp
Palm grasp
*FULCRUM &HAND STABILIZATION
-Fulcrum
area on which the finger rests & against
which it pushes while performing instrumentation.
-fulcrum provides a basis for steadiness &control
during stroke activation
-utilization of a proper fulcrum &hand stabilization
reduces RSIs
Intraoral fulcrum
-established by resting the pad of the ring finger
(fulcrum finger)inside the mouth against a tooth
surface
-pivoting on the fulcrum finger helps to maintain a
firm grasp,stability &proper wrist motion
Extraoral fulcrum
-positioned outside of the client’s mouth
-decreased chance of RSI by offering clinician less
cumbersome ways to instrument hard-to-reach areas of
client’s mouth.
when no fulcrum is used ,lateral pressure on the
instrument during activation
slipping of instrument.
To stabilize the instrument & gain control,clinician will
automatically tighten the grasp on the instrument.This
places stress on hand&arm muscles,tendons,ligaments
leading to increased
occurence of RSI
•WRIST MOTION DURING INSTRUMENT ACTIVATION
-Pivoting on the fulcrum causes hand,wrist &
forearm to move in one unified motion called’’wrist
rock’’.Failure to instrument using the unified motion
causes clinician to extend or flex the wrist.This
contribute to RSIs.
-Use of digital motion(push/pull motion of
instruments by utilizing only digits or fingers)
during instrument activation contributes to RSIs
•APPOINTMENT MANAGEMENT
-Alternate new clients with continued clients
-alternate root debridement &therapeutic scaling
with maintenance appointments
-alternate difficult appointments with less tasking
ones
-allow for ‘’buffer time’’ in daily schedule
5)INSTRUMENT FACTORS
*ERGONOMIC INSTRUMENT HANDLES
-larger in diameter&lighter in weight
-function of large diameter handles
to open the
grasp just enough to dissipate the mechanical forces
over a large area of muscles
-alternate use of different hand muscle groups(while
using instruments with several styles of handles)
decreases the occurence of RSI
*BALANCED INSTRUMENTS
-means working end is centered over the long axis of
the instrument handle
-balanced instrument
lateral pressure placed on
instrument activation will be aimed toward the
working end.
-not balanced
lateral pressure
causes
instrument to turn slightly in clinician’s fingers
to compensate this
clinician grasp instrument
handle tighter
RSI
*MECHANIZED INSTRUMENTS
-
*VIBRATING INSTRUMENTS
-
Use of ultrasonic &sonic instruments reduces
repitative hand instrumentation motions
cause fatigue &hand,arm,shoulder muscle strain.
REPETITIVE STRAIN INJURIES
1)HAND,WRIST
&FINGER INJURIES
CARPAL TUNNEL SYNDROME
-about 19-33% of the dentists report symptoms of
CTS
-occurs when the median nerve become compressed
within the carpal tunnel
-function of the median nerve is sensory&motor;it
supplies sensation to the thumb,index finger,middle
finger &half of the ring finger
-carpal bones of the wrist &transverse carpal
ligament form the carpal tunnel.Inside the tunnel
are 9 flexor tendons &median nerve
SYMPTOMS
-Earliest sign
numbness in the area supplied by
median nerve
-pain in the hand,wrist,shoulder,neck,lower back
-nocturnal pain in the hand &forearm
-pain in the hand while working
-morning stiffness &numbness
-loss of strength in hand;weakened grasp
-cold fingers
-increased fatigue in fingers,
hand,wrist,forearm,shoulders
CHAIRSIDE PREVENTIVE MEASURES
-Maintain good operator posture
-neutral forearm &wrist position:avoid pinching the
median nerve in the carpal tunnel
-keep shoulders relaxed
-use a unified motion(wrist,hand,forearm)during
scaling&polishing;avoid flexion &extension of the
wrist
-avoid extremes in temperatures
- limit exposure to vibrating instruments
-avoid forceful pinching &gripping of instrument
handles
-wear properly fitting gloves
-perform tendon gliding exercises
ASSESSING SYMPTOMS
-If symptoms are felt in the little finger
&right half of the ring finger
not CTS
2 TESTS:
•PHALEN’S TEST-place the back of the hands
against each other.Hold flexed wrists together at
a 90degree angle for 1minute.Subjective sensory
changes will be felt within 1minute.Sensory
changes indicate a +ve test.
•TINEL’S SIGN-entails tapping of the median
nerve at the ventral side of the wrist.If nerve
compression is present,sensation is felt in the
fingers.The sensation could range from a tingling
feeling to an electrical type shooting pain.
TREATMENT
Conservative treatment
•Corticosteroid injections-to reduce inflammation
•Iontophoresis-an electrical current delivery system
of corticosteroid
•Antiinflammatory medications &vitamins
•Wearing a wrist brace during early stages
Surgical treatment
•Transverse carpal ligament is cut to relieve pressure
on the median nerve
•New procedure-use an endoscope or small fiber optic
camera &a procedure similar to traditional surgery
except that no incision is made in the palm
(a small incision is made in the wrist).
COMMON DRUG THERAPIES FOR CTS
• Anti inflammatory drugs
-naproxen sodium 550mg tablets
-prednisone 10mg tablets
-aspirin 325mg tablets
• Vitamins
-B6
•THORACIC OUTLET COMPRESSION
-RSI resulting in compression of the brachial artery
&plexus nerve trunk at the thoracic outlet
-affects hand,wrist,arm &shoulder
-compression of the neurovascular bundle (brachial
plexus,subclavian artery,subclavian vein) results in
decreased blood flow to the nerve functions of the
arm
-compression occurs at the neck where the scalene
muscles create an outlet or tunnel.The nerves
&bloodvessels run from the neck into the arm &hand.
SYMPTOMS
-Numbness &tingling along the side of the arms
&hands
-neck &shoulder muscle spasms
-weakness &clumsiness in the
hand &fingers
-coldness of the extremities
-absence of radial pulse
RISK FACTORS
-Poor posture
-tilting of the head too much
-hunching of the shoulders
-positioning dental chair too
high
CHAIR SIDE PREVENTIVE MESURES
-Maintain proper clinician positions:head
erect,back straight,shoulders in neutral position
-proper height of the dental chair&client
positioning
ASSESSING SYMPTOMS
-signs relate to both decreased motor
function(nerve compression)&arterial
symptoms(decrease blood flow).
TEATMENT
•Initially-physical therapy,strengthening of shoulder
muscles,posture retraining exercises
•Surgery-directed at reducing source of compression
•SURGICAL GLOVE INJURY
-ill fitting gloves contribute to this
SYMPTOMS
-Commonly mistaken for CTS &TOC
because of similar symptoms
-tingling in the fingers
-cold extremities
-loss of muscle control &hand
strength
-numbness or pain in fingers
RISK FACTORS
-wearing gloves too tight-compromises proper
circulation to clinician’s hands &fingers
-wrist is also at a risk if additional pressure is placed on
the carpal tunnel by a glove that is too tight across the
wrist.
-wearing gloves too loose-cause clinician to grasp the
instrument handle tighter to compensate for the
feeling of lack of control.
CHAIR SIDE PREVENTIVE MEASURES
-Wear properly fitting gloves
-do tendon gliding exercices &stretch the hand &fingers
ASSESSING SYMPTOMS
If symptoms arrest when gloves
are taken off or when different
gloves are worn
SGI
TREATMENT
-Wear properly fitting gloves
-if pressure to the wrist
&compression of the median
nerve in the carpal tunnel
continue treatment as seen in
CTS.
•GUYON’S CANAL SYNDROME
-caused by ulnar nerve entrapment at the wrist.
-this syndrome differs from CTS in that the ulnar nerve
does not pass through the carpal tunnel.It passes
through a tunnel formed by the pisiform &hamate
bones&the ligaments that connect them.
SYMPTOMS
-Numbness &tingling in the little finger &the right
side of the ring finger
-loss of strength in the lower forearm
-loss of movement of the small muscles in the hand
-clumsiness of the hand
RISK FACTORS
-Holding the little finger a full span away from the
hand &fulcrum finger causes nerve entrapment
&symptoms of GCS.
CHAIRSIDE PREVENTIVE MEASURES
-Repositioning of the little finger while scaling
&polishing
-periodic hand stretches
ASSESSING SYMPTOMS
-affect little finger &half of the ring finger
TREATMENT
Conservative treatment
-hand strengthening exercises
-wearing a hand/wrist splint at night to decrease
pinching of the ulnar nerve
-antiinflammatory medications
Surgery
-relieve ulnar nerve entrapment
-cutting of the guyon’s canal is completed
•TRIGGER FINGER NERVE SYNDROME
-Affects the movement of the tendons
as the fingers &thumb are bent and
moved.
-inflamed tendons &tendon
sheaths,thickened tenosynovium
Nodule formation (from constant
irritation of pulling the tendon)
-as finger is flexed,nodule passes under
the ligament &becomes stuck.finger
cannot be extended back to its original
position
SYMPTOMS
-Inability to extend the fingers or
thumb after they are flexed.
RISK FACTORS
-Repititive use of fingers &hands
-digital motion during instrumentation
-pinching the instrument handle
CHAIRSIDE PREVENTIVE MEASURES
-Minimizing finger motion&utilization of proper grasp,
fulcrum &unified motion of the hand,wrist,forearm
-grasp the instrument handle using the pads of the
fingers &thumb instead of pinching with the tips of the
fingers
ASSESSING SYMPTOMS
When a nodule forms on the tendons of the fingers or
thumb,a palpable click will be felt as the nodule snaps
under the finger pulley
TREATMENT
Initial treatment with corticosteroids-reduce
inflammation& shrink the nodule to relieve
triggering
Surgery- a small incision made in the palm to
locate the pulley in question, it is cut
•DE QUERVAIN’S SYNDROME
-inflammation of the tendons &tendon sheaths at the
base of the thumb or ‘’anatomic snuff box’’
SYMPTOMS
-Aching &weakness of the thumb(along the base)
-pain migrating into the forearm
RISK FACTORS
-repetitive ulnar deviation of the wrist while reaching for
instruments or during instrumentation
-twisting &bending the wrist in an ulnar direction
-using a forceful grip on the instrument handle
CHAIR SIDE PREVENTIVE MEASURES
-Avoid ulnar wrist deviation during instrumentation
-eliminate twisting of the wrist when reaching for
instruments
-maintain a neutral wrist position &unified motion
during dental care procedures
ASSESSING SYMPTOMS
 Finkelstein’s test-bend the thumb into palm of the
hand.Grasp the thumb with 4 fingers.
Place the wrist in the ulnar deviation position by bending
the wrist toward little finger.
Pain over the tendons &tendon sheaths at the base of
the thumb indicates the syndrome.
TREATMENT
•Milder cases-anti inflammatory medication,
immobilization of the wrist, a wrist splint, or
ergonomic adjustments to the work environment.
•When simple measures fail-corticosteroid injections,
progressive physical &occupational therapy
•Severe/chronic cases-surgery(relieving pressure on the
tendon)
2)ELBOW &FOREARM INJURIES
• STRAINED PRONATOR MUSCLE
-muscle involved in SPM is an elongated narrow
pronator muscle in the forearm flexor of the elbow joint.
-caused by compression of the median nerve as it passes
under the pronator muscle. The pronator muscle wraps
around the anterior aspect of the elbow.
SYMPTOMS
-Similar to those of CTS
RISK FACTORS
-Repetitive &constant holding of the arms away from
the body with the palm &thumb side of the hand rotated
downward during instrumentation
CHAIR SIDE PREVENTIVE MEASURES
-Maintain neutral arm position: hold the arms close to the
body
-maintain neutral wrist position
-avoid rotation &twisting of the forearm
ASSESSING SYMPTOMS
-Phanel’s&Tinel’s test-rule out CTS
TREATMENT
-anti-inflammatory medication
-corticosteroid injections
-environmental changes in work place
•LATERAL EPICONDYLITIS
-Known as tennis elbow, a degenerative disorder of the
elbow
-resulting from inflammation of the wrist extensor
tendons on the lateral epicondyle of the elbow.
SYMPTOMS
-Aching or pain in the elbow
- sharp shooting pain during elbow extension
RISK FACTORS
-Repetitive &constant use of a forceful grip or grasp
-forceful wrist &elbow movements
CHAIR SIDE PREVENTIVE MEASURES
-Maintain neutral wrist position during instrumentation
- utilize proper clinician positions
ASSESSING SYMPTOMS
-palpation of the wrist extensor muscles at the lateral
epicondyle of the elbow during resisted wrist extension. Pain
during this may indicate LE
TREATMENT
-rest
-use of anti-inflammatory medications
-alterations in the work environment
-a wrist splint to eliminate wrist extension
-physical therapy
-corticosteroid injections
•RADIAL TUNNEL SYNDROME
-A condition affecting the radial nerve as it is entrapped in
the radial tunnel
SYMPTOMS
-pain at the lateral side of the elbow when the arm
&elbow are being used
CHAIR SIDE PREVENTIVE MEASURES
-maintaining proper wrist position &motion
ASSESSING SYMPTOMS
-often mistaken for LE
-electrical tests must be performed on radial nerve
-history must be assessed
TREATMENT
-rest
-anti-inflammatory medication
-surgery to relieve tension &pressure on radial nerve
CUBITAL TUNNEL SYNDROME
-condition affecting the ulnar nerve as it crosses
behind the elbow
-when the elbow is bent, the nerve is pulled up
between bones causing compression & entrappment
of the ulnar nerve
SYMPTOMS
Pain & numbness in the outer side of the ring finger &
little finger
Pain sometimes relieved when the elbow is straightened
RISK FACTORS
Prolonged gripping or grasping of instruments in the
palm of hands
Holding the elbow in a flexed position during
procedures
CHAIR SIDE PREVENTIVE MEASURES
-maintain a neutral elbow position
-alter instrument grasps
-Avoid prolonged use of palm grasp
-Avoid leaning on the elbow when sitting at a table
ASSESSING SYMPTOMS
Pain or numbness usually disappear while straightening
the elbow
TREATMENT
Physical & occupational therapy
Anti inflammatory medications
Use of an elbow extension splint
Surgery- creates a new cubital tunnel for ulnar nerve
3)SHOULDER INJURIES
TRAPEZIUS MYALGIA
Caused by static loading in the shoulder or stabilizing
muscles over a long period of time
SYMPTOMS
Pain & tenderness in the descending part of the
trapezius muscle
RISK FACTORS
Long dental procedures which cause clinician to remain
in one position for too long
CHAIR SIDE PREVENTIVE MEASURES
Manage appointment times
Take break during long procedures
Change body positions
ASSESSING SYMPTOMS
Consistent pain & tenderness in the area of trapezius
muscle
TREATMENT
Rest
Physical therapy
Stretching exercises
Massage
ROTATOR CUFF INJURIES
Include rotator cuff tendinitis & rotator cuff tears
Both affect the connective tissue in the shoulder &
both are common causes for pain in the shoulder
SYMPTOMS
Pain when lifting the arm 60-90°
Functional impairment
RISK FACTORS
Static loading on the shoulder muscle
Improper body support
CHAIR SIDE PREVENTIVE MEASURES
Avoid repetitive twisting & reaching for dental
instruments
Maintain neutral shoulder & arm positions
ASSESSING SYMPTOMS
Constant pain in shoulders & increasd pain when raising
the arms
MRI & further medical testing
TREATMENT
Active rehabilitation partnered with corticosteroid
injections & anti inflammatory medications
-Surgery
ADHESIVE CAPSULITIS
-frozen shoulder
-results from immobility of the shoulder due to severe
injury to shoulder or repeated occurrence of rotator
cuff tendonitis
SYMPTOMS
-Pain in shoulders
-limited range of motion of the shoulder
CHAIR SIDE PREVENTIVE MEASURES
-avoid repetitive twisting &reaching for instruments
-maintain proper shoulder &arm positions
ASSESSING SYMPTOMS
-limited range of motion &constant pain in shoulder
during lifting of the arms along with history of rotator
cuff tendonitis
TREATMENT
-physical therapy
-anti inflammatory drugs
-heat/ice regimens
-noninvasive treatment of forced shoulder movement
with use of general anesthetic
if therapy fails
NECK &BACK INJURIES
LUMBAR JOINT DYSFUNCTION
-occurs from repetitive &continued twisting and
rotating of the spine
-improper support of spine
intervertebral discs are put under tremendous pressure
injury
SYMPTOMS
-discomfort &pain in the lumbar region of the spine
RISK FACTOR
-Too much rotation of the midsection of the body
create strain on the lumbar curve
CHAIR SIDE PREVENTIVE MEASURES
-Avoid twisting the back &spine
-properly support body weight
-modified equipment placement to avoid twisting to
reach instruments
ASSESSING SYMPTOMS
-constant lower back pain
-limited movement of back &spine
TREATMENT
-rest
-workplace adjustments
-physical therapy
-drug therapy
-surgery
TENSION NECK SYNDROME
-tension myalgia
-involves the cervical muscles of the trapezius
muscle
SYMPTOMS
-pain or stiffness around the cervical spine in the
neck
-pain between the shoulder blades; pain may also
radiate down the arms
-muscle tightness &tenderness in neck
-limited neck movement
RISK FACTORS
-improper positioning of clinician’s head &neck during
procedures
-bending of neck result in pressure &stress on cervical
spine
CHAIR SIDE PREVENTIVE MEASURES
-maintain proper clinician head &neck position to
support neck &spine
-maintain proper height of dental chair
-support weight of the head properly over the entire
spine not just with cervical portion of the spine
-keep the back straight during procedures
-periodic breaks &stretching exercises
ASSESSING SYMPTOMS
-If limited neck motion with pain &discomfort
TREATMENT
-Physical therapy
-stretching exercises
-massage therapy
-ultrasonic &electrical muscle stimulation to increase
blood flow
CERVICAL SPONDYLOSIS &CERVICAL DISC DISEASE
- lead to degeneration of the cervical spine
-affect the neck, scapula, shoulders, arms causing
osteoarthritis of cervical spine &disc degeneration.
SYMPTOMS
-stiffness &limited motion of neck
-crepitus during active or passive movements of neck
-pain in the upper/middle cervical region of spine
-pain in scapula of shoulder regions
-muscle spasms
RISK FACTORS
-repeated stress &strain placed on the neck &cervical
spine
CHAIR SIDE PREVENTIVE MEASURES
-maintain proper head &neck position during
instrumentation
-properly seat clients for easy access to the mouth
ASSESSING SYMPTOMS
-monitor occurrence of pain during neck motion &
crepitus in the cervical spine
TREATMENT
-posture retraining exercises
-strengthening exercises for neck &back muscles
-rest
-anti-inflammatory drugs
-cervical collar
-physical therapy
MUSCLE STRENGTHENING EXERCISES
Help keep the muscles strong &healthy
To warm the muscles &joints of your hands, slowly
open &close your hands which ends with your fingers
tucked into your palm, also press your palms together
&then relax them.
Hold one arm out in front of your body with your hand
extended. With fingers of other hand gently pull back
extended fingers to increase the stretch
To relieve eye strain look up &focus eyes at a distance
for about 20 seconds
Head rotations for neck stiffness
Shoulder shrugging-pull shoulders up toward ears &
then roll them backward &forward in a circular motion.
EYE TO THE FUTURE
To enjoy a healthy and pain free career, you must keep
your muscles, tendons, nerves, joints healthy.
Remember to apply ergonomic principles in all of your
daily activities. Do not ignore early signals of pain and
stiffness. The longer the symptoms are ignored, the
more severe the damage. Dentistry can be a physically
stressful profession, but it is also a very rewarding
profession that benefits both practitioners and
patients.
CONCLUSION
Begin to make some changes in the way you
practice by incorporating some of these suggestions
into your regular routine during the work day. You
will find that you have less fatigue at the end of the
day, experience less pain and you will be able to
provide the quality of service that you and your
patients demand.
REFERENCE
• Dental hygiene theory and practice- Darby & Walsh
• Modern dental assisting- Doni.L.Bird &
Debbie.S.Robinson
• Internet(colin@employeeergonomics.com)
THANK YOU…