ERGONOMICSERGONOMICS

By By

Raylene M. Blandino M.S., PA-CRaylene M. Blandino M.S., PA-C

ERGONOMICS-What is it?ERGONOMICS-What is it?

Derived from two Greek words:Derived from two Greek words: ““Nomoi” meaning natural lawsNomoi” meaning natural laws ““Ergon” meaning workErgon” meaning work Hence, ergonomists study humanHence, ergonomists study human

capabilities in relationship to workcapabilities in relationship to work

demandsdemands

HistoryHistory

• As early as 18As early as 18thth century doctors noted century doctors noted that workers who required to maintain that workers who required to maintain body positions for long periods of time body positions for long periods of time developed musculoskeletal problems.developed musculoskeletal problems.

• Within last 20 years research has Within last 20 years research has clearly established connections clearly established connections between certain job tasks and RSI or between certain job tasks and RSI or MSD.MSD.

1)1) Static workStatic work: musculoskeletal effort : musculoskeletal effort required to hold a certain position, required to hold a certain position, even a comfortable one.even a comfortable one.

Example: sit & work at computers; Example: sit & work at computers; keeping head and torso upright keeping head and torso upright requires small or great amounts of requires small or great amounts of static work depending on the efficiency static work depending on the efficiency of the body positions we chose.of the body positions we chose.

What two elements What two elements are at work? are at work?

Elements at work (cont)Elements at work (cont)

• ForceForce: : amount of tension our muscles generateamount of tension our muscles generate Example: tilting your head forward or backward Example: tilting your head forward or backward

from a neutral, vertical position from a neutral, vertical position quadruplesquadruples the the amount of force acting on your lower neck amount of force acting on your lower neck vertebraevertebrae

• Increased force is d/t increase in muscular Increased force is d/t increase in muscular tension needed to support head in a tilted tension needed to support head in a tilted positionposition

3 Main Ergonomic 3 Main Ergonomic Principles:Principles:

1.1. Work activities should permit worker to Work activities should permit worker to adopt several different healthy and safe adopt several different healthy and safe postures.postures.

2.2. Muscle forces should be done by the Muscle forces should be done by the largest appropriatelargest appropriate muscle groups muscle groups availableavailable

3.3. Work activities s/b performed with joints Work activities s/b performed with joints at about mid-point of their ROM (esp. at about mid-point of their ROM (esp. head,trunk,UE)head,trunk,UE)

• The average person working at a The average person working at a keyboard can perform 50,000 to keyboard can perform 50,000 to 200,000 keystrokes a day200,000 keystrokes a day

• Overexertion, falls & RMI are the most Overexertion, falls & RMI are the most common cause of workplace injurycommon cause of workplace injury

• An average of 125,000 back injuries An average of 125,000 back injuries due to improper lifting each year.due to improper lifting each year.

• Muscles overuse results in tiny tears in Muscles overuse results in tiny tears in the muscles and scarring; these the muscles and scarring; these contribute to inflammation and muscle contribute to inflammation and muscle stiffnessstiffness

FACTS

A Bit of A Bit of AnatomyAnatomy !! !!

• Overuse and small repetitive movements ie: Overuse and small repetitive movements ie: CTD, RSI, MSD disturb balance of muscles, CTD, RSI, MSD disturb balance of muscles, tendons, ligaments and nervestendons, ligaments and nerves

• Brachial plexus: nerve group that supply Brachial plexus: nerve group that supply muscles and skin of UE, course down side of muscles and skin of UE, course down side of front of neck and become median, ulnar and front of neck and become median, ulnar and radial nerves.radial nerves.

• Nerves send signals to muscles to contractNerves send signals to muscles to contract• When nerve compressed feel sensation When nerve compressed feel sensation

somewhere b/w point of compression and somewhere b/w point of compression and fingertipsfingertips

WhatWhat causes Nerve causes Nerve Compression or Compression or

EntrapmentEntrapment??1)1) Repeated motionsRepeated motions

2)2) Tight musclesTight muscles

3)3) Inflammation of surrounding tissuesInflammation of surrounding tissues

4)4) Misalignment of the nerveMisalignment of the nerve

What are 4 Common Nerve What are 4 Common Nerve injuries?injuries?

I.I. Thoracic Outlet Syndrome:Thoracic Outlet Syndrome: brachial brachial plexus compression d/t muscle plexus compression d/t muscle tightness side of neck from poor tightness side of neck from poor head position or slumped posture. head position or slumped posture.

S/Sx: numbness/tingling in hand, S/Sx: numbness/tingling in hand, made worse w/overhead activities made worse w/overhead activities or cradling phone b/w ear and or cradling phone b/w ear and shouldershoulder

Nerve injuries (cont)Nerve injuries (cont)

II.II. Radial tunnel syndrome:Radial tunnel syndrome: compressed radial nerve @ outside compressed radial nerve @ outside of elbow d/t repetitive wrist & of elbow d/t repetitive wrist & finger extension or turning of finger extension or turning of forearmforearm

S/Sx: Sensations from elbow to S/Sx: Sensations from elbow to base of thumb w/ wrist weakness a base of thumb w/ wrist weakness a common sxcommon sx

Nerve injuries (cont)Nerve injuries (cont)

III.III. Cubital tunnel syndrome:Cubital tunnel syndrome: ulnar ulnar nerve compression inside of the nerve compression inside of the elbow d/t repetitive bending of elbow d/t repetitive bending of elbow or elbow or resting your elbowresting your elbow on a on a hard surfacehard surface

S/Sx: numbness or tingling and S/Sx: numbness or tingling and inside of arm w/ tingling to ring & inside of arm w/ tingling to ring & little fingerslittle fingers

Nerve injuries (cont)Nerve injuries (cont)

IV.IV. Carpal tunnel syndrome:Carpal tunnel syndrome: compression of compression of median nerve at level of carpal tunnelmedian nerve at level of carpal tunnel

Where is carpal tunnel? Formed @ wrist by Where is carpal tunnel? Formed @ wrist by ligament over the carpal bones in handligament over the carpal bones in handS/Sx: numbness or tingling in thumb, index, S/Sx: numbness or tingling in thumb, index, or middle finger & ½ of ring finger; often or middle finger & ½ of ring finger; often awakened @ night by hand “falling asleep”awakened @ night by hand “falling asleep”Sx increased by driving or attempting to Sx increased by driving or attempting to hold objects; dropping objects is a common hold objects; dropping objects is a common complaintcomplaint

Tendons and TendonitisTendons and Tendonitis

• Tendons are connective tissue that attach Tendons are connective tissue that attach muscle to bone; have little stretch or reboundmuscle to bone; have little stretch or rebound

• Tendon overuse, static or prolonged Tendon overuse, static or prolonged position=inflammation or tendonitisposition=inflammation or tendonitis

• Tendons of wrist & hand very small; @ high Tendons of wrist & hand very small; @ high risk for injury w/ overuserisk for injury w/ overuse

• ““Tennis elbow” or lateral epicondylitis affects Tennis elbow” or lateral epicondylitis affects finger extensorfinger extensor tendons outside of elbow tendons outside of elbow

• ““Golfer’s elbow” or medical epicondylitis Golfer’s elbow” or medical epicondylitis affects finger flexor tendons inside of elbowaffects finger flexor tendons inside of elbow

What to do ??What to do ??

a)a) Warm up & stretch before activities that are Warm up & stretch before activities that are repetitive, static or prolongedrepetitive, static or prolonged

b)b) Take Take frequent breaksfrequent breaks from ANY sustained posture from ANY sustained posture every 20-30 minutesevery 20-30 minutes

c)c) Respect pain- positions or stop painful activityRespect pain- positions or stop painful activityd)d) Recognize early signs of inflammatory process, & tx Recognize early signs of inflammatory process, & tx

earlyearly

PREVENTPREVENT, , PREVENTPREVENT, , PREVENTPREVENT !!! !!!

e)e) Maintain erect position of backMaintain erect position of back& neck w/ shoulders relaxed & neck w/ shoulders relaxed

f)f) Position equipment & work directly in front of and close to Position equipment & work directly in front of and close to your major tasksyour major tasks

g)g) Keep upper arms close to the body, elbows 90-100 degreesKeep upper arms close to the body, elbows 90-100 degreesh)h) Keep feet flat on floor, upper body weight resting on “sits Keep feet flat on floor, upper body weight resting on “sits

bones”bones”i)i) Wrists as neutral as possible; safe zone for wrist movement Wrists as neutral as possible; safe zone for wrist movement

is 15 degrees in all directionsis 15 degrees in all directions

Maintain Neutral Posture

f)f) Avoid bending neck forward for Avoid bending neck forward for prolonged periods of time (*remember prolonged periods of time (*remember quadruplequadruple the force); use a copy holder the force); use a copy holder

g)g) Avoid static positions for prolonged Avoid static positions for prolonged time; muscles fatigue---MOVE to time; muscles fatigue---MOVE to circulation!circulation!

You talking to me?

Modify Tasks:Modify Tasks:

a)a) Alternate activities frequently; rotate Alternate activities frequently; rotate heavy &/or repetitive tasks w/ lighter less heavy &/or repetitive tasks w/ lighter less repetitive ones.repetitive ones.

b)b) If sx become worse If sx become worse REASSESSREASSESS task setup & task setup & look for alternative methodslook for alternative methods

c)c) Avoid repetitive or prolonged grip activitiesAvoid repetitive or prolonged grip activitiesd)d) Avoid pinching w/ wrist in flexion or wrist Avoid pinching w/ wrist in flexion or wrist

deviation (bending to side)deviation (bending to side)e)e) Take Take frequent breaksfrequent breaks to stretch & rest to stretch & rest

handshands

• Use the largest joints & muscles to do the Use the largest joints & muscles to do the jobjob

• Use 2 hands to lift rather than one, even Use 2 hands to lift rather than one, even with light objects and tasks.with light objects and tasks.

• Avoid lifting w/ the forearm in full pronation Avoid lifting w/ the forearm in full pronation (palm down) or supination (palm up)(palm down) or supination (palm up)

• Slide or push & pull objects instead of liftingSlide or push & pull objects instead of lifting

• Keep reaching to a minimumKeep reaching to a minimum

• Carry objects close to body at waist levelCarry objects close to body at waist level

Body Mechanics

Correct & Incorrect Correct & Incorrect TechniquesTechniques

Good and Bad of “Good and Bad of “ TILT”TILT”

ERGO REMINDERS from Stretchbreak.com

Practice Wellness at Work and Home !

ExerciseNutrition

Relaxation

Body Mind

Spirit

MOVE

BRE

AT

HE

STRETCH

An ounce of Prevention is An ounce of Prevention is worth a pound of cure !worth a pound of cure !