Upper Extremity MSDs Computer Workstations

Rosemarie A. Trigger, PT, CSHEPhysical Therapist, Certified Specialist in Health ErgonomicsPhysical Therapy Associates of Schenectady, P.C.

Upper Extremity MSDs

Carpal tunnel syndrome*Tendonitis*Bursitis*Tenosynovitis*Dequervain’s syndrome*Trigger finger*Epicondylitis– Tennis elbow– Golfer’s elbow

Rotator cuff syndromeThoracic outlet syndrome*Hand arm vibration syndromeSprains and strains– Sprain – injury to

ligamentous structure– Strain – injury to muscle or

tendon* Along with back and neck pain, most common MSDs seen in office/computer workers

Upper Extremity Anatomy

Postural Risk Factors

Extreme ROM posturesExtreme ROM postures– Close to end range– Require active and passive

stress forces– May exert compressive forces

on blood vessels

Static holdingStatic holding– Overloads joints against

gravity– Blood flow compromised –

can’t get in for nutrition or bring waste products out

Awkward posturesAwkward postures– Outside of neutral– Less efficient, fatigue easier– Muscles can create less force– Increases wear and tear on

sensitive structures like tendons, nerves, joints

Neutral upper extremity postures

Neutral wrist postures align forearm with the wrist and hand.

Resting position for joints – least amount of biomechanical strain.

Maintain NEUTRALNEUTRAL Wrist/Grip

Neutral gripEven more important with a loadEven more important with a load…….!!!.!!!

ELBOW PAIN? Wrist and hand positions may be the real cause!!

• Muscles attached on the bone on the outside of your elbow extend wrist and fingers, as well as turn your palm to facing up position

• Muscles attached on the bone on the inside of your elbow bend wrist and fingers, as well as turn your palm to facing down position

• Problems may be related to:– Repetitive wrist

and hand motions– Forceful gripping– Working in other

than neutral positions

Rotator Cuff Muscles…

…not only rotate your shoulder, but provide stability for all upper body activities!

Strengthen your rotator cuff to reduce shoulder injuries!

Reduce stress on carpal tunnelStretch frequentlyAlways work in neutral – keep wrists straightMaintain circulation – open/close hand, shake hands out, ROMInterrupt repetitious activitiesAllow adequate recovery time from repetition or forceful exertionAvoid activities that require excessive side to side or up and down movementAvoid pressure over forearm or heel of handMouse with open, relaxed hand

Posture and work tips

Ergonomists agreeErgonomists agree……All work activities should permit the worker to adopt several different, but equally healthy and safe postures.

Where muscular force has to be exerted it should be done by the largest appropriate muscle groups available.

Work activities should be performed with the joints at about mid-point of their range of movement. This applies particularly to the spine, trunk, and upper limbs.

Office Ergonomics

ChairMonitorKeyboardDocuments

MouseLightingPhone

Correct Sitting Posture

Sit in a straight back chairHips and buttocks touching the back of the chairFeet flat on floorGently roll the pelvis forward by creating a comfortable arch in the small of the backUse a rolled towel or lumbar roll in the small of the backSimultaneously, lift the chest, head above shoulders maintain upright sitting positionChin is parallel to floor

Anterior vs. Posterior Pelvic Tilt

Find your normal curve

Normal lumbar curve is in between a flat or rounded back position and excessive anterior tilt

Neutral Posture

3 curves in back should always be maintained…

– Standing– Sitting – Working – Sleeping– Playing

Adjust the chair first!

Adjust controls from a seated positionAdjust height so feet are supported on floor or footrestAdjust lumbar support and back tilt to promote neutral spine postureAdjust elbow height with arms relaxed next to trunk

Forearm are approx. 70-90° angle to upper armsSeat tilt lower in front of chair yields higher hips and back tiltKnees higher yields reclined position for back rest/reading materialsUse both to vary posture and different work tasks

Office chair wish list…

Lumbar back support or contour Waterfall seat designStable five-point baseWheels or casters suitable to type of flooringArmrests designed to support arms, shoulders, neck (adjustable)Adjustable seat height, and tilt mechanismAdequate width and adjustable depthNo pressure behind knees Swivel reduces trunk twistingDurability and adequate weight limits

Active vs. Passive Adjustability

Loads on spine are twice as high in flexed forward sitting as upright unsupported sittingTheoryTheory - passive ergo chairs are designed to continually adapt to the user to allow more natural changes in position – provides continual support as well

Not moving is harmful!Computer work diminishes opportunity to change posturesStatic and constrained postures interrupt blood flowFixed postures are as likely to lead to back pain as heavy laborLack of movement is associated with leg swelling

Keyboard and Mouse

Basic components:

–– POSITIONPOSITION – directly in front of trunk, elbows close to body, forearms parallel to floor; if necessary use articulating keyboard/mouse platform

–– HEIGHTHEIGHT – relative to sitting posture, chair and monitor

–– DISTANCEDISTANCE – keyboard platform ~ above thighs; mouse in same plane as keyboard or closer

Maintain neutral wrist posture

Wrists remain straight and floatfloat over keyboardPalms rest when notnottyping or mousingAvoid deviating wrists to right or leftConsider using a negative slope on your keyboard

Stretch Break…

Change position often to reduce stress and fatigueMove to maintain and improve circulation to musculoskeletal tissuesWarm-up and stretch to minimize discomfort and reduce risk of overuse problemsAt minimum rest 5 min per hour if repetitive typing

Monitor

Top line of text is slightly below eye level while seated15-60° viewing angleDistance eyes to screen at least arms lengthMonitor too close or too far may contribute to poor posture

Lighting and Glare

Inappropriate lighting for computer work may lead to eyestrain, headaches

or blurred vision.

•Light source should be parallel to your line of vision

•Never position desk directly in front of a window

•Monitors placed 90° to window reduce glare and reflection

•Close blinds to reduce direct light

•Clean monitor screen at least once per week

•Try task lighting

•Dark characters on light background less effected by reflection

•If florescent lighting is too bright, remove one bulb

•Eye exercises help!

Rearrange the work area…

Avoid reachingKeep most used objects closestAvoid twisting any body partIncline documents or use document holder Speaker or headsets for frequent phone use

Individual worker responsibilities…

Adapt job duties to abilities– Rotate job tasks to allow adequate recovery time

Adjust your work environment– Work at appropriate heights– Support body parts as necessary

Change your work habits– Warm up for work– Avoid awkward or prolonged postures, move frequently– Lift safely and use neutral postures

Exercise and stay healthy– Maintains strength, flexibility and cardiovascular status

Resources

GE Workstation Evaluation:

http://ehs.corporate.ge.com/fileDownload.jsp?docID=11843

GE EHS/Ergonomics Website

Workstation evaluation checklist:

http://www.osha.gov/SLTC/etools/computerworkstations/checklist.html

OSHA etools – computer workstations, workstation checklist, purchasing guide checklist – www.osha.gov

CU Ergo – Cornell University Ergonomics Web

http://ergo.human.cornell.edu/CUVDTChecklist.html

Contact us…

Rosemarie Trigger, PT, CSHEPhysical Therapy Associates

triggero@nycap.rr.com

Phone: 518-887-2533

Visit our Physical Therapy Associates website at:

www.physicaltherapyschdy.com