Ergonomics for
the Office
by
Cristiana K. Collins , PT, MA, NCS
December 2008

What is “ergonomics”?
• ergo (work) + nomos (natural law)
• Fitting the task to the worker
• Fitting the environment to the worker

Why?
• Poor office ergonomics has been shown to
cause:
– repetitive stress injuries
• wrist
• elbow
– back pain
• upper back
• lower back
– neck pain
– leg pain

Why?
• Working posture and musculoskeletal
health are related ( J Occup Rehab, June
2004)
• Office ergonomics programs reduce
musculoskeletal injuries (Int J Occup Safety
& Erg)

Office Ergonomics
Sitting posture
Chair
Desk
Computer

Sitting Posture

Proper Sitting Posture
• Neutral pelvis
• Neutral spine
• Neutral shoulders/upper
extremities/wrists
• 90/90/90 position of
hips/knees/ankles
• Proper chair height
• Proper chair depth
• Proper support

Neutral Pelvis
• Support is
needed to
maintain a
neutral pelvis

Neutral Pelvis

Neutral Pelvis

Neutral Spine
cervical/thoracic/lumbar

Neutral Spine
A lumbar support
can ONLY support
the spine, it
CANNOT create a
neutral posture

Neutral Spine

Neutral shoulders/upper extremities/wrists
• Shoulders:
– Not elevated, not
rotated
• Upper Extremities:
– Comfortably resting
by the side of the
body
• Wrists:
– In a neutral position,
supported on a gel
pad, resting
comfortably on the
keyboard

90/90/90 position of
hips/knees/ankles
• Hips:
– 90 degrees
– Thighs supported by seating
surface
• Knees:
– 90 degrees
– 2-3 finger clearance from
seat to back of knee
• Ankles:
– Preferably at 90 degrees
– Supported on foot support

Proper Sitting Posture in relation to
your computer station
*Eye Level at center
of monitor (or *Mouse by side of
slightly higher) keyboard
*Keyboard at *Headset (for high
Forearm Level phone usage)
*Wrist Supported

Proper Sitting Posture in relation to
your computer station

• Proper chair height
• Proper seat depth
• Proper support

Stability vs. Mobility
• Stability
• Mobility
• Functional Mobility/Stability

Common Problems/Mistakes
• Monitor too high/too low
• Monitor not properly aligned
• Key board on desk
• Key board too high/too low

Common Problems/Mistakes
• Key board tilted improperly
• Mouse on desk
• Chair too high/too low
• Back of chair too low
• Phone use while typing

Common Compensations
• Forward head
• Rounded
(slouched) back
• Pelvis posteriorly
tilted

Common Compensations
• Rotated neck
• Elevated/depressed
shoulders
• Arms resting on arm
rests
• Wrists in excessive
extension or flexion
• Feet dangling or
tucked under seat

Look familiar?

What are the consequences
of these postures?
• Musculoskeletal imbalances
• Repetitive injuries
• Soft tissue strains
• Visual strains
• Pain
• Headaches
• ‘itis’
• And the list goes on…….

What happens with laptops?

The Ideal Set-up

Simple Corrections
• Provide support for a
neutral pelvis:
– Forward leaning
chair
– towel roll
under/behind sit
bones

Simple Corrections
• Provide support for a
neutral spine:
– A lumbar cushion should
SUPPORT the lumbar
spine in neutral and NOT
attempt to position it in
neutral

Simple Corrections
• Provide support for
feet and legs:
– Your thighs should be
supported by your
weight bearing feet

Simple Corrections
• Use an adjustable
height keyboard and
mouse tray
http://www.fentek-
ind.com/keyboardtrey.htm

Simple Corrections
• Adjust the height of
the monitor

Ergonomic Laptop Use

Questions?

Thank you!