1. CEN3722 Human Computer Interaction Ergonomics
Dr. Ron Eaglin

2. Objectives Understand the meaning of Ergonomics
Know the basic Musculoskeletal Disorders (MSD’s)
Carpal Tunnel Syndrome
Tendonitis
Rotator Cuff
Epicondylitis
Trigger finger
Muscle strains and lower back injuries

3. Objectives
Know the adverse effects of preventable MSD’s on worker productivity
Know how ergonomics helps in prevention from these musculoskeletal disorders
Know regulations and protections for workers
Know how to develop a plan for prevention of MSD’s

4. Ergonomics Fitting the Person to the Job Risk Factors
Lifting heavy items (pushing and pulling heavy loads)
Bending and reaching (awkward body positions)
Performing tasks repetitively
Body position
By Yamavu - Own work, CC0,

5. MSD – Carpal Tunnel Syndrome
Numbness and tingling in the hand caused by a pinched nerve in the wrist
Very common (> 3 million US cases annually)
Many causes (common in many professions including computer)
Generally very preventable and easily treatable (including surgery)

6. MSD - Tendonitis Inflammation of tendons (microscopic tears)
Caused by overuse (too often) and overload (too much)
Can last a few days or weeks, risk of re-injury
Treatment – NSAIDS, ice packs, splinting

7. MSD – Rotator Cuff Form of tendonitis in shoulder joints
Not typically common as computer injury
Treatment and symptoms same as tendonitis

8. MSD - Epicondylitis
Commonly called tennis elbow (lateral epicondylitis) also golfers elbow (medial epicondylitis)
Also very common – racquet sports are a risk factor
Form of tendonitis and treatments are similar

9. MSD – Trigger finger
Tenosynovitis – finger gets stuck in a bent position
Inflammation narrows the space within the sheath surrounding finger tendons
Caused primarily by repetitive gripping actions
Treatment – rest, splint, NSAIDS

10. MSD – Lower back injury/pain
Very common in computer/office workers
Ensure correct ergonomic heights for office chair
Use of lower back supports
Regular posture/breaks/exercises/stretching/movement
True also for driving

11. Effects of MSD’s
MSD’s account for 33% of all worker injury and illness cases (BLS)
MSD’s are most frequently reported cause of lost or restricted work time.
Also strongly related to quality of life issues

12. Ergonomics - Prevention
Ensure any desk position follows ergonomic guidelines
Use practice of frequent breaks or exercises
Recognize signs of repetitive task injuries or tendonitis

13. Ergonomics – OSHA Protections
OSHA General Duty Clause
Employers must keep their workplace free from recognized serious hazards including ergonomic hazards.
The basic criteria OSHA will use in deciding whether to cite are those imposed by the General Duty Clause itself:
whether an ergonomic hazard exists
whether that hazard is recognized
whether the hazard is causing, or is likely to cause, serious physical harm to employees
whether a feasible means exists to reduce the hazard

14. Ergonomics Plans Management must support ergonomic process
Worker involvement
Workplace assessment
Identification or risks
Responsible for risk factor avoidance
Training on ergonomics and factors
Have reporting mechanism
Have evaluation process

15. Objectives Understand the meaning of Ergonomics
Know the basic Musculoskeletal Disorders (MSD’s)
Carpal Tunnel Syndrome
Tendonitis
Rotator Cuff
Epicondylitis
Trigger finger
Muscle strains and lower back injuries

16. Objectives
Know the adverse effects of preventable MSD’s on worker productivity
Know how ergonomics helps in prevention from these musculoskeletal disorders
Know regulations and protections for workers
Know how to develop a plan for prevention of MSD’s