KNR 342 Occupational Biomechanics

1. KNR 342Occupational Biomechanics Dr. Steve McCaw 227B Horton 438-3804 smccaw@ilstu.edu www.cast.ilstu.edu/mccaw

2. ErgonomicsErgo: work & nomos: natural laws • Management & labor recognize that injury and reduced performance reflect a mismatch between • the worker • Job demands • the task • the environment.

3. Hierarchical Goals of Occupational Biomechanics Generate • “tolerable” • “acceptable” • “optimal” working conditions

4. Factors Affecting Performance & Injury People are different. Individual body size & shape (anthropometrics)

5. Performance & Injury Individual body size & shape (anthropometrics) fitness level / injury history

7. Performance & Injury Individual body size & shape (anthropometrics) fitness level / injury history off-work activities

9. Performance & Injury Individual body size & shape (anthropometrics) fitness level / injury history off-work activities psychological status

10. Psychology of Recovery

11. Use it to your advantage

12. Performance & Injury Individual body size & shape (anthropometrics) fitness level / injury history off-work activities psychological status Motivation: injury benefits $$ social

13. Dilbert, by Scott Adams.

14. Performance & Injury Environment physical layout Materials, tools, workstation Work/rest cycles psychological demands The effect of stress to adverse health may be analogous to that of cigarette smoking to lung cancer. While most people who smoke do not get lung cancer, most cases of lung cancer are related to smoking. Kroemer, Kroemer & Kroemer-Elbert, 2001.

15. Performance & Injury Environment Lighting, visual aids Noise

16. ? • FromThe Complexities of Cold • By Ronnie Rittenberry · February 1, 2008 • http://www.ohsonline.com/articles/57758/

17. Example: Working in the Cold • "I can go out and lift a box every day of my life, but then if one day I lift it with four inches of heavy, wet snow on it? It's not the same. And meanwhile I'm wearing protective equipment that decreases the efficiency of my lever systems? And I'm a little bit discombobulated because I'm in a hurry, trying to get out of the cold? This isn't the same box anymore. There's a whole different gorilla sitting inside that box. So I think that's what you look for, is that cold has these multiple effects. It's a risk factor with many variables." • FromThe Complexities of Cold • By Ronnie Rittenberry · February 1, 2008 • http://www.ohsonline.com/articles/57758/

19. Performance & Injury Task KAZIMIR MALEVICH Female reaper 1912The Kustodiev Picture Gallery, Astrakhan

20. At-risk occupations U.S. Bureau of Labor Statistics, 1996 1. Truck driver. 2. Non-construction laborer. 3. Nursing aides and orderlies. 4. Janitors and cleaners. 5. Assemblers. 6. Construction laborers. 7. Carpenters 8. Stock handlers and baggers. 9. Cashiers 10. Cooks 11. Miscellaneous food preparation staff.

21. Illinois, 1999

22. Top 10causesof injury

23. Illinois, 1999

24. Performance & Injury Task Speed of working Complexity of task Fit of components KAZIMIR MALEVICH Female reaper 1912The Kustodiev Picture Gallery, Astrakhan

25. Performance & Injury Individual Task Environment Mismatch predisposes to Injury

26. Nothing is static. Simple model of accident causation. Oborne, 1982.

27. Ergonomics • Psychologists investigate mental function and the workplace • human factors, cognitive factors • Exercise physiologists evaluate metabolic, respiratory & CV effects of prolonged, strenuous activities in industry • work physiology

28. Occupational Biomechanics • Biomechanics • apply laws of physics and engineering concepts to • Describe motion undergone by various body segments • kinematics • Understand the forces acting on these segments • kinetics • Biomechanics • Science concerned with • the mechanical behavior of • the NMS system and component tissues • when physical tasks are performed

29. Who Uses Occupational Biomechanics? YOU Do. Will. • Engineers • Workplace design • Process control • Safety Managers • Allied health providers • Physicians • Nurses • Rehabilitation personnel • PT, OT, AT

30. Techniques of Biomechanics • Kinematics - time and space variables. • Displacement • Velocity • Acceleration • Kinetics - force and energy variables • F = m a • Ft = mVf - mVi • Fd = 1/2 mV2 + mgh

31. Biomechanics Techniques • Kinematics - time and space • Displacement • Velocity • Acceleration • Kinetics - force (torque) & energy • F = m a • Ft = mVf - mVi • Fd = 1/2 mV2 + mgh Demands of the Task & Environment

32. Occupational Biomechanics • complements psychological and physiological knowledge • Considers physical interaction of worker, task & workplace • Basis of OSHA guidelines • Focus is mechanical stress on the body

33. Occupational Biomechanics • complements psychological and physiological knowledge • Considers physical interaction of worker, task & workplace • Basis of OSHA guidelines • Focus is mechanical stress on the body Force / Area

34. Six Methodological Areas Major Application Areas

35. Objectives of Occupational Biomechanics Maximize safety & productivity • Minimize fatigue & overexertion • Improve quality and quantity of output • Minimize time lost to and cost of injury & accident • Minimize absenteeism and labor force turnover Fit the Job to the Worker. Tools, layout, organization, flow

36. Need for Biomechanics Evaluation: • increased complexity of industrial and manufacturing processes • rising costs • health care, rehabilitation, insurance • increase in litigation / bad PR stemming from injury • new legislation (anticipated??) • OSHA 2000 rejected 2001

37. Knowledge of Occupational Biomechanics is used to: • Evaluate physical demands of existing jobs and workplaces • Suggest alternative work methods • scientific principle/basis for change • Facilitate employee selection and placement procedures

38. Social/legal support for occupational biomechanics • Hiring cannot discriminate on basis of • age • race • gender • disability • but jobs must not provide undue risk for injury

39. OSHA Act of 1970 Employers are to provide employees with: • Competent fellow employees & managers • A safe working environment • Knowledge of hazards • Safety rules • Safe tools

40. Implementing a Program Attitude Employee - Self-help Employer - Investment

41. Safety must be accepted as: • Legally necessary • Economically advantageous • Ethically imperative

42. Need for an Occupational Biomechanics Specialty Epidemiological support of occupational biomechanics • Health and quality of life are greatly reduced for many because of musculoskeletal disorders • acute • chronic

43. We want to encourage employers to take the high road to safety - Joseph A. Dear Former OSHA Administrator

45. We want to encourage employers to take the high road to safety and we will use our enforcement program to preclude them from taking the low road. - Joseph A. Dear Former OSHA Administrator

46. Dealing with injury creates a logistical nightmare

48. The Need for an Occupational Biomechanics Specialty • 1990 • 1.8 million disabling work injuries in US • permanent impairment: 600,000 • 72% of injuries of 3 kinds • overexertion (31%) • collision (struck by or striking) (24%) • falls (17%)

49. Event: Sudden Force • Trauma Type: Impact • Typical Medical Outcomes: • Contusion (bruise) • Laceration (cuts) • Sprain (ligament) • Fracture (bone) • Subluxation \ dislocation (joint) • Concussion (brain)

50. Event: Repeated Motion • Trauma Type : Overexertion, overuse injury • RMI: repetitive motion injury • RSI: repetitive strain injury • CTD: cumulative trauma disease • RMD: Repetitive Motion Disorder • OOD: Occupational Overuse Disorder • UECTD: Upper Extremity Cumulative Trauma Disorder • Vibration syndrome