HUMAN FACTOR: Introduction To Ergonomics - DR K.M. ANNAMALAI

What is the ultimate goal of our work?  Marx would say our efforts go towards making a few people richer, while the rest of us waste our lives doing hard work we hate, just to survive.  It is certainly hard to argue the point that technology makes our lives easier, because we still work just as hard to control the machines we designed to “do the work for us.” In this section, I would like to provide you explanations, guidelines and suggestions on how to work smarter not harder and to have more energy left at the end of the day, through the techniques of one of the most coveted topics in PT today, i.e. Ergonomics. Today’s work environment has changed significantly over the past few decades. Our jobs today are much safer but the work has changed specifically in the office. Years ago people might have carried out tasks using many muscles in variety of positions. Today’s jobs are much more specialized. Today’s office is filled with special work like word processing, accounting, telemarketing, data entry and others. This job requires holding a sustained position all day, while repeating the same task over and over again. Many jobs require us to focus for the entire day on one or two sets of muscles held in the same position all day long. This is a very hard work and it can leads to excesses fatigue, pain and even an injury.

People would expect you as a physiotherapist, to help them alleviate the pain and suffering that occurs as a result of the work life that they have. Through this section we shall have a series of articles that shall provide you an outline on how Ergonomic advises to your patients can become a part of your daily practice and a good source of your income. Bernardino Ramazzini, and Italian physician and philosopher, Who is considered the founder of occupational medicine (or ergonomics) realized that a variety of common workers’ diseases appeared to be caused by prolonged irregular motions and postures. In 1700 Ramazzini published De morbis artificum diatriba (Diseases of Workers), the first comprehensive work on occupational diseases. He studied the relationship between certain disorders and postural attitudes, repetition of movements, and weight lifting and anticipated some preventive measures.It seems like ergonomists have been giving basically the same advice for 300 years. Occupational injury and disease has existed since the beginnings of “work” as we understand it today, (agriculture, organized labor and mass production) and is caused by the same basic problem…repetitive, unnatural motion without breaks.

Ergonomics is the science of work. Ergonomics derives from two Greek words: ergo, meaning work, and nomoi, meaning natural laws. Combined they create a word that means the science of work and a person’s relationship to that work. It is also known as Human Factors, Human Engineering, Human Factors Engineering, Man-Machine Interface. To explain the word interface with example: A typical computer station will have four human-machine interfaces, the keyboard (hand), the mouse (hand), the monitor (eyes) and the speakers (ears). Ergonomics studies work as it relates to the human body and its limits. The usual goal is maximum output without physical harm,Physiology, biomechanics, anthropometrics, worker selection and man-machine allocation are the areas of ergonomics. The most prevalent ergonomic related injuries are musculoskeletal; either from repetition, overload, awkward positions or some combination thereof. An objective of the ergonomics approach is to obtain an effective match between the user and the work system and one in which there is optimization of: safety, comfort, ease of use, productivity/performance, and aesthetics. In addition, International Ergonomics Association (IEA) divides ergonomics into three domains: 1) Physical ergonomics - concerned with human anatomical, anthropometric, physiological and biomechanical characteristics as they relate to physical activity 2) Cognitive ergonomics - concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system 3) Organizational ergonomics - concerned with the optimization of sociotechnical systems, including their organizational structures, policies, and processes.

During the ergonomic process, problems are gradually worked out and brought to a solution. Problems may be similar but the contexts in which they appear are almost unique. Thus, the ergonomic process will hardly ever be the same, and experiences gained in one case cannot be applied mechanically to another place. Furthermore, there is very seldom only one possible solution, but many and probably quite different ones, depending on the culture and awareness at the work place, its size and level of technology, and the human and financial resources available.

Moreover, the chosen solution must comply with the aims of the organization which again influences the choice of solution. The ergonomic process in practice will consequently take different ways and differ considerably from time to time. However, some important steps or phases in the process can be traced in most cases and need to be handled for a successful outcome. These phases are:1) Organization of process 2) Identifying the problem 3) Analyzing the problem 4) Developing a solution 5) Implementing the solution 6) Evaluation of the result (Ergonomic Analysis)

Basic principal:  To increase the work out put with quality and quantity in a limited time period with less effort or input.

How does Body work?: Sitting in one position at work station requires very stressful muscle work. Musculoskeletal system is that part of the body which does the physical work. The musculoskeletal system works very hard for you all day with two types of work. First type is the most obvious movement. The second type is not so obvious posture. Standing, even for a short time, proves so exhausting as compared to walking and running for a long time. It is generally supposed that this is because of the tonic movement of all the antagonist muscles, both extensors and flexors, which have to be continually in action to enable a man to keep standing erect. It follows that whenever occasion offers, we must advise men employed in the standing trades to interrupt too prolonged standing posture by sitting or walking about or exercising the body in some way. Even standing with a neutral posture for long periods of time is unhealthy. Where it cannot be avoided, anti-fatigue mats should be placed underfoot. Users should sit down for a few minutes regularly, shift positions frequently, or, while standing, rest one foot on a stool or curb. Those who sit at their work and are therefore called “chair-workers,” such as cobblers and tailors become bent, hump-backed, and hold their heads down like people looking for something on the ground; this is the effect of their sedentary life and the bent posture of the body as they sit and apply themselves all day to their tasks in the shops where they sew. Since to do their work they are forced to stoop, the outermost vertebral ligaments are kept pulled apart and contract a callosity, so that it becomes impossible for them to return to the natural position. These workers, then, suffer from general ill-health caused by their sedentary life.

The maladies that afflict the clerks arise from three causes: First, constant sitting, secondly the incessant movement of the hand and always in the same directions. Incessant driving of the pen over paper causes intense fatigue of the hand and the whole arm because of the continuous and almost tonic strain on the muscles and tendons, which in course of time results in failure of power in the right hand. All sedentary workers suffer from lumbago. They should be advised to take physical exercise, at any rate on holidays. Let them make the best use they can of [exercise] one day, and so to some extent counteract the harm done by many days of sedentary life. Therefore in work so taxing, moderation would be the best safeguard against these maladies, for men and women alike; for the common maxim “Nothing to excess” is one that I excessively approve. The evolution of industry and technology has brought with it only further enslavement of the worker to our own machinery. Although working conditions have definitely improved in the last 100 years, I would say today’s workers (both manual laborers or office jockies) tax their bodies just as much as ever.

OOS / RSI / MSD / CTS / CVS: OOS (Occupational Overuse Syndrome) is also known as RSI (Repetitive Strain Injury - USA) and MSD (Musculoskeletal Disorders - Europe). CTS (Carpal Tunnel Syndrome) and CVS (Computer vision syndrome) also are associated with computer use.These injuries are becoming more and more common in today's computer intensive world. OOS, RSI, MSD, CTS and CVS can become very painful and debilitating if not treated early. With this in mind, the best cure is prevention. If injuries already exist, strict work methods are required to facilitate recovery.  Break Reminder is designed to both prevent and assist convalescence of these debilitating computer terminal associated conditions. It has numerous other benefits also. Whilst we have many anecdotal reports of the value of this software, there is also research that supports the value this type of software provides to PC users. Break Reminder has a small program interface that discretely runs in the background. It can monitor your computer use, and reminds (or can force) you to take a break to user chosen settings.

Who can be the ergonomist?: Any individual interested to work smart ADL (activity of daily living), occupational therapist, physical therapist, bio-mechanist, safety engineers, architects, psychiatrist, etc

What are the fields of applications we are going to see in the forthcoming journey of this section?: Clerical, agriculture, software, industrial, healthcare, academic, research, public sector, housewives, youth, geriatrics, school children, vehicle, emotional, footwear, during illness and disease, urinary, ophthalmic, space , etc I will be in touch with you a lot more in the issues. Hope to see you all working Smarter….




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