**4. Ergonomics education**

WMSDs through their effect on body structure, function, and posture. Some of the individual-related risk factors are obesity, pregnancy, arthritis, trauma, and endocrinal disorders. Working without rest breaks, binge working, ignoring the body's warning signs such as pain and discomfort, ignoring flexibility/stretching exercises, failing to alternate work tasks, following poor working techniques, and failing to adjust workstation components as needed are

50 Anatomy, Posture, Prevalence, Pain, Treatment and Interventions of Musculoskeletal Disorders

Gender has also been hypothesized as a risk factor. The literature reveals that women are at a relatively higher risk than men [22, 23]. This could be due to differences in anthropometrics and physiology in women. Also, women often assume responsibilities of non–work-related activities such as household tasks, which may add to muscle strain and make them more

Psychological variables such as work pressure and job strain may also contribute to WMSDs. Hannan et al. [24] found a correlation between increased job strain and neck musculoskeletal symptoms. Perceived inadequate support from managers, low level of control, and information overload were also identified as psychosocial risk factors in the literature. With information overload, a worker spends an increasing amount of time using electronic gadgets and ignores proper work posture, thereby developing his/her risk for WMSDs. Mental stress can also augment the physical load during computer work because a computer worker with men-

Working on computers for long hours is a risk factor. The literature reveals a correlation between the duration of computer use and upper extremity (UE) pain, back pain, and eye strain [26]. Repetitive hand, wrist, and finger movements (e.g., typing for extended periods of time), speedy/jerky movements, and force applied while typing may also contribute to UE pain and musculoskeletal discomforts [25]. The demand for productivity and time pressure in today's work culture demand increased keying and extended hours of work from OCWs, thereby making them susceptible to WMSDs. Repetitive motions result in the vasoconstric-

To prevent WMSDs, measures must be taken to avoid exposure to risk factors. These measures could be *technical* such as an elevated work surface for a tall worker, *organizational* such as conducting ergonomic workshops, and/or *personal* such as working with rest breaks [28]. Some of the WMSD prevention strategies in practice include workstation modification, task modification, and provision of necessary ergonomic accessories. However, "for these prevention measures to work, proper knowledge/awareness about how (a) the work-related factors contribute to WMSDs, (b) to carry out the work tasks safely, and (c) to effectively use the equipment, are essential" [13]. Robertson et al. [29] stated that the availability of adjustable office furniture

the examples of some maladaptive work behaviors.

tal stress may exert more force on mouse or keyboard [25].

**2.5. Risk factors associated with duration and intensity of work**

tion of arteries causing ischemic injury and edema due to anoxic damage [27].

**3. Prevention of work-related musculoskeletal disorders**

vulnerable to WMSDs.

**2.4. Psychosocial risk factors**

Ergonomics means the science of fitting the job to the worker. In the context of office computer work, it refers to the computer user-workstation fit. Interventions that aim to enhance this fit are called ergonomic interventions. Ergonomic interventions differ from traditional therapeutic interventions because they target work posture, work habits, behaviors, and the environment [31]. They range from modifying workstations to long-term educational interventions with the aim of preventing and/or treating WMSDs.

Ergonomics is a recognized intervention strategy. Several occupational health and safety agencies across the world advocate for ergonomics. Many mid- and large-size technology companies offer ergonomic training to their employees as ergonomic interventions have been found to enhance productivity, improve worker well-being, and reduce WMSDs.

One of the well-documented ergonomic interventions is ergonomics education [30, 32, 33]. Ergonomics education is a strategy in which an ergonomic expert educates participants (workers) on ergonomic principles [see **Table 2**. Key ergonomic principles] and other necessary ergonomic information either on-site or virtually. The aim is to enhance participants' knowledge on WMSD risk factors, WMSD prevention strategies, and effective work behaviors. There are two primary objectives for any ergonomics education program. One is to help participants become aware of the risk factors and the other is to encourage participants to modify their work behavior.


**Table 2.** Key ergonomic principles.

#### **4.1. Types**

Ergonomics education can be classified into traditional and participatory ergonomics education. In traditional ergonomics education, the information is presented via lectures, seminars, handouts, videos, etc., and participants assume a passive role. In participatory ergonomics education, participants interact with and learn from the expert using adult learning models [34, 35]. The difference between these two types of ergonomics education is the high level of interaction, which is present in the latter. Participatory ergonomics education was reported to achieve better outcomes than the traditional type [36].

contribute to WMSDs. They explain how sustained muscle activity leads to muscle spasms, how back rest angle of less than 95° adds pressure on ischial tuberosities, etc. In addition, they highlight the health issues associated with maladaptive work behaviors such as back pain, visual fatigue, visual dryness (due to constant watching of monitors), headaches, and

The content related to ideal work posture and workstation forms the core of ergonomics education programs for OCWs. The ideal work posture is the one where the back is straight or slightly reclined (95–110°), the shoulders are abducted less than 20°, the elbows are flexed at 90–100°, and the forearm is pronated with the wrist, hand, forearm in a straight line with the work item. Wrist extension or deviation of more than 15° must be avoided. For lower extremities, the legs need to be perpendicular to the floor, the thighs should be parallel to the floor, and the hip joint should be slightly higher than the knee joint. The feet should rest flat on the

According to the US OSHA, an ideal workstation has an adjustable work surface, a keyboard tray, a keyboard and input device (mouse) at the same level and frequently used items placed within easy reach. OSHA recommends a chair with adequate lumbar support, sufficient depth and width to accommodate the user, a seat front with a waterfall edge, and adequate thigh and knee clearance. In an ideal workstation, the top edge of

that the user does not have to bend or extend the neck/head to see and read the monitor (approximately at an arm's length from the user). The monitors are placed perpendicular to the window to minimize glare. An ideal workstation also provides adequate space under the work surface so that the user can get close to the work surface and can cross his/her legs without bumping. It is recommended to leave the area under the desk free of storage. OSHA recommends that all workstation accessories and components be well

Ergonomics education sessions also underscore the importance of work behaviors such as taking adequate rest breaks, engaging in exercise, being mindful of posture, and effectively arranging/adjusting the work surface. It is recommended that computer users take adequate rest breaks and vary their work tasks while working on computers [38]. OSHA recommends rest breaks for jobs that require prolonged posture and repetitive tasks. Henning et al. [39] highlighted the fact that frequent short rest breaks from computermediated work can benefit worker productivity and well-being. Galinsky [40] found that taking four supplemental 5-min rest breaks and two conventional rest breaks of 15 min

Prolonged sitting at work causes biochemical alterations in lipase (an enzyme that metabolizes fat and glucose) activity. These biochemical changes in lipase activity disrupt fat metabolism, which leads to deposits of fats in adipose tissue

rather than being metabolized by muscles and results in weight gain.

The monitor can be positioned a little lower for individuals with bifocals or trifocals.

or slightly below and is placed at a distance from the user so

Ergonomics Education for Office Computer Workers: An Evidence-Based Strategy

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weight gain.2

floor or a footrest.

the monitor lies at eye level3

maintained and serviced.

*4.2.4. Work behaviors*

2

3

*4.2.3. Ideal work posture and workstation*

#### **4.2. Content**

#### *4.2.1. Anatomy and biomechanics*

Ergonomics education programs for computer workers typically include content on biomechanics and anatomy of the back, neck, and upper extremities, as they are the body parts that are commonly affected during office computer work [9, 37]. When reviewing the anatomy and biomechanics of the back, ergonomic experts discuss the anatomy of the spinal curves and biomechanical alterations on the spine and intervertebral discs due to postural modifications. Experts also review the anatomy of two major muscles (trapezius and latissimus dorsi) that get used during office computer work and emphasize how these muscles get stretched or strained when a worker cradles the phone between the neck and shoulder, elevates the shoulders to reach high work surfaces, abducts the shoulders to reach the mouse and/or keyboard, hunches over computers, or reaches overhead to retrieve items.

When reviewing the anatomy of the upper extremities, ergonomic experts place a major emphasis on shoulder joints since awkward shoulder positions contribute significantly to WMSDs related to office computer work. They highlight three most common shoulder positions (elevated shoulders, rounded shoulders, and abducted shoulders) that contribute to UE/neck pain and discomfort. Ergonomic experts also review wrist and hand joints and underscore the importance of keeping wrists in a neutral position while working on computers, as incorrect position of these joints may lead to forearm and wrist pain, discomfort, or injury. Further, they review the impact of repetitive wrist and hand movements on forearm muscles and tendons. Information on conditions like muscle strain and carpal tunnel syndrome1 (a condition that occurs due to increased pressure on the median nerve at wrist) is also presented during these sessions.

#### *4.2.2. Mechanism of injury*

Ergonomics education sessions highlight the mechanism of injury behind WMSDs. It has been a generally accepted notion that the theoretical mechanism behind WMSDs is repetitive microtraumas and their cumulative damage on musculoskeletal tissues. Ergonomic experts educate participants on various risk factors and how they affect musculoskeletal tissues and

<sup>1</sup> Though carpal tunnel syndrome (CTS) is a rare condition among office computer workers, certain conditions such as pregnancy, diabetes, and endocrinal disorders increase the likelihood of sustaining CTS.

contribute to WMSDs. They explain how sustained muscle activity leads to muscle spasms, how back rest angle of less than 95° adds pressure on ischial tuberosities, etc. In addition, they highlight the health issues associated with maladaptive work behaviors such as back pain, visual fatigue, visual dryness (due to constant watching of monitors), headaches, and weight gain.2

#### *4.2.3. Ideal work posture and workstation*

**4.1. Types**

**4.2. Content**

*4.2.1. Anatomy and biomechanics*

Ergonomics education can be classified into traditional and participatory ergonomics education. In traditional ergonomics education, the information is presented via lectures, seminars, handouts, videos, etc., and participants assume a passive role. In participatory ergonomics education, participants interact with and learn from the expert using adult learning models [34, 35]. The difference between these two types of ergonomics education is the high level of interaction, which is present in the latter. Participatory ergonomics education was reported to

Ergonomics education programs for computer workers typically include content on biomechanics and anatomy of the back, neck, and upper extremities, as they are the body parts that are commonly affected during office computer work [9, 37]. When reviewing the anatomy and biomechanics of the back, ergonomic experts discuss the anatomy of the spinal curves and biomechanical alterations on the spine and intervertebral discs due to postural modifications. Experts also review the anatomy of two major muscles (trapezius and latissimus dorsi) that get used during office computer work and emphasize how these muscles get stretched or strained when a worker cradles the phone between the neck and shoulder, elevates the shoulders to reach high work surfaces, abducts the shoulders to reach the mouse and/or keyboard,

When reviewing the anatomy of the upper extremities, ergonomic experts place a major emphasis on shoulder joints since awkward shoulder positions contribute significantly to WMSDs related to office computer work. They highlight three most common shoulder positions (elevated shoulders, rounded shoulders, and abducted shoulders) that contribute to UE/neck pain and discomfort. Ergonomic experts also review wrist and hand joints and underscore the importance of keeping wrists in a neutral position while working on computers, as incorrect position of these joints may lead to forearm and wrist pain, discomfort, or injury. Further, they review the impact of repetitive wrist and hand movements on forearm muscles and tendons. Information on con-

Ergonomics education sessions highlight the mechanism of injury behind WMSDs. It has been a generally accepted notion that the theoretical mechanism behind WMSDs is repetitive microtraumas and their cumulative damage on musculoskeletal tissues. Ergonomic experts educate participants on various risk factors and how they affect musculoskeletal tissues and

Though carpal tunnel syndrome (CTS) is a rare condition among office computer workers, certain conditions such as

(a condition that occurs due to increased

achieve better outcomes than the traditional type [36].

52 Anatomy, Posture, Prevalence, Pain, Treatment and Interventions of Musculoskeletal Disorders

hunches over computers, or reaches overhead to retrieve items.

ditions like muscle strain and carpal tunnel syndrome1

*4.2.2. Mechanism of injury*

1

pressure on the median nerve at wrist) is also presented during these sessions.

pregnancy, diabetes, and endocrinal disorders increase the likelihood of sustaining CTS.

The content related to ideal work posture and workstation forms the core of ergonomics education programs for OCWs. The ideal work posture is the one where the back is straight or slightly reclined (95–110°), the shoulders are abducted less than 20°, the elbows are flexed at 90–100°, and the forearm is pronated with the wrist, hand, forearm in a straight line with the work item. Wrist extension or deviation of more than 15° must be avoided. For lower extremities, the legs need to be perpendicular to the floor, the thighs should be parallel to the floor, and the hip joint should be slightly higher than the knee joint. The feet should rest flat on the floor or a footrest.

According to the US OSHA, an ideal workstation has an adjustable work surface, a keyboard tray, a keyboard and input device (mouse) at the same level and frequently used items placed within easy reach. OSHA recommends a chair with adequate lumbar support, sufficient depth and width to accommodate the user, a seat front with a waterfall edge, and adequate thigh and knee clearance. In an ideal workstation, the top edge of the monitor lies at eye level3 or slightly below and is placed at a distance from the user so that the user does not have to bend or extend the neck/head to see and read the monitor (approximately at an arm's length from the user). The monitors are placed perpendicular to the window to minimize glare. An ideal workstation also provides adequate space under the work surface so that the user can get close to the work surface and can cross his/her legs without bumping. It is recommended to leave the area under the desk free of storage. OSHA recommends that all workstation accessories and components be well maintained and serviced.

#### *4.2.4. Work behaviors*

Ergonomics education sessions also underscore the importance of work behaviors such as taking adequate rest breaks, engaging in exercise, being mindful of posture, and effectively arranging/adjusting the work surface. It is recommended that computer users take adequate rest breaks and vary their work tasks while working on computers [38]. OSHA recommends rest breaks for jobs that require prolonged posture and repetitive tasks. Henning et al. [39] highlighted the fact that frequent short rest breaks from computermediated work can benefit worker productivity and well-being. Galinsky [40] found that taking four supplemental 5-min rest breaks and two conventional rest breaks of 15 min

<sup>2</sup> Prolonged sitting at work causes biochemical alterations in lipase (an enzyme that metabolizes fat and glucose) activity. These biochemical changes in lipase activity disrupt fat metabolism, which leads to deposits of fats in adipose tissue rather than being metabolized by muscles and results in weight gain.

<sup>3</sup> The monitor can be positioned a little lower for individuals with bifocals or trifocals.


**Table 3.** Stretching exercise guidelines.

throughout the work day can minimize discomfort without impairing productivity. Microbreaks at 20-min intervals were also reported to be effective [8]. During rest breaks, it is wise to step away from the workstation and walk around. Workers may visit a colleague's office, go to the print room, use the restroom or cafeteria, etc. To reduce eye discomfort and dryness, ergonomic experts recommend taking microbreaks to look 20 feet away from the monitor.

imaginary line that connects the ears, shoulders, and hip joints and advise to maintain the line. Ergonomic experts also show participants examples of good (ideal posture) and bad posture (slouching, keeping feet on chair frame, elevating shoulders, etc.) during ergonom-

Ergonomics Education for Office Computer Workers: An Evidence-Based Strategy

http://dx.doi.org/10.5772/intechopen.72221

55

When delivering ergonomics education, experts emphasize that ergonomics is nothing but a fit between worker and work environment. They offer information on arranging the workstation and adjusting its components. They suggest that computer workers keep work items within reach. It is generally recommended to keep frequently used items within forearm reach and less frequently used items within arm's reach. During ergonomics education sessions, experts show participants how to adjust manual and pneumatic office chairs in addition to other workstation components. When teaching chair adjustment, the emphasis is on properly adjusting the backrest because backrests that are tilted too far forward or backward

The problems associated with poor office chairs (fixed backrests/arm rests, too low or too high, too wide or too narrow, and sharp edges), poor workstations (sharp edges), and poor work environments (bad lighting, glare, hot/cold environments) are reviewed during ergo-

During ergonomics education sessions, ergonomic experts review various ergonomic accessories and their uses. Keyboard trays, footrests, glare protectors, document holders, large size mouse, hands-free telephones are some of the common accessories that are reviewed. According to ergonomic experts, there is no manufactured ergonomic device because what could be an ergonomically suitable device for a computer worker may not be suitable for another worker due to variations in anthropometric characteristics, nature of work tasks, and

Ergonomics education is delivered to computer workers through didactic lectures, PowerPoint presentations, discussions, demonstrations, video, workstation visits, one-to-one consulta-

Ergonomic checklists, session handouts, brochures, and pictures of ideal work postures and workstations are some of the commonly provided materials at ergonomics education sessions. Product manuals are also used as ergonomics education tools. These manuals describe

the product's features/specifications and how to use/operate the product.

ics education sessions.

may contribute to back issues.

nomics education sessions.

*4.2.6. Ergonomic accessories*

workstation arrangements.

tions, provision of resources, etc.

**4.3. Mode of delivery**

**4.4. Materials**

*4.2.5. Ergonomic workstation issues*

Ergonomic experts recommend that computer workers exercise at work [41], as the postural and proximal UE muscles undergo static loading during office computer work. They suggest that computer workers engage in stretching and flexibility exercises. Stretching exercises break cumulative musculoskeletal strain and relieve intervertebral disc pressure. Evidence supports the use of exercise to reduce musculoskeletal discomfort for computer workers [42]. By engaging in exercises, OCWs can reduce perceived discomfort [43], improve posture [44], and minimize fatigue [45]. Neck stretch, neck tilt, chin tuck, side stretch, and torso twist are some recommended exercises for the neck and upper body. Shoulder shrugs and rotations, wrist circles, and stretching the wrist flexors/extensors are some recommended exercises for the upper extremities. Hip marching, leg hug, leg extension, and ankle pumps are some of the exercises for the lower body.4 Stretching exercises also have psychological benefits. Stretching increases mental alertness while decreasing anxiety and stress [46]. **Table 3** presents the stretching exercise guidelines [**Table 3**. Stretching exercise guidelines].

In office work environments, workers start the work day with good posture, but eventually recline or bend throughout the course of the day assuming risky postures and enhancing their risk for WMSDs [47]. Some workers habitually cradle the phone between the neck and shoulder so that their hands are free to type on the keyboard, thereby adding stress and strain to the lateral supporting muscles. Hence, ergonomic experts advise computer workers to be mindful of their posture when performing computer work. To help computer workers to be mindful of their posture, ergonomic experts suggest them to draw an

<sup>4</sup> It is critical to consult an ergonomics specialist, occupational therapist, physical therapist, physician, or other healthcare provider before engaging in any of the listed exercises or beginning an exercise regime. These exercises should not be considered complete or exhaustive and should not be used for self-treatment.

imaginary line that connects the ears, shoulders, and hip joints and advise to maintain the line. Ergonomic experts also show participants examples of good (ideal posture) and bad posture (slouching, keeping feet on chair frame, elevating shoulders, etc.) during ergonomics education sessions.

When delivering ergonomics education, experts emphasize that ergonomics is nothing but a fit between worker and work environment. They offer information on arranging the workstation and adjusting its components. They suggest that computer workers keep work items within reach. It is generally recommended to keep frequently used items within forearm reach and less frequently used items within arm's reach. During ergonomics education sessions, experts show participants how to adjust manual and pneumatic office chairs in addition to other workstation components. When teaching chair adjustment, the emphasis is on properly adjusting the backrest because backrests that are tilted too far forward or backward may contribute to back issues.

#### *4.2.5. Ergonomic workstation issues*

throughout the work day can minimize discomfort without impairing productivity. Microbreaks at 20-min intervals were also reported to be effective [8]. During rest breaks, it is wise to step away from the workstation and walk around. Workers may visit a colleague's office, go to the print room, use the restroom or cafeteria, etc. To reduce eye discomfort and dryness, ergonomic experts recommend taking microbreaks to look 20 feet

• Repeat each stretching exercise 10 times or at least 3–4 times during each episode of exercise [43].

54 Anatomy, Posture, Prevalence, Pain, Treatment and Interventions of Musculoskeletal Disorders

Ergonomic experts recommend that computer workers exercise at work [41], as the postural and proximal UE muscles undergo static loading during office computer work. They suggest that computer workers engage in stretching and flexibility exercises. Stretching exercises break cumulative musculoskeletal strain and relieve intervertebral disc pressure. Evidence supports the use of exercise to reduce musculoskeletal discomfort for computer workers [42]. By engaging in exercises, OCWs can reduce perceived discomfort [43], improve posture [44], and minimize fatigue [45]. Neck stretch, neck tilt, chin tuck, side stretch, and torso twist are some recommended exercises for the neck and upper body. Shoulder shrugs and rotations, wrist circles, and stretching the wrist flexors/extensors are some recommended exercises for the upper extremities. Hip marching, leg hug, leg

cises also have psychological benefits. Stretching increases mental alertness while decreasing anxiety and stress [46]. **Table 3** presents the stretching exercise guidelines [**Table 3**.

In office work environments, workers start the work day with good posture, but eventually recline or bend throughout the course of the day assuming risky postures and enhancing their risk for WMSDs [47]. Some workers habitually cradle the phone between the neck and shoulder so that their hands are free to type on the keyboard, thereby adding stress and strain to the lateral supporting muscles. Hence, ergonomic experts advise computer workers to be mindful of their posture when performing computer work. To help computer workers to be mindful of their posture, ergonomic experts suggest them to draw an

It is critical to consult an ergonomics specialist, occupational therapist, physical therapist, physician, or other healthcare provider before engaging in any of the listed exercises or beginning an exercise regime. These exercises should not be

Stretching exer-

extension, and ankle pumps are some of the exercises for the lower body.4

considered complete or exhaustive and should not be used for self-treatment.

away from the monitor.

• Stretch the muscles slowly and avoid jerky movements [53].

• Stretch only to the point of comfortable stretch.

• Breathe slow, deep, and rhythmic while stretching.

• Hold the stretch for 5-20 seconds.

**Table 3.** Stretching exercise guidelines.

• Feel the stretch.

Stretching exercise guidelines].

4

The problems associated with poor office chairs (fixed backrests/arm rests, too low or too high, too wide or too narrow, and sharp edges), poor workstations (sharp edges), and poor work environments (bad lighting, glare, hot/cold environments) are reviewed during ergonomics education sessions.

#### *4.2.6. Ergonomic accessories*

During ergonomics education sessions, ergonomic experts review various ergonomic accessories and their uses. Keyboard trays, footrests, glare protectors, document holders, large size mouse, hands-free telephones are some of the common accessories that are reviewed. According to ergonomic experts, there is no manufactured ergonomic device because what could be an ergonomically suitable device for a computer worker may not be suitable for another worker due to variations in anthropometric characteristics, nature of work tasks, and workstation arrangements.

#### **4.3. Mode of delivery**

Ergonomics education is delivered to computer workers through didactic lectures, PowerPoint presentations, discussions, demonstrations, video, workstation visits, one-to-one consultations, provision of resources, etc.

#### **4.4. Materials**

Ergonomic checklists, session handouts, brochures, and pictures of ideal work postures and workstations are some of the commonly provided materials at ergonomics education sessions. Product manuals are also used as ergonomics education tools. These manuals describe the product's features/specifications and how to use/operate the product.
