Work-related musculoskeletal disorders (MSDs) cover a broad range of health problems associated with repetitive and strenuous work. These health problems range from discomfort, minor aches, and pains, to more serious medical conditions which can lead to permanent disability. Every year millions of workers are affected by MSDs. The most well-known MSDs are low back pain and work-related upper limb disorders. The first is mainly associated with manual handling while the main risk factors for the latter are associated with task repetition and awkward work postures. Nowadays, lower limb work-related MSDs are also been recognized as disorders that may be associated with the occupational activity.
Work-related MSDs associated with repetitive and strenuous working conditions continue to represent one of the biggest occupational problems in companies. Despite the variety of efforts to control them, including engineering design changes, organizational modifications, and working methods training programs, work-related musculoskeletal disorders account for a huge amount of human suffering and to companies and healthcare systems.
The term work-related MSDs refers to health problems affecting the muscles, tendons, ligaments, cartilage, the vascular system, nerves or other soft tissues & joints of the musculoskeletal system. They are caused or aggravated primarily by work itself and they can affect the upper limb extremities, the neck & shoulders, the lower back area, and the lower limbs.
Work-related MSDs risk factors
The strong correlation between the incidence of MSDs and working conditions is well known, particularly considering the physical risk factors associated with jobs (e.g., awkward postures, high repetition, force exertion, static work, cold or vibration). Work intensification, stress, and other psychosocial factors also seem to be factors that increasingly contribute to the onset of those disorders.
The causes of work-related MSDs are multifactorial and there are numerous work-related risk factors for the various types of MSDs. Several risk factors including physical and mechanical factors, organisational and psychosocial factors, and individual and personal factors may contribute to the genesis of MSDs. Workers are generally exposed to several factors at the same time and the interaction of these effects are often unknown.
Work-related MSDs refer to injuries developed over time that are caused by a combination of risk factors that act simultaneously on a joint or body region, in a synergistic effect. Until now the biological pathogenesis associated with the development of most of the work-related MSDs is unknown. Several models have been proposed to explain the biological mechanisms. Usually, three sets of factors are considered:
Most of the factors can occur both at work and in leisure time activities. Thus, it is important to include all the relevant activities performed both at work and outside work of a specific employee developing MSDs in a working environment.
As referred before, risk factors act simultaneously on a worker joint or body region in a synergistic effect. To manage the risk factors, it is advisable and important to consider this interaction rather than focus on a single risk factor.
Because of high individual variability, it is impossible to estimate the probability of developing work-related MSDs at the individual level. As physicians usually say, “There are no diseases, but patients.”
Types of work-related musculoskeletal disorders
As mentioned before, most of the recorded work-related MSD affect the lower back, neck, shoulders and upper limbs. MSD affects less often on the lower limbs. It is important to recognise, however that not all MSDs are caused by work, although work may provoke symptoms and the problem may prevent a person from working or make it more difficult. For example, a recent study found that age, gender, and BMI made a bigger proportional contribution to developing carpal tunnel syndrome (CTS) than work-related factors.
Work-related upper limb musculoskeletal disorders
Work-related Upper Limb Disorders (WRULDs) can affect any region of the neck, shoulders, arms, forearms, wrists, and hand. Some of WRULDs, such as tendonitis, carpal tunnel syndrome, osteoarthritis, vibration white finger, and thoracic outlet syndrome have well-defined signs and symptoms, while others are less well-defined, involving only pain, discomfort, numbness, and tingling.
However, the designation of WRULDs in international literature is not consensual. In addition to MSDs, other terms are sometimes used referring to similar symptoms and health problems. Examples are:
Despite all the available knowledge, some uncertainty remains about the level of exposure to risk factors that trigger MSDs. In addition, there is significant variability of individual response to the risk factors exposure.
The most common WRULDs are
Low back work-related musculoskeletal disorders
Low back work-related MSDs include spinal disc problems, muscle, and soft tissue injuries. These disorders are mainly associated with physical work, manual handling, and vehicle driving activities, where lifting, twisting, bending, static postures, and whole-body vibration are present.
Work-related Lower Limb Musculoskeletal disorders
Until now little attention has been given to the epidemiology of work-related lower limb MSDs. However, lower limb MSDs are a problem in many workplaces, and they tend to be related to conditions in other areas of the body. Lower Limb Disorders affect the hips, knees, and legs and usually happen because of overuse. Acute injury caused by a violent impact or extreme force is less common. Workers working over a long period in a standing or kneeling position are most at risk. The most common risk factors at work are:
Despite the lack of attention given to this type of work-related MSDs they deserve significant concern since they often give up high degrees of immobility and thereby can substantially degrade the quality of life.
Lower limb work-related MSDs that have been reported in occupational populations are:
However, although these may occur in specific occupational groups (for example Piriformis Syndrome and Trochanteritis have been reported amongst dental personnel; and hamstring strains amongst athletes) the extent to which these have been generally shown to be caused by work is unclear and there are many non-work related factors that can contribute, possibly making the major contribution.
Non-specific work-related musculoskeletal disorders
The non-specific work-related MSD are musculoskeletal disorders that have less well-defined symptoms, i.e. the symptoms tend to be diffuse and non-anatomical, spread over many areas: nerves, tendons and other anatomical structures. The symptoms involve pain (which becomes worse with activity), discomfort, numbness and tingling without evidence of any discrete pathological condition.
Know the symptoms
Pain is the most common symptom of a work-related MSD.
Stiff joints, tight muscles, and redness and swelling of the injured area also may occur, as well as a feeling of “pins and needles.”
MSDs tend to occur in stages:
Early: An employee’s affected limb or body part may feel tired and achy during the work shift, but fine at night or on days off. The worker will not experience a reduction in work performance.s
Middle: The worker’s aching pain and tiredness will start early in his or her shift and persist at night. A reduced capacity for repetitive work likely will occur.
Late: The worker will be tired, weak and achy even when at rest, and may have trouble sleeping or performing light duties.
Not all workers will experience these stages in the same way. However, the earlier a worker recognizes a problem, the quicker he or she should report it and seek treatment.
Dr. Nisha Nair—AVP—Health Risk Consulting
Experienced Healthcare and Wellness specialist with over a decade of experience in corporate health & wellness. Strong consulting professional skilled in Healthcare Management, wellness product development, corporate wellness strategy, client relationship management, wellness services delivery, strategic alliance management, vendor management & Operations Management.