Document ID: OSHA-2009-0044-0004
Agency: osha
Document Type: Supporting & Related Material
Title: 
Posted Date: 2010-02-01T05:00Z

Alternative Definitions of MSDs

Work-related musculoskeletal disorders (WMSDs) have been studied for
several years, and different terminology has been used to describe this
broad class of occupational injuries and illnesses. Among others, the
following terms were applied: cumulative trauma disorder (CTD),
repetitive motion injury (RMI), repetitive strain injury (RSI),
occupational overuse syndrome (OOS), occupational cervicobrachial
disease (OCD), occupational overexertion syndrome (OES), and ergonomics
injury.  Similarly, multiple definitions of WMSD have been used for
specific purposes by different organizations, and these definitions
varied even within organizations.  

However, all of these definitions had a common goal, to aggregate a
broad class of injuries and illnesses into a single category for the
purpose of assessment of injury and illness related to work exposure to
ergonomic risk factors. Most of the definitions used the general
description and the examples of specific types of injuries and illnesses
were often added to delineate MSDs from other types of disorders.  

OSHA has identified a number of definitions that have been used for
various purposes by different organizations and agencies:

 

American National Standard, ANSI/ASSE A10.40-2007; Reduction of
Musculoskeletal Problems in Construction; American National Standard for
Construction and Demolition Operations.

“Musculoskeletal Problems. Musculoskeletal Problems include injuries
to the muscle, tendons, sheath, nerve, bursa, blood vessel, bone, joint,
or ligament and musculoskeletal pain or swelling, and also where there
may not be any obvious evidence of injury, and where occupational
exposure is clearly identified. The injuries include, but are not
limited to:

Muscular

Carpal Tunnel Syndrome

Thoracic Outlet

Tenosynovitis

Myalgia

Double Crush Syndrome

Reynaud’s 

De Quervains

Strains

Cubital Tunnel Syndrome

Connective Tissue

Brusitis

Spasms

Sciatica

Disc Damage

Neurological

Vascular

Tendonitis

Back”

****

NIOSH Elements of Ergonomics Programs. A Primer Based on Workplace
Evaluations of Musculoskeletal Disorders. U.S. Department of Health and
Human Services, Public Health Service, Center for Disease Control and
Prevention, National Institute for Occupational Safety and Health, 1997

Although definitions vary, the general term "musculoskeletal disorders"
describes the following: 

Disorders of the muscles, nerves, tendons, ligaments, joints, cartilage,
or spinal discs 

Disorders that are not typically the result of any instantaneous or
acute event (such as a slip, trip, or fall) but reflect a more gradual
or chronic development (nevertheless, acute events such as slips and
trips are very common causes of musculoskeletal problems such as low
back pain) 

Disorders diagnosed by a medical history, physical examination, or other
medical tests that can range in severity from mild and intermittent to
debilitating and chronic 

Disorders with several distinct features (such as carpal tunnel
syndrome) as well as disorders defined primarily by the location of the
pain (i.e., low back pain) 

The term "WMSDs" refers to (1) musculoskeletal disorders to which the
work environment and the performance of work contribute significantly,
or (2) musculoskeletal disorders that are made worse or longer lasting
by work conditions. These workplace risk factors, along with personal
characteristics (e.g., physical limitations or existing health problems)
and societal factors, are thought to contribute to the development of
WMSDs [Armstrong et al. 1993]. They also reduce worker productivity or
cause worker dissatisfaction. Common examples are jobs requiring
repetitive, forceful, or prolonged exertions of the hands; frequent or
heavy lifting, pushing, pulling, or carrying of heavy objects; and
prolonged awkward postures. Vibration and cold may add risk to these
work conditions. Jobs or working conditions presenting multiple risk
factors will have a higher probability of causing a musculoskeletal
problem. The level of risk depends on the intensity, frequency, and
duration of the exposure to these conditions and the individual’s
capacity to meet the force or other job demands that might be involved.
These conditions are more correctly called "ergonomic risk factors for
musculoskeletal disorders" rather than "ergonomic hazards" or "ergonomic
problems." But like the term "safety hazard," these terms have popular
acceptance.

Musculoskeletal disorders (MSDs) are a group of injuries that affect one
or more parts of the musculoskeletal system such as muscles, tendons,
joints, cartilage, spinal discs, ligaments, and nerves.  Common
injuries associated with MSDs include sprains and strains of the back,
neck, shoulders, wrists and fingers.  MSDs can cause temporary or
permanent disability and typically develop from overexertion or
gradually over time.  [Sources: NIOSH, 1997; Cal/OSHA, 1999]    MSDs
are also known as repetitive strain injuries, cumulative or repeated
trauma disorders, repetitive motion injuries, and professional overuse
syndromes. [Sources: Cal/OSHA, 1999; NOHSC, 1996]  Work-related MSDs
may occur in tasks with activities that overexert the body, for example
when lifting residents in a nursing home, cutting wire bands from
bundles, or frequently clicking a computer mouse. 

					***

The World Health Organization - definition of MSD:

“The term musculoskeletal disorders denotes health problems of the
locomotor apparatus, i.e. of muscles, tendons, the skeleton, cartilage,
ligaments and nerves. Musculoskeletal disorders include all forms of
ill-health ranging from light, transitory disorders to irreversible,
disabling injuries.”  

(Protecting Workers’ Health Series No.5; Preventing musculoskeletal
disorders in the workplace. 2003 World Health Organization)

				****

The American Academy of Orthopaedic Surgeons (AAOS)  

Position Statement 1165  © December 2004 American Academy of
Orthopaedic Surgeons

This material may not be modified without the express written permission
of the American Academy of Orthopaedic Surgeons®.

Defining Musculoskeletal Disorders in the Workplace

This Position Statement was developed as an educational tool based on
the opinion of the authors. It is not a product of a systematic review.
Readers are encouraged to consider the information presented and reach
their own conclusions.

The term musculoskeletal disorder (MSD) is commonly used as a catch-all
phrase to refer to a variety of diseases or injuries to bones, muscles,
tendons, joints, nerves and blood vessels that may occur in the
workplace. Grouping these divergent pathologies into a single term can
create confusion and muddle thinking among employers, employees,
healthcare providers, insurers, and policymakers that must address
workers’ compensation and ergonomics issues. To illustrate this point,
the 2001 report from the National Academy of Science and the Institute
of Medicine, “Musculoskeletal Disorders and the Workplace,” defines
MSD no more specifically than the “loss of the sense of well being in
a body part.” 

Other vague catch-all terms used to describe diseases and injuries that
may occur in the workplace include: cumulative trauma disorder,
repetitive stress disorder, repetitive stress injury, and work-related
disorder.

Use of these unclear terms can lead to erroneous assumptions and
conclusions about pathologies that may occur in the workplace. For
example, employers and employees sometimes mistakenly believe that the
causes for all of the pathologies that fall within the “definition”
of MSD are the same, when in fact the causes of these various
pathologies might be quite different.

The term MSD, as well as other non-specific phrases, should not be used
as a clinical diagnosis in scientific literature or regulatory language
because they are vague terms and subject to misinterpretation. Instead,
stakeholders in the workers’ compensation and ergonomics arena should
use precise terminology to describe pathologies that may occur in the
workplace. This allows researchers and scientists to develop reliable
scientific evidence for clearly defined pathologies, which in turn
allows policymakers to formulate regulations based on sound scientific
evidence. Ultimately, this clarity will improve the quality of care
provided to injured workers and reduce overall healthcare costs within
the workers’ compensation system.

The American Academy of Orthopaedic Surgeons (AAOS) believes
“musculoskeletal disorder” and other non-specific phrases should not
be used as a clinical diagnosis because these terms are vague and
confusing and do not appropriately describe diseases and injuries that
may occur in the workplace.

The World Health Organization created a reporting system known as the
International Classification of Diseases (ICD) that provides much more
specific descriptions of various illnesses, injuries, and diseases. ICD
was developed as a method to report and collect data on illnesses,
injuries, and diseases. This reporting system uses precise criteria for
clinical diagnoses and is widely accepted across the United States and
internationally. 

Low back pain, carpal tunnel syndrome, trigger finger, lateral
epicondylitis, tendonitis, and bursitis are common medical conditions
that have been described as MSDs. However, all of these conditions have
existing ICD codes that should be used instead of the term MSD so that
there is a more clear understanding of the pathologic process and so
that communication among employers, employees, healthcare providers,
insurers, researchers, and regulators are more consistent and
scientific. 

The AAOS believes ICD diagnosis codes should be used instead of
“musculoskeletal disorder” and other non-specific terms when
describing and reporting pathologies that may occur in the workplace.

				****

The National Academies: National Academy of Science, National Academy of
Engineering, Institute of Medicine, and National Research Council

National Research Council and Institute of Medicine (2001)
Musculoskeletal Disorders and the Workplace: Low Back and Upper
Extremities. Panel on Musculoskeletal Disorders and the Workplace.
Commission on Behavioral and Social Sciences and Education. Washington,
DC: National Academy Press.  pp. 37

“Work-Related Illness or Disease: Work-Related Illness or Disease may
be caused by, aggravated, accelerated, or exacerbated by workplace
exposures, and they may impair working capacity. Personal
characteristics and other environmental and sociocultural factors
usually play a role as risk factors in work-related illnesses and
diseases.

Occupational diseases are at one end of the work relatedness spectrum,
where the relationship to specific causal factors at work has been fully
established and the factors concerned can be identified, measured, and
eventually controlled. At the other end of the spectrum are diseases
with a weak, inconsistent, unclear relationship to working conditions;
and in the middle of spectrum there is a possible causal relationship,
but the strength and magnitude of it may vary.]  (from World Health
Organization, 1985).- This definition also includes conditions that are
not caused by work, but which are aggravated at work.

				****

BLS definition: 

“Musculoskeletal Disorders (MSDs) include cases where the nature of
the injury is sprains; strains; tears; back pain; hurt back; soreness;
pain; hurt; except the back; carpal tunnel syndrome; hernia; or
musculoskeletal system and connective tissue diseases and disorders,
when the event or exposure leading to the injury or illness is bodily
reaction/bending, climbing, crawling, reaching, twisting, overexertion,
or repetition.  Cases of Raynaud’s phenomenon, tarsal tunnel syndrome,
and herniated spinal discs are not included, although they may be
considered MSDs, the survey classifies these injuries and illnesses in
categories that also include non MSD cases.

					****

Definition from the 2000 ergonomics standard overturned by Congress:

“a disorder of the muscles, nerves, tendons, ligaments, joints,
cartilage, blood vessels, or spinal disks.  For purposes of this
standard, this definition only includes MSDs in the following areas of
the body that have been associated with exposure to risk factors; neck,
shoulder, elbow, forearm, wrist, hand, abdomen (hernia only), back,
knee, anakle, and foot.  MSDs may include muscle strains and tears,
ligament sprains, joint and tendon inflammation, pinched nerves, and
spinal disc degeneration.  MMSDs include such medical conditions as: low
back pain, tension neck syndrome, carpal tunnel syndrome, rotator cuff
syndrome, DeQuervain’s syndrome, trigger finger, tarsal tunnel
syndrome, sciatica, epicondylitis, tendonitis, Raynaud’s phenomenon,
hand-arm vibration syndrome (HAVS), carpet layer’s knee, and herniated
spinal disc.  Injuries arising from slips, trips, falls, moor vehicle
accidents, or similar accidents are not considered MSDs for the purposes
of this standard. 

				****

Definition from the 2001 Recordkeeping rule:

Musculoskeletal disorders (MSDs) are disorders of the muscles, nerves,
tendons, ligaments, joints, cartilage and spinal discs. MSDs do not
include disorders caused by slips, trips, falls, motor vehicle
accidents, or other similar accidents. Examples of MSDs include: Carpal
tunnel syndrome, Rotator cuff syndrome, De Quervain's disease, Trigger
finger, Tarsal tunnel syndrome, Sciatica, Epicondylitis, Tendinitis,
Raynaud's phenomenon, Carpet layers knee, Herniated spinal disc, and Low
back pain.

				****

Navy Occupational Safety and Health Program Manual; OPNAVINST 5100.23G;
NO9F 30 Dec 2005 

WMSDs are defined as a class of disorders involving damage to muscles,
tendons, tendon sheaths, and related bones, and nerves.  They may also 
be known more specifically as repetitive strain injuries (RSI);
Cumulative Trauma Disorders (CTDs) and Overuse Syndrome.  WMSDs result
from the cumulative effect of repeated traumas associated with specific
workplace risk factors.  Risk factors include but are not limited to:  

 

  (1) Force - the amount of physical effort required to maintain control
of equipment or tools or perform a task such as heavy lifting, pushing,
pulling, grasping, or carrying.

  (2) Repetition - performing the same motion or series of motions
continually 

or frequently for an extended period of time with little variation. 
Examples include prolonged typing, assembling components and repetitive
hand tool usage. 

 

  (3) Awkward or static postures - awkward posture refers to positions
of the body (limbs, joints, back) that deviate significantly from the
neutral position while performing job tasks.  For example, overhead
work, extended reaching, twisting, and squatting or kneeling.  

Static postures refer to holding a fixed position or posture.  Examples
include gripping tools that cannot be set down or standing in one place
for prolonged periods. 

 

  (4) Vibration - Localized vibration, such as vibration of the hand and
arm, occurs when a specific part of the body comes into contact with
vibrating objects such as powered hand tools (e.g., chain saw, electric
drill, chipping hammer) or equipment (e.g., wood planer, punch press,
packaging machine).  Whole-body vibration occurs when standing or
sitting in vibrating environments (e.g., operating a pile driver or
driving a truck over bumpy roads) or when using heavy vibrating
equipment that requires whole-body involvement (e.g., jackhammers). 

 

  (5) Contact stress - results from occasional, repeated or continuous
contact between sensitive body tissues and a hard or sharp object. 
Examples include resting the wrist on a hard desk edge, tool handles
that press into the palms or using the hand as a hammer. 

 

When present for sufficient duration, frequency, magnitude, or in
combination, these risk factors may cause WMSDs.  In addition, personal
risk factors, such as, physical conditioning, existing health problems,
gender, age, work technique, hobbies and organizational factors (e.g.
job autonomy, quotas, deadlines) contribute to the development of WMSDs.
Additionally, environmental conditions such as working in temperature
extremes may contribute to the development of WMSDs. 

		

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