Work-Related Musculoskeletal Disorders (WMSDs): Causes, Symptoms, Statistics and Prevention

What are work-related musculoskeletal disorders?

Musculoskeletal disorders (MSDs) are, in NIOSH's words, disorders of the muscles, nerves, tendons, ligaments, joints, cartilage or spinal discs. Work-related musculoskeletal disorders (WMSDs) are MSDs that can be attributed to the work environment and the performance of work.

The key point for employers is that WMSDs are mostly about exposure over time. For desk-based upper-limb symptoms, see our guide to RSI symptoms and prevention. CCOHS explains that ordinary movements like bending, gripping, twisting and reaching aren't harmful in daily life. What makes them hazardous at work is continual repetition, often with force, at speed, and without time to recover.

This article is general information, not medical advice. If you have persistent pain, numbness or tingling, see a clinician.

If you're responsible for a workplace, the fastest way to start is to screen jobs for risk factors. Our free ergonomic assessment checklist is built around the factors described below.

What are common examples of WMSDs?

OSHA lists these examples:

• Carpal tunnel syndrome
• Tendinitis
• Rotator cuff injuries (shoulder)
• Epicondylitis (elbow)
• Trigger finger
• Muscle strains and low back injuries

CCOHS adds thoracic outlet syndrome, tension neck syndrome and De Quervain's disease, and links each one to typical occupational causes:

Disorder	Typical occupational risk factors (CCOHS)
Epicondylitis (elbow tendinitis)	Repeated or forceful rotation of the forearm combined with bending of the wrist
De Quervain's disease	Repetitive hand twisting and forceful gripping
Tension neck syndrome	Prolonged restricted posture
Thoracic outlet syndrome	Prolonged shoulder flexion, extending the arms above shoulder height, carrying loads on the shoulder

Most WMSDs affect the hands, wrists, elbows, neck and shoulders, because almost all work uses the arms and hands. Work that loads the legs can cause disorders of the hips, knees, ankles and feet, and the back is affected when the risk factors are present.

What causes work-related musculoskeletal disorders?

OSHA's risk factor list is a practical starting point:

• Excessive force. Lifting heavy objects or people, pushing or pulling heavy loads, or controlling tools.
• Repetition. The same motion or series of motions done frequently for long periods.
• Awkward or sustained postures. Reaching above shoulder height, kneeling, squatting, leaning over a counter, cutting with bent wrists, twisting the torso while lifting.
• Localized pressure. Pressing a body part against hard or sharp edges, or using the hand as a hammer.
• Cold. Cold temperatures combined with any of the above.
• Vibration. Whole-body or hand-arm.
• Combined exposure. Several risk factors together raise risk more than any one alone.

Our guide to the main types of ergonomic hazards gives office and industrial examples of each factor and shows how to control them.

OSHA notes that risk depends on posture, how often the task is done, how much effort it takes and how long it lasts.

Do psychosocial factors matter?

Yes. NIOSH lists psychosocial stressors among the work conditions that can cause or worsen WMSDs. CCOHS explains one mechanism: a stressed worker may have more muscle tension and use more force than needed. HSE's statistics report notes that organizational culture, health and safety climate and human factors can create the conditions for WMSDs, and that these factors rarely act alone.

How strong is the evidence?

NIOSH's major review, Musculoskeletal Disorders and Workplace Factors, concluded that a large body of epidemiologic research shows a consistent relationship between MSDs and certain physical factors, especially at higher exposure levels.

How common are WMSDs?

The numbers are large wherever they're measured.

Region	Figure	Source
United States	502,380 MSD cases with at least one day away from work over 2021-2022 (25.3 per 10,000 FTE workers, annualized)	BLS
United States	In 2018, MSDs were 30% of all private-sector cases with days away from work, with a median of 12 days away	BLS fact sheet
Great Britain	511,000 workers with a work-related MSD in 2024/25, 173,000 of them new cases, and 7.1 million working days lost	HSE
Great Britain	MSDs were 27% of all work-related ill health and 20% of working days lost to it in 2024/25	HSE
European Union	WMSDs remain the most common work-related health problem	EU-OSHA

HSE's breakdown shows where in the body the problems sit: 43% of British cases mainly affected the back, 41% the upper limbs or neck, and 15% the lower limbs. Lower-limb cases accounted for the most days lost per case, at an average of 23 days.

Which jobs have the highest risk of work-related musculoskeletal disorders?

OSHA's list of high-risk occupations, drawn from BLS data, includes:

• Registered nurses, nursing assistants and psychiatric aides
• Laborers and freight, stock and material movers
• Stock clerks and order fillers
• Heavy and tractor-trailer truck drivers
• Janitors and cleaners
• Production workers
• Maintenance and repair workers

In Great Britain, HSE found the highest MSD rates over 2022/23 to 2024/25 in construction, transportation and storage, and administrative and support services. By occupation, rates were above average for skilled trades, caring and service work, process, plant and machine operatives, and elementary occupations.

For sector-specific guidance, see our posts on warehouse ergonomics and ergonomics in manufacturing.

What are the early warning signs?

Pain is the most common symptom. CCOHS also lists joint stiffness, muscle tightness, redness, swelling, pins and needles, numbness, skin color changes and reduced sweating of the hands.

CCOHS describes three typical stages:

Stage	What it looks like
Early	Aching and tiredness during the shift that disappear overnight and on days off. No drop in performance.
Intermediate	Aching and tiredness start early in the shift and persist at night. Reduced capacity for repetitive work.
Late	Aching, fatigue and weakness persist at rest. Trouble sleeping and doing light duties.

Not everyone follows these stages neatly. The message from CCOHS is that the first pain, numbness or tingling are signals to rest and recover. Ignored, an injury can become longstanding and sometimes irreversible.

On the floor, OSHA suggests watching for workers shaking their hands, rolling their shoulders, modifying their tools, or bringing in their own wrist braces or back belts.

How do you prevent work-related musculoskeletal disorders?

Prevention works best as a process, not a one-off fix. NIOSH's primer Elements of Ergonomics Programs sets out seven steps:

1. Look for signs of a potential MSD problem.
2. Show management commitment and involve workers.
3. Train people to recognize and address problems.
4. Gather data to identify problem jobs.
5. Develop and evaluate controls.
6. Establish health care management.
7. Make the program proactive, so new jobs are designed right.

Which controls work best?

OSHA's guidance puts engineering controls first: lift-assist devices, lighter loads, repositioned work tables, conveyor diverters and redesigned tools. Administrative controls come next: two-person lifts, job rotation between tasks that use different muscle groups, and extra breaks. Personal protective equipment has only limited effectiveness for ergonomic hazards.

CCOHS adds a caution on job rotation: it only helps if the tasks are genuinely different and the workstations are well designed. It won't work while a very high pace persists.

Why does early reporting matter?

OSHA says early reporting, diagnosis and intervention can limit injury severity, improve treatment, reduce the chance of permanent damage and reduce workers' compensation claims. Our breakdown of what MSD claims really cost employers shows how to put a number on that. It also shows you which jobs need attention first. Make it easy and safe for people to report symptoms.

How do you find which jobs to fix first?

Start with injury logs and complaints, then screen jobs with a checklist and score the flagged tasks with a method such as REBA, RULA or the NIOSH lifting equation. Our guide to what an ergonomic assessment involves walks through that process.

ViveLab's AI posture analysis can speed up the posture scoring step by estimating REBA or RULA scores from phone video, processed on the device. It's an estimate, so a trained assessor should review it before it drives decisions.

Next steps

Screen your highest-complaint job with the ergonomic assessment checklist and note which risk factors it flags. The tool page also explains how to turn checklist flags into a prioritized fix list.