Key points
- Collect medical evidence of work-related musculoskeletal disorders (WMSDs) from OSHA logs, medical records, claims, absentee records, and job transfer applications.
- Conduct interviews and symptom surveys to identify the onset and nature of possible WMSDs.
- Provide periodic medical exams designed and administered by a health care provider.
Overview
After identifying the signs of potential WMSDs and providing training, next you can determine the scope and characteristics of potential risks. Complete the next step by collecting health and medical evidence of WMSDs.
It is essential to follow up on workers whose jobs cause undue physical fatigue, stress, or discomfort. If employees report their symptoms early, you can take corrective measures to delay the development of WMSDs.
If workers in one department report more WMSD problems than other departments, it is best to immediately study possible risk factors.
Compute the incidence rate and prevalence rate of WMSDs
Begin your review from the date of your last equipment or process change.
Gather information on the extent of WMSDs from:
- OSHA logs of work-related injuries and illnesses
- Company medical records
- Workers' compensation claims
- Insurance claims
- Absentee records
- Job transfer applications
Employers can calculate incidence rates based on the number of new cases reported and total hours worked in a calendar year. Incidence rates for partial years can be calculated using hours worked through the time period in question.
Incident rates are typically computed for the Total Recordable Cases (TRC) incidents. The TRC rate includes both cases with and without lost workdays. The incidence rate also includes cases with only Days Away, Restricted days or Transferred to another job (DART).
When the total hours worked by all workers is not available, use an estimate of 2,000 hours/year per each full-time worker.
Compare incidence rates to those of other departments, other industries, occupations, or the nation using The U.S. Bureau of Labor Statistics.
Incidence rate (IR)
An equation where the number of new cases is calculated per 100 workers, which is equivalent to 200,000 work hours.
Prevalence rate (PR)
PR is a calculation that considers all active cases in a given time period regardless of when the case originated.
Conduct interviews and symptom surveys
Use interviews and symptom surveys to identify the onset and nature of possible WMSDs that might otherwise go unnoticed.
Surveys ask for information that can help point to the cause of WMSDs including:
- Personal information (age, sex, occupational history, present job).
- Location, timing, duration, and severity of MSD symptoms.
- Difficulty of job task.
- Symptoms at previous jobs.
- Medical history.
Employers can also include a body map so that workers can illustrate their discomfort.
A body map rank-orders the frequency and severity of complaints for each body part. You can then average this data for each department and/or job. Administer surveys that are anonymous, voluntary, and to be completed on work time only.
Out of respect for workers’ personal information, use surveys only if the company is prepared to act on the results.
Provide periodic medical exams
Gather evidence of WMSDs from periodic medical exams designed and administered by a health care provider.
Medical exams happen when workers give their medical history and complete a physical exam. Health care providers will ask workers to complete tests and report if they feel any pain. These tests can include range of motion tests, tenderness tests.
Physicians conducting medical exams should have prior knowledge of workers’ existing diseases and job titles. WMSDs are present when MSDs in a certain part of the body are associated with a particular job function. Incidence rates and prevalence rates of MSDs are confirmed and specified by interviews, symptom surveys, and medical exams.
Example
Cashiers have more WMSDs in their hands and wrists than other supermarket workers. Workers who perform the most checkout tasks or work longer shifts have the most WMSD problems.
Conduct job analyses
Brannick, Levine, & Morgeson (2007)1 define job analysis as the study of a job and all of its components. Any job can be described in terms of tools, equipment, materials, workstation layout, physical environment, job demands, or organizational climate. A human resources professional or other experienced personnel conducts a job analysis to describe everything that happens on the job. Conducting a job analysis is important to assess potential WMSD hazards.
There is no standard protocol for conducting a job analysis, so you may want to follow suggested best practices:
- Record each job summary, including the total time for each task.
- Ask employees if the way their job is done has changed over time.
- Divide the job into separate tasks and actions.
- Count and categorize the risk factors in each task and action.
- Determine the underlying cause for risk factors for task and action.
- Record the severity, frequency, and duration of each risk factor.
When completing the job analysis make sure to consider:
- Work postures.
- Measure muscle force and spinal disc pressure.
- Phsyical demands
- Consider whole body vibrations, oxygen consumption, and heart rate.
- Workstation heights and reach distances.
- Workstation layouts.
- Work surfaces.
- Consider slip resistance, hardness, and surface edges.
- Psychological tests.
- Consider perceived exertion.
Use current assessment tools
It may be difficult to determine what level or amount of exposure is harmful to your workers. Use available resources to help.
NIOSH uses a variety of approaches to determine the appropriate job analysis for each workplace situation. You can use the NIOSH Revised Lifting Equation to assess the risks associated with lifting and lowering tasks. You can compare the muscle strength required to perform a task to the strength of the individual workers performing this task. You can ask your workers to determine what they consider acceptable working conditions.
External assessment tools
Whole body and screening
- What it is: A checklist that focuses on the upper extremity, back & legs, and environmental job settings (e.g., lighting).
- Why we use it: To determine concerning elements in a job task.
- What it is: A table that focuses on the upper extremity, back and legs, and environmental job settings.
- Why we use it: To determine task areas with high risk levels.
- What it is: Tables and multiple steps that focus on back, shoulder/arm, wrist/hand, and neck.
- Why we use it: To determine low, moderate, high, or very high exposure levels.
- What it is: Tables and multiple steps that focus on the neck, trunk, legs, and arm & wrist positions.
- Why we use it: To determine negligible, low, medium, high or very high risk levels.
- What it is: A table that focuses on neck, shoulders, back, arms/elbows, wrists/hands/fingers, legs/knees, & ankles/feet/toes by task effort, duration, and frequency.
- Why we use it: To determine if your range of muscle fatigue puts you at risk for WMSDs. If you meet a light, moderate, heavy, or very heavy risk level, you should modify the task accordingly.
- What it is: A table based on the ISO 2631 standard that focuses on the upper and lower extremities.
- Why we use it: To determine the level and risk created by your task.
- What it is: A checklist that focuses on low back, hand & wrist, neck & shoulder, and knee.
- Why we use it: To determine the range of risk created by your task (i.e., none, caution, or hazard)..
Back
- What it is: A checklist that focuses on the concern and risk for the back. It looks at the position of the object, and frequency and duration of the lift.
- Why we use it: The results are compared to a given standard to determine the action level.
- What it is: Tables that focus on push/pull, carrying, and lift/lowering.
- Why we use it: To determine the percentile of men and women that this task would be acceptable to.
- What it is: An equation designed to assess manual lifting that focuses on the back. It looks at the object’s weight, horizontal and vertical position, twisting angle, duration, frequency and coupling.
- Why we use it: to determine an acceptable weight for that task.
- What it is: a table and equations that focus on back posture, load moment and direct compression.
- Why we use it: the results are compared to a given standard to determine if more detailed analysis or changes are needed to the task.
- What it is: a combined checklist and multiple steps for manual lifting that focus on the back. It factors in an object’s weight, and the frequency and posture of the task.
- Why we use it: the results are compared to a given standard to determine if the task is a WMSD hazard.
Upper body
- What it is: a table that focuses on each hand’s activity level and estimated normalized peak force.
- Why we use it: the results are compared to an action limit and threshold limit value to evaluate the risk level.
- What it is: a table based on the ANSI/ASA S2.70-2006 standard that focuses on hand arm vibration.
- Why we use it: to determine the level and risk of exposure to vibration.
- What it is: a table that focuses on each hand. It looks at 6 different risk factors.
- Why we use it: to determine the range of risk created by your task (i.e., safe, uncertain, some risk, or hazardous risk).
- What it is: tables and multiple steps that focus on the neck, arm and wrist positions.
- Why we use it: to determine the range of risk created by your task (i.e., an acceptable task, further investigation, or implement changes).
- What it is: a combined checklist and graph that focus on hand-arm vibration hazards.
- Why we use it: to determine the range of risk created by your task (i.e., okay, caution, or hazard).
- Brannick, M. T., Levine, E. L., & Morgeson, F. P. (2007). Job and work analysis: Methods, research, and applications for human resource management (2nd ed.). Sage Publications, Inc.