Recently I provided an education session on injury reduction in Diagnostic Medical Sonography. The following is an excerpt from the document I produced for the course. The image above was created by Ivan Shidlovski and is being used under a non-commercial license.
Causes of Workplace Musculoskeletal Disorders (WMSDs)
It has been stated that the “physiological cause of a repetitive strain injury (RSI) is the accumulation of small repetitive stresses that accumulate over time (Muir et al., 2004). When sonographers are conducting scans, if there is not enough rest to recover, there could be loss of the muscle’s ability to recover (Muir et al., 2004). This can lead to a WMSD. It was noted that medical sonographers are at risk if they are conducting more than 100 scans per month and an average duration of 25 minutes (Muir et al., 2004).
Other factors to consider are:
- One-sided static working position (Monnington et al., 2012).
- Prolonged pinch gripping of the ultrasound transducer (Monnington et al., 2012).
- Abducting shoulder greater than 20 degrees (Muir et al., 2004).
- Twisting and bending wrists while applying pressure (Muir et al., 2004).
- Awkward postures (Muir et al., 2004).
- Poor equipment design for workplaces (Muir et al., 2004).
- Reaching too much (Muir et al., 2004; Habes & Baron, 1999).
- Reaching too far (Muir et al., 2004; Habes & Baron, 1999).
- Taking too few rest breaks between exams (Monnington et al., 2012; Habes & Baron, 1999).
One interesting fact that was pointed out by NIOSH was the need for mini breaks during the examination (Habes & Baron, 1999). They noted that “if a sonographer pushes down on the abdomen for a period of 15 seconds to obtain a necessary fetal view, he/she should release the scan head and recover for 15 seconds before proceeding with the examination” (Habes & Baron, 1999, p. 5). If the exertion time lasts one minute, then 100 seconds of recovery is required.
It was also noted that “work organization (psychosocial) factors (such as demand, control, support and role)” can be associated with musculoskeletal problems in sonographers (Monnington et al., 2012, p. 1).
Strategies to Reduce Risk
As per safety systems literature, there is a hierarchy of controls that are used to address physical hazards/ergonomic concerns. This ranges from engineering controls to administrative controls to personal protective equipment (WCB NS, 2015; WorkSafeBC, 2017). The most effective control is engineering and PPE is the least effective because if the PPE does not fit well and/or it fails, the employee will still be exposed to the risk (Government of Alberta, 2011).
Engineering controls are the “physical arrangement, design or alteration of workstations, equipment, materials, production facilities or other aspects of the physical work environment, for the purpose of controlling risk” (WorkSafeBC, 2017). Some of the examples of engineering controls identified by the Government of Alberta (2003) are:
- Substitution of a hazardous process with a less hazardous process.
- Process modification.
- Use of material handling equipment (to replace manual handling).
- Automated processes.
- Ergonomically designed equipment and facilities.
Please note that material handling equipment is synonymous with patient handling equipment (i.e. mechanical lift, air-assisted lateral transfer devices, etc.).
Administrative controls refers to the “provision, use and scheduling of work activities and resources in the workplace, including planning, organizing, staffing and coordinating, for the purpose of controlling risk” (WorkSafeBC, 2017). The Government of Alberta (2003) identified some administrative examples:
- Policies and procedures.
- Orientation and training.
- Purchasing standards and procedures.
- Work scheduling.
- Job rotation.
- Warning signs.
- Maintenance and cleaning programs.
- Separate lunchroom and break facilities.
These controls can also include conducting a risk assessment of the treatment areas and ensuring an appropriate work-to-rest ratio to ensure decreased chance of injury to muscles.
PPE refers to items such as gloves, footwear, lead aprons and devices to protect against contact stress (WorkSafeBC, 2017; Government of Alberta, 2011).
Specific to Medical Sonography
The following are some strategies that are specific to medical sonography:
- Work organization:
- Increased control of work (Monnington et al., 2012).
- Engineering controls identified by Baker (2003):
- Fully adjustable equipment.
- Easily accessible controls for braking. Central locking is preferable.
- Automated systems (i.e. voice activated).
- Height-adjustable handles suitable for transporting the equipment.
- Monitor and control panel have independent height adjustability.
- Height-adjustable table that goes low enough to allow patients to get on and off independently and high enough for the sonographer to scan in a seated or standing position while maintaining shoulder abduction of less than 30 degrees.
- Open access from all sides to allow the user to put their knees and feet underneath, if required.
- Height-adjustable chair with sufficient range to suit most users. Ensure shoulder abduction of less than 30 degrees when scanning in seated position.
- Administrative controls:
- Balance workload to enable rest breaks (Monnington et al., 2012).
- Take at least three rest breaks of 10 minutes to optimize muscle recovery (Muir et al., 2004).
- Take short breaks during the examination to relieve muscle fatigue (Habes & Baron, 1999).
- Switch scanning hands for task variation (i.e. if right-handed, scan with left hand) (Monnington et al., 2012).
- Decrease duration of static posture (Murphy & Russo, 2000).
- Decrease hand-grip pressure (Murphy & Russo, 2000).
- Minimize awkward postures (Murphy & Russo, 2000).
- Increase tissue tolerances through exercise and adequate rest (Murphy & Russo, 2000).
- Provide continuing education on ergonomic risk factors and enable sonographers to come up with appropriate solutions as a team (Pike et al., 1997).
- Provide education on properly setting up the chairs that have been purchased (Pike et al., 1997).
For an expanded list of strategies, please see the references listed above in each control.
When to Seek Treatment
Early diagnosis and intervention is required to address a WMSD (Burnage et al., 2007; Murphy & Russo, 2000; Muir et al., 2004; Igbal & Alghadir, 2017). The difficulty in the literature is determining what is “early”? Anecdotally, the following guideline should be used:
- Pain, numbness, tingling lasting more than 2 hours that does not decrease with rest.
From the clinical orthopaedic knowledge of the current IPC, let us discuss a scenario for further clarification. If you are working four shifts in a row (e.g. Monday, Tuesday, Wednesday, Thursday) and you notice tingling in your arm/hand that is increasing in intensity and frequency over the four shifts, but then goes away over the next three days off, you need to address the ergonomics in your area and seek medical treatment from a physiotherapist, chiropractor or massage therapist. They should provide you with posture and work-rest ratio education and exercises to try and decrease the symptoms. They may also provide you with an assistive device such as a splint.
Baker, J. (2003, May). Industry Standards for the Prevention of Work-Related Musculoskeletal Disorders in Sonography. Consensus Conference hosted by Society of Diagnostic Medical Sonography. Retrieved from https://www.soundergonomics.com/pdf/WRMSDweb.pdf
Burnage, J., Cattell, G., Dixon, A., Kilbourn, P., Oates, C., & Palmer, D. (2007). Prevention of Work-Related Musculoskeletal Disorders in Sonography. The Society of Radiographers.
Canadian Centre for Occupational Health and Safety (CCOHS). (2017a). OSH Answers Fact Sheets. Work-related Musculoskeletal Disorders (WMSDs). Retrieved from https://www.ccohs.ca/oshanswers/diseases/rmirsi.html
Canadian Centre for Occupational Health and Safety (CCOHS). (2017b). OSH Answers Fact Sheets. Work-related Musculoskeletal Disorders (WMSDs) – Risk Factors. Retrieved from https://www.ccohs.ca/oshanswers/ergonomics/risk.html
Government of Alberta. (2011). Best Practices and Guidelines for Occupational Health and Safety in the Healthcare Industry, Vol 4: Best Practices for the Assessment and Control of Physical Hazards. Retrieved from https://work.alberta.ca/documents/WHS-PUB-bp012.pdf
Habes, D.J., & Baron, S. (1999). NIOSH Ergonomics Evaluation of Sonographers at St. Peter’s University Hospital: NIOSH health hazard evaluation, (HETA 99-0093-2749). Retrieved from https://www.cdc.gov/niosh/hhe/reports/pdfs/1999-0093-2749.pdf
Igbal, Z.A., & Alghadir A.H. (2017). Cumulative trauma disorders: A review. Journal of Back and Musculoskeletal Rehabilitation. Advance online publication. doi: 10.3233/BMR-150266 (Epub ahead of print).
Monnington, S.C., Dodd-Hughes, K., Milnes, E., & Ahmad, Y. (2012). Risk Management of Musculoskeletal Disorders in Sonography Work. Project Report from Health and Safety Executive. (2012). Retrieved from http://www.hse.gov.uk/healthservices/management-of-musculoskeletal-disorders-in-sonography-work.pdf
Muir, M., Hrynkow, P., Chase, R., Boyce, D., McLean, D. (2004). The Nature, Cause, and Extent of Occupational Musculoskeletal Injuries Among Sonographers. Recommendations for Treatment and Prevention. Journal of Diagnostic Medical Sonography, 20(5), 317-325. doi: 10.1177/8756479304266737
Murphy, C., & Russo, A. (2000, July). An Update on Ergonomic Issues in Sonography Report. Healthcare Benefit Trust. Retrieved from https://www.soundergonomics.com/pdf/Update_on_Ergo_Issues.pdf
Pike, I., Russo, A., Berkowitz, J., Baker, J.P., Lessoway, V.A. (1997). The Prevalence of Musculoskeletal Disorders and Related Work and Personal Factors Among Diagnostic Medical Sonographers. J Diagnostic Med Ultrasound, 13, 219-227.
Workers’ Compensation Board of Nova Scotia (WCB NS). (2015). Small Business Safety Toolkit. Retrieved from http://wcb.ns.ca/toolkit.aspx
WorkSafeBC. (2017). Occupational Health and Safety Regulation, Part 01 – Definitions. Retrieved from https://www.worksafebc.com/en/law-policy/occupational-health-safety/searchable-ohs-regulation/ohs-regulation/part-01-definitions