Falls on the Same Level, Trips, and Slips: Can They Be Prevented?

Slips, trips, and falls on the same level have consistently appeared among the top causes of workplace injuries in the U.S.^1,2 In 2020, there were nearly 128,000 nonfatal, same-level falls that resulted in days away from work.³ That means an average of just over 500 same-level falls each day, based on about 250 workdays (without weekends and holidays).⁴

A troubling rate of same-level falls, trips, and slips may persist even after employers have followed the well-established recommendations: repair holes and uneven walking surfaces, remove obstacles, practice good housekeeping, clean up spills, cover cables, secure mats/rugs, ensure areas are well-lit, post signage, and quickly deal with mud and water tracked in from outside in adverse weather.⁵

It may be time to consider factors more directly related to employees – factors to which occupational health professionals bring undeniable and unparalleled expertise and experience. These include:

1. Poor balance and the science of postural control
2. Factors in relationship to the work environment
   • Hazardous exposures: chemicals and heat
   • The nature of work: postures, strength, and too much sitting
   • Occupational footwear design
3. Medical conditions
   • Sleep deprivation
   • Ototoxic medications

Poor balance and the science of postural control

Most people are familiar with balance problems as a potential aspect of more advanced age. However, research has shown that falls due to gait and balance problems occur across all age groups (young adults, middle-aged adults, and older adults) with age-related increases in incidence.⁶

In the dynamics of human movement, postural instability/poor balance may increase one’s risk of falling. Good postural control is seen when an individual is able to maintain body stability (not swaying or falling) in a variety of static postures or activities/actions; the body is able to smoothly respond to sensory stimuli about hazards in the environment by making minuscule adjustments.

Postural control has two components: postural orientation and postural equilibrium. Postural orientation refers to an alignment of the parts of the body with the environment when performing a task. Postural equilibrium is the ability to stabilize the body’s center of mass through sensorimotor coordination. These aspects are interdependent and together support good balance.⁷

Three important sensory systems and two parts of the body contribute to establishing and regulating postural control. The three sensory systems are:

• Proprioception (the sense of movement, force, and body position)
• Vision (interpretation of the surrounding environment)
• Vestibule/vestibular or the central part and related parts of the bony labyrinth structures in the inner ear (balance and spatial orientation)

The two parts of the body are, first, the spine, which provides postural stability, and it does this in conjunction with, second, the cerebellum in the hind-brain or the lower part of the brainstem. The cerebellum provides coordination.

Specially trained physical therapists in occupational health care can assess the function of sensory systems through various tests and maneuvering/manipulation of parts of the body. Michael Morgan of Concentra® has addressed the use of vestibular therapy in restoring an employee’s balance. Morgan is associate director of therapy operations/physical therapy director for Concentra in Arizona.⁸

The three sensory systems involved in postural control are both innate (what we are born with) and adaptive (change over time/respond to stimuli). What this means in the workplace is that an employee with innate postural instability may present a higher safety risk in a job that requires good balance. The inverse is also true: If a job requires awkward postures and intense physical demands for extended periods of time, this may worsen an employee’s postural control now and in the future.

Relationship to the work environment

Hazardous exposures: chemicals and heat

Pesticides, heavy metals, and solvents affect the central nervous system and the musculoskeletal system. This can impact functional abilities, such as balance and gait when carrying out tasks. These functional outcomes may result in injuries and a risk of developing chronic neurodegenerative and degenerative musculoskeletal disorders later in life.⁹

Heat stress and high physical exertion also have been shown to adversely affect balance. Texas A&M researchers studied the effects of heat stress and also physical exertion in normal temperatures when repeated muscle contractions increase metabolic temperature. In both cases, they concluded that proprioceptors (sense of movement, force, and body position) and the vestibular system (balance) were compromised.¹⁰

Nature of work: awkward postures, repetitive lifting, and too much sitting

Awkward postures are any body position that places stress on the body and may require increasing exertion. Some examples are twisting the body, squatting or kneeling, bent neck, back, or wrist, and arms raised or extended outward.¹¹ Awkward postures are the antithesis of a neutral body position, where the body is aligned and balanced. There is minimal stress on the body and the joints are kept aligned easily while sitting or standing.¹²

Research published in 2020 demonstrated the effect of awkward postures on postural stability and balance (or body weight distribution) by comparing instrumental musicians with non-musicians. Instrumental musicians must maintain certain awkward postures for extended times during practice time and performances.

The results showed that the postures of the pianists, violinists/violists, and guitarists caused their weight distribution to shift significantly to the left compared to controls (non-musicians); meanwhile, drummers and cello and bass players had significant weight distribution shifts to the right compared to controls. These postural imbalances persisted outside of performance/practice time, leading to balance disorders that would likely require health interventions to offset adverse effects.¹³

Repetitive lifting of heavy weight is an awkward posture that has been quantified to show that construction laborers must use far more strength in lifting on a regular basis than workers in all other occupations, according to the U.S. Bureau of Labor Statistics.¹⁴

The comparison between construction laborers and the average for all other occupations is striking.*

Heavy strength required

39% of construction laborers

9% of all other occupations

Medium strength required

54% of construction laborers

28% of all other occupations

Heavy + medium strength total requirement

93% of construction laborers

37% of all other occupations

Lift and/or carry requirements

59 pounds for construction laborers

26 pounds for all other occupations

*Values have been rounded.

These unrelenting, high strength requirements take on additional importance when considering postural control and balance. A research study evaluated the effects of different weights and awkward lifting postures on balance control through a simulation of repetitive lifting tasks.

The researchers evaluated increased center of pressure (CoP) parameters, which have been associated with greater postural instability and/or a need for the body to make frequent postural corrections to maintain balance.

They found that CoP parameters were increased significantly when lifting heavier weight and when fatigue was induced by use of stoop and squat lifting postures. Fatigue was also shown to adversely affect balance on unstable surfaces. They concluded: “Repetitive lifting of heavier weights would significantly jeopardize individuals’ balance control on unstable supporting surfaces, which may heighten the risk of falls.”^15A,15B

Because repetitive lifting involving different weights and awkward postures is a significant activity for construction workers, they may benefit from training to recognize the role of the weight they lift and the fatigue they experience during repetitive lifting tasks. Such training “would result in enhanced balance control through redesign of work and improved workers’ behavior,” the researchers said.

Balance is not just affected by intense physical requirements like those placed on construction laborers. At the other end of the spectrum, sedentary office workers face challenges due to too much sitting. A research study enrolled participants with pressure sensitivity in the C4-C5 vertebrae in the midsection of the cervical spine and L3-L4 vertebrae in the middle of the lumbar spine.

“Working while sitting for hours limits one’s ability to control body movement and induces many postural and functional dysfunctions,” said researchers. “Such changes may become fixed, causing the locomotor system’s temporary inability to maintain an upright position and a stable body posture.”¹⁶

Participants were provided a five-month health training program to improve postural balance, and researchers waited to see what impact, if any, the balance exercises would have on spinal pain and balance performance.

At the conclusion of the training program, researchers observed an improvement in postural stability and balance, which they said correlated with reduced pain intensity in the spinal tissues. Office workers with lumbar dysfunction had improved proprioception (the sense of movement, force, and body position), which correlated with reduced pain in the L3-L4 vertebrae.

Occupational footwear design

Aspects of occupational footwear design – elevation of the shaft, toe protection, heel height, and the hardness of midsoles – can have an impact on postural stability. In an evaluation to compare low-top shoes, tactical work boots, and steel-toed work boots, researchers simulated a four-hour occupational workload and measured participants’ postural sway and postural equilibrium at 30-minute intervals.

They found that the higher boot shaft of the tactical work boot and the steel-toed work boot provided better ankle joint support and stability to minimize postural sway. Meanwhile, the low-top shoe resulted in increased postural sway and lower postural stability, hence, a greater potential for falls and fall-related injuries.¹⁷

Medical conditions

Sleep deprivation

Postural balance can be disturbed by sleep deprivation – either chronic or just for one night – regardless of an employee’s age or activity level. Sleep that is inadequate in duration or quality disrupts the regulatory mechanisms of postural balance, although the different disruptive effects induced for each system – proprioception, vision, or vestibule/vestibular – “are not fully known,” researchers said.¹⁸

One well-known reason for chronic poor sleep quality is obstructive sleep apnea (OSA), a sleeping disorder in which breathing stops and restarts several times a night, interrupting sleep, due to periodic collapse of the upper airway. Both the severe or mild-to-moderate (non-severe) forms of OSA have been shown to be associated with impaired postural balance and the risk of falling.^{19, 20}

Men are two to three times more likely to have OSA than women, and sleep apnea is more common in older adults. Being over the recommended weight for good health increases the risk of OSA for both men and women.²¹

Ototoxic medications

Ototoxicity, or a link between certain medications and dysfunctions in hearing and balance, was first observed in 1944 when streptomycin was used in the successful treatment of tuberculosis. Today, “a great deal of clinical and basic scientific research into the etiology and mechanisms of ototoxicity” shows that “many well-known pharmacologic agents have toxic effects to the cochleovestibular system (hearing/balance),” says Pamela Mudd, MD.²² These include antibiotics called aminoglycosides, salicylates in some over-the-counter medications, and loop diuretics, used to treat fluid-overload conditions, like heart failure and edema.

Hearing loss may take weeks or months, or it may never occur. Severe toxicity in the vestibule can lead to dysequilibrium or dizziness. An occupational health provider can help advise on the use of these drugs, which must be weighed against the potential risks.^23,24

Contact Concentra for help

The causes of same-level falls, slips, and trips extend beyond flooring, lighting, and general housekeeping in the workplace. Employees may have compromised sensory systems and poor postural control and balance, which can be caused by health conditions, hazardous exposures, ototoxicity of certain medications, sleep deprivation, and more. Concentra’s occupational health medical professionals can provide insightful clinical guidance to prevent such work-related injuries and accidents, the cause of which otherwise may not be easily identified.

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NOTES

1. Preventing Slips, Trips, and Falls in the Workplace. Travelers. Accessed: October 11, 2023.
2. Falls – Same Level. National Safety Council. Accessed: October 11, 2023.
3. Falls – Same Level. National Safety Council. Accessed: October 11, 2023.
4. Working days in 2020. Accessed: October 11, 2023.
5. “Prevent same-level slips, trips, and falls.” Safety+Health. February 24, 2019.
6. Talbot LA, Musiol RJ, Witham EK, Metter EJ. Falls in young, middle-aged, and older community-dwelling adults: peceived cause, environmental factors, and injury. BMC Public Health. August 2005. https://doi.org/10.1186/1471-2458-5-86.
7. The Postural Control System. Physiopedia. Accessed: October 4, 2023.
8. “Vestibular Therapy: Restoring Balance in the Injured Employee,” by Michael Morgan, PT, DPT, OCS. Concentra.com. December 24, 2019.
9. Ross JA, Shipp EM, Trueblood AB. Ergonomics and Beyond: Understanding How Chemical and Heat Exposures and Physical Exertions at Work Affect Functional Ability, Injury, and Long-Term Health. Human Factors: The Journal of the Human Factors and Ergonomics Society. 2016;58(5):777-795.
10. Ross JA, Shipp EM, Trueblood AB. Ergonomics and Beyond: Understanding How Chemical and Heat Exposures and Physical Exertions at Work Affect Functional Ability, Injury, and Long-Term Health. Human Factors: The Journal of the Human Factors and Ergonomics Society. 2016;58(5):777-795.
11. Awkward Postures. Hazmat OSHA Safety Training Courses. November 7, 2016.
12. “The Most Important Benefit of Maintaining a Neutral Posture,” by Matt Middlesworth. ErgoPlus Blog. February 2, 2023.
13. Nusseck M, Spahn C. Comparison of Postural Stability and Balance Between Musicians and Non-Musicians. Frontiers in Psychology. June 2020;11:1253, doi:10.3389/fpsyg.2020.01253.
14. Spotlight on Statistics: Strength level required, percent of workers at each level by occupation, 2021. U.S. Bureau of Labor Statistics. Accessed: October 13, 2023.
15. A. Antwi-Afari MF, Li H, Edwards DJ, et al. Effects of different weights and lifting postures on balance control following repetitive lifting tasks in construction workers. Emerald Insight. International Journal of Building Pathology and Adaptation. 2017;35(3).15B. Open access text for Antwi-Afari MF, Li H, Edwards DJ, et al. Effects of different weights and lifting postures on balance control following repetitive lifting tasks in construction workers.
16. Kalwa M, Ostrowska B, Zywlen U, Stefaniak T. Workplace exercises. Improvement of postural stability of office workers with spine dysfunctions following a 21-week health training programme. Baltic Journal of Health and Physical Activity. 2018;10(4):119-130.
17. Chander H, Garner JC, Wade C, Knight AC. Postural Control in Workplace Safety: Role of Occupational Footwear and Workload. Safety. MDPI. 2017;3(3):18.
18. Paillard T. Detrimental effects of sleep deprivation on the regulatory mechanisms of postural balance: a comprehensive review. Frontiers in Human Neuroscience; April 13, 2023;17: 14:1146550. doi: 10.3389/fnhum.2023.1146550.
19. What is Sleep Apnea? National Heart, Lung, and Blood Institute. Updated: March 24, 2022.
20. Paillard T. Detrimental effects of sleep deprivation on the regulatory mechanisms of postural balance: a comprehensive review. Frontiers in Human Neuroscience; April 13, 2023;17: 14:1146550. doi: 10.3389/fnhum.2023.1146550.
21. Sleep apnea. Mayo Clinic. April 3, 2023.
22. “Ototoxicity,” by Pamela A. Mudd, MD. Medscape. December 29, 2021.
23. "Ototoxicity. Cleveland Clinic. Accessed: October 13, 2023.
24. “Ototoxicity,” by Pamela A. Mudd, MD. Medscape. December 29, 2021.