Back pain affects 60 – 80% of the population, which means it affects personal trainers as well as their clients. There are 61.7 million back pain patient visits to doctors each year (Licciardone, 2008). Strains to the muscles and tendons are the most common causes of low back pain (McGill, 1997). Back pain or injury does not just occur, they are a result of repeated micro-traumas leading up to a major failure of tissue (McGill, 1997). There are physical and psychological risk factors as well at individual and occupational risk factors (Bigos, et al., 1992). Prevention of back injury needs to focus on exercise both in and out of the work-place.
- Review the research on back injuries as it relates to risk factors.
- Discuss the mechanisms of injury.
- Provide an objective interpretation of back injury prevention.
- Incorporate exercises that can be used to prevent back pain.
Stuart McGill, Ph.D., a spinal biomechanist at the University of Waterloo, Canada, states, " … low back injury is a complex issue and will only be successfully addressed by those willing to combine the wisdom of different approaches and to form an integrative approach that is scientifically justifiable." There are 61.7 million low back pain (LBP) patient visits to doctors each year (Licciardone, 2008). 60 - 80% of the population will have some kind of back pain or injury. Back pain is the most frequent cause of activity limitation among those under 45 years (Andersson, Fine, and Silverstein, 1995). 80 to 90% of those with back pain will recover within three to six days, regardless of treatment (Andersson, Fine, and Silverstein, 1995).
Intervertebral Discs and Back Pain
Andersson, Fine, & Silverstein (1995) indicate 1 – 5% of back pain is related to an injury to the intervertebral disc. Andersson, Fine, & Silverstein (1995) state: "It is important to recognize that the presence of a narrowed intervertebral disc (on x-ray) is not correlated with the risk for, or the presence of, a disc herniation, and it does not provide an explanation of the patient's pain in most cases.” The best diagnostic tool for a herniated disc is the straight leg-raising test, which will elicit pain when the nerve root has pressure from a herniated disc.
Videman, Nurminen, and Troup (1990) documented the increased risk of disc herniation for those who sit a lot. The mechanical changes of the disc caused by sitting are increased intra-disc pressure and increases in posterior disc strain. McGill (2001) suggests the workers have a 50-minute sitting limit, after which they stand up, move, and/or stretch. In physically demanding jobs, repetitive movements (most commonly trunk flexion followed by extension to a neutral spine) of the spine can cause micro-traumas to the disc(s), which can lead to a herniated disc (McGill, 1997).
Most Common Cause of Back Injury
As mentioned earlier, strains to the muscles and tendons are the most common cause of low back pain (McGill, 1997). Most back injuries are caused by micro-traumas from repeated movements, eventually leading to a severe strain (McGill, 1997).
In an occupational, exercise, recreational, household, or gardening setting, a person can perform movements causing the micro-trauma(s) for weeks, months, or years until a movement causes failure of the tissue, resulting in severe trauma. As such, most back injuries do not just happen. Common movements, or postures, that can cause micro-traumas include: repeated unbalance or incorrect lifting, prolonged static postures of the spine such as trunk flexion without reversal of the posture, chronic physical stress on spine and muscles, and/or chronic sitting with little movement.
Psychological and Individual Risk Factors
Risk factors include older age, poor general health (smoking), physical stress on spine (vibration), and psychological stress (depression) (Parreira, et al., 2018). Other psychological risk factors for back pain include: a job with chronic stress (chronic stress releases cortisol that has been implicated in muscle and tendon injury), low work satisfaction, low motivation or boredom, and mental fatigue, which may cause a worker to “forget” to lift properly (Bigos, et al., 1992). Other risks for injury or pain include: lack of sleep, emotional instability, alcohol and/or drug abuse, smoking, family problems, excessive body weight, physical inactivity, physical activity (too much exercise or incorrect movement), poor muscle endurance, and previous back injury. Al-Salameen, Abugad, and Al-Otaibi (2019) found that workers who did not exercise and those who smoked had an increased risk of low back pain.
Occupational Risk Factors
Al-Salameen, Abugad, and Al-Otaibi (2019) suggest that workplace ergonomic interventions may reduce the risk of low back pain. Physical risk factors at work include: continuous heavy physical work, prolonged sitting, chronic “high risk” postures when standing (workers can be forced into chronic trunk flexion because their workstation is too low), repetitive bending, twisting, pushing, pulling and lifting, slipping, tripping or falling, vibration during continuous driving, poor muscle endurance (this is especially true for people who’s job requires lifting and carrying), twisting a “loaded” spine (a spine is “loaded” when a worker picks up, carries, or puts down a load), and not using mechanical lifting devices.
Can Back Injuries Be Prevented?
Prevention of back injury needs to focus on exercise in and out of the workplace . Exercise out of the workplace includes working out to reduce the adverse effects of stress. Exercise to improve muscle endurance of the muscles supporting the spine is important (McGill, 2001). Muscle endurance is the key component of fitness for industrial workers because they perform their work over long periods of time each day. As McGill (2001) suggests performing core strengthening exercises in a neutral spine position and avoiding end range of motion in flexion and extension. McGill (2001) further indicates that the spine is like a tent pole; the tighter the guide wires, the more stable the pole will be. The stronger the muscles supporting the spine (rectus abdominus, internal and external obliques, transverse abdominus, and erector spinea group), the more stable the spine will be and theoretically, less susceptible to injury.
Workplace Exercises for Back Injury Prevention
Exercises in the work-place can include pre-work warm-up routines (PWWP) and workstation stretching/range or motion exercises (WSS). Hilyer, et al., (1990) used 469 municipal firefighters to examine the effect of work-place stretching on incidence and severity of joint injuries. The authors state, “Although incidence of injury was not significantly different from the experimental and control groups, injuries sustained by the experimental group resulted in less lost time costs. Findings indicate that the flexibility training group program had a beneficial effect on reducing the severity and costs of joint injuries in the firefighting population.”
Many companies give anecdotal evidence of the benefits of PWWP routines for their employees. Some benefits include: Worker’s Compensation insurance claims costs were 83% lower one year after the implementation of a PWWP, healthier and more versatile workforce, and PWWP caused several people to schedule fitness assessments to join the on-site fitness center. Bracko (1998) reports the following benefits from an eight year voluntary PWWP program at a manufacturing plant: only 14% of injuries occurred to participants of the PWWP, no back injuries to PWWP participants, PWWP participants reported they felt ready to work, were more aware of their bodies, felt less likely to suffer a back injury, and felt a sense of satisfaction by doing something good for themselves.
Specific back exercises in a PWWP and as part of a warm-up before a work-out include: repetitions of lateral trunk flexion, repetitions and/or static contractions of scapular adduction, hip circles, circumduction of sacrum, standing McKenzie exercises (standing back extension), “cat-camel” with hands on bent knees, and isometric bracing of the abdominal muscles.
Al-Salameen, A.H., Abugad, H.A., and Al-Otaibi, S.T. (2019) Low Back Pain among Workers in a Paint Factory. Saudi Journal of Medicine and Medical Sciences, 7(1):33-39.
Andersson , G.B.J., L.J. Fine, and B.A. Silverstein, (1995). Musculoskeletal Disorders. Ed: Levy, B.S. & Wegman, D.H. Occupational Health: Recognizing and Preventing Work-Related Disease. Little, Brown and Company, Boston.
Bigos, S.J., et al., (1992). A longitudinal, prospective study of industrial back injury reporting. Clinical Orthopaedics and Related Disorders, 279: 21-34.
Bracko, M.R. (1998). Fit for duty, Canadian Occupational Safety, May/June: 20-23.
Hanchak, N.A., Murray, J.F., Hirsch, A., McDermott, P.D., and Schlackman, N. (1996). USQA health profile database as a tool for health plan quality improvement. Managed Care Quarterly. 4:58–69.
Hilyer, J.C., et al., (1990) A Flexibility Intervention to Reduce the Incidence & Severity of Joint Injuries Among Municipal Firefighters, Journal of Occupational Medicine., 32(7):631-637.
Licciardone, J.C. (2008). The epidemiology and medical management of low back pain during ambulatory medical care visits in the United States. Osteopathic Medicine and Primary Care. 2: 11.
McGill, S.M. (2001) Low back stability: From formal description to issues for performance and rehabilitation. Exercise and Sports Science Reviews. 29(1): 26-31.
McGill, S.M. (1997). The biomechanics of low back injury: Implications on current practice in industry and the clinic. Journal of Biomechanics, 30(5): 465-475.
Parreira, P. et al., (2018). Risk factors for low back pain and sciatica: an umbrella review. Spine Journal, 18(9):1715-1721
Videman, T., M. Nurminen, and Troup, J.D.G. (1990). Lumbar spinal pathology in cadaveric material in relation to history of back pain, occupation and physical loading, Spine, 15: 728-740.