Most people, excluding lawyers, are likely to tell you that it is an obvious fact that strenuous activity involving load on the back in occupations with heavy lifting, twisting, bending, and carrying will cause more back injuries. Athletes and medical professionals are less likely to make the injury causation assumption, and will respond that people who use their bodies correctly for physical work are actually in better physical condition, with fewer back injuries than workers with sedentary jobs sitting in front of a computer all day. Add to the discussion that back pain is prevalent in the general population, with 80% of Americans seeking treatment for low back pain at some time, and it is difficult to get a consensus as to what back injuries are work-related.
The AMA Guides to the Evaluation of Disease and Injury Causation by Melhorm and Ackerman, published in 2008 by the American Medical Association is a book dedicated primarily to assist health care providers when giving their opinion as to whether a condition is work-related or attributable to a specific event. The authors use the catch phrase "evidence-based' decision, and the book discusses the strengths and weaknesses of the available evidence considered reliable by experts in various medical specialties. The book cautions that because each state establishes case precedents and has its own laws, what is considered acceptable evidence can vary widely. A review of the Nevada Supreme Court decisions on low back injuries, does little to tell us where to neatly draw the line between a compensable low back injury and one that is not work-related.
Nevada workers' compensation benefits are limited to workers who have "injuries by accident" in the course and scope of their jobs and arising out of the job activity. The terms "injury" and "accident" have definitions in the law that do not always correlate well to real life situations, but whenever a worker must get involved in the legal process involving a claim, it's a good idea if he (and certainly his attorney), knows what Nevada legislators, adjusters, lawyers, hearings and appeals officers, and judges are looking at to determine whether someone has an industrial injury by accident, or whether the worker's condition might be within the definition of "occupational illness".
Injury is defined in Nevada law as "a sudden and tangible happening of a traumatic nature, producing an immediate or prompt result which is established by medical evidence". NRS 616A.265. This means that if an injured worker cannot identify when and where he or she felt a different kind of pain from a specific work activity at a particular point in time that caused the worker to need medical care very soon afterwards, the claim is likely to be denied as not satisfying the "injury by accident" requirements of the law. There haven't been any recent Nevada Supreme Court cases that help decide whether a low back problem can qualify as an occupational illness, and in general, at that time, if you can't describe an injury by accident, it isn't likely that your low back claim will be accepted.
Because of the wording of Nevada's laws defining "accident" and "injury", and because of the difficult causation requirements of the occupational disease statute, NRS 617.440, adjusters and lawyers want to know if you felt a pull, a pop, a sudden pain shooting down your leg, or an electrical type pain, and whether you thought you injured yourself when you were doing something that involved lifting, bending, or twisting at work.. They want to know how soon after feeling this distinct pain you felt the need to get medical care, and they want to know if you had already been seeing a doctor for back pain when this work incident occurred.
This makes it important for the injured worker to distinguish a specific injury by accident when completing the employer's accident form, and when filling out the C-4 Claim for Compensation form at the initial clinic. If someone calls me and asks for help in how to fill out the "Dated of Accident" box on the employer's accident form, or the C-4 Claim for Compensation form at the doctor's clinic, they are usually struggling with an ongoing or recurrent low back problem that has gotten worse at work without a specific incident that caused the increased symptoms. That is not to say that a worker cannot successfully establish a claim where he has preexisting degenerative conditions in his spine if he also has an injury on the job that now disables him and requires immediate medical care. This is just a tricky area of the law, because how the medical profession views what causes low back injuries and the reality of how people experience them don't always fit the statutory legal definitions. But legal definitions are used to decide who has a compensation claim, with the benefits it includes, or who must use health insurance for treatment and any vacation or sick days if disabled from working.
How your doctor describes how your injury occurred, your clinical symptoms, and how these factors relate to diagnostic tests play a major role in whether the adjuster accepts or denies your claim. Most injured workers think it is sufficient if they can show that they were working and living life fine before the date of injury, and after that date they were miserable, in pain, and disabled. There is a Latin term for this causal fallacy of reasoning. It is called post hoc ergo propter hoc- a fallacy that because one event occurs after another, there is a causal relationship between the two. Some of my clients have renamed this fallacy as "ignoring the obvious". Regardless, the attorney representing an injured worker with a denied low back claim will be looking at the causation question with an eye toward obtaining credible evidence to support that the problem is work-related.
The dfficulty in determining which low back pain workers get workers' compensation benefits versus those that don't is second only to the difficulty the medical providers have in determining what specifically is generating the pain in the low back.. The correlation between MRI findings of disc herniation and symptoms is relatively low, with many people showing disc herniations on MRI studies that don't have any back pain. The studies are simply not sufficient yet to support any of the several theories about what causes back pain. Thus far, they cannot reliable predict on the basis of radiographic evidence alone who will have back pain and who won't. Until then, it is crucial that a worker who feels he has a work-related low back injury, promptly report the specific activity that caused the recent pain and keep in mind the legal definitions.