“Preexisting Condition” Redefined In New Workers’ Comp Law

Workers’ Compensation claims involving injuries on or after January 1, 2002, have been subject to changes in the law, including a new definition of “pre-existing condition.”


Generally, a “preexisting condition” is a medical condition which a worker had prior to a claimed work injury or occupational disease, and which contributed to it. The definition is important since such conditions must be taken into account in determining whether the workers’ compensation claim is compensable.

The primary changes in the new definition are: 1) that the purported preexisting condition now must “contribute to” the disability or need for treatment, not just “predispose” the worker to disability or need for treatment; and 2) there must have been diagnosis or medical services for the preexisting condition before the claimed work injury, unless the pre-existing condition is arthritis or an arthritic condition. So, the diagnosis and treatment of the alleged “preexisting condition” must have preceded: the initial injury, the onset of the new medical condition claimed, or the onset of the worsened condition, in “aggravation” claims.

The requirement of a prior diagnosis or obtaining of medical services for symptoms is significant. Now, if a worker suffers a heart attack on the job and no heart condition had ever been diagnosed or treated, then a heart condition may not, by definition, be considered a “preexisting condition” for purposes of opposing the worker’s injury claim.

The “arthritis exception” will probably stimulate medical debate: Is degenerative disc disease arthritis or an arthritic condition or is it just a normal state of human existence?

Since workers’ compensation benefits are available for either an “industrial injury” (a discrete injurious event) or an “occupational disease” (conditions usually brought on by workplace exposure over time), the definition of preexisting condition is now separated into sections addressing each. The requirements are slightly different.

For example, the requirement of a diagnosis or medical services or treatment preceding the claimed condition appears in the industrial injury section, but does NOT appear under the definition of “preexisting condition” for occupational disease claims. Otherwise, the definition for preexisting condition under each section is the same:

“Preexisting condition means, …, any injury, disease, congenital abnormality, personality disorder or similar condition that contributes to disability or need for treatment.”

The new definition emphatically requires that the alleged preexisting condition contribute to disability or need for treatment. The new law not only eliminated the words “or predisposes” (“…the worker to disability or need for treatment…”); but the new law also explicitly explains that a preexisting condition does not “contribute to” disability or need for treatment, “if the condition merely renders the worker more susceptible to the injury,” in industrial injury claims.

By eliminating conditions which only predispose a worker to disability or need for treatment or only render the worker more susceptible to injury, the legislature appears to intend that any alleged “preexisting condition” must contribute in an active causal way to the actual claimed injury or occupational disease.

We hope that by eliminating conditions which only predispose a worker to disability or need for treatment, this new law will result in fewer claims being denied on the basis of a worker’s gender, height, obesity, body habitus, type of acromion, shape of wrist, and other peculiar anatomical features.

Furthermore, it would appear that a fair reading of the statute would allow that even arthritic conditions which merely predispose a worker to disability (as opposed to being directly causative) are not preexisting conditions that weigh against the worker.

As to injury claims, the new law also moves the burden of proof to the employer in cases where the work injury combined with a preexisting condition.

The “burden of proof” refers to which party in a dispute has the responsibility to present evidence to prove a particular point. The worker has the responsibility to prove he/she suffered a compensable work injury or occupational disease. However, if the compensable injury combines with a preexisting condition, the resulting combined condition is compensable only as long as the injury is the major contributing cause of the disability or need for treatment. In such cases, it is the employer’s responsibility (burden) to prove that the compensable injury is no longer the major contributing cause of the disability or need for treatment of the combined condition.

The new law explicitly states that this shifting of the burden of proof only occurs in injury claims and does not apply to occupational disease claims.

An “occupational disease” is any disease or infection arising out of employment and caused by substances or activities the worker is subject to or exposed to during regular actual employment, and not ordinarily exposed to outside of employment. The disease or infection must require medical services or result in disability or death. It may come from ingesting, inhaling, absorbing or contacting dust, fumes, vapors, gases, radiation or other substances. It may be a mental disorder, sudden or gradual in onset. It may be a series of traumatic events or occurrences (including the multiple “micro-traumas” of repetitious physical activities).

Again, occupational disease claims have a different legal status than injuries as relates to preexisting conditions. There is no requirement for diagnosis or treatment of the preexisting condition preceding the onset of the occupational disease. Also, the employer’s burden of proof in combined condition claims does not pertain to occupational disease claims . That is, in occupational disease claims, employers are not required to prove compensable injuries are no longer the major contributing cause of the disability or need for treatment of combined conditions.

In summary, the new law tightens up the standards for a preexisting condition, 1) by confining it only to those conditions which contribute to the injury or disease; and 2) by requiring its diagnosis or treatment prior to a claimed injury, worsened (aggravated) condition or new medical condition, except when the preexisting condition is an arthritic condition. Also, the new law codifies court rulings that the employer is responsible to prove the compensable injury is no longer the major cause in combined condition cases. Finally, the new law clarifies how injuries and occupational diseases are to be treated differently vis a vis preexisting condition situations.

We hope this explanation of the new law is helpful to you when you are called upon for your medical opinion in cases where the status of a worker’s injury or disease claim is affected by the alleged presence of a preexisting condition.

This article was prepared by Arthur W. Stevens III and Peter E. Yeager