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CA Work Comp Appeals Board Rules on Industrial Injury with Preexisting Condition

work-accident-attorney-los-angelesIn California, people who suffer work-related injuries that are permanently disabling may recover disability compensation from their employers’ workers’ compensation insurance. However, if a part of the disability is caused by an underlying condition, the law requires that the Workers’ Compensation Appeals Board apportions the cause between the work injury and the underlying condition. City of Petaluma v. Workers’ Compensation Appeals Board, Cal. Ct. App., Case No. A153811 dealt with a case in which a police officer had an asymptomatic underlying condition that was triggered by a workplace injury. The California Court of Appeals looked at when apportionment is required and when it is not.

Factual and procedural background

Aaron Lindh worked as a police officer for the City of Petaluma. During a canine training course, Lindh received three to six blows to the left side of his head. Following the injury, Lindh began suffering severe headaches that lasted for several hours. A month following the work-related injury accident, Lindh lost nearly all of the vision in his left eye. Lindh saw two different doctors. Neither of the doctors attributed his vision loss to the work accident. Lindh submitted a claim for workers’ compensation for his disability.

A neurologist who was the qualified medical examiner testified that Lindh suffered from a previously asymptomatic condition of defective blood flow to his left eye. He testified that Lindh was not disabled before he received the blows to his head and that he may have retained most of the vision in his left eye if he had not been struck. However, he also testified that the underlying condition may have caused a vision loss even if Lindh had not been injured. The doctor then apportioned the cause of Lindh’s injury and resulting disability as 85 percent to the underlying condition and 15 percent to the work-related incident. The administrative law judge denied the apportionment and instead found that Lindh suffered a 40 percent permanent disability as was stipulated by the parties. The City of Petaluma appealed, arguing that the court should have apportioned the cause between the underlying medical condition and the work accident as the QME had testified. The California Workers’ Compensation Appeals Board affirmed the ALJ’s decision and ruled that Lindh’s disability was not subject to apportionment. The city appealed to the California Court of Appeals, arguing that apportionment was required in the case.

Issue: Whether an asymptomatic underlying condition that could potentially never present symptoms requires apportionment when it contributes to the cause of the disability?

In California, administrative law judges apportion the causes of a work-related disability between any preexisting or underlying conditions that the workers have and the actual workplace injury. When the cause is apportioned, the workers will receive the percentage that is attributed to workplace accidents but not to the underlying conditions.

Rule: QMEs must include an apportionment determination in their reports that state the percentage of the cause of the disability to attribute to the work accidents and the percentage that should be attributed to preexisting conditions or prior incidents.

Before 2004, administrative law judges were prohibited from apportioning claims based on causation. This meant that workers who had preexisting conditions that were aggravated by work-related accidents could recover compensation for their entire disability rating instead of just the portion that was attributable to the work accidents. However, the state legislature changed the law in 2004. The new law states that doctors who serve as QMEs must include apportionment determinations in their reports when industrial injuries result from a combination of preexisting conditions and workplace accidents. If they don’t apportion the causes, they must include statements about why the did not.


In California, people who suffer an industrial injury while they are on the job may recover several types of remedies, as we have previously discussed. Workers may be entitled to compensation for their related medical expenses, temporary disability payments while they are out of work, a permanent disability award that is calculated according to the residual injury that remains in the affected body area, and a supplemental job displacement benefit if they cannot perform the functions of their prior jobs.

Lindh’s case involves looking at his permanent disability rating and determining whether it should have been apportioned. The court first reviewed the statutory changes that were made by the California Legislature. The statutes provided that doctors should include a statement of apportionment in their reports, and the apportionment determination must be based on sound medical evidence. The statutes further state that the employers are liable only for the portion of the disability that is directly attributed to the workplace accidents and not for the portion that is attributed to other causes. Another statute specifies that the other factors include preexisting conditions, including those that are asymptomatic.

The court then reviewed other cases that dealt with apportionment after the legislative changes. The court found multiple cases in which the court found that apportionment could be based on asymptomatic conditions and non-industrial sources.

Lindh argued that the QME’s testimony did not amount to substantial medical evidence. The court examined the doctor’s testimony and found that the doctor was clear in his assessment that the disability was caused by both the underlying condition and the work accident. The court also found that the doctor clearly testified that Lindh could have maintained his vision for the rest of his life or that he could have suffered a loss of vision even if he had not suffered blows to his head because of the underlying condition. Finally, Lindh argued that apportionment is only required when there is medical evidence that the underlying condition would result in the disability. However, the court rejected this argument because it reflected the state of the law prior to the 2004 statutory changes.


The court overruled the California Workers’ Compensation Appeals Board and directed it to apportion Lindh’s permanent disability according to the doctor’s testimony. Because only 15 percent of his injury could be attributed to the workplace injury, and he was considered to be 40 percent permanently disabled, this meant that he would receive a substantially lower permanent disability award.

Contact an experienced Los Angeles personal injury lawyer

If you have been injured in a workplace accident and have learned that you have a preexisting condition that may have contributed to your disability, you may need legal help. Contact the Law Offices of Steven M. Sweat today to learn more about your rights to workers’ compensation benefits.


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