Arizona Court of Appeals Division One Holds that Higher Showing of Causation Required to Reopen a Workers’ Compensation Claim Based on a Subsequent Injury Does Not Apply Where the Subsequent Injury Is a Deterioration Linked to the Initial Injury.

Employee was a stonemason who injured his knee on the job and received workers’ compensation benefits. After he returned to work, his knee gave out and he quit working. He filed a petition to reopen his prior claim, alleging a new, additional, and/or previously undisclosed condition relating to that claim. Following a hearing, the administrative law judge (ALJ) granted reopening and summarily affirmed the award upon administrative review. Employer filed a special action, arguing that the ALJ erred by reopening the case without proof that the subsequent injury was a “direct and natural result” of the previous injury with a “substantial causal relationship” to the previous injury.

On special action review, the Arizona Court of Appeals affirmed the award. The court held that the higher showing of causation required under the “compensable consequences” cases relied upon by Employer was not required under the facts. Because Employee’s subsequent injury was the result of a gradual deterioration of the condition that caused the original injury, Employee was entitled to reopen the prior claim upon establishing a new, additional, or previously undiscovered condition with a causal link to the initial injury. See A.R.S. § 23-1061(H). The “compensable consequences” doctrine, with its more stringent required proof of causation, applies only when the subsequent injury manifests after a distinct event, accident or disease subsequent to the original injury.

Judge Johnsen wrote the opinion; Judges Thompson and Ehrlich concurred.