A claimant attempting to establish a compensable, work-related injury must prove by a preponderance of the evidence the injury is medically distinguishable from a pre-existing nonwork-related condition in order to establish the existence of a “personal injury” under § 301(1) and entitlement to benefits. A symptom such as pain is evidence of injury, but does not, standing alone, conclusively establish the statutorily required causal connection to the workplace. Evidence of a symptom is insufficient to establish personal injury “arising out of and in the course of employment”. The court overruled several Court of Appeals opinions holding the aggravation of symptoms of a pre-existing condition is compensable without finding a work-related injury under § 301(1). The court also concluded it inappropriate to utilize the “liberal construction” standard when the issue being considered is the initial qualifying matter of whether the claimed injury falls within the WDCA regime. Reversed and remanded to the WCAC.

The dissenting justices concluded the majority holding reads into the statute a new test not required by the text of the statute, and would construe the statute liberally to hold an aggravation of symptoms may constitute a work-related injury compensable under the WDCA.

Dissenting separately, Justice Kelly would affirm the Court of Appeals decision and concluded the majority in its pronouncement on pain made new law by discounting pain and redefining “injury”, thereby altering the previous definition of the word “injury” under the act. Further, the statute should be liberally construed to grant rather than deny benefits.