Fahr v General Motors Corp., 478 Mich 922 (2007)
By an order issued on June 22, 2007, the Michigan Supreme Court addressed what is required to show a “medically distinguishable” condition pursuant to Rakestraw. The court stated that the WCAC erred by asserting that Rakestraw does not require a “pathological change in a pre-existing condition” for a Plaintiff to establish a work related injury has occurred. Instead, in the event that there is a pre-existing condition, Rakestraw clearly requires that the claimant must prove his work caused an injury that is medically distinguishable from the progression of the underlying pre existing condition. It must be shown that the pathology of that condition had changed and that cannot be accomplished by merely showing a worsening of symptoms.