and [his] work activity.” Johme, 366 S.W.3d at 510. Borrowing from Miller, Gleason’s “injuries were worsened ... due to being in an unsafe location due to his employment. He was [working on the top of a railcar when he happened to fall 20-25 feet].” 287 S.W.3d at 674. In contrast to the outcome in Miller, Gleason fell 20 to 25 feet to the ground because of his required work activity. Id. It was thus not necessary for Gleason to establish why he fell because he had already established that he “was exposed to an unusual risk of injury that was not shared by the general public.” Porter, 402 S.W.3d at 174 (emphasis added). The Second Injury Fund argues that unless we require claimants to prove wh jury No.: 06-104584, 2009 WL 1719443, at *8 (Labor & Indus. Relations Comm’n June 16, 2009) (<HOLDING>). Here, the Second Injury Fund neither alleged,
holding that the exclusion from category of compensable injuries of an injury resulting directly or indirectly from idiopathic causes is in the nature of an affirmative defense to employer and that it was not the claimants burden to prove an injury was not idiopathic but instead the employers burden to prove that it was holding that it is the claimants burden to show that the injury was the result of an accident that not only arose in the course of the employment but that it also grew out of or resulted from the employment holding that the burden rests upon the party seeking benefits to prove the injury sustained was the result of an accident arising out of and in the course of employment and the rule of liberal construction is not a substitute for the claimants burden of establishing his claim by a preponderance of the evidence holding burden of proof is on one asserting an affirmative defense holding that the issue of whether the plaintiffs claim was barred by an intervening cause was not an affirmative defense but merely an assertion that the plaintiff cannot prove a necessary element of its claim