In an article in the Pennsylvania Bar Association Quarterly, James A. Tinnyo, Esquire analyzes Acme Markets, Inc. v. WCAB (Purcell) to hold that an employee must be engaged in the furtherance of business when he suffers an injury off the premises that arises out of employment.
In the case, the Claimant labored heavily for years for the employer, but when his lumbar disk herniated, he was at home. What distinguishes this case from others is that the WCJ credited Claimant's doctor who opined the substantial cause of the herniated disk was the years of employment, not getting up off the floor after assembling a file cabinet for personal use.
Perhaps in this pre Daniels, two months post Wintermeyer case the Commonwealth Court didn't feel it could review the credibility determination.
One has to ask what the Court would have done if the Claimant, due to his degenerative condition accumulated from years at work, simply couldn't get up in the morning due to pain. If the Court would still deny the Claimant because he was at home (which is contrary to the heart attack cases Mr. Tinnyo cites) then a new precedent has been created.