In South Abington Township v. Workers' Compensation Appeal Board (Becker), 831 A.2d 175 (Pa. Cmwlth. 2003), the Court recognized that apportionment of liability is permitted under section 322 of the Workers' Compensation Act (Act) in either of two scenarios: The first is that represented by Franklin Steel Co. v. Workmen's Compensation Appeal Board (Clark), 665 A.2d 1310 (Pa. Cmwlth. 1995), in which two separate work-related injuries result in two entirely separate medically disabling conditions, both of which combined to cause total disability, or lack of earning power. As our Supreme Court has noted in discussing Franklin Steel, "Where it is impossible to determine which injury caused a claimant's total disability, it is reasonable to make both insurers contribute to the claimant's benefit package." L.E. Smith Glass Co. v. Workers' Comp. Appeal Bd. (Clawson), 571 Pa. 594, 600, 813 A.2d 634, 638 (2002). The other situation in which apportionment has been recognized is where an initial workplace injury leads to a medical condition causing a partial disability, or impairment of earning power, and then a second workplace injury results in a total loss of earning power.... This is the situation in Trenton China Pottery v. Workers' Compensation Appeal Board, 773 A.2d 1265 (Pa. Cmwlth. 2001) South Abington at 180. The Court distinguished these scenarios from the situation where apportionment is not warranted, i.e., "where a claimant has returned to work after his first injury and then a worsening of his ongoing medical impairment causes renewed disability." Id. at 181. The Court then stated: In other words, while we allocate liability for benefits based on relative contributions to claimant's total lack of earning power, as in Franklin Steel or Trenton China Pottery, neither the Act nor our case law has ever attempted to allocate responsibility based upon relative contributions of separate injuries to a single disabling medical condition. Id. at 182.