A.C. Lawrence Leather Co., 559 A.2d 776, 777 (Me.1989). Mathieu further contends that the Board’s summary decision to decline a review in all of the cases pending before the Appellate Division at the time that it went out of existence on January 1, 1994, was a violation of its statutory authority, 39-A M.R.SA,. § 320 (Supp.1994), and a violation of his constitutional rights of due process and equal protection. P.L.1991, ch. 885, § A-10(2). We disagree. The Commissioner applied the correct legal standard in denying Mathieu’s petition for restoration. The Board’s summary denial of administrative review did not contravene its statutory authority or violate Mathieu’s constitutional right of due process and equal protection. We therefore affirm the decisions of the Commission and the Board.
Mathieu suffered a work-related back injury on July 25, 1988, while employed as a heavy equipment and fork-lift operator at Bath Iron Works. Mathieu returned to work as an inventory clerk in 1989 at reduced pay and in 1990 was awarded 31% partial incapacity benefits. On March 2, 1991, Mathieu injured his ankle in a nonwork-related car accident and did not return to light-duty work until August 1991. Mathieu continued, however, to receive 31% incapacity benefits during his absence and after he returned to work following the car accident. Contending that the ear accident injury aggravated or otherwise combined with his prior back injury, Mathieu filed a petition for restoration seeking total incapacity benefits. The Commission concluded that Mathieu “was totally incapacitated solely as a result of the motor vehicle accident during the period of March 2, 1991 through August 5, 1991, which acted as an independent intervening cause of the employee’s incapacity during that time.” It denied Mathieu’s petition for restoration and his motion for findings of fact.
Mathieu appealed to the former Appellate Division, which failed to resolve his appeal prior to going out of existence on January 1, 1994. The Board declined to review any of the approximately 196 unresolved appeals pending with the Division on January 1,1994. 39-A M.R.SA § 320 (Supp.1994); P.L.1991, ch. 885, § A-10(2). We granted Mathieu’s petition for appellate review pursuant to 39-A M.R.SA. § 322 (Supp.1994).
I.
Mathieu contends that the doctrine of “independent intervening cause” is a tort law doctrine that does not apply in workers’ compensation cases. Our decisions make clear that the presence of an intervening independent cause of incapacity will not remove the employer’s liability for workers’ compensation as long as the prior injury remains a “cause” of the employee’s ongoing condition. Brackett, 559 A.2d at 778; Smith v. Dexter Oil Co., 408 A.2d 1014, 1015-16 (Me.1979); Richardson v. Robbins Lumber, Inc., 379 A.2d 380, 383 (Me.1977). Mathieu bore the burden of proof on his petition for restoration to show that his short-term total incapacity was caused, at least in part, by a work-related injury. Although the Commissioner referred to the ankle injury as an “independent intervening cause,” the decision read as a whole suggests that because Math-ieu “was totally incapacitated solely as a result of the motor vehicle accident during the period of March 2, 1991 through August 5,1991,” his prior work injury ceased to be a “cause” of his incapacity during the period of his totally debilitating ankle condition.
We give deference to the factual findings of the Commission, particularly when those findings require an evaluation of medical evidence. Smith v. Great Northern Paper, Inc., 636 A.2d 438, 439 (Me.1994); McKenzie v. C.F. Hathaway, Co., 415 A.2d 252, 253 (Me.1980). Contrary to Mathieu’s assertion, there is competent evidence in the record to support the conclusion that Math-ieu’s work-related and nonwork-related injuries were causally unrelated and that his lost time from work was solely a result of his ankle injury and subsequent ankle surgery. Based on this evidence, the Commissioner reasonably may have concluded that Mathieu had not met his burden to show that his prior back injury was a cause of his short-term total incapacity.