COMMONWEALTH OF MASSACHUSETTS
DEPARTMENT OF INDUSTRIAL ACCIDENTS
Employee: Gardy Gelin
Employer:Vinny Testa's Restaurant
Insurer: Royal Insurance Co.
Employer: Finbar's Pub, LLC
Insurer: Professional Liability Insurance Co.
Employer: Personnel People
Insurer: American Zurich Insurance Co.
Employer: Ocean State Job Lot of Norwood, LLC
Insurer: Federal Insurance Co.
Employer: Reebok International, Ltd.
Self-insurer: Reebok International, Ltd.
Employer: Panera Bread
Insurer: Commerce and Industry Insurance
Employer: Lambert Brothers
Insurer: Massachusetts Retail Merchants SIG
Board Nos.: 041268-03, 049498-03, 046329-04, 035068-05, 000003- 06, 000004-06, 000068-06, 015947-06
REVIEWING BOARD DECISION
(Judges Fabricant, Costigan and Horan)
Karen Seward, Esq., for the employee
William R. Trainor, Esq., for Royal Insurance Co.
Ellen Harrington Sullivan, Esq., and Daniel W. Gracey, Esq.,
for Professsional Liability Insurance Co.
Joseph R. Conte, Esq., and Sheila Cunningham, Esq., for Federal Insurance Co.
Mark J. Kelly, Esq., for American Zurich Insurance Co.
Amy Scarborough, Esq., for Reebok International
Mark H. Likoff, Esq., and Wayne A. Gallo, Esq., for Commerce and Industry
Richard N. Curtin, Esq., for Massachusetts Retail Merchants SIG
FABRICANT, J. The employee appeals from a decision in which the administrative judge concluded that no workplace injury had occurred, and denied and dismissed his claim for weekly workers' compensation benefits.  The employee correctly argues that Royal Insurance Company (Royal) accepted liability for his February 2003 work injury when it failed to appeal a different administrative judge's § 10A conference order for medical benefits. We therefore vacate the decision, and recommit the case for a new hearing. 
The employee worked as a dishwasher at Vinny Testa's Restaurant. Sometime in early February 2003, he developed bilateral wrist pain while carrying heavy stacks of plates. He did not report an injury to the employer, and his employment terminated on or about February 7, 2003. (Dec. 4-5.)
The employee subsequently filed a claim for workers' compensation benefits against Royal, which resulted in a conference order for § 30 medical benefits for his wrists. Although the decision states that both parties appealed from this conference order, (Dec. 2), the parties agree that, in fact, this order was appealed only by the employee. (Employee br. 2, Royal br. 1, 2.) Because the insurer's failure to appeal is tantamount to acceptance of liability pursuant to G. L. c. 152, § 10A(3) , the judge's failure to find that a work place injury occurred, within the meaning of the act, is error and must be reversed. (Dec. 9.)
Royal argues that this error is harmless and asserts that the February 2003 injury was a mere "flare up" of a pre-existing congenital condition that resulted in no lost time from work. Based on the impartial medical physician's opinion that the employee had a pre-existing congenital wrist condition that was exacerbated by his work as a dishwasher, Royal raised § 1(7A) "a major" causation as part of its defense. (Dec. 7.) The impartial physician specifically opined that the work contribution to the employee's resultant disability was "moderately significant," which he further defined as "fifty percent or less." (Dec. 8.) We disagree with the insurer that, as a matter of law, the impartial physician's opinion cannot satisfy the § 1(7A) standard of "a major" causation. See Siano v. Specialty Bolt & Screw, Inc., 16 Mass. Workers' Comp. Rep. 237, 240 (2002) ("A major cause is an important, a serious, a moderately significant cause.") We therefore conclude that the judge's error in denying liability for the accepted February 2003 workplace injury was not harmless, nor was his resulting failure to perform the requisite causation analysis under § 1(7A).
Accordingly, we reverse the decision, and recommit the case for a new hearing, at which the employee's entitlement to weekly benefits, if any, shall be adjudicated against Royal and all successive insurers involved in the original litigation.
We transfer the case to the senior judge for reassignment to an administrative judge for a hearing de novo.
Bernard W. Fabricant
Administrative Law Judge
Patricia A. Costigan
Administrative Law Judge
Mark D. Horan
Administrative Law Judge
Filed: September 17, 2008
 We note that the case was tried against multiple successive insurers joined as a result of the employee's motion filed subsequent to the parties' appeal of the October 22, 2004 conference order granting medical benefits to the employee pursuant to §§13 and 30. Only one successive insurer filed a brief responding to the employee's appeal. Given our disposition of the employee's appeal, infra, the successive insurers will again be parties to the proceedings. See Borstel's Case, 307 Mass. 24, 26-27 (1940).
 As the administrative judge who wrote the decision no longer serves on the industrial accident board, the proceedings on recommittal must be de novo.
 General Laws c, 152, § 10A(3), provides, in pertinent part:
Any party aggrieved by an order of an administrative judge shall have fourteen days from the filing date of such order within which to file an appeal for a hearing pursuant to section eleven. Such hearing shall be held within twenty-eight days of the department's receipt of such appeal.
Failure to file a timely appeal or withdrawal of a timely appeal shall be deemed acceptance of the administrative judge's order and findings. . . .