See Macklanburg-Duncan Co. v. Edwards, 1957 OK 116, 311 P.2d 250, 255. See also Decker v. Oklahoma State University, 1988 OK 152, 766 P.2d 1371, 1374; G.T. Harvey Co. v. Steele, 1959 OK 220, 347 P.2d 802, 804. Rankin v. Ford Motor Company, 1996 OK 94, 925 P.2d 39, 40-41 (claimant's wage rate is that which was in effect on the date claimant first became aware of his (her) cumulative-trauma injury; this is so because that is the time of the injury within the meaning of 85 O.S.Supp. 1994 § 21[ 85-21]; see also Coy, supra, note 4 at 747; Tullis, supra note 4 at 903.

The opinion of Dr. M. suffices as competent evidence there were physical or pathological changes to the elbow caused by cumulative trauma at work. Cases cited by TRW to support its argument objective physical or pathologic changes must be shown are Refrigerated Transport, Inc. v. Creek, 590 P.2d 197 (Okla. 1979); Transcon Lines, Inc. v. Curtis, 402 P.2d 269 (Okla. 1965); Crest Building Corp. v. Lowe, 388 P.2d 512 (Okla. 1964); G.T. Harvey Co. v. Steele, 347 P.2d 802 (Okla. 1959); Consolidated Gas Utilities Corp. v. Jeter, 205 Okla. 471, 238 P.2d 804 (Okla. 1951); Tyson Foods, Inc. v. Guthrie, 773 P.2d 769 (Okla. Ct. App. 1989). Osteoarthritic can be caused by trauma and other conditions [STEDMAN'S MEDICAL DICTIONARY 1107 (25TH ed. 1990)], some unrelated to either singular or cumulative trauma, as acknowledged by Dr. M. at his deposition.

We take note of four cases handed down by this Court wherein a necessary and vital element to support a workmen's compensation claim under workmen's compensation statutes as then constituted depended upon hearsay evidence. Those cases are: Special Indemnity Fund v. Knight, 201 Okla. 24, 200 P.2d 766 (1948); Terry Motor Company v. Mixon, Okla., 336 P.2d 351 (1959); G.T. Harvey Company v. Steele, Okla., 347 P.2d 802 (1959); and Southwestern Bell Telephone Company v. Nelson, Okla., 384 P.2d 914 (1963). In each case, we held that hearsay evidence was inadmissible.

1965); Crest Bldg. Corp. v. Lowe, 388 P.2d 512 (Okla. 1964); G.T. Harvey Co. v. Steele, 347 P.2d 802 (Okla. 1959); Macklanburg-Duncan v. Edwards, 311 P.2d 250 (Okla. 1957).Oklahoma City v. Schoonover, 535 P.2d 688 (Okla.

Respondents contend that the finding of disability was based on incompetent medical testimony, arguing that the medical opinion was not made with "reasonable medical certainty." Respondents cite Garr-Wooley Oil Co. v. Yeargin, Okla., 355 P.2d 410, and G.T. Harvey Co. v. Steele, Okla., 347 P.2d 802, in support of this proposition. In these two cases, the medical opinion failed to connect the disability complained of with an accidental injury as contemplated by the Workmen's Compensation Act.

We are committed to the rule that where there is an entire absence of competent evidence to support the award of the State Industrial Court, it will be vacated as a matter of law. Ada Coca-Cola Bottling Company v. Snead, Okla., 364 P.2d 696; Harvey Company v. Steele, Okla., 347 P.2d 802; Phillips Petroleum Company v. Eaves, 200 Okla. 21, 190 P.2d 462. The award of the State Industrial Court is vacated and this cause is remanded to such court with directions to enter an order in favor of the respondent, City of Oklahoma City, denying award.

We are committed to the rule that where there is an entire absence of competent evidence to support the award of the State Industrial Court, it will be vacated as a matter of law. Ada Coca-Cola Bottling Co. v. Snead, Okla., 364 P.2d 696; Harvey Co. v. Steele, Okla., 347 P.2d 802; Phillips Petroleum Co. v. Eaves, 200 Okla. 21, 190 P.2d 462. The award of the State Industrial Court is vacated and this cause is remanded to such court with directions to enter an order in favor of the respondent.

We have also ruled that an accidental injury within the meaning of the Workmen's Compensation Act need not have resulted from one particular event, but may be the cumulative effect of trauma occurring at different times over an extended period. G.T. Harvey Company v. Steele, Okla., 347 P.2d 802; Acme Material Company v. Wheeler, Okla., 278 P.2d 234. From the tenor of Dr. H's statement that "repeated insults to his back with heavy lifting, awkward positioning working underneath trucks and that sort of thing has triggered off these complaints" that "he reports that on August 6, 1963, he had a recurrence of a problem in his back that had been intermittent during the last several months," we feel his intent to be that the occurrence on August 6, 1963, was the accidental injury that caused claimant's present back condition.

Kelley v. Enid Terminal Elevators, Okla., 372 P.2d 589; Ben Hur Coal Company v. Orum, Okla., 366 P.2d 919. An accidental injury within the meaning of the Workmen's Compensation Act need not be attributable to one particular event, but may arise progressively from the cumulative effect of a series of exertion episodes. See Macklanburg-Duncan Co. v. Edwards, Okla., 311 P.2d 250; Acme Material Company v. Wheeler, Okla., 278 P.2d 234; Calhoun Const. Co. v. Sexton, Okla., 288 P.2d 705, and G.T. Harvey Company v. Steele, Okla., 347 P.2d 802, 804. According to Dr. S, claimant's expert witness, "there can be little doubt" but that claimant's coronary attack was precipitated by "prolonged working period," "stress of long travel," "protracted driving" and lack of (adequate) sleep" between October 29, and November 3.

While it is not disputed that respondent was doing the work which he states produced the accidental injury, petitioners in their argument give particular stress to their contention that respondent was merely doing his usual and ordinary work; that since nothing unusual happened which is evident from the fact that pain did not become prevalent until two days after respondent quit doing this particular work, there is no accidental injury. In the case of G.T. Harvey Company v. Steele, Okla., 347 P.2d 802, 804, we said: "This court has held that an accidental injury within the meaning of the Workmen's Compensation Act need not have resulted from one particular event, but may be the cumulative effect of trauma occurring at different times over an extended period.