OPINION
Appellant seeks reversal of the trial court’s judgment ordering it to pay workers’ compensation benefits for total and permanent disability to appellee, George B. Taylor, for a back injury he incurred while in the course and scope of his employment with the Goodyear Tire and Rubber Company-
In its sole point of error, appellant complains of the refusal by the trial court to submit its tendered instruction to the jury relating to “sole cause.” 1 Appellant contended that a pre-existing back condition, rather than the injury sustained in the slip- and-fall accident, was causing appellee’s current disability. Medical testimony in support of both parties was presented at trial from depositions to the effect that appellee is currently suffering from a long-term degenerative spine condition called “stenosis,” defined as a narrowing or closing down of the canal carrying the spinal cord. Appellant contends that the trial court abused its discretion in refusing the “sole cause” instruction, as the evidence supported submission of this instruction, and that its refusal deprived appellant of a legal defense to appellee’s claim by not allowing the jury to consider its defense of “sole cause.”
Prior to the 1973 amendment to Rule 277 of the Texas Rules of Civil Procedure, “sole cause” was submitted to the jury as a special issue, when the pleadings and evidence raised the point.
Webb v. Western Casualty and Surety Co.,
An “inferential rebuttal” has been defined as an issue which disproves the existence of an essential element submitted in another issue.
Select Ins. Co. v. Boucher,
In order to determine whether an abuse of discretion was committed, we must examine the inferential rebuttal cases to determine what was required in order for a party to have been entitled to such instruction. These cases reveal that the requested instruction should be given only if there are pleadings raising the issue and there is
some
evidence presented at the trial in support thereof. In
Webb, supra,
the Supreme Court found that
no
evidence was presented to raise the issue of “sole cause.” The Court said that no evidence was raised when the doctor, testifying about a pre-existing condition being the only cause of a heart attack, said it was
possible,
but highly
unlikely. Webb,
Ample evidence was presented in the doctors’ testimony to raise “sole cause.” One doctor testified that it was only possible, not probable, that the problems appellee continued to have could have resulted only from the degenerative spine condition rather than from his industrial injury. Another physician testified that he thought
the basic disease was one of degeneration and that his fall probably caused — again, I didn’t see him at the time — but probably caused some acute muscular thing which prevented him from working at the time but certainly didn’t cause the extensive basic disease which is present.
The same doctor further testified ... "most, if not all, of his symptoms are secondary to a degenerative problem in the spine rather than a traumatic one.” A third doctor testified that based on a reasonable medical probability, the stenosis ap-pellee was suffering from was not caused by the fall he had taken.
We hold that it is the trial judge’s duty to determine whether the doctrine of “sole cause” has been raised by the evidence admitted in the case. If he finds that there is such evidence tending to establish the necessary elements of the doctrine, then it is clearly his duty to submit such explanatory instructions as are proper to enable the jury to render a just verdict. See
Erickson v. Deayala,
Appellee argues that any error, if committed, was harmless under Rule 434 Tex.R.Civ.P. and cured by appellant’s extensive final argument before the jury that it was the stenosis and not the injury which caused the appellee’s incapacity. We cannot agree because the jury did not get the benefit of the definition of “sole cause” in its charge. Such definition would have given the jury a more complete perspective of how the case should be analyzed, as the existence of “sole cause” negates the existence of any “producing cause.” In making the determination whether appellant has been harmed by the error complained of under Riile 434, the reviewing court must consider the record
as a whole. Texas Power and Light Co. v. Hering,
In considering the record as a whole, we find that the trial court’s failure to give the requested instruction was an abuse of discretion and deprived the appellant of a defense to the appellee’s claim. Appellant’s final jury argument did not cure the error. The definition of “sole cause” was necessary to enable the jury to render a proper, well balanced, and just verdict.
Appellant’s point of error is sustained, and the cause is remanded for a new trial.
Notes
. There may be more than one producing cause of an incapacity, but there can be only one sole cause. If an injury or condition was the sole cause of an incapacity, then no other injury or condition could have been a producing cause. STATE BAR OF TEXAS, TEXAS PATTERN JURYCHARGES § 25.01 (Supp.1976).
