OPINION
WOODARD, Justice.This is an appeal from a summary judgment in favor of the physician in a malpractice claim. We affirm.
Ms. Hicks suffered a herniated disk that was operated upon in December of 1988. Dr. Howard Lee, the surgeon, mistakenly incised into the wrong vertebral level. Certain complications, including spinal fluid leakage, were effectuated in the process. This required surgical correction. The originally contemplated surgery was accomplished at a some five inch lower level. Dr. Canessa was the anesthesiologist at the misdirected surgery. The surgeon, the assistant surgeon, the hospital and Dr. Canessa were sued. Dr. Canessa’s case was severed and favored by a summary judgment.
The thrust of the Appellant’s argument for error is that the surgery could not begin without the anesthesiologist’s expressed permission to proceed. At the time such authorization was given, Dr. Canessa did not make certain the assistant surgeon was present. The absence of a assistant surgeon is a violation of the hospital policies, and, therefore, is evidence of a lack of proper medical standard of care. The absence of the assistant surgeon allowed the surgeon to misjudge the entry point and was a proximate cause of the injury.
There are four elements that must be proven to prevail on a medical malpractice cause of action: (1) a duty by the physician to act according to certain standards; (2) a breach of the applicable standard of care; (3) an injury; and (4) a causal connection between the breach of care and injury. White v. Wah, 789 S.W.2d 312, 315 (Tex.App.—Houston [1st Dist.] 1990, no writ).
*544Appellant presented the depositional testimony of Dr. Canessa that he gave the surgeon permission to proceed. The import of this evidence is that the anesthesiologist must make certain that the patient is properly positioned, stabilized and anesthetized to allow the operation to proceed. There is no inference from this evidence that the anesthesiologist is the superintendent of the surgery.
Hospital rules do not reflect the community standard of medical care. A particular institution might maintain a higher standard of care in its operations than the prevailing community standard. Hilzendager v. Methodist Hospital, 596 S.W.2d 284, 286 (Tex.Civ.App.—Houston [1st Dist.] 1980, no writ). Therefore, any hospital requirement that the assistant surgeon be present is not evidence of the standard of medical care.
In his affidavit, Dr. Canessa stated that to exercise the proper standard of care for an anesthesiologist under the circumstances, it is necessary to constantly monitor the patients vital signs and administrate the anesthetic apparatus. To constitute competent summary judgment proof, the medical expert’s testimony must be clear, positive and direct, otherwise credible, free from contradictions and inconsistencies and of a subject matter that the trier of fact must be guided by the opinion testimony of an expert. Tex.R.Civ.P. 166a(c). The evidence must also be such that it could have been readily controverted by the non-movant. Cedillo v. Jefferson, 802 S.W.2d 866 (Tex.App.—Houston [1st Dist.] 1991, writ denied). This testimony of Dr. Canessa is of a nature which could have been effectively countered by opposing evidence. The credibility of the deponent is not likely to be a dispositive factor in the resolution of the case. Casso v. Brand, 776 S.W.2d 551 (Tex.1989). In absence of controverting proof, summary judgment may be proper. Id.
A summary judgment is proper if the defendant’s summary judgment evidence shows at least one element of the plaintiff’s cause of action has been established conclusively against the plaintiff. Gray v. Bertrand, 723 S.W.2d 957, 958 (Tex.1987). The defendant/movant has established that there was no breach of standard of care.
Judgment of the trial court is affirmed.