KAUGER, J.:
¶ 1 We granted certiorari to address whether the evidentiary materials presented by the plaintiff were sufficient to withstand a motion for summary judgment. We hold that they were.
FACTS
¶ 2 On October 19, 2005, the plaintiff/appellant, Tracy R. Smith (Smith/patient), a field officer with the Oklahoma City Police Department, sought the care of the defendant/appellee, board-certified orthopedic surgeon, Dr. Robert Hines (Dr. Hines/doctor/surgeon), after suffering "problems" with her left knee and hearing it "pop" when she walked downstairs or squatted. Smith was diagnosed with chondromalacia, a softening of cartilage under the kneecap. After a course of "conservative treatment," the surgeon performed arthroscopic surgery on January 23, 2006.
¶ 3 It is undisputed that prior to the surgery Smith's problems were limited to her left knee and that her left thigh muscles functioned normally. The surgical notes state that there was an injection into the left knee, but they do not indicate that there was any nerve damage done to the left thigh during the procedure. Nevertheless, Smith alleged that following the procedure, she was approached by one of the postoperative nurses who indicated that there had been an "incident" during the operation which damaged her femoral nerve; and that the nurse allegedly told her that Dr. Hines would speak to her about the damage, but he never did.
¶ 4 Immediately after the surgery, it became apparent that the patient's left quadriceps (thigh) muscles were not functioning normally. Between January 24, 2006, and August 16, 2006, the patient saw the surgeon for eight post-surgical visits. She also underwent physical therapy. However, her left thigh muscle never returned to normal function and it began to atrophy—so much so that it appeared visibly smaller than her right thigh.
¶ 5 On May 10, 2006, an EMG and a nerve conduction study were performed on the patient by another doctor, Dr. Christopher M. Bouvette, a physician board-certified in Electrodiagnostic Medicine and Physical Medicine and Rehabilitation. Dr. Bouvette's report indicated that he had never seen this type of problem as a result of knee surgery. He recommended an MRI scan of the thigh and hip to make sure nothing was asserting pressure on the femoral nerve causing the damage.
¶ 6 The surgeon noted on June 7, 2006, that, according to the MRI, the femoral nerve appeared normal. Smith did not see the surgeon after August 16, 2006. Two months later, on December 14, 2006, the patient was examined by a third doctor, Dr. Charles J. Jablecki (neurologist), a board-certified neurologist. It was his opinion that the femoral neuropathy was most probably caused by a compression at the level of the groin during the surgical procedure. However, he also indicated that "further information would be needed beyond the information present in the medical records to answer the causation question with medical certainty."1
¶ 7 On July 9, 2007, Smith filed a lawsuit alleging that: 1) the surgeon was negligent-his treatment fell below applicable standards of care; 2) as a result of a breach of that care the patient suffered permanent injury; and 3) the surgeon's negligence could also be inferred through the application of res ipsa loquitur.2 On January 21, 2008, the surgeon filed a motion for summary judgment arguing that the patient failed to: 1) state a cause of action for negligence; 2) present the required expert testimony to support her cause of action; and 3) properly support her use of the res ipsa loquitur doctrine. The trial court granted summary judgment in favor of the surgeon on May 14, 2009, without explanation. The Court of Civil Appeals, in an unpublished opinion, affirmed the trial court. We granted certiorari on September 27, 2010.
¶ 8 THE TRIAL COURT ERRED IN GRANTING SUMMARY JUDGMENT.
¶ 9 The surgeon argues that the patient's medical negligence action must fail because she has not: 1) provided any qualified medical expert witness to testify that the surgeon's performance was below acceptable medical standards thereby causing the alleged injury; and 2) made any showing that any instrumentality solely within the surgeon's control caused or could have cause an injury to her thigh. The patient contends that at this stage of the proceeding, before discovery is conducted and further information becomes available, the report of the neurologist provides sufficient expert testimony to support her allegations.
¶ 10 At the outset we note that, prior to 2006, 63 O.S. Supp.2003 § 1-17083 required an affidavit be attached to the petition in order to file a medical negligence action attesting that a qualified expert had been consulted and issued an opinion sufficient to deem the claim meritorious. However, in Zeier v. Zimmer, 2006 OK 98, 152 P.3d 861, promulgated December 19, 2006, we held that this statute was unconstitutional because it: 1) was a special law prohibited by art. 5, § 464 of the Oklahoma Constitution; and 2) created an unconstitutional monetary barrier to the access to courts guaranteed by the Oklahoma Constitution art. 2, § 6.5
¶ 11 Here, the patient underwent surgery in January of 2006, but she did not file her lawsuit until July 9, 2007, after Zeier, supra, was decided. Two years later, the legislature repealed 63 O.S. Supp.2003 § 1-1708E and enacted 12 O.S. Supp.2009 § 196 which also attempts to require an affidavit in medical malpractice cases. Because no affidavit was required in the window in which the present cause arose, we need not address the Legislature's re-enactment of the affidavit requirement.
a. Professional Medical Negligence
¶ 12 Like all negligence claims, a prima facie case of medical negligence has three elements: 1) a duty owed by the defendant to protect the plaintiff from injury; 2) a failure to perform that duty; and 3) injuries to the plaintiff which are proximately caused by the defendant's failure to exercise the duty of care.7
¶ 13 Here, the dispute centers around the causation element. The cause of a plaintiff's injury is a question of fact for the jury to decide.8 Causation becomes a question of law only when there is no evidence and no reasonable inference from the evidence from which the jury could reasonably find a causal link between the negligent act and the injury.9 The question is whether a reasonable person could believe that the defendant's negligent conduct was a cause of the plaintiff's injury.10
¶ 14 In medical negligence cases, a physician's negligence is ordinarily established by expert medical testimony. However, when a physician's lack of care is so grossly apparent that laymen would have no difficulty recognizing it, expert testimony is not required to establish deficient care.11 Here, the patient provided the opinion of an expert witness, a board-certified neurologist, to support her allegations.12
¶ 15 The neurologist noted that prior to the surgery there was nothing wrong with the movement or nerves in the patient's thigh but after the surgery there was femoral nerve damage.13 He stated that it is "more probable than not" that the injury developed during the surgical procedure and except for the complication of the surgery she would not have developed a left femoral neuropathy.14 Nevertheless, he also noted that he would require additional information before the cause can be determined with certainty.15
¶ 16 In Robinson v. Oklahoma Nephrology Associates, Inc., 2007 OK 2, ¶ 11, 154 P.3d 1250, we explained that:
... Our case law requiring a medical malpractice plaintiff to produce evidence that injuries were caused by a particular physician's negligence has never required the production of experts who will utter a particular magic phrase, but focused instead on the particulars of each case. While the plaintiff must present evidence to remove the cause of her injuries from the realm of guesswork, she need not establish causation to a specifically high level of probability merely to withstand a demurrer to the evidence ...Absolute certainty is not required.16 (Citations omitted.) (emphasis supplied.)
¶ 17 This explanation regarding medical evidence is consistent with a long history of cases in which causation as presented by a medical professional was discussed. For example, in Cohenour v. Smart, 1951 OK 339, ¶ 7, 240 P.2d 91, the physician testifying for the plaintiff in a negligence action stated that the accident could have caused the injury, not "probably" caused the injury. The Cohenour Court, determining that corroborating evidence was lacking, noted:
... [I]t is incumbent upon the plaintiff, under the facts of this case, to prove not only that the accident could have caused the injury, but that it probably did ... [T]he authorities clearly hold that medical testimony as to the possibility of a causal relation between a given accident or injury and the subsequent impaired physical condition of the person injured is not sufficient, standing alone, to establish such a relation. `Testimony as to possibility' is said to mean testimony in which the witness asserts that the accident or injury `may have' or `could have' caused, or `possibly did' cause the subsequent physical condition, or that a given physical condition `might have,' `may have,' `could have,' or `possibly did' result from a previous accident or injury—testimony, that is, which is confined to words indicating the probability or likelihood of its existence.17
¶ 18 In Oklahoma Natural Gas Co. v. Kelly, 1944 OK 283, ¶ ¶ 8-10, 153 P.2d 1010, a case in which two chiropractors testified as expert witnesses as to the cause of an injury in an automobile accident, but two medical doctors testifed to the contrary, the Court said:
... While there is authority to the contrary, we are committed to the rule that opinion evidence, such as that given by the plaintiff's expert witnesses, that a certain cause `might', `could' or `possibly' did or would bring about a certain result is competent and may have some probative value... The value of such evidence is ordinarily for the trier of the facts. But where such evidence is not corroborated or supplemented by other evidence, and where the fact necessary to be established must be proved by testimony of a qualified expert, such evidence, standing alone, is generally held to be insufficient to make out a prima facie case....
On the question of whether the accident `could' cause the curvature of the spine, there was a disagreement between the chiropractors testifying for the plaintiff and the medical doctors testifying for the defendant, but it was for the jury to resolve the conflict and to give such weight to the testimony of each of the expert witnesses as it deemed proper....
We are of the opinion, and hold, that the evidence was sufficient to submit to the jury the question of whether the injuries complained of by the plaintiff, including the curvature of the spine, were caused by the accident. True, as above stated, the testimony of plaintiff's expert witnesses that said injuries `could' have been caused by the accident, standing alone, would not have been sufficient to submit to the jury the question of whether the curvature of the spine and the discomfort and injuries springing therefrom were caused by the accident, as the answer thereto would have been based upon conjecture and speculation, since it was shown that the curvature of the spine could have been brought about by several different causes. But proof of the cause and effect of the injuries in such a case need not rest entirely upon expert testimony. And when the expert testimony that the curvature of the spine `could' have been caused by the accident is considered along with the testimony that there was no curvature of the spine before, but was shortly after, the accident, and there is no factual evidence tending to prove any other cause, and the plaintiff's evidence reasonably tended to exclude every other possible cause, the jury could reasonably find that it was more probable that the curvature of plaintiff's spine and the ailments resulting therefrom were caused by the accident than by any other cause, and such a finding cannot be said to be based upon speculation and conjecture.18 (citations omitted.)
¶ 19 A motion for summary judgment should be sustained only when the pleadings, affidavits, depositions, admissions, or other evidentiary materials establish that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law.19 All conclusions drawn from the evidentiary material submitted to the trial court are viewed in the light most favorable to the party opposing the motion.20 Even when basic facts are undisputed, motions for summary judgment should be denied, if under the evidence, reasonable persons might reach different conclusions from the undisputed facts.21
¶ 20 The determination of causation may be removed from the province of the fact-finder only when there is a complete lack of evidence and no reasonable inference tending to link the defendant's negligence to the plaintiff's harm.22 Here, there is not an absence of proof that the surgeon's treatment proximately caused the patient's injuries. Rather, the neurologist's conclusions are probative and supported by corroborating evidence that nothing was wrong with her thigh before the surgery. After the surgery she suffered from nerve damage and atrophy and nothing else indicated that such nerve damage was caused by any other event. Consequently, the expert testimony may be used to support the claim of negligence under the teachings of our previous decisions. The patient has presented competent and sufficient evidence to make a prima facie case that she was injured during knee surgery and that the surgeon caused the injury. In other words, a reasonable person could conclude that an injury was sustained during the surgery and that surgeon was the cause of the injury. Accordingly, the trial court erred in granting the motion for summary judgment on the claim of negligence.
b. Res ipsa loquitur.
¶ 21 Res ipsa loquitur is statutorily codified in 76 O.S. 2001 § 21.23 The purpose of the res ipsa loquitur evidentiary rule is to aid the plaintiff in making out a prima facie case of negligence in circumstances when direct proof of why the harm happened is beyond the power or knowledge of the plaintiff.24 Under § 21, negligence is presumed to have occurred when the plaintiff establishes an injury which was proximately caused by an instrumentality solely within the control of the defendant and would not have occurred absent negligence on the part of the defendant.25
¶ 22 To establish a prima facie case for res ipsa application, the patient was required to show that: 1) an injury to the thigh muscle/nerves does not usually occur during the course of a knee surgery; 2) the surgeon had exclusive control and management of the instrumentality that caused the injury: 3) evidence shedding light on the harmful event is more accessible to the surgeon than the patient; and 4) the injurious event is the sort of occurrence which, in the ordinary course of events, would not have happened if one having control of the instrumentality exercised due care.26
¶ 23 While 76 O.S.2001 § 2127 may, at the discretion of the trial court, require expert testimony when it is determined that a degree of knowledge or skill not possessed by the average person is necessary, we recently noted that professional proof may be unnecessary under the theory of res ipsa loquitur. In Zeier v. Zimmer, 2006 OK 98, 152 P.3d 861, we addressed the constitutionality of a statutory requirement that an affidavit be attached to the petition in a medical negligence action. The Court, in striking the statute as unconstitutional, stated that the nature of a res ipsa loquitur claim may negate the necessity of expert testimony to prove the cause.28
¶ 24 It is obvious that the control of the evidence as to what actually happened in the surgery lies with the surgeon. A patient placed under anesthesia preparatory to surgery relinquishes to the attending physician, and to those who assist in the procedure all control over his/her body.29 There is no question that the surgeon is the person in charge of the procedure, the room, the patient, and those who assisted him. Nor is it disputed that an injury to the thigh muscle/nerves does not ordinarily occur during a knee surgery without something having gone wrong. In fact, the surgeon insists that it was not possible.
¶ 25 The record reflects that between the patient's account and the expert's evaluation, there is a disputed fact question as to what "instrumentality" could have caused the injury. According to the neurologist, it could have been: 1) a mistake in administering a nerve block and lateral release /or not administering such a block/release; or 2) a compression injury due to the restraints used to hold the knee in place or a tourniquet used during surgery; or 3) a combination of these.
¶ 26 The disputed evidentiary materials collectively show that: 1) with the exception of the knee condition, the patient was in general good health before the surgery; 2) the patient was sedated during the surgery; 3) the patient's left thigh was normal before going into the knee surgery; 4) the patient was informed that something went wrong during the surgery; 5) the thigh injury could have been cause by compression during the surgery or a nerve block or lack thereof; 6) an injury to the thigh does not normally result from a proper knee surgery; and 7) after the surgery the thigh muscle suffered limited motion and atrophy.
¶ 27 The evidentiary materials coupled with the expert testimony, presents questions of fact from which a reasonable persons might reach different conclusions. As we recently explained in Deweese v. Patterson UTI Drilling Co., 2010 OK 10, ¶ 19, 229 P.3d 540, quoting Harder v. F.C. Clinton, Inc., 1997 OK 137, 948 P.2d 298, and Qualls v. U.S. Elevator Corp., 1993 OK 135, 863 P.2d 457:
The effect of the res ipsa loquitur evidentiary rule is merely to raise a rebuttable inference which allows a plaintiff to take the case to the jury and thus avoid a directed verdict for the defendant. Where the proof is conflicting or subject to different inferences, some of which are in favor of and others against the applicability of res ipsa loquitur, the question must be left to the jury. (Citations omitted, emphasis in original.)
The trial court prematurely granted summary judgment on this issue as well.
CONCLUSION
¶ 28 A motion for summary judgment should be sustained only when the pleadings, affidavits, depositions, admissions, or other evidentiary materials establish that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law.30 All conclusions drawn from the evidentiary material submitted to the trial court are viewed in the light most favorable to the party opposing the motion.31 Even when basic facts are undisputed, motions for summary judgment should be denied, if under the evidence, reasonable persons might reach different conclusions from the undisputed facts.32 Summary judgment was premature because the patient presented sufficient evidentiary material to make a prima facie case that: 1) her knee surgery was caused by the surgeon's negligence; and 2) the res ipsa loquitur evidentiary rule may be applicable.
CERTIORARI PREVIOUSLY GRANTED; COURT OF CIVIL APPEALS OPINION VACATED; TRIAL COURT REVERSED AND REMANDED.
COLBERT, V.C.J., KAUGER, WATT, EDMONDSON, REIF, COMBS, GURICH, JJ. concur.
TAYLOR, C.J., WINCHESTER, J. dissent.
