News: The California 4th District Court of Appeal, Division One upheld a trial court’s summary judgment ruling in a medical malpractice lawsuit in favor of a dental hygienist who allegedly caused nerve damage to a patient.

The incident occurred during a routine dental appointment, during which patient received three injections of local anesthetic. According to the complaint, the first two injections did not cause any problems; however, the third injection caused severe pain followed by several symptoms, including swelling and difficulty maintaining control over the side of her face in which she received the third shot. The court held that, despite the plaintiff relying on res ipsa loquitur, an expert witness was needed to support her position regarding the breach in the standard of care. Because the plaintiff did not offer any expert opinion, but rather relied on her own declaration, the court affirmed the judgment in favor of defendant.

Background: The patient visited her regular dental clinic for a routine dental appointment. Because her regular dentist was running late, she was seen by another dentist at the office who recommended a deep cleaning procedure. The patient agreed and proceeded with the defendant, a registered dental hygienist who worked at the clinic.

The hygienist administered three injections of local anesthetic before performing the cleaning procedure. While the first two shots were described by the patient as “uneventful,” the patient immediately noticed something was wrong when the third shot was administered. In fact, the patient described feeling a “pop” in her mouth, which was followed by severe pain. Although the patient allowed the hygienist to finish the cleaning, she lamented various symptoms, including pain, swelling of her face and head, ear ringing, dripping from her left nostril, tearing from her left eye, and difficulty controlling the facial muscles in her left side.

After the incident, the patient filed a complaint for medical malpractice and general negligence against the dental clinic, the dentists, and the dental hygienist who performed the cleaning. The plaintiff alleged the hygienist negligently administered the third injection, causing damage to her trigeminal nerve. Defendant moved for summary judgment, which was granted, and provided declarations from two doctors who stated the hygienist performed according to the requisite standard of care.

In granting the summary judgment, the trial court noted the plaintiff made the mistake of not providing a competing expert opinion, which had been fatal to her action. On appeal, plaintiff argued that relying on the doctrine of res ipsa loquitur (“the thing speaks for itself”) had freed her from the burden of providing expert testimony regarding the standard of care. Defendants argued that by introducing expert declarations, the burden of proof to show the defendants’ conduct had breached the standard of care had now shifted to plaintiff, who would have had to provide an expert declaration to survive the summary judgment motion.

The court of appeal analyzed defendants’ proffered expert declarations, reviews of the patient’s treatment records, X-rays, charts, and the declarations of each party. While the court concurred with plaintiff in stating that expert declarations are only as good as the rationale on which the opinions they contain are based, the court found that defendants’ experts had provided sufficient background information to provide a valid opinion. Thus, the court found in defendants’ favor and upheld the trial court’s summary judgment decision.

What this means to you: The appellate court’s analysis in this case highlights how the application of res ipsa loquitur to medical malpractice cases still requires expert opinion. In fact, plaintiff was under the mistaken impression that because she relied on the doctrine of res ipsa loquitur — a legal theory under which “the thing speaks for itself,” meaning that an inference of negligence is supported when an injury would not have occurred if not for negligence on behalf of the person who controlled the object causing the injury — she would not need to present a declaration from an expert in support of her position.

The plaintiff argued the declarations presented by defendants’ experts were irrelevant because they did not address her theory causation; therefore, there was no need for her to provide her own declaration. However, the court found plaintiff’s position to be “misguided.” Specifically, the court noted expert opinions need not rule out certain injuries to find that no negligence occurred. On the contrary, if no negligence emerges from the patient’s records, experts can argue no negligence occurred, regardless of the injuries the plaintiff alleges. The court further stated that to require otherwise would equate to requiring experts to “prove a negative.” In other words, the fact the patient had suffered nerve damage and was presenting her case under a theory of res ipsa loquitur did not prevent the defendants’ experts from arguing that no negligence occurred just because the plaintiff suffered injuries.

In addition, the court stated that to support a motion for summary judgment, an expert’s declaration need not negate every element of a claim. In this case, the experts’ declarations analyzed the patient’s records and focused on the standard of care, only briefly touching on causation. The court opined the declarations provided a sufficiently supported conclusion the defendants had not acted negligently, at which point the burden of proving negligence occurred shifted to the plaintiff. Thus, plaintiff’s position that the doctrine of res ipsa loquitur excused her from any need to present expert medical testimony was inaccurate.

Primarily, the plaintiff relied on one precedent case involving a patient suffering an injury after receiving a number of cortisone injections. In said case, the court applied res ipsa loquitur to imply negligence had occurred, even though the patient’s records did not show anything out of the ordinary. Based on this, plaintiff argued that in cases involving injuries caused by injections, res ipsa loquitur could provide a theory of liability. However, the court noted res ipsa loquitur still required plaintiff to provide an expert’s declaration as to the fact that her injuries would not have occurred if it were not for negligence by someone in the defendant’s position. Thus, by failing to present any expert declaration, the plaintiff opened the door to the court’s granting of defendant’s summary judgment motion.

Regardless of what theory of liability the plaintiffs used, this case further demonstrates how the outcome of a medical malpractice case often lies in the strength of an expert’s testimony. At the very least, any plaintiff pursuing a medical malpractice claim should be prepared to proffer an expert’s declaration to support his or her position at summary judgment (and present testimony from that expert at trial) because doing otherwise could be fatal for the case.

Finally, it is doubtful anyone could guarantee a patient that receiving an injection will be painless and risk-free. It is possible that, for most injections into muscle, the clinician can assure the needle is not entering a blood vessel. But that is about the limit of control available. Hitting a nerve with the needle is painful at best and possibly a long-term problem at worst. It can happen even to the most experienced healthcare professional and to the most vulnerable patient. Nerves cannot be visualized under the skin or within the gums. There is a general location for larger nerves as they branch off the spinal cord, but once their fibers branch further away from their source, they become invisible to the naked eye. No two individuals will have the same nerves located in the exact same location due to the variability of the body from person to person. What is helpful to healthcare providers is to inform patients of the risks and side effects of anesthetic injections and document in the patient’s medical records the patient’s understanding and agreement or consent to receive the injection.


  • Decided Feb. 18, 2021, Case number D076991, in the California Fourth District Court of Appeal, Division One.