Date: 07-15-2018

Case Style:

Case Number: D072015

Judge: Huffman, Acting P.J.

Court: California Court of Appeals Fourth Appellate District Division One on appeal from the Superior Court, San Diego County

Plaintiff's Attorney: David D. Miller and Patricia James

Defendant's Attorney: Clark R. Hudson, David P. Burke and Elizabeth A. Harris

Description: Plaintiffs and appellants Angela Belfiore-Braman and Stephen Braman
(sometimes together Plaintiff) appeal a defense judgment entered on a jury verdict, in
their medical malpractice action against defendant and respondent D. Daniel Rotenberg,
M.D. (Defendant), an orthopedic surgeon. The jury found Defendant was not negligent
in the care and treatment of Ms. Belfiore-Braman during the hip replacement surgery he
performed on her, and accordingly, it did not answer the special verdict's question on
whether such negligence was a substantial factor in causing injury to her, or loss of
consortium to her husband and fellow plaintiff.
The issues on appeal center around the trial court's ruling in limine, after a hearing
under Evidence Code1 section 402, that excluded certain medical opinion testimony
Plaintiff offered on issues of causation and damage, from her recently designated
nonretained expert witness Dr. Aaron G. Filler, M.D., Ph.D. ("Dr. Filler"). The court
determined that the proposed testimony would be unduly duplicative within the meaning
of section 723 (allowing the court to limit the number of expert witnesses to be called by
any party). Instead, the nonretained expert witness would be allowed to testify to the jury
only as to his observations from an imaging study he performed and what the test results
revealed to him about Plaintiff's condition.2
Plaintiff now argues this ruling in limine unfairly prevented her from making a
showing that Defendant's alleged negligent acts were a substantial factor in causing her
injuries. (Jennings v. Palomar Pomerado Health Systems, Inc. (2003) 114 Cal.App.4th

1 All further statutory references are to the Evidence Code unless noted.
2 A "nonretained expert" is an occupational expert, such as a treating physician,
police officer, or others who might testify as an expert but whose opinions are formed as
part of normal occupational duties. (Gonzales v. Windlan (Colo. App. 2014) 411 P.3d
878, 884.)
3
1108, 1118 (Jennings) [substantial factor test requires plaintiff to prove cause-in-fact].)
However, we conclude the record supports the ruling. Plaintiff cannot show the trial
court abused its discretion in precluding the offered testimony on causation and damage.
(Id. at p. 1119, fn. 9 [abuse of discretion standard applies to admissibility of an expert's
opinion on causation].) We affirm the judgment and its underlying ruling in limine.
I
BACKGROUND FACTS; DESIGNATION OF EXPERTS
Plaintiff was injured in an accident in 2006. In 2012, she consulted Defendant,
who diagnosed her with moderate to severe arthritis of the left hip. She initially received
nonsurgical treatments, and on April 23, 2013, he performed a left total hip replacement
surgery. After surgery, she complained of numbness in both legs, left greater than right.
Her left-sided symptoms persisted and Defendant concluded she had left-sided nerve
irritation (neuropraxia).
At Plaintiff's final visit with Defendant in March 2014, she reported some of her
symptoms had improved, but she was still experiencing lower limb weakness, pain, and
sensation abnormalities, including a drop foot condition. On July 18, 2014, her amended
4
complaint was filed against Defendant, as well as others who were dismissed prior to or
during trial.3
Defendant filed an answer and discovery began. For the expert witness exchange
in September 2015, Plaintiff designated as her expert Dr. Eric Meinberg, a board certified
orthopedic surgeon, for testimony on "all issues regarding standard of care, causation and
damages." She also identified a number of treating doctors and nonretained experts,
including her primary care provider Dr. Consuelo Ocampo. It is not disputed that
Defendant designated Dr. Craig Swenson, also a board-certified orthopedic surgeon, on
standard of care and related issues.
In the spring of 2016, Dr. Ocampo referred Plaintiff to Dr. Filler's office for an
MR neurography study. The results of this May 18, 2016 imaging study were sent to Dr.
Ocampo and Plaintiff in June 2016, and forwarded to her attorney. Consistent with his
imaging practice, Dr. Filler did not meet with or speak to Plaintiff during the study.
Plaintiff's "Amended" First Expert Exchange was served in July 2016, disclosing
that she had recently undergone the study with Dr. Filler.4 She also disclosed a new
treating doctor, Dr. Robert C. Pace, and added him and Dr. Filler to her list of "treating

3 The elements of Plaintiff's medical negligence cause of action allege "(1) the duty
of the professional to use such skill, prudence, and diligence as other members of his
profession commonly possess and exercise; (2) a breach of that duty; (3) a proximate
causal connection between the negligent conduct and the resulting injury; and (4) actual
loss or damage resulting from the professional's negligence." (Turpin v. Sortini (1982) 31
Cal.3d 220, 229-230.)
4 It does not appear that the motion procedure for augmenting a party's expert
witness list was utilized here. (Code Civ. Proc., § 2034.610.)
5
health care providers/non-retained experts to testify regarding the issues of standard of
care, treatment, diagnosis, prognosis, causation and why and how [she] was injured or
damaged as claimed." Dr. Meinberg was still the only designated Plaintiff's expert.
Defendant promptly took Dr. Filler's deposition. He understood he was not
designated as an expert in this case, and testified during the deposition that over his
career, he had seen about 20 patients who had a sciatic problem after hip surgery. Sciatic
nerve problems can stem either from trauma or a condition called piriformis syndrome, in
which the nerve running through the piriformis muscle can become torn, irritated, or
pinched.
From the nerve imaging study Dr. Filler performed for Plaintiff, he believed there
were several possible causes for the sciatic nerve entrapment he observed. He attributed
it to an improper placement of the retractor during the hip replacement surgery, leading to
direct injury to the nerve, or possibly other types of mechanical pulling, catching, or
burning that injured the sciatic nerve. Dr. Filler's neurosurgery practice does not include
performing total hip replacements. In conducting his study, he did not review
Defendant's medical records or the operative report from the surgery. He could not say
precisely what happened at the time that must have caused the neurologic symptoms.
II
TRIAL AND VERDICT
A. Introduction
After taking Dr. Filler's deposition, Defendant filed a motion in limine to preclude
him from testifying at trial, in part because he did not perform such surgery and had not
6
reviewed the operative notes. Defendant also argued his opinions only established
possibilities about the cause of injury, rather than probable causes. (Jones v. Ortho
Pharmaceutical Corp. (1985) 163 Cal.App.3d 396, 402 ["Mere possibility alone is
insufficient to establish a prima facie case."].)
Plaintiffs opposed the motion and submitted Dr. Filler's declaration in support of
the medical and legal validity of his imaging study, generally and as performed on
Plaintiff.5
When trial began in December 2016, the court heard and ruled on other motions in
limine, but deferred ruling on the motion to exclude Dr. Filler's expert testimony until a
section 402 evidentiary hearing was held. We examine the subsequent ruling for whether
the record indicates the court abused its discretion by preventing Plaintiff from fully and
fairly setting forth her evidentiary presentation on her theory of the case. (Monroy v. City
of Los Angeles (2008) 164 Cal.App.4th 248, 266-267 (Monroy); Tudor Ranches, Inc. v.
State Comp. Ins. Fund (1998) 65 Cal.App.4th 1422, 1432; §§ 723, 352.) The court's
evidentiary rulings must not "undercut a plaintiff's case by preventing that party from
presenting evidence in an organized and coherent way." (Monroy, supra, at pp. 267.)

5 Originally, Defendant's motion challenged whether MR neurography, the type of
imaging study invented, ordered and reviewed by Dr. Filler, is generally accepted as
reliable within the scientific community. (Sargon Enterprises, Inc. v. University of
Southern California (2012) 55 Cal.4th 747, 772, fn. 6 (Sargon Enterprises) ["general
acceptance" test for admissibility of expert testimony based on new scientific techniques
applies in California]; People v. Kelly (1976) 17 Cal.3d 24.) However, Defendant
conceded that point during the section 402 hearing, and no such issue is before us on
appeal. The record on appeal has been augmented to include Dr. Filler's declaration in
support of his methodology and his conclusions.
7
With these standards in mind, we generally outline the medical testimony
presented at trial, with attention to the elements specified in the special verdict form. The
jury was required to determine whether a breach of the professional's duty of care
occurred, before it reached the question of a causal connection between any negligent
conduct and the resulting injury. (Turpin v. Sortini, supra, 31 Cal.3d 220, 229-230.)
B. Plaintiff's Case
Plaintiff presented her own testimony about the surgery and her condition before
and afterwards. Her husband and coplaintiff likewise testified. She then offered
testimony from her designated orthopedic surgery expert, Dr. Meinberg, on the standard
of care, causation, and damages. He explained the surgery method used here was a
posterior approach to the hip, in which an incision was made and the muscles in the area,
including the piriformis, were parted before the replacement components could be
inserted. In his opinion, Defendant had failed to meet the applicable standard of care,
particularly because the surgery resulted in nerve damage and a length discrepancy in
Plaintiff's limbs. Possible difficulties at surgery included the question of whether the
replacement hip components were too tight, causing problems in placement (in getting
the hip reduced and impacting the sciatic nerve).6
With regard to the position of a patient's hip and knee during hip replacement
surgery, Dr. Meinberg testified it can affect the sciatic nerve, and the retractors used can

6 As used in surgery, the term "reduced" means "[t]o set (a broken bone); to restore
(esp. a dislocated, fractured, or herniated part) to a normal anatomical position." (OED
Online, Oxford University Press, www.oed.com/view/Entry/160503 "reduce, v.,"
June 25, 2018.)
8
stretch and bruise the nerve, resulting in sciatic nerve injury. Dr. Meinberg reviewed
Defendant's operative report and was unable to determine whether or how Plaintiff's
position during surgery had caused her problems, but said that generally, sciatic nerve
injury will occur when the nerve is either stretched or malpositioned too long. Dr.
Meinberg concluded from the evidence he reviewed that the nerve must have been
stretched too much, there was a clear cause and effect, the injury was not spontaneously
arising (idiopathic), and the surgery performance was a substantial factor in contributing
to the ultimate injury. He believed that Plaintiff's injury was a combination of the leg
length discrepancy (one centimeter) along with how other protocols were used during
surgery.
During cross-examination, Dr. Meinberg agreed that even if this type of surgery is
performed perfectly, with optimal positioning, risks can still include nerve damage and/or
limb length discrepancy. During surgery, an orthopedist ordinarily will not search for the
sciatic nerve, because such a search could cause injury to it. The orthopedic community
considers it acceptable if there is a postoperative limb length discrepancy of two
centimeters or less, such as Plaintiff has.
C. Ruling In Limine
After the two days of trial outlined above, the court returned to the section 402
hearing on the extent to which Dr. Filler could testify at trial. Defendant argued that the
offered opinions about possible causes of Plaintiff 's nerve injury were speculative,
irrelevant, and unduly prejudicial, and Dr. Filler had not been properly designated as an
expert.
9
In response, Plaintiff submitted Dr. Filler's declaration filed before trial, in support
of his scientific evidence as it would relate to Plaintiff. (See fn. 5, ante; the declaration
cites many other court cases in which this technology has been accepted.) With regard to
Plaintiff's individual case, Dr. Filler gave the opinion that the type of imaging he
performed could support reasonable circumstantial inferences about how she was
harmed. He detected that her sciatic nerve was severely injured in a location closely
adjacent to where Defendant was working. His deposition testimony had listed a series
of extraordinary mechanical events that could have caused such an injury, through the
actions of the surgeon. His declaration stated that causation could be shown by his
information as to proximity and type of injury, since only Defendant had been applying
force or controlling the actions of others, in the location where this occurred. Moreover,
Dr. Filler's observations showed that the tissues overlying the sciatic nerve showed no
evidence of trauma, except for the surgical incision. To a reasonable degree of medical
certainty, "more probable than not," his opinion was that Plaintiff's neurological deficit
was due to an injury to the sciatic nerve that was caused by Defendant during the surgery.
He believed that the type of injury he observed in Plaintiff's study was only compatible
with negligence.
The court then heard testimony from Dr. Filler, explaining he reviewed the
defense motion in limine and Plaintiff's opposition to it, in preparation for the section 402
hearing. He did not personally see Plaintiff as a patient when she came in for the MR
neurography testing, which is consistent with his custom and practice for imaging
patients. His study revealed her sciatic nerve was not severed, but it was compressed and
10
distorted. He formed the impression that during surgery, a significant and excessive
degree of mechanical force was applied to the nerve, sufficient to injure it severely. This
was "[m]ost likely, either a misplaced retractor or the hip joint element slipping and
crushing the nerve during the course of trying to assemble it." He believed that to a
reasonable degree of medical certainty, the nerve injury was causally connected to the
surgery.
Dr. Filler does not perform hip replacements as part of his practice. He could not
quantify the amount of force which would injure the sciatic nerve during surgery, except
to say it must have been more than the nerve could tolerate. Other than interpreting the
study and recommending a treatment plan, he did not perform any treatment for Plaintiff.
Even though Defendant was no longer contesting the reliability of Dr. Filler's
imaging technology, he continued to argue that the proposed testimony was inadmissible
because it would amount to duplicative expert opinion testimony. As Plaintiff's expert,
Dr. Meinberg had already testified on standard of care and causation, and Defendant
objected to Dr. Filler also testifying on causation or how he thought Defendant breached
the standard of care. Defense counsel further argued Dr. Filler was not a treating
physician, because Plaintiff could not show she met with him or that his study was ever
used in her treatment.
Plaintiff responded that Dr. Filler's analysis remained relevant on issues of
substantial factor causation, as well as treatment, so the jury should hear his testimony.
Having reviewed Dr. Filler's declaration and deposition, the trial court granted the
defense motion in limine in part, to disallow Dr. Filler from testifying to the jury about
11
anything beyond what he had learned from the diagnostic tool and its test results.
Plaintiff would therefore not be allowed to provide his testimony to show causation of
injury and damages, because Plaintiff had already designated an orthopedic surgeon as
her expert on those topics and duplicative testimony was inappropriate. (§ 723.)
Further, the court found that Dr. Filler did not qualify as a "treating" doctor, since
there was no showing his study had been used for her treatment. (See Schreiber v. Estate
of Kiser (1999) 22 Cal.4th 31, 36 (Schreiber) ["A treating physician is not consulted for
litigation purposes, but rather learns of the plaintiff's injuries and medical history because
of the underlying physician-patient relationship."])
However, the court permitted Dr. Filler to give testimony that described the
imaging study he performed and its results, including his observations that the sciatic
nerve was compressed or distorted. Dr. Filler told the jury that the study he performed
showed that her sciatic nerve was not severed, but it was "very distorted in shape just as it
went past the hip replacement location." On cross-examination, Dr. Filler testified the
study showed Plaintiff's sciatic nerve went through her piriformis muscle.
D. Defense Case; Verdict
At the next day of trial, Defendant testified on his own behalf. Before Plaintiff's
surgery, he had discussed with her the risks and benefits associated with the surgery,
including the potential risk of injury to the many nerves in the area and the risk of leg
length discrepancy. During the surgery, Defendant used a posterior approach and
standard techniques to minimize the risk of nerve compression or stress, such as
protecting the nerves and positioning the hip and patient in certain ways. He used
12
fluoroscopy to ensure the hip replacement components were in the correct position.
Several trial components were used before he placed the final hip replacement
components in the body. It was necessary to exert some physical force by pulling on the
leg "to make sure that the hip doesn't spontaneously dislocate because that's one of the
bigger complications that can go on." He found that one trial component was a little too
tight, and therefore used another, which he thought looked and worked great. He did not
identify any complications occurring during surgery.
Defendant took a postoperative full length x-ray, which showed that Plaintiff's
limb length discrepancy was less than one centimeter. Defendant believed that he met
the applicable standards of care during Plaintiff's surgery and her postoperative treatment.
In his opinion, nerve injury of this type can still occur even if the surgery is performed
perfectly, and Plaintiff's nerve injury was spontaneously arising or idiopathic in nature.
He did not know why her condition improved after surgery, but then stopped improving.
The defense orthopedic surgery expert, Dr. Swenson, reviewed the records and
concluded that Defendant had complied with the standards of care applicable to
performing surgery and rendering postoperative care. There were many mechanisms,
such as pulling too hard, that could cause a patient's sciatic nerve injury (palsy) during
such surgery. He could not be certain whether any of them contributed to Plaintiff's
injury, or whether it was a complication that could happen during any hip replacement
surgery. Even when an orthopedic surgeon is doing the best job possible, the sciatic
nerve can still be injured in several ways during surgery, somewhere between one to nine
13
percent of the time. Dr. Swenson did not see any indication that her positioning during
surgery was over-lengthened, so as to cause excessive tension on the sciatic nerve.
According to Dr. Swenson, an orthopedic surgeon has no way of knowing whether
a patient has a sciatic nerve running through the piriformis muscle, because the surgeon
does not go looking for the nerve during the surgery. Ninety percent of the time, the
sciatic nerve runs underneath the piriformis muscle, but in one or two percent of cases,
the nerve runs through the muscle. In some surgery cases using a posterior approach, the
piriformis muscle must be released before the surgeon can access the operative field. Dr.
Swenson testified that Plaintiff's limb length discrepancy, one centimeter, represents a
surgery result that is within the standard of care. There are a lot of variables to take into
consideration to match the two limbs. However, "leg length is not the absolute most
important thing. The absolute most important thing is to have a stable, well-positioned,
moving hip," and he did not know of any evidence that this was not the case here.
During closing argument, Plaintiff acknowledged there are many ways in which
such a surgery can result in nerve damage from traction and tension, and suggested to the
jury that her injuries were caused by Defendant's inattention to her situation. The jury
received appropriate instructions for determining whether Defendant had breached the
appropriate standard of care for an orthopedic surgeon. The jury was advised that
success is not required, and an orthopedic surgeon is negligent only if he or she was not
as skillful, knowledgeable or careful as a reasonable orthopedic surgeon would have
been, under similar circumstances.
14
After deliberating, the jury returned a verdict in favor of Defendant, by answering
"No" to the question of whether Defendant was negligent in the care and treatment of
Plaintiff. The jury accordingly did not respond to question 2, on substantial factor
causation. This appeal followed.
III
CAPACITY OF WITNESS: EXPERT OR TREATING PHYSICIAN
In response to Plaintiff's claims of error on appeal, Defendant takes the position
that it does not matter whether Dr. Filler was properly to be characterized as a treating
physician or a nonretained percipient expert, since it was appropriate for other reasons for
the trial court to limit his opinion testimony. Defendant contends Dr. Filler's testimony
on causation and damages factors would be duplicative of the opinions offered by the
other designated medical expert witness for Plaintiff. (See Scalere v. Stenson (1989) 211
Cal.App.3d 1446, 1454 (Scalere) [proper for court to restrict a second expert witness's
testimony to "any 'area that hasn't been gone into' "].) Moreover, he argues Plaintiff had
not shown that Dr. Filler had an adequate foundation for rendering such expert opinions
in this context of orthopedic surgery, which he did not practice. Defendant further claims
there could have been no prejudice, since the jury never reached the causation questions
in the given sequence of the special verdict.
For purposes of addressing Plaintiff's arguments about abuse of discretion in
excluding Dr. Filler's evidence, we accept the proposition that on this record, Dr. Filler
can fairly be considered to be a treating physician in some sense. Plaintiff's longtime
treating doctor, Dr. Ocampo, commissioned and received Dr. Filler's imaging report for
15
her. He recommended a treatment plan, although there was no showing it was ever
implemented. It is not disputed that Plaintiff promptly notified Defendant when she
consulted Dr. Filler, and Defendant immediately took his deposition, upon receiving her
amended designation of him as a nonretained expert. By filing the motion in limine,
Defendant effectively preserved all objections to the capacity of the witness and his
proposed substantial factor causation testimony.
At the section 402 hearing, Dr. Filler was cross-examined, saying that although he
was not a retained expert in this case, he read the defense motion in limine and Plaintiff's
response, and filed a declaration supporting the legal validity of his evidence as related to
Plaintiff. Defense counsel asked him whether he was indicating, from his perspective,
that there must have been a significant and excessive mechanical force that was applied
to Plaintiff's sciatic nerve during surgery. Dr. Filler responded that during his deposition,
he had been asked to come up with different scenarios under which the injury could have
occurred, and was able to conclude that some type of unacceptable level of mechanical
force was applied in order to cause what he saw in the study.
Traditional distinctions between a treating doctor and an expert medical witness
are not determinative of the issues Plaintiff raises on appeal. "A treating physician is a
percipient expert, but that does not mean that his testimony is limited only to personal
observations. Rather, like any other expert, he may provide both fact and opinion
testimony. As the legislative history clarifies, what distinguishes the treating physician
from a retained expert is not the content of the testimony, but the context in which he
became familiar with the plaintiff's injuries that were ultimately the subject of litigation,
16
and which form the factual basis for the medical opinion." (Schreiber, supra, 22 Cal.4th
31, 35-36.)
In some cases, it is possible for a treating physician to be transformed into a
retained expert, such as where counsel supplies the physician with "additional
information and ask[s] him to testify at trial to opinions formed on the basis of that
additional information." (Dozier v. Shapiro (2011) 199 Cal.App.4th 1509, 1521.) When
that occurs, the treating physician goes beyond the traditional role of examining a patient
by receiving additional materials from counsel after his deposition and using them to
form an opinion about another doctor's adherence to the standard of care, and the rules for
disclosing new information from a retained expert apply. (Ibid.; Schreiber, supra, 22
Cal.4th at p. 38; see Ochoa v. Dorado (2014) 228 Cal.App.4th 120, 141 [plaintiffs were
entitled to present testimony, outside of expert witness disclosure rules, from nonretained
treating physician on subject of reasonable value of medical services, "as long as such
testimony is based on facts acquired in the physician-patient relationship or otherwise
acquired independently of this litigation," but not acquired for the purpose of forming
and expressing an opinion in preparation for trial; italics added].)
Plaintiff cannot be heard to argue that Dr. Filler was merely a treating doctor who
should be exempt from expert disclosure requirements, since he would be testifying with
the background of having reviewed the motion in limine materials, such as an expert
would be required to do. We also find unpersuasive her claim that other doctors perform
this kind of imaging study, and Defendant possibly could have found another opposing
expert in a timely manner.
17
The relevant facts are that not only did Dr. Filler make personal observations in
his study, but he also reviewed material each counsel had prepared for trial. (Schreiber,
supra, 22 Cal.4th at p. 38.) The current problem is whether the trial court's ruling in
limine properly evaluated the proposed scope of Dr. Filler's testimony in light of the
relevant procedural circumstances, which include Plaintiff's previously disclosed
designation of another medical expert, an orthopedic surgeon, and Dr. Filler's review of
the defense motion in limine and opposition to it, in preparation for the section 402
hearing. (§ 723; Dozier v. Shapiro, supra, 199 Cal.App.4th 1509, 1521 [doctor reviewing
records as an expert is no longer merely a treating physician, and can be precluded from
testifying to opinions formed for purposes of litigation, without previous disclosures].)
IV
EXERCISE OF DISCRETION IN EXCLUDING TESTIMONY
A. Introduction
An abuse of discretion standard of review applies to this ruling placing limits on
Dr. Filler's testimony. (Sargon Enterprises, supra, 55 Cal.4th 747, 773.) "A ruling that
constitutes an abuse of discretion has been described as one that is 'so irrational or
arbitrary that no reasonable person could agree with it.' " (Ibid.) In exercising its
discretion, the trial court must act within the confines of the applicable legal principles
and consider whether the ruling "implicates a party's ability to present its case." (Ibid.)
During the section 402 hearing, Plaintiff mainly contended that Dr. Filler's
analysis would be relevant on issues of substantial factor causation, as well as treatment.
His opinions also appeared to extend to whether the professional standard of care was
18
met in this instance. The respondent's brief interprets Plaintiff's opening brief as focusing
only upon the exclusion of his opinions as to causation and damages. Defendant thus
claims any error in excluding such testimony would have been harmless, since the jury
did not reach the causation and damages questions, after deciding Defendant was not
negligent.
As previously outlined, the trial court essentially treated Dr. Filler as a nonretained
expert, or a specialist consultant who was assisting the treating doctors and evaluating the
surgery in hindsight. This was a reasonable approach under the circumstances, and based
on the manner in which Plaintiff has briefed the appeal, we decline to address whether
Dr. Filler's offer of proof could also be construed as addressing a broader range of issues,
such as breach of the standard of care. We address Plaintiff's claims only as to prejudice
on the causation and damages questions.
B. Foundational Questions
Plaintiff's designation of Dr. Filler as a nonretained expert implicated the trial
court's "gatekeeping" responsibility. (Sargon Enterprises, supra, 55 Cal.4th 747, 769.)
The court was required to assure that the foundational predicates for admission of any
expert testimony were met, such that it would assist the trier of fact in evaluating the
issues to be decided. (Id. at p. 770; § 802; Jennings, supra, 114 Cal.App.4th 1108, 1117;
Sargon Enterprises, supra, at pp. 771-772 [inquiry includes whether opinion is based on
unsupported reasons or is speculative].)
On causation, the plaintiff must establish "it is more probable than not the
negligent act was a cause-in-fact of the plaintiff's injury." (Jennings, supra, 114
19
Cal.App.4th 1108, 1118; italics omitted.) " 'A possible cause only becomes "probable"
when, in the absence of other reasonable causal explanations, it becomes more likely than
not that the injury was a result of its action.' " (Ibid., italics omitted.) "[C]ausation in
actions arising from medical negligence must be proven within a reasonable medical
probability based on competent expert testimony, i.e., something more than a '50-50
possibility.' " (Bromme v. Pavitt (1992) 5 Cal.App.4th 1487, 1504.) "[T]he evidence
must be sufficient to allow the jury to infer that in the absence of the defendant's
negligence, there was a reasonable medical probability the plaintiff would have obtained
a better result." (Alef v. Alta Bates Hospital (1992) 5 Cal.App.4th 208, 216.)
To assist in a causation determination, the expert must be able to explain why the
researched facts convincingly led to a conclusion that it is more probable than not that a
given negligent act was a cause-in-fact of the subject injury. (Jennings, supra, 114
Cal.App.4th at p. 1118; Cooper v. Takeda Pharmaceuticals America, Inc. (2015) 239
Cal.App.4th 555, 578 [insufficient basis if expert gives opinion about theoretical
possibilities or speculates about causation of injury].)
An initial problem with Dr. Filler's qualifications to express opinions about
causation is that he does not perform such hip replacement surgery. He has treated at
least 20 patients on neurological issues, after they received such surgery. In this case, he
did not review the operative report or Defendant's medical records, mainly reviewing the
study he ordered and in limine materials. Although he was allowed to testify that he
could see damage had occurred to the sciatic nerve, the court appropriately found he
lacked a foundation to discuss how the damage was caused. He could not quantify the
20
amount of force that would injure the sciatic nerve during surgery, but said it must have
been more than the nerve could tolerate. He could only speculate that "most likely" it
was a misplaced retractor or slippage of the hip joint element that damaged the nerve.
His declaration gave the opinion that it was "more probable than not" that the surgery had
caused the nerve injury.
Although Plaintiff complains that in making its ruling, the trial court did not
specifically address substantial factor issues, the context of the ruling makes it clear that
the court had all the appropriate considerations before it. Using either formulation of Dr.
Filler's opinions, the trial court had a reasonable basis to conclude that his views on
causation were too speculative to present to the jury. Based on the limited nature and late
timing of the work he performed for Plaintiff, the court had reason to determine that the
jury would not have been materially assisted by these opinions when deciding the issues
submitted to it. No abuse of discretion is apparent in its conclusions.
C. Cumulative Nature of Testimony
When Dr. Meinberg testified as Plaintiff's designated expert, he explained the
operative report did not clearly indicate whether or how Plaintiff's position during
surgery had caused her problems. He found the injury was not spontaneously arising, and
the manner of performance of surgery was a substantial factor in contributing to the
ultimate injury. Specifically, "judging by the difficulty in relocating the hip, we know
that the nerve was stretched too much," contributing to sciatic nerve injury. Generally,
however, sciatic nerve injury will occur when the nerve is either stretched or
inappropriately positioned for too long a period. He believed that Plaintiff's injury was a
21
combination of the leg length discrepancy along with how other protocols were used
during surgery.
Dr. Swenson testified as a defense expert that there were many mechanisms, such
as pulling too hard, that could cause a patient's sciatic nerve injury during such surgery.
He could not be certain whether any of them had contributed to Plaintiff's injury, or
whether it was a complication that could happen during any hip replacement surgery.
When Defendant testified, he explained that it was necessary to use some force to install
and test the trial implants, and that when he settled on one of appropriate size, it was
working great.
On appeal, Plaintiff argues that the testimony she provided from Dr. Meinberg did
not adequately address all essential issues concerning substantial factor causation of
injury, because his main focus was upon the limb length discrepancy resulting from the
surgery. She states, "[W]hereas Dr. Meinberg, an orthopedic surgeon, testified that the
standard of care was violated due to the length problem with [her] leg and this caused her
injury, Dr. Filler, a neurosurgeon, was going to testify that the excessive force used was
the cause of [Plaintiff's] injured sciatic nerve. Thus, there would have been different
testimony by two different types of doctors regarding causation and both were a
substantial factor in causing [her] injuries." She accordingly claims Dr. Filler's testimony
would not have been duplicative, and would have addressed the substantial factor issue as
reflected in the instruction given the jury. (CACI No. 430.)
There are several problems with this argument. First, Dr. Filler would have had to
address different manners of violation of the applicable standard of care, an issue which
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we have said has not been brought before us in this appeal. Next, Dr. Meinberg was
Plaintiff's designated expert for testimony on standard of care, causation and damages,
and he discussed whether the nerve had been stretched too much, such as through the
positioning during surgery or the use of retractors. That testimony was roughly
equivalent to considerations about an excessive use of force, such as Dr. Filler was
suggesting. Dr. Meinberg also stated that the length discrepancy alone was not a
problem, and that there were protocols used during the surgery that in his opinion, did not
meet the standard of care.
Under these circumstances, Dr. Filler's opinions about an excessive use of force
would have been cumulative and would not have addressed an " 'area that hasn't been
gone into.' " (Scalere, supra, 211 Cal.App.3d 1446, 1454.) The jury understood that
some force had to be used during the hip replacement surgery, within the appropriate
standard of care for this type of professional. There was defense testimony that
Defendant took appropriate steps to minimize compression and stress on the nerves, and
that this type of injury can occur even when standards of care are met.
The trial court had the discretion to make determinations on whether the opinion
testimony regarding causation that Plaintiff offered from Dr. Filler was unduly
cumulative, in view of the previous expert designations made. (§§ 723, 352.) Plaintiff
cannot show she was unfairly deprived of the opportunity to present evidence on the
relevant elements of her negligence case, or that a different result was probable if the
disputed evidence had been admitted. (Sargon Enterprises, supra, 55 Cal.4th at p. 773;
P&D Consultants, Inc. v. City of Carlsbad (2010) 190 Cal.App.4th 1332, 1348.)

Outcome: The judgment is affirmed. Costs on appeal to Respondent.

Plaintiff's Experts:

Defendant's Experts:

Comments: