AFFIRM; and Opinion Filed August 30, 2019.




                                              In The
                                Court of Appeals
                         Fifth District of Texas at Dallas
                                      No. 05-17-01403-CV

                                 EDWINA OLIVER, Appellant
                                           V.
                                 PAUL SAADI, M.D., Appellee

                      On Appeal from the 162nd Judicial District Court
                                   Dallas County, Texas
                           Trial Court Cause No. DC-15-07763

                             MEMORANDUM OPINION
                         Before Justices Schenck, Osborne, and Reichek
                                  Opinion by Justice Schenck
       Appellant Edwina Oliver appeals a no-evidence summary judgment in favor of appellee

Paul Saadi, M.D. The trial court entered summary judgment after striking Oliver’s expert

witness’s report. In a single issue, Oliver contends the trial court erred in finding her expert’s

report unreliable.   Dr. Saadi contends Oliver waived error by not challenging all possible

justifications for the trial court’s ruling. For the reasons stated below, we affirm the summary

judgment. Because the dispositive issues in this case are settled in law, we issue this memorandum

opinion. See TEX. R. APP. P. 47.4.

                                              BACKGROUND

       Oliver was treated by Dr. Saadi for a spinal condition. Prior to undergoing surgery, Oliver

suffered from a host of conditions, including severe back pain, radicular leg pain on her right leg,
cervical myelopathy, and Parkinson’s disease. Her expert described her pre-operative spinal

condition as severe stenosis1 of the spinal canal at L3-4 and L4-5 along with bilateral foraminal

stenosis at L3-4 and on the right side of L4-5. In July of 2013, Dr. Saadi operated on Oliver, fusing

disks in her back. After the surgery, Oliver experienced foot drop.2 Her foot strength and mobility

measured at zero out of a range of five. However, by December of 2013 Oliver’s condition had

improved, and she could lift her foot with a strength measured at four out of five.3

             On July 10, 2015, Oliver filed suit for negligence against Dr. Saadi. In her petition, she

contended Dr. Saadi violated the standard of care for a reasonably prudent surgeon, proximately

causing her foot drop. Oliver designated Brent Morgan, M.D. as an expert witness on the standard

of care and causation and he prepared a report. Dr. Morgan is a board-certified neurological

surgeon who is currently the Neurotrauma Director at the Medical Center of Plano.4 In preparing

his expert report, he reviewed the following documents related to Oliver’s care: “medical records

from Doctors Hospital, medical records from Dr. Saadi, MRI report from Doctors Hospital at

White Rock Lake, an MRI scan report from Baylor Diagnostic Imaging Center, a medical record

of Dr. Sharisse Stephenson, a medical record of Dr. Vaughan.” In his report, Dr. Morgan

concludes there were several deviations from the standard of care. He states it is probable that

“had it [the foraminal stenosis] been addressed there would not have been a permanent

neurological injury.” However, the report does not specify what Dr. Morgan believed was the

cause of the foot drop.




      1
        Spinal stenosis is the narrowing of the spaces within one’s spine, which can put pressure on the nerves that travel through the spine. See
https://www.mayoclinic.org/diseases-conditions/spinal-stenosis/symptoms-causes/syc-20352961.
     2
       Foot drop is a general term for difficulty lifting the front part of the foot. See https://www.mayoclinic.org/diseases-conditions/foot-
drop/symptoms-causes/syc-20372628.
     3
       Morgan concedes that the “4/5” is a subjective measurement that differs in meaning between physicians, although he asserts there are certain
concrete distinctions between the numeric measurements.
     4
         Because Dr. Morgan’s qualifications are not at issue in this case, we need not address them further.

                                                                        –2–
       On November 24, 2015, Dr. Saadi filed an objection to Dr. Morgan’s report and

simultaneously filed a motion to dismiss. The trial court issued an order denying the motion to

dismiss and overruling Dr. Saadi’s objection.

       Thereafter, Saadi deposed Dr. Morgan. At the deposition, Dr. Morgan initially testified

that he did not know what caused the paralysis. Dr. Morgan also stated during his deposition that

foot drop is a known complication of some back surgeries, foot drop following surgery can occur

through non-negligent causes, and that the development of foot drop following surgery does not

mean “in and of itself” that the surgeon was negligent.

       Dr. Morgan was then asked what could have caused the foot drop. He listed several

possible causes including transection of the nerve root, severe traction injury, failure to decompress

an already compressed nerve, trauma to the nerve with placement of the fusion graft, potential

vascular injury, and postoperative hematoma causing compression. At this point in the deposition,

Dr. Morgan was unable to say which of the listed possibilities, in reasonable medical probability,

caused the foot drop. Dr. Morgan also stated that because he did not know the source of the foot

drop, he was unable to say whether earlier treatment would have reversed Oliver’s condition. More

particularly, Dr. Morgan testified:

       I would say that since nothing was done, I don’t know, but there is a possibility
       there could have been something there that was reversible at the time. I don’t know
       because [an MRI or CT] wasn’t done. I can’t opine about something that was not
       done.

       Later in his deposition, Dr. Morgan was informed of an MRI performed in March of 2014,

eight months after Oliver’s surgery. He claimed he did not know about this MRI. The March

2014 MRI showed a fluid collection that resulted in “moderate to severe descending nerve root

compression, most pronounced at the lower L4 level.” Upon learning of the March 2014 MRI,

Dr. Morgan revised his opinion and stated that a post-operative hematoma was the probable cause

of the paralysis. At this time, he stated that compression of the nerve resulted in a hematoma that
                                                 –3–
caused the foot drop. Dr. Morgan acknowledged that no post-operative study of the area was

performed prior to March 2014, so he could not know that there was a fluid collection present

immediately post-surgery. Moreover, he admitted that he could not say what a post-operative MRI

would have shown.

           Despite not knowing what an MRI right after surgery would have shown, Dr. Morgan

testified that in light of the 2014 MRI, it was more likely than not that a hematoma compressed

the nerve in Oliver’s foot, causing the foot drop. He stated that this was true even though Oliver’s

foot drop had improved significantly by December 2013.5 He further insisted that “things could

have been done differently” by Dr. Saadi.

           Soon thereafter, Dr. Saadi filed a motion to exclude Dr. Morgan’s testimony. The motion

challenged the reliability of Dr. Morgan’s opinions, arguing Oliver did not meet her burden of

establishing that Dr. Morgan’s opinions are reliable, especially with regard to causation. A few

weeks later, Dr. Saadi filed a no-evidence motion for summary judgment, in which he argued that

if the motion to exclude Dr. Morgan is granted, Oliver would be without expert testimony to

support her claims regarding the standard of care, the breach of the standard of care, and causation.

Expert testimony is typically required in medical malpractice cases in Texas to develop those

issues. See Rich v. Mulupuri, 205 S.W.3d 1, 2 (Tex. App.—Dallas 2006, pet denied).

           The trial court held a hearing on Dr. Saadi’s motion to exclude Dr. Morgan to determine

whether the expert evidence would become part of the summary judgment record. At the hearing,

counsel presented arguments and Dr. Morgan testified. Specifically, Dr. Morgan testified that

multiple things could have caused the foot drop, he did not know what caused the foot drop in this


     5
       Before the trial court the parties presented evidence that Oliver’s foot drop improved significantly between the surgery and December 2013,
even though the March 2014 MRI showed the fluid was still compressing the nerve months later and the radiology studies show the fluid collection
grew over the next year. Oliver pointed out this inconsistency to the trial court. At oral argument before this Court, Oliver argued the evidence in
support of this that was before the trial court was incorrect. Specifically, she stated that evidence presented was looking an incorrect section of the
MRI and that the inconsistency identified at the trial level was not actually an inconsistency. Whether or not that is true, our obligation is to review
the evidence that was properly before the trial court. The evidence properly before the trial court showed that the foot drop improved in the same
time frame that the fluid collection supposedly causing it grew in size.

                                                                         –4–
case, and that some of the possible causes of the foot drop would not have been negligence on the

part of Dr. Saadi.

       Dr. Morgan also testified that the purpose of a post-operative radiology study would have

been “to see if there was something that could have been corrected.” Again, Dr. Morgan did not

provide any evidence to support his assumption that a fluid collection existed around the time of

the surgery; only that one existed eight months later.     At the hearing, the following exchange

occurred between Dr. Saadi’s attorney and Dr. Morgan.

       Q: Dr. Morgan, from the day of surgery in July of 2013 until the MRI in March of
       2014, you don’t know along that spectrum because a film wasn’t done, when that
       fluid collection would have been at it[]s maximum, true?

       A: Correct. Can I correct that? I mean, I can extrapolate but I can’t point to
       something that says that. I can make an assessment of that, but I can’t tell you for
       sure but I can tell you what my feeling is. And I think I answered with Mr.
       Goetzmann’s question.

       Q: Dr. Morgan, you can’t say because those film studies weren’t done, you don’t
       know if it got bigger or got smaller, you don’t know, true?

       A: Well, once again, I think this is a -- where you and I kind of -- I misunderstand
       your questions. It’s not that I don’t know. I’m highly suspicious. But I can’t -- if
       you’re going to say well show me that that’s true. I can tell you that in my opinion,
       in my medical experience, it’s very likely that it was at its biggest immediately
       when the neurological deficit occurred and smaller later. That’s my opinion. That
       would be my -- you know, that would make sense, and I think that’s the right
       extrapolation.

       Dr. Morgan’s statements that he could “extrapolate,” he “didn’t know for sure,” “I can tell

you what my feeling is,” and “I think that’s the right extrapolation” are reflective of his responses

throughout the hearing. Aside from the fact that an MRI showed the existence of the fluid pool

eight months after surgery, the evidence before the trial court did not include further analysis or

reasoning supporting the proposition that the fluid was present immediately after Oliver’s surgery

or in the months in between.

       At the conclusion of the hearing, the trial court requested supplemental briefing on two

issues. First, whether Dr. Morgan was required as a matter of law to rule out all other possible
                                            –5–
causes of the foot drop. Second, whether Dr. Morgan’s testimony was sufficient on the issue of

whether “fluid was present at the time of surgery.” The parties submitted supplemental briefing

on both issues.

       Upon review, the trial court granted both the motion to exclude Dr. Morgan and the no-

evidence motion for summary judgment. Each order stated that the related motion was granted in

its entirety. The court did not specify its reasons for excluding the report; neither order explained

the court’s rationale. Oliver moved for a new trial, which was denied by operation of law. He

then timely filed this appeal. We must now determine whether the trial court abused its discretion

in finding Morgan’s testimony unreliable.

                                        WAIVER UNDER ST. JOHN

       As an initial matter, we pause to address a creative argument brought forward by Dr. Saadi;

namely, that we must not review the merits of this appeal because Oliver has not adequately briefed

her challenge to the admissibility decision under our decision in St. John Missionary Baptist

Church v. Flakes, 547 S.W.3d 311 (Tex. App.—Dallas 2018, pet. pending) (en banc).

Specifically, Dr. Saadi argues that Oliver waived error by not challenging what Dr. Saadi avers

are unchallenged “grounds” that could have served as the basis for the trial court’s admissibility

ruling, including several attacks on Dr. Morgan’s methodology, the foundational data underlying

his opinions, and the analytical gaps within his opinions, among others not specifically parried in

Oliver’s brief.

       In St. John we reaffirmed our application of the briefing waiver implications of Malooly

Brothers, Inc. v. Napier, 461 S.W.2d 119 (Tex. 1970) beyond summary judgments. St. John, 547

S.W.3d at 315. While parties are no longer required to “assign” or identify points of error, they

are required to bring forward “issues” sufficient to permit an appellate court to reverse the

underlying judgment. Id. The “issues” an appellant is obliged to raise under St. John and its

                                                –6–
antecedents are, again, a product of the presence of multiple independent bases available for the

underlying judgment, the lack of any explicit choice among them by the trial court, and the harmful

error rule. Id. “If an independent ground fully supports the complained of ruling or judgment, but

the appellant assigns no error to that independent ground, we must accept the validity of that

unchallenged independent ground, and thus any error in the grounds challenged on appeal is

harmless because the unchallenged independent ground fully supports the complained of ruling or

judgment.” Id. (quoting Oliphant Fin. LLC v. Angiano, 295 S.W.3d 422, 424 (Tex. App.—Dallas

2009, no pet.)).

        The word “grounds” still has a specific meaning in summary judgment practice. See TEX.

R. CIV. P. 166a(c). An admissibility determination, standing on its own, does not compel a

summary judgment. As the “issue” in this case is the propriety vel non of the court’s decision to

render summary judgment, Oliver is obliged to attack every ground that by and of its own force

could have produced the judgment. He is not obliged to marshal and attack every subsidiary

argument and citation to authority that may have informed the trial court’s thinking along the way.

To be sure, the arguments relating to the admission or exclusion of evidence may vary and here

include qualifications, reliability, and relevance. But none of these interstitial evidentiary debates

would amount either to a “ground” for summary judgment on their own account. And none of the

“justifications” appellee points out in her brief are “independent grounds” on which the trial court

could have granted summary judgment. Accordingly, we move forward to decide this appeal on

its merits.


                                          STANDARD OF REVIEW

        We review a trial court’s decision to exclude expert-witness testimony for an abuse of

discretion. Gharda USA, Inc. v. Control Sols., Inc., 464 S.W.3d 338, 347 (Tex. 2015). A trial

court abuses its discretion when its ruling is arbitrary, unreasonable, or without reference to any
                                                 –7–
guiding rules or legal principles. E.I du Pont de Nemours & Co. v. Robinson, 923 S.W.2d 549,

558 (Tex. 1995).

        For an expert’s opinion to be admissible under Texas Rule of Evidence 702, the expert

must be qualified, and the expert’s opinion must be relevant to the issues in the case and based

upon a reliable foundation. TEX. R. EVID. 702; Exxon Pipeline Co. v. Zwahr, 88 S.W.3d 623, 629

(Tex. 2002); Gammill v. Jack Williams Chevrolet, Inc. 972 S.W.2d 713, 720 (Tex. 1998);

Robinson, 923 S.W.2d at 556 (Tex. 1995). The relevance requirement, which incorporates

traditional relevancy analysis under Texas Rules of Evidence 401 and 402, is met if the expert

testimony is “sufficiently tied to the facts of the case that it will aid the jury in resolving a factual

dispute.” Robinson, 923 S.W.2d at 556 (quoting United States v. Downing, 753 F.2d 1224, 1242

(3rd Cir. 1985)).

        Rule 702’s reliability requirement focuses on principles, research, and methodology

underlying an expert’s conclusions. Id. at 557. Under this requirement, expert testimony is

unreliable if it is not grounded “in the methods and procedures of science” and is no more than a

“subjective belief or unsupported speculation.” Id. (quoting Daubert v. Merrell Dow Pharm.,

Inc., 509 U.S. 579, 590 (1993)). Reliable expert testimony must be based on a probability standard,

rather than on mere possibility. Gharda USA, Inc. v. Control Sols., Inc., 464 S.W.3d 338, 349

(Tex. 2015)

        Expert testimony is also unreliable if there is too great an analytical gap between the data

the expert relies upon and the opinion offered. Gammill, 972 S.W.2d at 727. In applying this

reliability standard, the trial court does not decide whether the expert’s conclusions are correct;

instead, the trial court determines whether the analysis used to reach those conclusions is

reliable. Id. at 728.




                                                  –8–
           When an expert is challenged, the proponent of the expert opinion must prove the reliability

of each opinion. Mack Trucks, Inc. v. Tamez, 206 S.W.3d 572, 578 (Tex. 2006). The proponent

bears this burden “regardless of the quality or quantity of the opposing party’s evidence on the

issue and regardless of whether the opposing party attempts to conclusively prove the expert

testimony is wrong.” Whirlpool v. Camacho, 298 S.W.3d 631, 639 (Tex. 2009). This burden

includes ensuring that the expert’s testimony contains no internal inconsistencies. See Gen.

Motors Corp. v. Iracheta, 161 S.W.2d 462, 470–72 (Tex. 2005).

           The trial court serves as a gatekeeper to screen out irrelevant and unreliable expert

evidence. Zwahr, 88 S.W.3d at 629. The trial court has broad discretion to determine the

admissibility of evidence, and we review the trial court’s decision under an abuse of discretion

standard. Id. A trial court abuses its discretion when it acts without regard to any guiding rules or

principles. Downer v. Aquamarine Operators, Inc., 701 S.W.2d 238, 241–42 (Tex. 1985).

Whether a trial court abused its discretion in making an evidentiary ruling is a question of

law. State v. Bristol Hotel Asset Co., 65 S.W.3d 638, 647 (Tex. 2001).

                                                    OLIVER’S ARGUMENT ON APPEAL

           On appeal, Oliver raises two primary arguments. First, Oliver employs a beekeeper

analogy found in Gammill to argue that Dr. Morgan has many firsthand observations of patients

suffering from post-neurological sequelae,6 making his experience sufficient as long as there is no

gap in his opinion rendering it unreliable.                             See Gammill, 972 S.W.2d at 724 (distinguishing

scientific and non-scientific expert testimony by explaining that if one wants to know how a

bumblebee flies, an aeronautical engineer might be a helpful witness. But, if one wanted to prove

bumblebees always take off into the wind, a beekeeper with no scientific training would be an

acceptable witness if a proper foundation were laid for his conclusions). We conclude the


   6
       Neurological sequelae are complications involving damage to the central nervous system that result in cognitive, sensory, or motor deficits.

                                                                      –9–
testimony in this case is not sufficiently analogous to Gammill and that the trial court would not

have abused its discretion in finding there is indeed an analytical gap rendering Dr. Morgan’s

testimony unreliable.

       In this case, the observations Dr. Morgan made in his career led him to the conclusion that

the foot drop might have resulted from up to six different causes. He also conceded that foot drop

was also a known complication of the surgery that could occur without negligence on the part of

the surgeon. Upon observing the March 2014 MRI, he elevated one of the six “possible” causes

to “probable.” We find Dr. Morgan’s analysis contained a material analytical gap such that the

trial court would not have been abusing its discretion in determining the analysis was unreliable.

The March 2014 MRI was performed eight months after the surgery took place. No MRI was

performed on the area immediately after the surgery. Although the evidence before the trial court

showed there was a fluid collection present in March 2014, no evidence showed the presence of a

fluid collection immediately following the operation. Moreover, Dr. Morgan admitted that he

could not say what an MRI taken post-surgery would have shown and he was unable to say that a

fluid collection existed at that time. Additionally, the evidence before the trial court showed

Oliver’s foot drop improved significantly between the surgery and December 2013, even though

the March 2014 MRI showed the fluid was still compressing the nerve months later and the

radiology studies show the fluid collection grew over the next year.

       Dr. Morgan was not able to explain how, if the fluid pool was the cause of the foot drop,

the foot drop could improve while the fluid pool causing it increased in size. Oliver’s burden of

proving reliability included showing his expert’s opinion did not contain internal inconsistencies

such as this one. See Gen. Motors Corp. 161 S.W.2d at 470–72. Lastly, Oliver’s reliance on

Gammill improperly attempts to equate an expert’s qualifications with the reliability of his

conclusions. While, as we stated supra, Dr. Morgan’s qualifications are not at issue, even the most

                                              –10–
qualified expert is still required to show his opinion does not have an analytical gap. Gammill at

727. While Dr. Morgan has undoubtedly observed many post-operative complications, his

observations led him to the conclusion that six different things could have caused the foot drop.

Allowing him to make the leap to his conclusion that, based only on an MRI taken 8 months post-

surgery, it was a post-operative hematoma compressing the nerve that caused the foot drop, would

ignore the obvious analytical gaps and promote decision making on a well-informed hunch.

           Oliver also relies on Transcon. Ins. Co. v. Crump, 330 S.W.3d 211, 215–16 (Tex. 2010) to

argue that courts have found the differential diagnosis method used by Dr. Morgan to be reliable

in determining causation.7 She contends that under Crump, while it is the sponsor’s burden to

bring forth sufficient evidence to establish the reliability of the expert once challenged, without

evidence that the alternative causes Dr. Morgan listed could be negated, the trial court had no basis

for concluding that Oliver did not meet his burden under the differential diagnosis framework.

Oliver does not direct us to any authority requiring a defendant to show that the extant alternative

possible causes could be negated, and we have found none. The Supreme Court has held that any

methodology that fails to rule out other viable possible causes for a plaintiff’s symptoms does not

satisfy the Robinson requirements. See Havner, 953 S.W.2d at 720 (“Further, if there are other

plausible causes of the injury or condition that could be negated, the plaintiff must offer evidence

excluding those causes with reasonable certainty”); Robinson, 923 S.W.2d at 558–59 (“Dr.

Whitcomb conducted no testing to exclude other possible causes of the damage to the Robinsons’

pecan orchard, even though he admitted in his deposition that many of the symptoms could be

caused by something other than contaminated Benlate.”). As Dr. Morgan himself acknowledged,

non-negligent results of spinal surgery could result in foot drop. There was also evidence before



      7
        Before the trial court and before this Court the parties argue multiple things about the differential diagnosis and Dr. Morgan’s use of it in
this case. We find it unnecessary to discuss the merits of those arguments here and decline to do so, as our conclusion may be reached without
such a discussion.

                                                                      –11–
the court that Oliver suffered from cervical myelopathy and Parkinson’s disease, and that each of

these conditions can cause clumsiness and difficulty with one’s gait. Although Dr. Morgan never

personally examined Oliver, he admitted that the physicians who had examined her had reached

these conclusions and he had no reason to disregard those diagnoses.

       In light of the analytical gaps and internal inconsistencies in Dr. Morgan’s testimony, we

conclude the trial court did not abuse its discretion in excluding Dr. Morgan’s expert testimony.

We are unpersuaded by Oliver’s arguments to the contrary. The record shows the trial court

considered and applied the guiding rules and principles applicable to the reliability of expert

witness testimony. See Gammill, 972 S.W.2d at 727; Robinson, 923 S.W.2d at 556–57.

                                        SUMMARY JUDGMENT

       Oliver properly concedes that absent Dr. Morgan’s opinion testimony there is no evidence

available in the summary judgment record to support a reversal. See JLG Trucking, LLC v. Garza,

466 S.W.3d 157, 162 (Tex. 2015). Because Oliver had no expert evidence of the causation of his

injuries, the trial court did not err by granting Dr. Saadi’s no-evidence motion for summary

judgment. See id.

                                             CONCLUSION

       We overrule Oliver’s sole issue and affirm the trial court’s judgment.




                                                 /David J. Schenck/
                                                 DAVID J. SCHENCK
                                                 JUSTICE


171403F.P05




                                              –12–
                               Court of Appeals
                        Fifth District of Texas at Dallas
                                       JUDGMENT

 EDWINA OLIVER, Appellant                            On Appeal from the 162nd Judicial District
                                                     Court, Dallas County, Texas
 No. 05-17-01403-CV          V.                      Trial Court Cause No. DC-15-07763.
                                                     Opinion delivered by Justice Schenck.
 PAUL SAADI, M.D., Appellee                          Justices Osborne and Reichek participating.

     In accordance with this Court’s opinion of this date, the judgment of the trial court is
AFFIRMED. It is ORDERED that each party bear its own costs of this appeal.


Judgment entered this 30th day of August, 2019.




                                              –13–
