Douglas C. Kilpatrick v. Breg, Inc. ( 2010 )


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  •                                                                                   [PUBLISH]
    IN THE UNITED STATES COURT OF APPEALS
    FOR THE ELEVENTH CIRCUIT
    ________________                           FILED
    U.S. COURT OF APPEALS
    No. 09-13813                   ELEVENTH CIRCUIT
    AUGUST 12, 2010
    ________________
    JOHN LEY
    CLERK
    D.C. Docket No. 08-10052-CV-KMM
    DOUGLAS C. KILPATRICK,
    Plaintiff-Appellant,
    versus
    BREG, INC.,
    a California Corporation
    for profit,
    Defendant-Appellee.
    ___________________
    Appeal from the United States District Court
    for the Southern District of Florida
    ___________________
    (August 12, 2010)
    Before BIRCH and MARCUS, Circuit Judges, and HODGES,* District Judge.
    *Honorable Wm. Terrell Hodges, U. S. District Judge for the Middle District of Florida, sitting
    by designation.
    HODGES, District Judge:
    This is a negligence and products liability action involving the use of a pain
    pump manufactured by Breg, Inc. for use during and after surgery. The Plaintiff,
    Douglas Kilpatrick, claiming to have been injured by one of Breg’s pumps,
    proffered a single expert witness on the issue of causation – Dr. Gary Poehling,
    M.D. The district court determined that the methodology used by Dr. Poehling to
    reach his conclusions was unreliable and, therefore, his testimony was
    inadmissible under Federal Rule of Evidence 702 and Daubert v. Merrell Dow
    Pharmaceuticals, 
    509 U.S. 579
    (1993). Without the testimony of Dr. Poehling, the
    district court further determined that Kilpatrick could not establish the causation
    element in any of his claims, and final summary judgment was granted in favor of
    Breg.1
    Kilpatrick appeals the exclusion of Dr. Poehling’s testimony. Upon a
    review of the record and this Circuit’s precedent establishing a highly deferential
    standard of review applicable to evidentiary determinations, we find that the
    district court did not abuse its discretion in excluding Dr. Poehling’s testimony.
    We therefore affirm.
    1
    Kilpatrick conceded that absent the expert testimony of Dr. Poehling, summary judgment
    was proper.
    2
    I. Background Facts and Procedural History
    On October 5, 2004, Kilpatrick underwent arthroscopic surgery on his right
    shoulder to repair a tear of his labrum, the ring of tissue that surrounds the
    shoulder socket, or glenoid. In an attempt to alleviate post-operative pain,
    Kilpatrick’s surgeon inserted into Kilpatrick's shoulder joint a pain pump
    manufactured by Breg. The catheter of the pump was implanted intra-articularly
    (within the joint space). Over the next 48 hours, the pain pump delivered 120 cc's
    of the anesthetic .5% bupivacaine (trade name Marcaine) into Kilpatrick's
    shoulder.2
    At the time of his surgery in 2004, Kilpatrick was 35 years of age and was a
    world class flats fishing guide in the Florida Keys. He returned to work for the
    2005 fishing season. While working, Kilpatrick noticed some popping in his right
    shoulder, but felt better at the end of the season. During the 2006 season,
    Kilpatrick began to experience severe shoulder pain and limited motion while
    working. Kilpatrick returned to his surgeon who conducted additional testing and,
    in October 2006, diagnosed glenohumeral chondrolysis – a complete breakdown
    2
    It is undisputed that Breg manufactured the pain pump but did not manufacture the
    bupivacaine.
    3
    of the cartilage in Kilpatrick's shoulder joint.3 On November 13, 2006, another
    orthopedic surgeon performed a total shoulder replacement for Kilpatrick, and
    Kilpatrick claims that he will have to undergo several more such procedures
    during his lifetime.
    On July 28, 2008, Kilpatrick filed a six-count complaint against Breg. Four
    of his claims assert theories of strict product liability for design defect, defect due
    to inadequate warning, defect due to nonconformance with representations, and
    defect due to failure to adequately test. Kilpatrick also asserted a negligence
    claim, and a claim for violation of the Florida Deceptive and Unfair Trade
    Practices Act, §§501.201-213, Florida Statutes. Kilpatrick alleges that, as a direct
    result of being administered bupivacaine using Breg's pain pump, he now suffers
    from debilitating shoulder pain and a permanent injury that has severely and
    negatively impacted his ability to work, resulting in economic harm including past
    and future medical expenses.
    3
    The Parties agree that glenohumeral chondrolysis – the complete destruction of the
    cartilage of the shoulder joint – is a medical phenomenon that has emerged only recently, and
    that the first study suggesting its linkage with intra-articular pain catheters appeared as recently
    as 2006.
    4
    In April 2009, Kilpatrick disclosed Dr. Poehling as his sole expert on
    general and specific causation.4 Dr. Poehling opined that the use of intra-articular
    pain pumps to dispense anesthetic directly to the shoulder joint can cause
    glenohumeral chondrolysis, and that the use of Breg’s pain pump in this manner
    caused Kilpatrick’s injuries. Following Dr. Poehling’s deposition, Breg filed a
    motion to exclude his testimony, and a motion for summary judgment on the
    ground that Kilpatrick had not sufficiently demonstrated that Breg's pain pump
    could and did cause the type of injury Kilpatrick suffered.
    On June 26, 2009, the district court granted Breg’s motions and dismissed
    Kilpatrick’s case with prejudice. The district court found that Dr. Poehling was
    qualified to testify as an expert,5 but that his causation testimony was scientifically
    unreliable and therefore inadmissable under Fed. R. Evid. 702. In particular, the
    4
    In order to prevail on his products liability claims, Kilpatrick must offer proof of both
    general causation – that the device in question can cause harm of the type Kilpatrick alleges –
    and proof of specific causation – that the device in fact did cause Kilpatrick’s injury. See
    McClain v. Metabolife Int’l, Inc., 
    401 F.3d 1233
    , 1239 (11th Cir. 2005). To meet this burden
    requires the use of expert testimony.
    5
    Dr. Poehling is an accomplished Board Certified orthopedic surgeon, author, professor,
    teacher, and lecturer. Since 1992 he has been the Editor In Chief of Arthroscopy – The Journal
    of Arthroscopic and Related Surgery, a major, peer-reviewed scientific publication. He has
    served as an advisory editor of the Shoulder Joint and Axilla section of Elsevier’s Interactive
    Anatomy Journal, and was the Chairman of the Department of Orthopedic Surgery at the
    Bowman Gray School of Medicine at Wake Forest University from 1989 to 2007. There is no
    question that he was qualified to testify as an expert.
    5
    district court found after thorough discussion and analysis that: (1) the medical
    literature on which Dr. Poehling based his conclusions did not reliably support his
    general causation opinion; (2) Dr. Poehling did not reliably consider the true
    background risk for glenohumeral chondrolysis; (3) Dr. Poehling’s concessions
    about the hypothetical and speculative nature of the medical science on the cause
    of chondrolysis “seriously undermine[d]” the reliability of his methodology; (4)
    Dr. Poehling’s use of the “differential diagnosis” methodology to determine
    specific causation was flawed because it presumed the existence of general
    causation; and (5) Dr. Poehling’s opinion on specific causation was improperly
    based solely on a temporal relationship between the use of Breg’s pain pump and
    Kilpatrick’s injuries.
    On July 15, 2009, the district court entered final judgment in favor of Breg.
    This appeal followed.
    II. Standard of Review
    This Court reviews a trial court’s decision to exclude an expert’s testimony
    pursuant to Daubert under an abuse of discretion standard. General Elec. Co. v.
    Joiner, 
    522 U.S. 136
    , 140 (1997); McClain v. Metabolife Int’l, Inc., 
    401 F.3d 1233
    , 1238 (11th Cir. 2005); Rink v. Cheminova, Inc., 
    400 F.3d 1286
    , 1291 (11th
    Cir. 2005). “This standard of review requires that we defer to the district court’s
    6
    ruling unless it is ‘manifestly erroneous.’” 
    Rink, 400 F.3d at 1291
    (quoting Quiet
    Tech. DC-8, Inc. v. Hurel-Dubois UK Ltd., 
    326 F.3d 1333
    , 1340 (11th Cir. 2003)).
    “Because the task of evaluating the reliability of expert testimony is uniquely
    entrusted to the district court under Daubert . . . we give the district court
    ‘considerable leeway’ in the execution of its duty.” 
    Id. (quoting Kumho
    Tire Co.,
    Ltd. v. Carmichael, 
    526 U.S. 137
    , 152 (1999)). This deferential standard is not
    relaxed even though a ruling on the admissibility of expert evidence may be
    outcome determinative. 
    Joiner, 522 U.S. at 142-43
    .
    In addition, we note that “[t]he burden of laying the proper foundation for
    the admission of expert testimony is on the party offering the expert, and the
    admissibility must be shown by a preponderance of the evidence.” McCorvey v.
    Baxter Healthcare Corp., 
    298 F.3d 1253
    , 1256 (11th Cir. 2002) (quoting Allison v.
    McGhan Med. Corp., 
    184 F.3d 1300
    , 1306 (11th Cir. 1999)).
    III. The Daubert Standard
    Daubert requires that trial courts act as “gatekeepers” to ensure that
    speculative, unreliable expert testimony does not reach the 
    jury. 589 U.S. at 597
    ,
    n. 7. The trial court must “make certain that an expert, whether basing testimony
    upon professional studies or personal experience, employs in the courtroom the
    7
    same level of intellectual rigor that characterizes the practice of an expert in the
    relevant field.” 
    Kumho, 526 U.S. at 152
    .
    Federal Rule of Evidence 702 governs the admission of expert testimony in
    federal court, and provides that:
    If scientific, technical, or other specialized knowledge
    will assist the trier of fact to understand the evidence or
    to determine a fact in issue, a witness qualified as an
    expert by knowledge, skill, experience, training, or
    education, may testify thereto in the form of an opinion
    or otherwise, if (1) the testimony is based upon sufficient
    facts or data, (2) the testimony is the product of reliable
    principles and methods, and (3) the witness has applied
    the principles and methods reliably to the facts of the case.
    Applying these principles, this Court has previously held that expert
    testimony may be admitted if three requirements are met. First, the expert must be
    qualified to testify competently regarding the matter he or she intends to address.
    Second, the methodology used must be reliable as determined by a Daubert
    inquiry. Third, the testimony must assist the trier of fact through the application of
    expertise to understand the evidence or determine a fact in issue. Tuscaloosa v.
    Harcros Chemicals, Inc., 
    158 F.3d 548
    , 562 (11th Cir. 1988).
    This case hinges on whether the methodology used by Dr. Poehling was
    reliable under Daubert. In deciding the question of reliability, the Supreme Court
    articulated a non-exhaustive list of relevant factors to consider: (1) whether the
    8
    expert’s theory can be and has been tested; (2) whether the theory has been
    subjected to peer review and publication; (3) the known or potential rate of error
    of the particular scientific technique; and (4) whether the technique is generally
    accepted in the scientific community. 
    Daubert, 509 U.S. at 593-94
    ; 
    McCorvey, 298 F.3d at 1256
    . The court must do “a preliminary assessment of whether the
    reasoning or methodology underlying the testimony is scientifically valid and of
    whether that reasoning or methodology properly can be applied to the facts in
    issue.” 
    Daubert, 509 U.S. at 593-94
    .
    IV. Dr. Poehling’s Testimony
    Kilpatrick first argues that the district court improperly focused on Dr.
    Poehling’s conclusions instead of his methodology. This argument is simply
    without merit; even a cursory review of the district court’s lengthy and detailed
    decision refutes the claim.6 The district court focused exclusively on the materials
    and methods Dr. Poehling used to form his opinions (i.e. his methodology). This
    is exactly what the district court was supposed to do.
    Kilpatrick next contends that because the methods Dr. Poehling used to
    reach his conclusions (reviewing medical literature and the “differential diagnosis”
    6
    See Kilpatrick v. Breg, Inc., No. 08-10052-CIV, 
    2009 WL 2058384
    (S.D. Fla. Jun. 25,
    2009).
    9
    methodology)7 were not new or novel, the district court should have refrained
    from assessing the reliability of these methods and should have focused solely on
    whether Dr. Poehling was qualified to testify as an expert – testimony that would
    have been helpful to the jury. Such an approach goes against the law of this
    Circuit, which has reversed trial courts who abdicate their gatekeeper role and
    refuse to assess reliability. See 
    McClain, 401 F.3d at 1238
    . To be sure, there are
    instances in which a district court may determine the reliability prong under
    Daubert based primarily upon an expert’s experience and general knowledge in
    the field, e.g., United States v. Brown, 
    415 F.3d 1257
    (11th Cir. 2005); but at all
    times the district court must still determine the reliability of the opinion, not
    merely the qualifications of the expert who offers it. See Kumho 
    Tire, 526 U.S. at 149
    (“We conclude that Daubert’s general principles apply to the expert matters
    described in Rule 702. The Rule, in respect to all such matters, establishes a
    standard of evidentiary reliability.”); see also Rider v. Sandoz Pharmaceuticals
    Corp., 
    295 F.3d 1194
    , 1197 (11th Cir. 2002) (noting that the Supreme Court in
    Kumho “made it clear that testimony based solely on the experience of an expert
    would not be admissible.”).
    7
    The “differential diagnosis” methodology “is a standard scientific technique of
    identifying the cause of a medical problem by eliminating the likely causes until the most
    probable one is isolated.” Westberry v. Gislaved Gummi AB, 
    178 F.3d 257
    , 262 (4th Cir. 1999).
    10
    Dr. Poehling testified that he formed his opinions after reviewing medical
    literature and applying the differential diagnosis method. Thus, it was entirely
    proper – indeed necessary – for the district court to focus on the reliability of these
    sources and methods. To hold otherwise would encourage trial courts to simply
    rubber stamp the opinions of expert witnesses once they are determined to be an
    expert. See Allison v. McGhan Medical Corp., 
    184 F.3d 1300
    , 1316-17 (11th Cir.
    1999) (“Under the regime of Daubert . . . a district judge asked to admit scientific
    evidence must determine whether the evidence is genuinely scientific, as distinct
    from being unscientific speculation offered by a genuine scientist.”).
    A.     General Causation Testimony
    Dr. Poehling testified at his deposition that the use of pain pumps to
    administer bupivacaine intra-articularly can cause glenohumeral chondrolysis. In
    reaching this conclusion, Dr. Poehling admitted that he did not conduct any tests
    himself, and did not rely on any epidemiological studies of human beings that
    connect intra-articular pain pumps or the use of bupivacaine with glenohumeral
    chondrolysis.8 The absence of such evidence is not fatal, but makes his task to
    show general causation more difficult. See 
    Rider, 295 F.3d at 1198-99
    . In
    8
    “Epidemiology, a field that concerns itself with finding the causal nexus between
    external factors and disease, is generally considered to be the best evidence of causation in toxic
    tort actions.” 
    Rider, 295 F.3d at 1198
    .
    11
    particular, the basic methodology employed to reach the conclusions must be
    reliable and sound. Wells v. Ortho Pharmaceutical Corp., 
    788 F.2d 741
    , 745 (11th
    Cir. 1986) (citing Ferebee v. Chevron Chemical Co., 
    736 F.2d 1529
    , 1535-36
    (D.C. Cir. 1984)).9
    Dr. Poehling reviewed five sources to make his general causation
    assessment. All of the sources are articles from various medical journals, none of
    which were based on epidemiological studies. The district court considered four
    of these items of literature both separately and in combination, and found them
    insufficient to satisfy the reliability requirement of Fed. R. Evid. 702.
    The district court began by looking at the articles in combination and noted
    that only one of the articles was a comparative study of humans who had
    undergone arthroscopic surgery involving pain pumps. None of the articles
    explained the mechanism by which bupivacaine damages cartilage, and none of
    them offered an ultimate conclusion as to the general causation of glenohumeral
    chondrolysis in humans. A review of these articles confirms the district court’s
    findings, and Kilpatrick does not dispute them.
    9
    Kilpatrick’s argument that conducting any epidemiological studies would be unethical,
    because it would require the potential destruction of a person’s shoulder cartilage, has some
    merit. But in the absence of such studies, the nature of the other evidence (case reports, animal
    studies, in vitro studies) becomes that much more important, and the court’s consideration of
    such evidence and the methodologies used must be that much more searching.
    12
    1.     The Hansen Study
    The district court first considered a 2007 article from the American Journal
    of Sports Medicine (the “Hansen study”).10 The Hansen study analyzed the
    medical records of 152 patients who had undergone 177 arthroscopic shoulder
    surgeries. Of these 152 patients, only nineteen shoulders in seventeen patients had
    bupivacaine-dispensing pain pumps inserted into them, and of those, only twelve
    shoulders in ten patients developed chondrolysis. According to Dr. Poehling, this
    63% (twelve out of nineteen shoulders) incidence of chondrolysis was the
    “strongest” evidence of a connection between intra-articular pain pumps and
    chondrolysis.
    The district court concluded that the Hansen study was unreliable because it
    did not include any statistical analysis and did not explain whether it was
    statistically meaningful to extrapolate from such a small sample size. The study
    also did not account for other causes of chondrolysis – specifically noting that “[i]t
    is likely that other unrecognized factors are also involved. . . . [and that other
    factors] may have played a role not yet completely understood at this time.” The
    study also failed to explain why seven of the patients (almost 40%) treated with
    10
    Brent P. Hansen et al., Postarthroscopic Glenohumeral Chondrolysis, 35 Am. J. Sports
    Med. 1628-34 (July 2007). The Hansen study was first presented in 2006 to the American
    Academy of Orthopedic Surgery.
    13
    pain pumps did not develop chondrolysis – a result that Dr. Poehling himself
    could not explain. More importantly, the study did not reach a conclusion as to
    the general causation of chondrolysis, stating that “[n]o etiology [of chondrolysis]
    has been firmly identified . . .” and that further research was needed. All that the
    authors were able to state was that pain pumps eluting Marcaine “appear highly
    associated with post-arthroscopic glenohumeral chondrolysis.”
    In sum, the Hansen study was merely a compilation of case reports without
    any statistical context. Such studies “lack control[] and thus do not provide as
    much information as controlled epidemiological studies do . . . Causal attribution
    based on case studies must be regarded with caution.” 
    McClain, 401 F.3d at 1253
    (internal citations omitted). See also 
    Rider, 295 F.3d at 1199
    (“[W]hile they may
    support other proof of causation, case reports alone ordinarily cannot prove
    causation.”).
    Faced with a study that failed to explain why 40% of patients treated with
    intra-articular pain pumps did not develop chondrolysis, the lack of any statistical
    analysis discussing the relative importance of this study, the failure to account for
    other causes of chondrolysis, and the omission of any conclusion on general
    causation, the district court did not abuse its discretion in finding that the Hansen
    study was not a source upon which Dr. Poehling could reasonably rely under Fed.
    14
    R. Evid. 702. Kilpatrick’s focus on the authors’ description of an “association”
    between pain pumps and glenohumeral chondrolysis is unavailing. “[S]howing
    [an] association is far removed from proving causation.” 
    Allison, 184 F.3d at 1315
    n. 16 (emphasis in original).
    2.     The Gomoll Study
    The district court next considered a 2006 article discussing a controlled
    study of rabbits (the “Gomoll study”).11 The authors of this study administered
    Marcaine to live rabbits continuously through a catheter over 48 hours, while
    other rabbits received saline over the same time period. The animals were
    euthanized one week later and their cartilage was examined.
    The authors of the Gomoll study concluded that “[c]ontinuous intra-articular
    infusion of bupivacaine (Marcaine), with and without epinephrine, led to
    significant histopathologic and metabolic changes in articular cartilage.”
    However, the authors were careful to limit this conclusion to rabbits, and did not
    extrapolate their findings to humans, noting that further study was warranted:
    One limitation of our study, which it shares with most
    animal models, should be considered; although we were
    able to show the detrimental effects of bupivacaine on
    11
    Andres Gomoll et al., Chondrolysis After Continuous Intra-Articular Bupivacaine
    Infusion: An Experimental Model Investigating Chondrotoxicity in the Rabbit Shoulder, 22
    Arthroscopy 813-19 (August 2006).
    15
    the cellular and tissue level in a rabbit model, it remains
    to be determined whether human cartilage is equally
    susceptible and whether these histopathologic and
    functional changes result in the subsequent development
    of rapidly progressive osteoarthritis . . . . Because
    epidemiologic study of chondrolysis in humans will
    require an extremely large sample size because of the
    low incidence and prevalence of this condition,
    additional studies in larger animal model with longer-
    term follow-up, as well as in vitro studies with
    continuous exposure of human cartilage to bupivicaine,
    are necessary to provide further understanding.
    Thus, by its own words, the Gomoll study at most suggests a connection between
    the use of intra-articular pain pumps, bupivacaine, and chondrolysis in rabbit
    cartilage. This does not equate to a conclusion of direct causation (or a connection
    of any degree) between the use of such pain pumps and chondrolysis in humans.
    The authors of the Gomoll study further acknowledged that “no data exists
    regarding the human-equivalent dosing of intra-articular bupivacaine in a rabbit
    shoulder model. . . .” Dr. Poehling also could not explain the possible differences
    in dose-response relationship between humans and rabbits. As the district court
    correctly noted, a dose-response relationship is “the single most important factor
    to consider in evaluating whether an alleged exposure caused a specific adverse
    effect.” 
    McClain, 401 F.3d at 1242
    (citing David Eaton, Scientific Judgment and
    Toxic Torts: A Primer in Toxicology for Judges and Lawyers, 
    12 Johns. L
    . & Pol’y 1,
    16
    11 (2003)).12 The lack of any data or any explanation by Dr. Poehling on this
    point puts the methodology of both the Gomoll study, and Dr. Poehling’s general
    causation opinions in question. “The expert who avoids or neglects [the dose-
    response] principle of toxic torts without justification casts suspicion on the
    reliability of his methodology.” 
    McClain, 401 F.3d at 1242
    .
    The district court did not abuse its discretion in finding the Gomoll study
    unreliable under Fed. R. Evid. 702. See 
    Joiner, 522 U.S. at 144-45
    (finding no
    abuse of discretion where the trial court rejected an expert’s reliance on animal
    studies that were dissimilar to the facts of the case).
    3.     The Greis Report
    The third article the district court addressed was a 2008 case study of two
    teenage female swimmers who underwent arthroscopic surgery and subsequently
    developed chondrolysis (the “Greis report”).13 Both patients received bupivacaine
    using intra-articular pain pumps following surgery. The district court found this
    study to be unreliable for two reasons. First, the study only analyzed these two
    patients’ specific cases – there was no statistical analysis and the study did not
    12
    Dose-response relationship is “[a] relationship in which a change in amount, intensity,
    or duration of exposure to an agent is associated with a change – either an increase or decrease –
    in risk of disease.” 
    McClain, 401 F.3d at 1242
    -42 (citations omitted).
    13
    Patrick Greis et al., Bilateral Shoulder Chondrolysis Following Arthroscopy: A Report
    of Two Cases, 90 J. Bone & Joint Surgery 1338-44 (June 2008).
    17
    draw any medically valid conclusions. The district court’s decision comports with
    the law of this Circuit. 
    McClain, 401 F.3d at 1254
    (“case reports raise questions;
    they do not answer them.”); 
    Rider, 295 F.3d at 1199
    (“courts must consider that
    case reports are merely accounts of medical events. They reflect only reported
    data, not scientific methodology.”). Indeed, Dr. Poehling himself acknowledged
    that case reports such as the Greis report are “way down at the very bottom as far
    as medical strength of an article” and cannot establish medical causation.
    The district court also found fault with placing reliance upon the Greis
    report because it expressly recognized that “the exact cause of the chondrolysis
    remains unknown” and listed a multitude of factors that could have caused these
    patients’ chondrolysis. The report went on to hypothesize about the various
    factors, without drawing any conclusions. As a result, the district court found that
    Dr. Poehling’s dependence upon an anecdotal case report to conclude that intra-
    articular pain pumps administering bupivacaine generally causes chondrolysis
    could not satisfy the reliability standards of Fed. R. Evid. 702. The court finds no
    error in this determination.
    18
    4.    The Lubowitz Editorial
    Lastly, the district court considered a one-page editorial that Dr. Poehling
    co-authored with Dr. James Lubowitz (the “Lubowitz editorial”) in 2007.14 The
    editorial is not a case report or study but, as Dr. Poehling admitted “is general in
    nature and does not present any factual context that would allow the court to
    discern its relevance to this case.” The very title of the editorial states the need for
    further research.
    With respect to the causes of glenohumeral chondrolysis, the Lubowitz
    editorial stated that “[t]he etiology of glenohumeral chondrolysis may be
    multifactorial. Future research is required to determine the cause, and proper
    prevention, of shoulder chondrolysis.” Dr. Poehling admitted that this statement
    remained correct two years later at the time of his deposition. The editorial also
    recognized the existence of chondrolysis caused by unknown factors –
    “idiopathic” chondrolysis. As Dr. Poehling himself admitted, this editorial is
    clearly inadequate as a basis for a scientific judgment about the general causation
    of chondrolysis.
    14
    James Lubowitz & Gary Poehling, Editorial: Glenohumeral Thermal Capsulorrhaphy Is
    Not Recommended – Shoulder Chondrolysis Requires Additional Research, 23 Arthroscopy 687
    (July 2007).
    19
    5.    The District Court’s Conclusion
    The district court exercised its discretion and found that each of these
    articles, both taken together and separately, were not sufficiently reliable to
    support Dr. Poehling’s opinion on general causation. Kilpatrick challenges the
    district court’s findings with respect to this literature on several grounds. First,
    Kilpatrick claims that the articles do in fact establish a direct causal link between
    the use of intra-articular pain pumps to dispense bupivacaine and chondrolysis.
    As the district court concluded, however, this argument is belied both by the plain
    language of the articles and by Dr. Poehling’s own testimony that none of the
    articles he relied upon – indeed no literature in existence at the time of his
    deposition – establishes such a direct causal link. Dr. Poehling’s admission that
    the literature is speculative in nature is by itself sufficient to warrant a finding of
    unreliability.
    Second, Kilpatrick lists seven additional articles and studies that he
    contends Dr. Poehling relied upon in reaching his conclusions, and which the
    district court wrongfully failed to take into account. According to Kilpatrick,
    these other articles conclusively establish a direct causal link between the use of
    intra-articular pain pumps, bupivacaine, and chondrolysis. On this point,
    Kilpatrick is partially correct – a review of Dr. Poehling’s deposition testimony
    20
    shows that he mentioned one additional article – a January 2008 study of cow and
    human cartilage by Dr. Constance Chu and others (the “Chu study”).15 However,
    this study suffers from the same deficiencies as the Gomoll study – the authors of
    the Chu study noted that their “in vitro assessments do not account for dilutional
    effects or in vivo reparative processes.”16 The Chu study went on to state that “in
    vitro results cannot be directly extrapolated to clinical practice” and concluded
    that “the in vitro bovine chondrocyte data . . . support the need for comprehensive
    additional studies.” In other words, the authors could not state how their test
    results would transfer when conducted on a live human subject.
    Thus, even if the district court had considered the Chu study together with
    the other four pieces of literature it examined, it is clear that the court would not
    have altered its conclusion. See 
    Allison, 184 F.3d at 1313-14
    (affirming exclusion
    of causation testimony based upon animal studies because the expert “failed to
    explain the correlation of the results of Lightfoote’s rat studies in which the rats
    were directly injected with silicone to symptoms in a human patient.”). One
    additional animal study discussing the differences between in vitro and in vivo
    15
    Constance Chu, et al., The In Vitro Effects of Bupivacaine on Articular Chondrocytes,
    90 J. Bone & Joint Surg. 814, 820 (Jan. 2008).
    16
    “In vitro” refers to procedures performed in a controlled environment, such as a test
    tube or petri dish. “In vivo” studies refers to experiments using an entire, living organism, such
    as a live human subject.
    21
    results, and the need for further studies does not come close to satisfying Rule
    702's reliability requirements, and does not establish an abuse of discretion on the
    part of the district court.17
    The other six articles Kilpatrick lists in his brief are nowhere mentioned in
    Dr. Poehling’s deposition testimony despite extensive and repeated requests by
    Breg’s counsel exhorting Dr. Poehling to identify every single article and study he
    relied upon. Instead, Kilpatrick points to a statement by Dr. Poehling at his
    deposition that he considered various other articles which were on his computer at
    home. Such a vague reference to other unnamed articles is not sufficient to
    support Dr. Poehling’s conclusion on general causation, and does not render his
    methodology reliable. Dr. Poehling had ample opportunity to identify all of the
    bases for his conclusions and to explain his methodology in reaching those
    conclusions. It was not an abuse of discretion for the district court to ignore
    allusions to other articles.
    Last, Kilpatrick argues that the district court erred when it considered each
    identified piece of literature separately, rather than in combination. First, it is
    17
    While the district court did not specifically identify the Chu study in its order, the trial
    court did state that it reviewed the entire voluminous record in this case, including Dr. Poehling’s
    expert report, his deposition testimony, and the medical literature upon which he based his
    opinions. Thus, it is not entirely clear that the district court ignored the Chu study, and in any
    event, the district court did not abuse its discretion.
    22
    clear that the district court did consider all of the articles together, and specifically
    considered Dr. Poehling’s own admission that no literature exists concluding that
    intra-articular pain pumps are the cause of glenohymeral chondrolysis. Rather, all
    of the articles merely stated potential associations and speculated that such pain
    pumps medically cause glenohumeral chondrolysis. The district court also noted
    that none of the articles explained the mechanism by which bupivacaine damaged
    human cartilage. The fact that the district court then further analyzed each article
    in detail and found each to be unreliable was a proper approach to the issue. See
    
    Joiner, 522 U.S. at 145-46
    .
    In summary, the district court did not abuse its discretion in finding that the
    literature Dr. Poehling based his conclusions upon was insufficient to create a
    reliable methodology which passes Daubert muster. See 
    McClain, 401 F.3d at 1245
    (“[t]he Daubert requirement that the expert testify to scientific knowledge –
    conclusions supported by good grounds for each step in the analysis – means that
    any step that renders the analysis unreliable under the Daubert factors renders the
    expert’s testimony inadmissible.”) (internal citations and quotations omitted).18
    18
    The court does not intend to suggest that in order to survive Daubert review, a
    methodology based on a review of existing literature on the subject must rely on articles that
    draw a direct, concrete, and absolute causal connection. However, in this case, given the paucity
    of reliable evidence and the speculative nature of the articles Dr. Poehling relied upon, the court
    cannot disagree to the point of finding an abuse of discretion in the district court’s conclusion
    (continued...)
    23
    6.     Background Risk
    The district court was further persuaded by the fact that none of the articles
    took into account the background risks for chondrolysis: “[t]he risk a plaintiff and
    other members of the general public have of suffering the disease or injury that
    plaintiff alleges without exposure to the drug or chemical in question.” 
    McClain, 401 F.3d at 1243
    (emphasis in original). Several of the articles Dr. Poehling relied
    upon expressly noted that the cause of chondrolysis remains unknown, and that
    idiopathic causes could play a factor. Dr. Poehling ignored such background risks.
    While recognizing the existence of idiopathic (or unknown) causes of
    chondrolysis, he dismissed them by merely stating that the risk of idiopathic
    chondrolysis is essentially zero. The failure to take into account the potential for
    idiopathically occurring chondrolysis – particularly when glenohumeral
    chondrolysis is a relatively new phenomenon in need of further study – placed the
    reliability of Dr. Poehling’s conclusions in further doubt. 
    McClain, 401 F.3d at 1243
    -44 (“A reliable methodology should take into account the background
    risk.”).
    18
    (...continued)
    that Dr. Poehling’s methodology on general causation was not reliable for purposes of Rule 702.
    24
    B.    Specific Causation Testimony
    Dr. Poehling also opined that the continuous intra-articular infusion of
    bupivacaine through Breg’s pain pump caused Kilpatrick’s chondrolysis. When
    asked the basis for this conclusion, Dr. Poehling could point to nothing other than
    the literature and the temporal relationship between Kilpatrick’s initial surgery and
    his chondrolysis.
    . . . I think any scientist would sit down and look at this
    case and observe the factors of what happened to this
    patient, what he looked like before and what he looks
    like now would come to the conclusion that bipuvacaine
    is what caused it, and I don’t think that that’s just me or
    — I think any real scientist.
    Such specific causation testimony has been found to be inherently unreliable in
    this Circuit. 
    McClain, 401 F.3d at 1254
    (“[T]he temporal connection between
    exposure to chemicals and an onset of symptoms, standing alone, is entitled to
    little weight in determining causation. It is also subject to the problem of
    assuming what the witness is trying to prove.”).
    Dr. Poehling testified that he used the “differential diagnosis” methodology
    to find specific causation. This method involves a process of compiling, or ruling
    in, a comprehensive list of possible causes that are generally capable of causing
    the illness or disease at issue, and then systematically and scientifically ruling out
    25
    specific causes until a final, suspected cause remains. 
    McClain, 401 F.3d at 1253
    .
    It assumes the existence of general causation, and focuses instead on specific
    causation. The expert must show through reliable evidence that the remaining
    cause ruled in as actually being capable of causing the condition.
    Kilpatrick is correct that differential diagnosis itself has been recognized as
    a valid and reliable methodology. But that is not the issue about which the district
    court found fault. Rather, the district court found that Dr. Poehling’s application
    of this methodology was flawed. In order to correctly apply this methodology, Dr.
    Poehling must have complied a comprehensive list of potential causes of
    Kilpatrick’s injury and must have explained why potential alternative causes were
    ruled out. However, Dr. Poehling only ruled out two causes – thermal energy and
    gentian violet contrast dye. He clearly testified that he could not explain why
    potentially unknown, or idiopathic alternative causes were not ruled out. Dr.
    Poehling also admitted that neither he nor anyone else in the medical community
    “understands the physiological process by which [chondrolysis] develops and
    what factors cause the process to occur.” Thus, the key foundation for applying
    differential diagnosis was missing, and based on these deficiencies, the district
    court found that Dr. Poehling failed to apply the differential diagnosis
    methodology reliably. The district court did not abuse its discretion in so
    26
    concluding. 
    McClain, 401 F.3d at 1253
    (an “expert does not establish the
    reliability of his techniques or the validity of his conclusions simply by claiming
    that he performed a differential diagnosis on the patient.”).
    Kilpatrick cannot overcome the fact that Dr. Poehling’s specific causation
    testimony is rooted in a temporal relationship. “[P]roving a temporal relationship
    . . . does not establish a causal relationship . . . . [S]imply because a person takes
    drugs and then suffers an injury does not show causation.” 
    McClain, 401 F.3d at 1243
    (emphasis in original). This is a classic “post hoc ergo propter hoc” fallacy
    which “assumes causation from temporal sequence. It literally means ‘after that,
    because of this’ . . . . It is called a fallacy because it makes an assumption based
    on the false inference that a temporal relationship proves a causal relationship.”
    
    Id. Dr. Poehling
    made clear that he reached his conclusions with respect to
    Kilpatrick’s injuries merely by looking at Kilpatrick’s shoulder before and after
    the use of Breg’s pain pump. The district court did not abuse its discretion in
    finding Dr. Poehling’s methodology to establish specific causation unreliable
    under Daubert.
    V. Conclusion
    The district court conducted an exhaustive and thorough review of the
    evidence Kilpatrick submitted to support causation, and concluded that his expert
    27
    witness did not employ a reliable methodology to support his conclusions. This
    court has carefully reviewed the same evidence and finds that the district court did
    not abuse its broad judicial discretion in so holding. We are aware that courts in
    other circuits have taken a more expansive approach and permitted expert
    testimony in similar situations. See McClellan v. I-Flow Corp., ___ F. Supp. 2d
    ___, 
    2010 WL 1753261
    (D. Or. Apr. 29, 2010); Schott v. I-Flow Corp., ___ F.
    Supp. 2d ___, 
    2010 WL 1008478
    (S.D. Ohio Mar. 16, 2010). However,
    Kilpatrick’s briefs suffer from a paucity of binding precedent to support his
    position, and with good reason. The law of this Circuit is clear that the district
    courts are given broad discretion with wide latitude in conducting a
    Daubert analysis and concluding that methodologies based on speculative
    literature and temporal proximity analysis such as the type relied upon by Dr.
    Poehling are not sufficient to pass Daubert review.
    We have previously held that “the abuse of discretion standard allows ‘a
    range of choice for the district court, so long as that choice does not constitute a
    clear error of judgment.” Rasbury v. Internal Revenue Service (In re Rasbury), 
    24 F.3d 159
    , 168 (11th Cir. 1994) (quoting United States v. Kelly, 
    888 F.2d 732
    , 745
    (11th Cir. 1989)). The size of that range – particularly when dealing with
    evidentiary issues – is significant, and we defer to a district court’s evidentiary
    28
    rulings to a considerable extent. 
    Brown, 415 F.3d at 1265
    . In particular, the abuse
    of discretion standard “thrives” when addressing Daubert issues. 
    Id. at 1265-66.
    See Kumho 
    tire, 526 U.S. at 152-53
    ; United States v. Abreu, 
    406 F.3d 1304
    , 1305-
    07 (11th Cir. 2005); 
    McClain, 401 F.3d at 1238
    . Given the facts of this case, the
    law of this Circuit, and particularly in light of the deferential standard of review
    afforded district courts in these cases: “the heavy thumb – really a thumb and a
    finger or two – that is put on the district court’s side of the scale,” the court
    concludes that it was not an abuse of discretion to exclude the expert opinion of
    Dr. Poehling in this case. 
    Brown, 415 F.3d at 1268
    .
    AFFIRMED
    29