For almost thirty years, Timothy Myers worked for the Illinois Central Railroad Company. The work was physically demanding and over the course of his career Myers suffered several injuries, including cumulative trauma disorders that eventually forced him to retire. He sued the Railroad claiming that these disorders were caused by its negligence. Before trial, Myers offered reports from three medical doctors and an ergonomist that would prove the Railroad’s negligence caused his injuries. But the district court barred Myers’s experts and granted summary judgment for the Railroad. On appeal, Myers argues that the district court erred. Because the opinions of Myers’s physicians were based on speculation, and the nature of his injuries necessitates expert testimony about specific causation that the ergonomist could not provide, we affirm.
I.
Myers is 50 years old, and he began working for the Railroad after graduating from high school in 1978. Over the years, he worked in various capacities, including as a brakeman, a switchman, and a conductor. Since the early 1990s, the job titles brakeman, switchman, and conductor included the same employment tasks, and we use them interchangeably. Regardless of the title, Myers’s work was physically demanding. He would get on and off a slow-moving train 30 or 35 times a day and walk several miles every day on large, rocky ballast. Ballast is simply the rock that surrounds the train tracks. Sometimes the ballast was covered with bean meal or corn meal, which made it like walking through mud during the summer time and walking on ice in the winter. In addition to walking miles in those conditions, as many as 50 times a day Myers would throw the switch that changes tracks that a train is traveling on. And he would connect the handbrakes and pull the pins that connect the train cars. These tasks *641 varied in difficulty depending on the rail yard and the season.
Besides being physically demanding, this work was also dangerous. Myers fell off a tank car in 1981 and broke his right ankle and hurt his left knee, which required surgery. A few years later, he stepped on a large rock while he was getting off the train and injured his right knee. He had surgery on that knee too. Then in 1987, he injured his back after trying to move a four-hundred-pound draw bar, which is a device used for coupling a train car to the engine. As a result he missed three to five months of work. After that, Myers was injury-free until 1998 when he injured his knee and shoulder trying to force a cab door open. The knee improved with rest, but he had to have surgery on his shoulder.
Naturally these injuries and the nature of this work have taken a toll on Myers’s body. Between 2004 and 2006, he began to experience pain in his left elbow, his right knee, and his back and neck. The problem with his left elbow was diagnosed as a medial epicondylitis, which is commonly called “golfer’s elbow”; his right knee was diagnosed with osteoarthritis, which is commonly referred to as degenerative arthritis; and he had several serious problems with his back, including several herniated disks. Each problem required surgery — two, in the case of his back.
In 2008, he sued the Railroad under the Federal Employers’ Liability Act, 45 U.S.C. § 51, claiming that the Railroad’s failure to provide him with a reasonably safe workplace caused the problems with his elbow, knee, and back and neck. The physicians who treated Myers for each of these injuries were listed as experts and expected to testify at trial. Myers also expected to call an ergonomist, Dr. Tyler Kress, who would testify at trial about how the dangerous conditions in the Railroad’s yards could have caused Myers’s injuries.
Before trial, however, the district court struck the four experts. It found that under
Daubert v. Merrell Dow Pharmaceuticals,
II.
There are two issues here. The first is whether the district court erred by finding that Myers needed expert testimony to establish specific causation and granting summary judgment for the Railroad. The second is whether the district court correctly applied
Daubert
when it struck Myers’s physicians from giving expert testimony. We review de novo the granting of summary judgment.
Gayton v. McCoy,
III.
The primary question on appeal is whether Myers needs expert testimony to establish that the Railroad’s negligence specifically caused the cumulative trauma injuries to his knee, elbow, and back and neck. In the district court and here, Myers argues that he merely needs to have expert testimony establishing that the conditions at the Railroad can cause *642 the injuries that Myers suffers from. In support of this, Myers planned to call an ergonomist, Dr. Tyler Kress, to testify that the Railroad’s practices can cause the same ailments afflicting Myers.
The district court struck the ergonomist because he could not tie Myers’s work and the Railroad’s practices to Myers’s specific injuries. Myers argues that although Kress could not testify about what specifically caused his injuries, he could testify generally about the dangers that come with working in the Railroad’s yards. And from that alone, the jury could find that Myers’s injuries were caused by the Railroad. Thus, the issue Myers presents on appeal is not whether the ergonomist should have been excluded because he could not testify about the specifics of how Myers’s work caused his injury, but whether Kress’s general causation testimony is sufficient to survive summary judgment.
Debate continues over the issue of how plaintiffs must establish causation under FELA.
See Norfolk Southern Ry. Co. v. Sorrell,
These injuries are still very serious and possibly compensable under the Act. But “the Act did not make the employer an insurer. The liability which it imposed was the liability for negligence.”
Wilkerson,
While the plaintiff is obligated to prove some degree of negligence, the question remains whether expert testimony is required in that process. Expert testimony is unnecessary in cases where a layperson can understand what caused the injury.
See Wallace v. McGlothan,
Here, neither Myers nor his physicians could point to a specific injury or moment that brought on the problems with his knee, elbow, and back and neck. Instead, Myers claims that they are the product of years of working for the Railroad. That type of gradual deterioration is precisely what defines cumulative trauma injuries: “Cumulative trauma disorder refers not to one specific injury, but to numerous disorders caused by the performance of repetitive work over a long period of time.”
Gutierrez,
When an injury is of this nature, determining what caused it is not usually obvious to a layman and thus requires expert testimony. For most cumulative trauma injuries, courts follow the general principle that a layman could not discern the specific cause and thus they have required expert testimony about causation.
Brooks,
Here, the origin of Myers’s various injuries would not be obvious to a layman. They can be caused by a myriad of factors, none of which is obvious or certain.
Gutierrez,
To be clear, the ergonomist could testify as an expert about how dangerous the railroad yard’s conditions were, but that does not mean he is qualified to testify about what caused Myers’s injuries. This is a scenario similar to what many plaintiffs face in toxic tort cases: an expert can testify that a chemical can cause the plaintiffs malady but he may not be qualified to testify that
this
chemical caused
this
par
*644
ticular plaintiffs malady.
Claar,
Myers planned to establish that the Railroad’s negligence caused his injuries from testimony of his three treating physicians. Before trial, the Railroad moved to strike the experts’ testimony as unreliable under
Daubert.
Under Federal Rule of Evidence 702 and
Daubert,
the district court must engage in a three-step analysis before admitting expert testimony. It must determine whether the witness is qualified; whether the expert’s methodology is scientifically reliable; and whether the testimony will “assist the trier of fact to understand the evidence or to determine a fact in issue.”
Ervin v. Johnson & Johnson, Inc.,
Differential diagnosis is an accepted and valid methodology for an expert to render an opinion about the identity of a specific ailment.
Happel,
Other than Myers’s assertion that the physicians did a differential etiology, there is nothing in the record that suggests they did, or if it was done that it could be considered reliable, because they did not rule in any causes of Myers’s ailment, nor did they rule out anything. They simply opined that it was the Railroad’s working conditions that caused Myers’s ailment. Given the nature of Myers’s injury and his work, it seems natural to offer such an opinion. But the law demands more than a casual diagnosis that a doctor may offer a friend or acquaintance outside the office about what could be causing his aches and pains.
*645 The physicians’ deposition testimonies made it clear that they were clearly offering something less than a causation opinion that could qualify under Daubert. On this point, the physician who operated on Myers’s back did not know about Myers’s earlier back injury until after he rendered his opinion. When asked about what role Myers’s 1987 back injury would play in his current condition, the physician responded:
Well, I don’t really think that it makes a hell of a lot of difference one way or the other. You put your interest in what he has got wrong with him on the day you treat him. Now, if you are interested in causation, then from your standpoint, it’s important.
Another physician was also candid when questioned about the fact that he had not explored what Myers did at work and how that affected his causation opinion:
[Rjeally the thrust of my business is to find out what his problems are and what we think can be done about them. So, again, I’m seeing him as a medical doctor, not as a — you know, seeing him for a work history type charge. So, you know, my charge — I would have spent more time on that. Since that was not my charge, it was really just to get a rough idea of what things he did.
The physicians’ testimonies made it clear that they were offering a general medical opinion about his condition at the time of treatment and an assumption that it developed over time at the Railroad. Other than common sense, there was no methodology to their etiology.
If a differential etiology was used and the experts were unaware of aspects of his work or medical history, that doesn’t necessarily mean the expert should be struck. On this point, we have instructed that when a medical expert has “relied upon a patient’s self-reported history and that history is found to be inaccurate, district courts usually should allow those inaccuracies in that history to be explored through cross-examination.”
Walker v. Soo Line R.R. Co.,
IV.
Therefore, the nature of the trauma injuries that Myers accumulated required expert testimony establishing specific causation. The district court did not abuse its discretion by excluding the testimony of Myers’s physicians, and because that was the only evidence offered for specific causation, the district court did not err in granting summary judgment for the Railroad. Accordingly, the judgment of the district court is Affirmed.
