The employee claimed workers’ compensation benefits were payable as the result of physical conditions which he asserted were due to stress from his employment.  The compensation judge determined that the employee had established medical causation between the stress and the physical conditions, but concluded that the employee had failed to establish legal causation.  The compensation judge denied the employee’s claim and the employee appeals.  We affirm.

Robert Mager began working for the Minnesota Department of Transportation in 1979.  He has worked since that time at the Warren Truck Station in northwestern Minnesota where he has operated a variety of equipment such as mowers, graders and trucks.  During the winter months, his primary duty has been to operate a snowplow or grader in removing snow from roads.

The employee claimed at the hearing that stress from his employment resulted in the development of mitral valve prolapse disease and gastroesophageal reflux disease (GERD).  The employee was taken off work by a treating physician because of these conditions on December 6, 2002, and the employee alleged a Gillette^[1] injury as of that date.  The self-insured employer denied the employee’s claims, asserting that the employee’s physical conditions were not the result of employment related stress and that, in any event, any such stress was not at a level to establish legal causation under applicable case law.

As sources of his stress, the employee cited to three motor vehicle accidents in which he was involved while on the job.  On December 22, 1993, the plow on the truck the employee was operating got caught on railroad tracks he was crossing.  The plow broke the rear window of the truck and a bracket on the wing of the plow was bent.  The second accident occurred on February 28, 1996, when the blade on the grader the employee was driving struck a state truck being driven by a co-worker.  The third accident was on December 18, 1996.  In backing up a grader to put it in the shop, the employee struck a parked pick-up.  There were no personal injuries in any of these accidents.

The employee also testified that there were numerous unreported incidents in which his truck or grader struck unseen objects during snowy conditions.  The employee also referred to an incident where the drive shaft fell out of the truck he was driving.  No date was given for this incident.  The employee testified to increased anxiety following the motor vehicle accidents when he was faced with the probability of having to plow snow or drive equipment in inclement weather.  The possibility of an “early call out” when the employee would have to report for work at 3:00 A.M. to begin snowplowing also increased his anxiety.  The employee had chest pain and stomach discomfort associated with his anxiety.

The employee was first seen for symptoms of GERD on August 24, 2001, when he saw his family doctor, Dr. Peter Funk.  There was no mention of his employment in the history taken at that time.  He was placed on medication.  On November 2, 2001, he told Dr. Funk that “at times his heart flutters.”  A cardiology referral was made and a diagnosis of mitral valve prolapse was made.  There was no mention of psychological stress as a causative factor.  When he followed up with Dr. Funk on January 30, 2002, Dr. Funk stated, “we also did write him an excuse for him not to be driving a snowplow.  He thinks he is under too much stress and does not feel he can do it at this point.”

The first mention of anxiety disorder as a possible diagnosis is in the records of February 21, 2002, when the employee saw Dr. Funk in follow up for his GERD and mitral valve prolapse conditions.  In the history, Dr. Funk stated, “he has tried hard to forget about these problems, but they continue to bother him a great deal.^[2]  He was under a lot more stress earlier this winter when there was no snow on the ground.  He apparently works as an operator of a snowplow.  At this point, I think he can go back to his regular duties and we have released him for his normal job duties at this point.”  The employee was on medication for mitral prolapse disease and GERD.  The diagnosis of generalized anxiety disorder was added to the employee’s chart note when he saw Dr. Funk in October 2002.

In November 2002, Dr. Funk noted that the employee was experiencing anxiety due to having to drive a snowplow,  “he stays up at night watching the weather reports.  He cannot sleep because of fear of snow.  I think, at this point, we need to get him out of that job.”  The employee was given a work slip on November 18, 2002, which took him off operating heavy equipment.  The employee testified that he gave his work restrictions to his supervisor and was told that if he could not drive a snowplow, there would be no work for him.  The employee went off work around December 6, 2002, and did not return to work until around March 6, 2004.  The employee returned to his regular duties at that time and has continued to work for the employer in his job as a transportation generalist without restrictions.

In the interim, the employee used sick leave and his vacation time while he was off work.  He also continued to treat with Dr. Funk and was referred for psychological counseling.  The employee saw a psychiatrist, Dr. Shakeeb Hussain on January 21, 2003.  In his history notes Dr. Hussain stated,

In a report of September 29, 2005, Dr. Funk stated that the employee “developed severe phobia and anxiety disorder caused by the stresses of his job . . . .  Robert approximately four years ago developed a severe anxiety reaction while driving snowplow after two near accidents.”  Dr. Funk further stated that the anxiety disorder had created an increased in symptomology for his GERD and mitral prolapse conditions.

The employee’s claim petition, filed on November 18, 2005, was heard by Compensation Judge James Cannon on August 2 and 3, 2007.  In his findings and order of November 8, 2007, the compensation judge found, in relevant part, that the employee had established that his diagnosed mental stress had produced or substantially aggravated his physical conditions of  mitral valve prolapse and GERD.  The compensation judge also determined that the employee had not established legal causation in support of his claim and denied the employee’s petition.

Minnesota case law recognizes that work related mental stress resulting in physical conditions which are susceptible of discrete medical treatment may result in a compensable personal injury.  Johnson v. Paul’s Auto & Truck Sales, 409 N.W.2d 506, 40 W.C.D. 137 (Minn. 1987).  To establish compensability, the employee must present sufficient medical evidence to prove that the physical condition was the result of mental stress and must present evidence of a causal connection sufficient for a finding of legal causation.  Egeland v. City of Minneapolis, 344 N.W.2d 597, 36 W.C.D. 465 (Minn. 1984).  Subsequent case law has summarized these requirements as being the obligation of the employee to establish medical causation and legal causation.

In the present case, the compensation judge concluded that the employee had established medical causation.  That is to say, the compensation judge found that the employee’s mental stress or anxiety disorder had produced or aggravated that employee’s physical conditions of GERD and mitral prolapse disease.  The compensation judge determined, however, that the employee had failed to prove legal causation.  On appeal, the employee contends that the compensation judge erred in this determination.

To prove legal causation, the employee must produce evidence that stress was extreme or beyond the day-to-day stress experienced by all employees.  Courtney by Higdem v. City of Orono, 424 N.W.2d 295, 297, 40 W.C.D. 1117, 1120 (Minn. 1988).  The existence of stress in the workplace must be proven other than by means of the employee’s own testimony.  Egelund, 344 N.W.2d at 603, 36 W.C.D. at 474.  The job stress for the claimant must be compared to the job stress for all employees and not just the stress experienced by the claimant and co-workers.  Perdue v. Independent Sch. Dist. #625, slip op. W.C.C.A. (May 12, 1998).  Determining whether the employee has met his or her burden in proving such stress is a question of fact for the compensation judge which must be affirmed by this court if the determination is supported by substantial evidence in the record as a whole.  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 39 W.C.D. 235 (Minn. 1984).

The employee argues that the record shows that he provided substantial evidence to establish causation.  He contends, first of all, that in finding medical causation the compensation judge recognized that the job stress experienced by the employee was substantial; substantial enough to aggravate his physical condition.  According to the employee, this finding “bootstraps” to a finding of legal causation.  We disagree.

A determination of medical causation means only that the compensation judge has found that the employee established a causal connection between stress and the physical condition.  In his brief, the employee states that he was predisposed to become anxious when exposed to traumatic, noisy events. Such a predisposition, however, establishes only one individual’s reaction to stress. While this evidence may assist in establishing medical causation between the job stress and the diagnosed physical conditions, a reaction to stress based on a predisposition does nothing to answer the question in issue here of whether the stress is beyond the job stress experienced by all employees.  Contrary to the employee’s assertion in his brief, the questions of medical and legal causation are not “intermixed and overlapping.”

It was the employee’s argument at hearing that the three motor vehicle accidents in 1993 and 1996 precipitated his anxiety disorder and that his anxiety disorder was worsened by the stress of driving a snowplow in wintery conditions with its concomitant risk of additional accidents.  This anxiety disorder led to the aggravation of his physical condition.  The employee argues here that these motor vehicle accidents are objective evidence of extraordinary stress the employee had on the job.  The employee states that these types of events were unusual and were “loud, noisy and traumatic events.”  The employee further argues that the stressful nature of these accidents is demonstrated by their rarity.

The employee reported three motor vehicle accidents between November 1993 and December 2002 - a period of nine years.  There is no evidence as to whether 3 accidents in nine years is an unusually high number of accidents for DOT drivers or not.  More to the point, there is no evidence at all that the occurrence of these accidents could be considered a source of extraordinary stress or stress beyond the day-to-day stress experienced by all employees.  As the compensation judge noted, these were incidents with no personal injuries, which occurred at minimal speeds, and which resulted generally in little property damage.  The employee presented no evidence other than his own testimony to establish extraordinary stress.  It was only in the employee’s testimony that there was any evidence that these motor vehicle accidents were stressful or that the task of plowing snow was stressful.  There was no evidence that this reported stress was beyond the day-to-day stress experienced by all employees other than a statement by the employee that these incidents were not “normal.”  Egeland specifically held that an employee’s testimony alone is not sufficient to support legal causation.

We conclude substantial evidence supports the determination of the compensation judge that the employee failed to establish legal causation for his claims in this case.  The decision of the compensation judge is affirmed.