The employee appeals from the compensation judge’s determination that her right ankle fracture did not arise out of her employment.  We affirm.

The employee has been employed as a registered nurse at United Hospital [the employer]^[1] since 1993.  On work days, she would typically arrive at the hospital’s Gold Parking Ramp by about 6:15 a.m.  From the ramp, she would walk briskly through a skyway to the Heart Hospital and then into United Hospital itself, the site of her nursing station.  The employee testified that her walk from the ramp to her station took 10 to 15 minutes and that she usually arrived at her station about half an hour prior to the start of her 7:00 a.m. shift, using the extra time to familiarize herself with the particular patients and duties she would be dealing with that day.  Because she was on her feet for most of her shift, the employee wore athletic shoes, for comfort, at work.  She testified that she did not use those particular shoes for anything other than her job at the hospital, but the shoes were not part of a uniform or required by the employer.

On the morning of December 19, 2006, the employee arrived at her parking ramp at about 6:15 a.m., as usual.  Just after passing through a door between the concrete ramp and the carpeted skyway, the employee fell, severely twisting her right ankle.  She made it to her station but called her supervisor to report the injury, and the supervisor took her to the emergency room.  X-rays taken at that time disclosed a nondisplaced fracture of the distal fibula and lateral malleolus.

Many records generated around the time of the accident indicate that the employee fell after catching the toe of her athletic shoe on the carpet in the skyway.  For example, an Employee Incident/Safety Event report indicates that the employee

The matter came on for hearing on March 14, 2008, for resolution of the employee’s claim for benefits related to her ankle injury.  The self-insured employer admitted that the injury had occurred in the course of the employee’s employment, “in the sense that it was an ingress to the employer’s facility”; the sole issue was whether the injury arose out of that employment.  The employee’s theory of the case was that, while walking from the smooth concrete of the parking ramp onto the carpeted skyway floor, the employee caught the toe of her athletic shoe on the carpet, causing her to twist her ankle as she fell, resulting in the fracture.  The employer contended, in contrast, that the mechanism of injury was unknown and that, in any event, the flat, smooth carpet of the skyway floor did not constitute an employment-related hazard, meaning that the employee fell for reasons having nothing to do with her job.  Evidence submitted at hearing included records containing descriptions of the incident at issue, a portion of the employee’s deposition testimony, and the athletic shoes that the employee had been wearing at the time of her injury.

In a decision issued on May 14, 2008, the compensation judge concluded that the employee’s December 19, 2006, injury did not arise out of her employment.  The employee appeals.

 On appeal, the Workers’ Compensation Court of Appeals must determine whether “the findings of fact and order [are] clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.”  Minn. Stat. § 176.421, subd. 1 (2008).  Substantial evidence supports the findings if, in the context of the entire record, “they are supported by evidence that a reasonable mind might accept as adequate.”  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 59, 37 W.C.D. 235, 239 (Minn. 1984).  Where evidence conflicts or more than one inference may reasonably be drawn from the evidence, the findings are to be affirmed.  Id. at 60, 37 W.C.D. at 240. Similarly, findings of fact should not be disturbed, even though the reviewing court might disagree with them, “unless they are clearly erroneous in the sense that they are manifestly contrary to the weight of evidence or not reasonably supported by the evidence as a whole.”  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).

Pursuant to Minn. Stat. § 176.021, subd. 1, employers are liable to pay compensation “in every case of personal injury. . . arising out of and in the course of employment without regard to the question of negligence.”

In the present case, the employee’s injury occurred as she was walking from her parking ramp to her work station prior to beginning her shift, and the employer concedes that the “in the course of” requirement was met.  See Starrett v. Pier Foundry, 488 N.W.2d 273, 47 W.C.D. 176 (Minn. 1992); Merrill v. J.C.Penney Co., 256 N.W.2d 518, 30 W.C.D. 278 (Minn. 1977) (parking lots owned or maintained by the employer for employees are considered part of the work “premises,” and travel between the employer’s parking lot and the main premises is considered to arise out of and in the course of the employment); and Satack v. State, Dep’t of Public Safety, 275 N.W.2d 556, 557 n.1, 31 W.C.D. 260, 261 n.1. (Minn. 1978); Starrett, 488 N.W.2d 273, 47 W.C.D. 176 (Minn. 1992) (an employee is covered for a reasonable period beyond actual work hours).  The sole issue before the compensation judge was whether the employee’s injury arose out of her employment.

In his decision, the compensation judge concluded that “the cause and/or mechanism of the fall on December 19, 2006, is unknown,” explaining in his memorandum as follows:

Given the employee’s deposition testimony, it was not unreasonable for the compensation judge to have concluded that the employee did not establish the mechanism of her injury.  As such, the employee did not establish that the “injury was caused by an increased risk to which the claimant, as distinct from the general public, was subjected by [her] employment.”^[2]  Bohlin v. St. Louis County/Nopeming Nursing Home, 61 W.C.D. 69, 72 (W.C.C.A. 2000), quoting 1 A. Larson and L.K. Larson, Workers’ Compensation Law § 3.00 (1999); see also Kirchner v. County of Anoka, 339 N.W.2d 908, 911, 36 W.C.D. 335, 338 (Minn. 1983) (the “arising out of” standard for compensability requires “a showing of some hazard that increases the employee’s exposure to injury beyond that of the general public”).

Other factors may have influenced the judge’s ultimate decision on liability here.  The incident occurred on a level, flat, smooth, carpeted surface, and there is no allegation either that any foreign object contributed to the injury or that there was any defect in the carpet itself.  That is, it would be difficult to characterize the skyway carpet, under these circumstances, as constituting any kind of “hazard” connected to the employee’s employment.  And, while the employee may have been injured on the employer’s premises, the accident occurred 45 minutes before her shift was to begin and a 15-minute walk away from her work station.  She was not performing any actual work activities at the time.^[3]  Viewed this way, both the “arising out of” and the “in the course of” requirements for compensability can be characterized as weak,^[4] whether or not the employee caught  her toe on the carpet, as claimed.  See Cauwels v. Schott’s, Inc., 61 W.C.D. 285, 290 (W.C.C.A. 2001); Polz v. Jackson County Sheriff’s Dep’t, slip op (W.C.C.A. Sept. 29, 2003) (if both the “arising out of” and the “in the course of”elements are weak, the necessary minimum connection to the employment will not be found).

Whether an injury arises out of and in the course of an employee’s employment is generally a question of fact for the compensation judge.  See Schreier v. Bruning Constr., 61 W.C.D. 507 (W.C.C.A. 2001).  No comprehensive definition can be fashioned to fit all cases; to a great extent, each case stands on its own facts.  See Gibberd, 424 N.W.2d 776, 780, 40 W.C.D. 1040, 1047 (Minn. 1988).  While we acknowledge that this case may fall close to the line, we cannot conclude, under these particular circumstances, that the compensation judge erred in denying the employee’s claim.  We therefore affirm his decision.

I respectfully dissent from the majority’s decision in this case.  I would reverse the compensation judge and hold that the employee’s injury arose out of her employment as a matter of law.

This case illustrates the limitations of the increased risk doctrine. The employee loses because she was not able to identify a precise reason for falling and because she could not connect the fall to a defect in the carpeting.  The employee had to prove that her fall was the result of a stumble, not a misstep.  Even then, she would have established “increased risk” only if there had been a wrinkle in the carpet.  No wrinkle apparently means no risk.  In effect, the workers’ compensation law has been transformed in this case from a no-fault system for injuries on the job into one in which an employee must prove negligence on the part of the employer and must also avoid a finding of contributory negligence.

The purpose of “arising out of” and “in the course of” requirement in the statute is to assure that the claimed injury has sufficient causal connection to the employment to impose liability on the employer.  The “arising out of” element establishes that the injury is related to employment risk rather than to personal risk.  In the instance of a worker who catches her hand in a punch press and who loses a couple of fingers, the connection to employment risk is obvious.  Similarly, if an employee has a heart attack while on the job, but the risk factors for that occurrence are all personal, no employment connection exists.

The problem arises in cases such as this where neither employment risk or personal risk can be shown.  The phrase “idiopathic injury” is sometimes used for such a case.^[5]  An idiopathic injury may also be referred to as a “neutral-risk case,” one in which “the cause itself, or the character of the cause is simply unknown.”  1 A.Larson and L.K. Larson Workers’ Compensation Law, Sec. 4.04 (2008).  The treatise goes on to point out that while past cases have tended to deny compensability, “more recently, however, some courts have reasoned in the following vein: either the employer or employee must bear the loss; to show connection with the employment there is at least the fact that the injury occurred while the employee was working; to show connection with the employee personally there is nothing; therefore, although the work connection is slender, it is at least stronger than any connection with the claimant’s personal life.”

By definition, if an unexplained injury occurs, increased risk cannot be shown.  If increased risk related to the employment can be shown, the injury would no longer be unexplained.  See Khani v. Mesaba Aviation, Inc., slip op (W.C.C.A. May 21, 2002).  To require that increased risk must be found in every case is to hold as a matter of law that an unexplained injury is never compensable.  I believe the better rule of law in the situation of an idiopathic or unexplained injury on the job, is to find the injury compensable.  To be plain, in the instance of an unexplained injury on the job, I would adopt the positional risk doctrine.

I would award benefits to the employee.