Idiopathic Defense

workers’ compensation lawyer


You were hurt at work and the workers compensation insurance company is denying your benefits claiming that you suffered an IDIOPATHIC injury.  What does this mean?

In Wisconsin, the workers compensation system under Chapter 102 of the Wisconsin Statutes provides benefits such as lost time, medical treatment expense, medical mileage reimbursement, and permanent disability to Wisconsin workers who are injured on the job.  This system is considered a no-fault system, which means that the injured worker does not need to prove that anyone was at fault for their injuries to receive benefits.  Nevertheless, workers compensation insurance companies come up with all kinds of reasons to deny a claim and one of the more common reasons is to claim that the injury is “idiopathic.”


Webster Dictionary defines Idiopathic as “arising spontaneously” or “from an unknown cause.”

Some examples of idiopathic injuries are if an employee faints, suffers a seizure or blacks out due to a personal condition, the resulting injury could be an idiopathic injury.  For instance, if an employee’s leg gives out while normally walking or standing at work this might result in an idiopathic injury.  Also, if an employee slips and falls while on the job, where there is no object, or residue on the floor to cause the slip, the employee might have sustained an idiopathic injury, which would not be compensable.

While it may be fun to play with this word, and name call it right back on the IDIOT-PATHETIC insurance adjuster who is denying your workers compensation benefits, but in serious, this office is seeing this defense being used more and more against injured Wisconsin workers in the denial of workers compensation benefits.

Perhaps, a better term for this defense is to call it an “unexplained injury” which arises from purely a personal cause, like a disease, physical disability, or a condition personal to the injured worker.  To recover workers’ compensation benefits, the employment must place the employee in a position that somehow increases the dangerous effects of a fall.    


In the Wisconsin workers compensation setting, idiopathic or unexplained injury cannot be due to a force completely personal to the employee.  The easiest example of an idiopathic injury is a heart attack suffered at work.  Only under very special circumstances of extreme stress endured on the job, would a heart attack suffered at work be considered a compensable work injury because heart attacks are caused by heart disease, not work events or exposure.

Many Wisconsin injured workers ask how it can be that a fall on-the-job, on their employer’s premises, causing injury excuse the employer’s workers compensation insurance carrier from the responsibility of covering medical treatment and lost time?  Such a premise just feels wrong and unfair.  Unfortunately, Wisconsin is in the minority of states that does not allow compensation for unexplained or idiopathic falls.

In Wisconsin, slipping on a clean, unobstructed cement/hard floor will not be considered a special hazard of employment and will be deemed idiopathic. However, in Attorney Lisa Pierobon Mays’ experience, slip and fall injuries are always more involved than that.  Hazards exist that can render what appears idiopathic explainable, such as elevators, stairs, ladders, scaffolds, sharp edges, corners, and water to name a few.  Sometimes injured workers do not know or remember what caused their fall and resulting injury because falls happen so fast.

Claims involving potential idiopathic injuries are fact intensive and fact specific, so it is very important for the injured worker to reflect on and timely investigate their fall before documenting or completing an Incident Report of the injury requested by their employer.  The workers compensation insurance carrier will use a statement of “I do not know what happened” against the injured worker as a basis to claim Idiopathic injury to deny workers compensation benefits.


In Attorney Lisa Pierobon Mays’ experience, a denial of benefits under the idiopathic defense can be overcome when the Wisconsin worker sustains an idiopathic injury that was aggravated or accelerated due to work-related activities. Examples are:

  • Slip and Fall Due to Seizure: An employee with epilepsy experiences a seizure while on a ladder at work and falls, causing injury. While the seizure may be idiopathic, the fall and resulting injury were related to the work environment and activities (being on the employer’s ladder), so the injury might be covered.
  • Injury During Diabetic Event: A diabetic employee experiences a drop in blood sugar, causing them to faint. In the process, they hit their head on a machine, causing a severe head injury. The injury from the fall could be eligible for workers’ compensation (hitting the head on the employer’s machine), even though the fainting spell was due to a personal health condition.
  • Injury Exacerbated by Work: An employee with a pre-existing back condition injures their back further while lifting heavy equipment at work. Even though the initial back condition is idiopathic, the worsening of the injury due to work activities (lifting the employer’s heavy equipment) could make the case eligible for workers’ compensation.

As you can see every injury is fact specific so after a fall that results in an injury, the injured employee should try to document the fall and consider their recollection carefully.  Steps to take are:

*Build a timeline and consider your actions and activities before the injury occurred,

*Revisit the scene, take pictures, request surveillance footage,

*Speak to witnesses,

*Retrace your steps to try and determine why and how the fall occurred are all ways to combat a defense of idiopathic injury.

In doing so, the injured worker might learn the reason for their fall.  For instance, slippery surfaces caused by spills or leaks, footwear required by the employer, objects on the floor or in the way, fast walking due to rushed work effort or response to an emergency, along with uneven surfaces are often the reason for the fall.  Workers without preexisting disabilities generally do not just fall on a clean, dry, smooth surface.  There is always more to the story that needs to be flushed out when explaining the circumstances of the injury to the employer and their workers compensation insurance carrier.   Moreover, the details of the fall need to be consistent, especially when describing it to medical providers because this is another source of credible documentation.


Lastly, call Attorney Lisa Pierobon Mays so that she can explore the facts and circumstances with you to give further suggestions.  Mays Law Office offers free consultations to all Wisconsin injured workers.  Mays Law Office has the coveted 5 Star Google rating from their former clients proving that they get results.