For an occupational health specialist, another question looms large: Is this problem caused by the patient's job? Often, the answer is simple and straightforward, but sometimes determining work-relatedness can be extremely difficult. Here are five things providers must know to make a determination. 

1) Know the circumstances. To understand the mechanism of injury, a detailed and accurate history of exactly what happened should be obtained.

• When and where did the incident occur? 
• What was the employee doing when she was hurt? 
• How much weight was she lifting, or with how much force was she pushing or pulling? 
• Ask the employee to demonstrate what position she was in, and what motions she was making when the injury occurred. 
• If there was a fall, how far did she fall? 
• How exactly did she land? 
• What happened immediately after the fall? 
• Was she able to continue working, or did she have to stop?

If the employee is reporting an occupational illness, such as repetitive motion, or a chemical-induced injury, similar detail is necessary.

• What exactly does he do, and for how long? 
• Has his job recently changed, in either intensity or type of task? 
• Was he exposed to any chemicals? 
• What did the employee report and when? 
• Were there any witnesses? 
• Did the employee appear to be injured? 
• Does the employee use personal protective equipment? 
• Does he use tools or operate machinery properly, and are these items in good working order? 
• How long has he worked for the company? 
• Are there any performance issues? 
• Has he had conflicts with co-workers or supervisors? 
• In case of an exposure, review MSD sheets for chemicals.

A complete and accurate history is crucial in all cases of alleged work injury, and full communication between the provider and the employer is essential. 

2) Know the job. While a written job description is helpful, an on-site visit by the provider is invaluable. Seeing the job being performed provides a more complete picture of whether an injury could result from such activities.

• What exactly is the employee's job? 
• What are the physical requirements, like lifting, pushing, or pulling? 
• What motions are involved, such as bending, kneeling, climbing or crawling? 
• What is the work environment -- indoors, outdoors or both? 
• What tools or machinery is used? 
• Is chemical exposure possible? 
• Has the job recently changed? 
• What hours are worked, including overtime?

3) Know the patient. The employee should complete a pain diagram to document exactly what body parts are involved and grade his level of pain.

• What makes it better and worse? 
• Is there numbness, weakness or any other symptoms? 
• What is he doing to treat it? 
• Has he already had medical treatment? 
• Is he taking medication? 
• Is he currently working, and can he do his regular job? 
• Has he had prior injuries or problems in the same areas or other areas? 
• Has he had physical therapy, injections or prior surgery? 
• Does he have arthritis or any medical illnesses? 
• Does he play sports, engage in hobbies or do any intensive physical activity outside work? 
• Does he have other jobs?

It can be helpful to ask the patient what he thinks is causing his problem. On the physical exam, look for swelling, bruising, deformity or any objective signs of an injury. Assess his range of motion and strength. Check circulatory and neurological function. Plain x-rays rarely aid in the diagnosis of a soft tissue injury, but they can reveal underlying arthritis or degenerative disc disease, which may be factors in determining causation. An MRI is often needed, particularly in cases of prolonged complaints, chronic problems or alleged injuries where evaluation has been delayed. Records of prior treatment should also be obtained, if possible. 

4) Know the literature.

• What has been published on this type of injury? 
• What is known about its causation? 
• Unfortunately, for many of the common problems we attribute to repetitive use, good scientific data on causation is thin and doesn’t have much practical value. One exception is carpal tunnel syndrome (CTS). For example, current research shows that keyboard work is not associated with a higher risk of CTS. The cause of most cases is unknown. But it is associated with middle age, family history, female gender, pregnancy, obesity, smoking, hypothyroidism, diabetes and both degenerative and rheumatoid arthritis.

5) Know the law. Employers always want to know if an injury is “work related,” but this is not a legal term and is often misunderstood. The proper concepts are causation and compensability. 

Causation is defined legally. Current Missouri law uses the term “prevailing cause,” which is defined as the occupation being the “primary factor in relation to all other factors, causing both the resulting medical condition and disability.” [Missouri Revised Statutes, Sec. 287.020 ¶ 3 (3)] This language applies to both occupational injuries and diseases (meaning repetitive use conditions, i.e. carpal tunnel syndrome).

Compensability is a term used to describe whether an injury or illness is covered by workers’ compensation benefits. Causation is a medical decision, made by the provider. 

Compensability is a legal/administrative decision made by the employer or his insurer. They are related, but not the same. Compensability is partly based on causation, but other factors are involved. It is very possible that an occupational activity could be the prevailing cause of an injury, yet it would not be eligible for treatment in the workers’ compensation venue. 

Employers should expect their occupational provider to know how causation is defined and to give an opinion on whether an employee’s injury fits this definition. This should be then brought to an insurer or TPA to determine if the case is compensable as a work injury. 

Causation is a very important and multi-faceted topic. BarnesCare providers are experienced and knowledgeable on causation and are always available to answer questions and discuss specific cases.

This article was prepared by Jerald Maslanko, MD, BarnesCare physician.