By J. Mark Melhorn, MD

Causation is an issue in work-related injuries

Orthopaedic surgeons frequently see patients with work-related musculoskeletal injuries. Many, however, are unfamiliar with the legal, administrative, ethical, and insurance requirements involved when treating workers’ compensation patients.

In addition to the traditional medical history, physical examination, diagnosis, and treatment requirements, the physician is often asked to provide an opinion as to the cause of the injury. In other words: Did the job cause the injury or illness for which the patient (injured worker) is being seen?

The answer to the causation question may be straightforward or difficult. When a laceration, broken bone, or amputation with an obvious bloody wound results from trauma that was directly observed by coworkers, the answer is obviously yes, the injury occurred on the job. But what about the nontraumatic, unobserved, and gradually occurring-over-time injury, often labeled as the “I hurt, and I hurt in the workplace” injury?

That question is a little more difficult to answer and requires an understanding of why causation is so important. Causation determines who is going to pay for the injured party’s medical care and any subsequent settlement that may be granted for the patient’s residual impairment.

Workers’ compensation plans
Before workers’ compensation insurance was established, the injured worker had to sue his or her employer for negligence, a difficult and costly process that rarely resulted in a favorable decision for the employee. In the 1880s, in an effort to provide social balance, workers’ compensation insurance was established as a no-fault approach. Employees gave up their right to sue employers for negligence in exchange for a guarantee of wage replacement and medical benefits “if the injury occurred out of or in the due course of employment.”

Workers’ compensation plans differ between jurisdictions. There are five federal programs, 50 state programs (with multiple options within each state), and programs within U.S. territories. These programs provide for weekly payments in place of wages (a form of disability insurance), compensation for economic loss (past and future—settlement), reimbursement or payment of medical and like expenses (a form of health insurance), and/or benefits payable to the dependents of workers killed during employment (a form of life insurance). By accepting these benefits, the employee gives up the right to sue for general damages for pain and suffering and punitive damages for employer negligence.

The threshold requirement is the standard that defines whether or not an employee is eligible for payments under workers’ compensation laws. It is defined by each jurisdiction’s legislative body and was originally administered by each jurisdiction’s legal body. In most states, however, special administrative agencies now have jurisdiction over workers’ compensation disputes.

Within these agencies, disputes are usually handled informally by administrative law judges (ALJs). ALJs make the final decision on the threshold question of “if the injury occurred out of or in the due course of employment.” However, the physician needs to know which jurisdiction applies and which threshold question is being asked.

Redefining the threshold
Although most states define threshold as “more probable than not,” some state legislatures have recently adopted other measures.

For example, Kansas previously considered the patient’s injury or condition to be work compensable “if the job activities contributed one iota.” Therefore, almost any condition became work compensable. But in May of this year, Kansas passed House Bill No. 2134, An Act Concerning Workers Compensation, which includes a “Prevailing Factor Test.” Under this test, the employee’s work must be the “prevailing factor” for the injury to be considered work-compensable. If work is not the prevailing factor, the injury is not compensable.

This standard may provide employers with a defense against pre-existing degenerative conditions not caused by work. In other words, employees will no longer have a compensable claim for an aggravation, acceleration, or intensification of a pre-existing condition. Unfortunately, the Kansas legislature did not define prevailing factor, nor did it reference the Missouri workers’ compensation law, which could then have been used as case law to assist in the definition.

Passed into law on Aug. 28, 2010, the Missouri Workers’ Compensation Law requires that the work injury must be the prevailing factor in comparison to any other possible factor in causing the level of disability and medical condition for the injury or condition to be compensable.

A similar definition was adopted in Oklahoma in May 2011. Oklahoma’s workers’ compensation bill not only includes a major cause provision (which has yet to be defined by case law but will probably be “contributes more than half”), but also a requirement that objective medical evidence be determined by the Daubert criteria (Fed Rule of Evidence 702, expert testimony) for the opinion of major cause.

Thresholds have been further complicated by the concepts of aggravation, exacerbation, and apportionment. The next few years will undoubtedly see increased litigation and costs, as well as increased levels of frustration for physicians treating these cases—especially if the physician is unfamiliar with these legal requirements.

To address these issues, the AAOS is offering its 13th annual “Occupational Orthopaedics & Workers’ Compensation Course: A Multidisciplinary Perspective” continuing medical education (CME) course, Nov. 4–6, 2011, in Las Vegas. The course is designed to provide fresh perspectives on treatment options, patient care management, and strategies for handling the nonmedical issues associated with workers’ compensation.

For more information, visit www.aaos.org/courses

J. Mark Melhorn, MD, is the course director for “AAOS Occupational Orthopaedics & Workers’ Compensation Course: A Multidisciplinary Perspective.”