The Court of Appeals in the 3rd District has issued a blockbuster opinion on apportionment in City of Jackson v WCAB (Rice) regarding the requirements for substantial medical evidence in worker’ compensation cases. 

Jake Jacobsmeyer

In reversing the Workers' Compensation Appeals Board, the court laid out its analysis of why a qualified medical evaluator's apportionment to genetic factors was well-supported and legally sufficient.

The applicant in this case was a relatively young, 29-year-old police officer who developed cervical spine pain resulting in the need for surgery. He was evaluated by QME Sloane Blair on multiple occasions. In his final evaluation, Dr. Blair apportioned the applicant’s disability to multiple factors, including 17% each to his employment with the city, prior employment and to personal activities. The remaining 49% was apportioned to the applicant's personal history, including “genetic issues.”

In response to a request for supplemental report from the applicant attorney, Dr. Blair further clarified the basis for her opinion:

“… 'to a reasonable degree of medical probability that genetics has played a role in Mr. Rice’s injury,' despite the fact that there is no way to test for genetic factors. Citing to the referenced medical studies, Dr. Blair stated that one of them said 'heritability was ... 73% in the cervical spine. ... [S]moking, age and work are only a small percentage of disc disease and most of it is familial.' Another source cited the role of heritability in disc degeneration as 75%, and the other stated it was 73%. Dr. Blair cited a fourth article that claimed, ' "[t]win studies demonstrate that degeneration in adults may be explained up to 75% by genes alone."' The same study found environmental factors to contribute little or not at all.  Dr. Blair stated that while these studies supported an apportionment of 75% to personal history, she decided to err on the side of the patient in case there was some unknown 'inherent weakness' in the study, and decided that 49% was the 'lowest level that could reasonably be stated.'

The workers' compensation judge accepted Dr. Blair’s apportionment to genetic factors but rejected the other apportionment awarding disability based on 51% industrial causation. On reconsideration, the WCAB reversed, asserting Dr. Blair’s apportionment to genetic factors resulted in an allocation of disability to impermissible immutable factors and not to “specific identifiable factors,” and was therefore not substantial evidence.

The 3rd District took issue with the WCAB’s entire analysis of this apportionment issue. Noting the specific intent of SB 899 to allow apportionment to “other factors,” the court went through multiple WCAB and appellate court decisions on apportionment and could find little to distinguish apportionment on the basis of degenerative joint disease, asymptomatic prior conditions, etc. 

The court specifically rejected the WCAB’s reference to “impermissible immutable factors,”  commenting as follows:

“… Precluding apportionment based on 'impermissible immutable factors' would preclude apportionment based on the very factors that the legislation now permits, i.e., apportionment based on pathology and asymptomatic prior conditions for which the worker has an inherited predisposition."

The court pointed to several instances where medical evidence relied on apportionment to genetic dispositions to develop medical conditions, citing the Kos v. WCAB, Escobedo and Acme Steel cases, and further noting:

"... We perceive no relevant distinction between allowing apportionment based on a pre-existing congenital or pathological condition and allowing apportionment based on a pre-existing degenerative condition caused by heredity or genetics.”

The court also rejected the WCAB’s analysis that Dr. Blair’s reliance on the applicant’s genetic makeup resulted in apportionment to the causation of injury rather than the causation of disability. The court pointed out the cause of the injury was repetitive motion, not genetics. Rather, Dr. Blair commented that the applicant’s disability was caused by a combination of factors including a significant contribution from his genetic makeup.

The court was also not put off by the QME’s reliance on medical literature to support her conclusion rather than on a specific history from the applicant of his genetic makeup or background. As noted by the court, the doctor’s conclusion was supported by significant, unrebutted medical literature that found degenerative disc disease was influenced significantly by genetic factors and only minimally to environmental factors such as work activity. 

The court points out that the research relied upon by Dr. Blair supported the conclusion that up to 75% of all degenerative disc disease was related to genetics, and the issue was not whether one could prove that the genetic factor existed; the existence of significant DDD established the genetic factor as present.

“Dr. Blair’s reports meet all of the requirements of Escobedo. Dr. Blair expressly stated that confidence in her opinion was predicated on reasonable degree of medical probability. Dr. Blair gave the reasoning behind her opinion — the published medical studies — and even named the studies and the pages relied upon. Her opinion disclosed familiarity with the concept of apportionment. Labor Code section 4663 states that apportionment is based on causation, and that '[a] physician shall make an apportionment determination by finding what approximate percentage of the permanent disability was caused by the direct result of injury arising out of and occurring in the course of employment, and what approximate percentage of the permanent disability was caused by other factors ...'  (Lab. Code, § 4663, subd. (c).)”

The case was remanded to the WCAB to issue an opinion based upon the QME’s conclusions.

Comments and conclusions

Assuming this decision holds up (it is certainly likely to be appealed further), it dramatically reinforces the rules on apportionment to any relevant factors that a physician can identify with reasonable medical probability. 

There are some fairly unique circumstances in this case that may have played a role in the ultimate outcome. First the applicant was relatively young to have significant DDD, only 29. That fact probably tipped Dr. Blair off that there was something about the condition that could not be attributed to environmental factors, including work.

Second, the length of employment as a peace office was not lengthy, as the applicant had worked fewer than five years in a full-time capacity. There had not been a lot of time to attribute causation to work activity.

There is also fairly strong support in the medical literature that DDD is not really activity-related. Other than studies that suggest whole-body vibration is a significant factor, there is little to suggest that bending, lifting and stooping, without significant trauma, plays any role in the development of disc disease — much like carpal tunnel syndrome, where the medical literature overwhelming fails to demonstrate a relationship between computer usage and the disease process, yet we still routinely get compensable reports without any real support in the medical literature — spine pain is constantly related to even relatively benign work activities as a matter of course. 

Clearly, defense attorneys need to start appearing at doctor depositions armed with the literature cited by Dr. Blair and challenge physicians to provide a basis for their unapportioned or minimally apportionment spine cumulative trauma claims, especially in younger individuals.

This decision may have even broader applications in non-orthopedic cases. We have a wealth of literature about causation of various internal medicine conditions and even psychiatric conditions attributable to genetic, historical and environmental factors that now can more carefully be considered to support apportionment where previously the WCAB had been rejecting such opinions. The issue of whether there can be apportionment to genetic factors or predispositions would appear to be resolved in the affirmative in this case.

Richard M. "Jake" Jacobsmeyer is a founding partner of the Shaw, Jacobsmeyer, Crain and Claffey workers' compensation defense law firm, based in Oakland.