Understanding the application of prior disability against subsequent injury can be challenging. Labor Code section 4751provides for employees with preexisting disabilities the chance to become employed without the new employer becoming responsible for significant exposures should the employee sustain a subsequent industrial injury. (Ferguson v. IAC (1958) 50 Cal. 2d 469.)

One challenge is determining the correct method of determining the proper math of combining the employee’s overall disability. Do we use the Combined Values Chart or the older Multiple Disabilities Table? That question was recently addressed in Kudelka v. City of Costa Mesa, 2019 Cal. Wrk. Comp. P.D. LEXIS 436. The panel found that the proper method would be to add the prior and subsequent disabilities.

In Kudelka, applicant had a prior heart injury resulting in an award of 36% permanent disability. Several years later he sustained a second injury to multiple body parts, including the heart, resulting in 76% permanent disability after apportionment. This did not include apportionment to the prior heart award as it was considered a separate and distinct injury.

Applicant filed an application for benefits from the Subsequent Injury Benefit Trust Fund (SIBTF). He claimed that his prior award of 36% permanent disability for the heart should be added to his subsequent non-overlapping award of 76% to produce permanent and total disability. SIBTF argued the prior and subsequent disabilities should be combined by use of the CVC to produce permanent disability of 85%. The trial judge confirmed applicant had finding that satisfied the requirements of Labor Code section 4751 and the WCJ added the prior and subsequent disabilities and issued an award of 100% permanent disability with SIBTF liability.

SIBTF sought reconsideration on the basis that applicant’s prior disability was not labor disabling as required by Labor Code section 4751 and that the award of 100% permanent disability was incorrect because the WCJ did not use the CVC to calculate overall disability.

The decision breaks down the elements of Labor Code section 4751. Applicant’s prior heart injury is a labor-disabling impairment because he time lost from work, there was a need for ongoing treatment, applicant was symptomatic at the time of his subsequent injury, there was no evidence of rehabilitation and applicant received an award of permanent partial disability. The descion confirms that prior labor disablement does not mean loss of earnings alone. (Smith v. IAC (1955) 44 Cal. 2d 364.)

However, more significantly, is the conclusion that overall disability is determined by adding the prior non-overlapping disability to the subsequent disability rather than combining. This decision is taken based on the findings of Bookout v. WCAB, (1976) 62 Cal. App. 3d 214, as well as the language in both the CVC and the MDT. In Bookout, applicant sustained an industrial injury to his back that caused a limitation to semi sedentary work (60% standard). He had a prior non-industrial heart disability that caused a preclusion from heavy work (30% standard) as well as a preclusion from excessive emotional stress (12% standard). The Court of Appeal determined applicant was erroneously denied SIBTF benefits under Labor Code section 4751 because the rater apportioned the 34.5% nonindustrial heart disability from the subsequent industrial back disability of 65%, instead of using the total disability for the subsequent injury, standing alone and without regard to or adjustment for the age and occupation of the employee, as required by Labor Code section 4751. Thus, for purposes of SIBTF liability, the permanent disability attributable to the subsequent industrial back injury was 60%, which is greater than the minimum requirement of 35% in Labor Code section 4751.

The Court of Appeal then noted that the WCJ had instructed the rater to include the preexisting with the subsequent disabilities for purposes of calculating overall disability. The rating specialist combined the disabilities by use of the MDT. The preclusion from heavy work attributable to the preexisting nonindustrial heart disability was found to be subsumed by and overlapped the permanent disability attributable to the subsequent industrial back disability that was based on a limitation to semi-sedentary work. The preclusion from excess emotional stress caused by the preexisting heart disability was found to have caused 12% permanent disability. Based on the WCJ’s instructions, the rater combined the 12% non-overlapping heart disability with the 65% permanent disability attributable to the subsequent back injury by use of the MDT, resulting in 70.5% permanent disability. The Court of Appeal rejected use of the MDT and held that the 12% non-overlapping heart disability should have been added to the 65% instead, resulting in 77% overall disability.

Also, while acknowledging that Labor Code section 4751 uses the words combination and combined in reference to the prior and subsequent disabilities, Kudelka finds that these words do not denote a specific method of how to combine disabilities. Addition is one method of combining and use of the CVC/MDT is another method of combining. Kudelka finds the language within the 2005 and 1997 PDRS to suggest that the CVC/MDT are intended to rate disabilities arising from a single injury only.

The Kudelka decision may not be the final ruling on the proper method to determine overall disability under Labor Code section 4751 especially since the SIBTF refularly defends against liability. However be prepared for these arguments.