- Board Directives and Guidelines (apportionment)
- Permanent impairment {NEL} (degree of impairment) (back)
- Permanent impairment {NEL} (rating schedule) (AMA Guides)
- Apportionment (non-economic loss) (preexisting conditions)
The worker suffered a low back injury in 2011. The Board granted a 10% NEL award but reduced the award to 3% due to a pre-existing condition. The worker appealed a decision of the Appeals Resolution Officer regarding the quantum of the NEL award for sensory deficit symptoms and regarding the reduction of the award.
The process for rating sensory deficit in the leg is as follows: 1) determine the grade of nerve root impairment under Table 10a of the AMA Guides; 2) convert that rating into a percentage impairment of the lower extremity as per the instruction in Table 10b and using Table 59; 3) combine all lower extremity percentage impairments; 4) convert the total combined lower extremity impairments to a percentage impairment of the whole person.The Board found that the worker had a Grade 2 impairment under Table 10a for her nerve root impairments at both L5 and S1. The Vice-Chair noted that Grades 2, 3 and 4 all involve decreased sensation with or without pain. The differences in the ratings hinge on the degree of interference with activity. The Vice-Chair interpreted the reference to activity to mean activity generally in the sense that it broadly limits function; it is not a reference to specific sports, hobbies or pastimes. For Grade 2 the decreased sensation is forgotten during activity, for Grade 3 the decreased sensation interferes with activity and for Grade 4 the decreased sensation may prevent activity.The Vice-Chair was of the view that, when rating sensory deficit under Table 10, the reference to interference with activity must be understood to mean that the nerve deficit alone prevents or may prevent activity. Otherwise, there is potential overlap with the rating impairment for the spine itself.The Vice-Chair found that the worker's nerve impairments came within Grade 3, which has a range of 26% to 60%. The Vice-Chair found that the choice within the range should depend on the severity. In this case, the Vice-Chair rated the worker at 50%.The Vice-Chair then followed the rest of the rating process and found that, although there was an increase in the rating for the lower extremity, the resulting whole person rating was still 10% when combined with the rating for the spine.The new Board policy, dated November 3, 2014, on determining the degree of permanent impairment, was applicable to this appeal. According to the policy, to factor out a pre-existing condition, it must be established that it is contributing to the degree of impairment to the same area of the body as the work-related impairment. To establish this, the evidence must show that the pre-existing condition, on its own, would result in an impairment rating. The pre-existing condition does not need to have produced periods of impairment requiring health care or have cause a disruption in employment in order to factor out its rating.The Vice-Chair considered potential conflict between the requirement that the pre-existing condition would result in an impairment rating and the lack of need for periods of impairment requiring health care or disruption in employment. The Vice-Chair found no inherent conflict. There may be circumstances where there has been no health care or disruption of employment, yet the worker still had a pre-existing condition. In order to be factored out, such a pre-existing condition would have had to be symptomatic, even though there was an absence of health care or disruption of employment. Health care and lost time are both evidence of a symptomatic condition but there may also be other evidence of a symptomatic condition.In this case, the Vice-Chair found that the worker did not have a symptomatic pre-existing condition. Accordingly, she was entitled to the 10% NEL award without reduction.The appeal was allowed in part.