In addition to the testimony of Dr. Poetz, who opined that employee is permanently and totally disabled owing to a combination of her preexisting conditions, the primary injury, and a subsequent August 2005 left shoulder injury, employee presented the expert vocational testimony of Sherry Browning, who agreed that employee is unemployable in the open labor market. Ms. Browning identified problems with the left shoulder, low back, and left knee as contributing to employee's permanent and total disability. Ms. Browning opined that if employee had a need to lie down during the day referable to the primary low back injury, this would not render employee permanently and totally disabled due to the low back alone, and reiterated her belief that employee is permanently and totally disabled due to a combination of the low back, left knee, and left shoulder conditions.
It appears to us that employee's expert opinion evidence as to the issue of permanent total disability is not particularly relevant, in that both Dr. Poetz and Ms. Browning identify a subsequent left shoulder injury and surgery as contributing to employee's inability to compete in the open labor market. The August 2005 left shoulder injury is not before us. Rather, we are concerned with the question of employee's medical condition when she reached maximum medical improvement on June 22, 2005, and whether the primary injury considered alone or in combination with employee's disability preexisting December 15, 2003, renders her permanently and totally disabled.
The Second Injury Fund presented the expert vocational testimony of James England, who opined that employee is permanently and totally disabled as a result of the primary injury if one assumes employee has to lie down during the day and doesn't get adequate sleep owing to her low back pain. Mr. England alternatively opined that employee is not permanently and totally disabled and that she could handle at least sedentary work. We do not find Mr. England's testimony as supportive of a finding that employee is permanently and totally disabled as a result of the work injury considered in isolation, because we are not persuaded that employee has a need to lie down to relieve pain that is solely due to the work injury. We note that employee, at the hearing before the administrative law judge, merely testified that she began to lie down for pain relief after the primary injury, and did not specifically identify the effects of the primary injury as the reason she needs to lie down. Given employee's preexisting pain condition referable to the left knee, and the aforementioned subsequent August 2005 left shoulder injury, and in light of employee's failure to provide specific credible testimony to resolve this issue, we decline to make any finding that employee has a need to lie down referable to the primary injury considered in isolation, or due to any combination of conditions.
In light of the foregoing considerations, we are not persuaded that as of June 22, 2005, employee was rendered permanently and totally disabled by the primary injury, considered alone and in isolation. Rather, we find that the primary injury caused employee to suffer an overall 42.5% permanent partial disability of the body as a whole referable to her low back and tailbone injuries. Nor are we persuaded that as of June 22, 2005, employee was
rendered permanently and totally disabled owing to a combination of the effects of the primary injury and her preexisting disability referable to the left knee.
We do, however, find persuasive Dr. Poetz's testimony to the extent he identified a synergistic interaction between employee's preexisting disabling condition of the left knee and employee's disability resulting from the primary injury. We find that employee's preexisting left knee disability combines with the effects of the primary injury in such a way as to produce more disability than the simple sum of disability referable to these conditions.