The employee appeals from the compensation judge’s denial of his claim for permanent partial disability benefits from Soil Testing Service of Minnesota and its insurer.  DCI, Inc., and its insurer cross-appeal from the judge’s refusal to equitably apportion liability for wage loss and medical expense benefits.  We reverse the compensation judge’s decision on both issues.

For purposes of this appeal, it is undisputed that the employee sustained a work-related injury to his low back on February 5, 1981, while employed by Soil Testing Service of Minnesota.  He subsequently underwent a laminectomy at L4-5 as a result of the injury, and Soil Testing and its insurer ultimately paid benefits for a 15% permanent partial disability of the back.  The employee did relatively well after surgery, performing heavy labor until he sustained two work-related lifting injuries,^[2] in Texas, while employed by a Texas employer, in 1991.  Thereafter, the employee underwent additional low back surgeries, one of which included a fusion at L4-5 and L5-S1, in the fall of 1991, early 1993, the fall of 1993, and the spring of 1994.  The employee was at one point rated by Texas doctors as having a 14% whole body impairment after the Texas injuries, but the record does not establish whether he received Texas benefits for permanent impairment.  The employee then sustained a second Minnesota work injury, on October 4, 2000, while performing heavy labor for DCI, Inc.  Following this injury, the employee underwent two more surgical procedures, including another fusion at L4-5.

The matter initially came on for hearing before the compensation judge in December of 2003.  Issues included the nature and extent of the employee’s two Minnesota work injuries, whether the 1981 injury was barred by the statute of limitations, the extent of the employee’s permanent partial disability, and apportionment.

In a decision issued on February 6, 2004, the compensation judge determined, in part, that both the 1981 injury at Soil Testing and the 2000 injury at DCI were substantial contributing causes of the employee’s disability after the 2000 injury, and she apportioned responsibility for the employee’s wage loss and need for treatment following that injury as follows: 10% to the 1981 injury at Soil Testing; 65% to the 1991 Texas injuries; and 25% to the 2000 injury at DCI.  However, finding that the statute of limitations had run with respect to the 1981 injury and that she had no jurisdiction over the employee’s Texas employer, the judge held DCI liable for 100% of wage loss and medical expense benefits payable for the period at issue.  The judge denied the employee’s claim for additional permanent partial disability benefits, based on her conclusion that all of the employee’s ratable permanency had occurred prior to the 2000 injury.

After issuance of the judge’s decision, DCI filed a petition to vacate based on newly discovered evidence indicating that Soil Testing had paid benefits following the 1981 injury, so as to toll the statute of limitations.  A panel of this court vacated the judge’s decision and remanded for new findings on the merits.

The first hearing on remand was held on November 2, 2005.  At issue were the employee’s entitlement to benefits for permanent partial disability beyond those already paid by Soil Testing and equitable apportionment of liability for wage loss and medical expense benefits as between Soil Testing and DCI.  Evidence included the employee’s medical records and apportionment/causation opinions from Drs. John Dowdle, Robert Wengler, and Nolan Segal.  It was agreed that the compensation judge could incorporate by reference all findings from her prior decision, except those pertaining to the statute of limitations.

The compensation judge issued her first decision on remand on January 24, 2006.  In that decision, the judge concluded, among other things, that the employee had, in total, a 70% permanent partial disability of the back under the law in effect on the date of the employee’s 1981 injury.  However, using the same equitable apportionment percentages she had applied to wage loss and medical expenses, the judge concluded that Soil Testing was only responsible for a 7% impairment of the back.  Therefore, because Soil Testing had already paid benefits for a 15% impairment of the back, no additional permanency benefits were awarded.  The judge also concluded that Soil Testing could not be held responsible for the (65%) portion of disability attributable to the employee’s Texas injuries^[3] and that DCI was therefore responsible for 90% of the medical expenses and wage loss benefits payable after the employee’s October 4, 2000, work injury, with Soil Testing responsible for the remaining 10%, as equitably apportioned in her original decision.

Both the employee and DCI appealed from the judge’s decision, and, in our August 2, 2006, opinion, this court reversed and remanded again for reconsideration.  With respect to the issue of equitable apportionment, this court determined that the Texas injuries were essentially irrelevant, “no different from a nonwork-related accident or injury,” and that the matter involved simply “a straightforward issue of equitable apportionment between Soil Testing for the 1981 injury and DCI for the 2000 injury.”  The judge was instructed to consider the “usual factors relevant to equitable apportionment,” pursuant to Goetz v. Bulk Commodity Carriers, 303 Minn. 197, 200, 226 N.W.2d 888, 891, 27 W.C.D. 797, 800 (1975).

On the issue of permanent partial disability, this court concluded that equitable apportionment to the Texas injuries was not permissible, and we instructed the judge to determine whether the employee’s 1981 injury at Soil Testing was a “substantial contributing cause of the permanent partial disability for which benefits have been sought.”  (Emphasis is original).  That issue, we explained, was not dependent on principles of equitable apportionment but rather on legal and medical causation.

The second hearing on remand was held on January 4, 2007.  No additional evidence was submitted, but the parties argued their positions and submitted memoranda to the compensation judge.  In her most recent decision, the compensation judge determined that the employee’s Texas injuries were superseding, intervening causes of the employee’s disability, acting to cut off Soil Testing’s liability.  As such, the judge denied the employee’s claim for additional permanent partial disability benefits, and she ordered DCI to pay 100% of the medical and wage loss benefits due after the employee’s October 4, 2000, work injury.  The employee and DCI appeal.

On appeal, the Workers’ Compensation Court of Appeals must determine whether “the findings of fact and order [are] clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.”  Minn. Stat. § 176.421, subd. 1 (2006).  Substantial evidence supports the findings if, in the context of the entire record, “they are supported by evidence that a reasonable mind might accept as adequate.”  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 59, 37 W.C.D. 235, 239 (Minn. 1984).  Where evidence conflicts or more than one inference may reasonably be drawn from the evidence, the findings are to be affirmed.  Id. at 60, 37 W.C.D. at 240.  Similarly, findings of fact should not be disturbed, even though the reviewing court might disagree with them, "unless they are clearly erroneous in the sense that they are manifestly contrary to the weight of the evidence or not reasonably supported by the evidence as a whole.”  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).

“[A] decision which rests upon the application of a statute or rule to essentially undisputed facts generally involves a question of law which [the Workers' Compensation Court of Appeals] may consider de novo.”  Krovchuk v. Koch Oil Refinery, 48 W.C.D. 607, 608 (W.C.C.A. 1993).

In her first decision of February 6, 2004, the compensation judge concluded that the employee’s 1981 injury with Soil Testing was responsible for 10% of the employee’s wage loss and need for treatment following the October 4, 2000, injury at DCI.  However, concluding that claims against Soil Testing were barred by the statute of limitations, the judge ordered DCI to pay all such benefits.  In her subsequent January 24, 2006, decision, the judge again concluded that the 1981 injury was responsible for 10% of the claimed wage loss and medical expense benefits, finding as follows:

At no point in our prior decision did we direct the compensation judge to reconsider whether the 1981 injury remained a substantial contributing cause of the employee’s wage loss and medical treatment following the 2000 DCI injury.  Rather, the purpose of the remand was to allow the judge to make a factual determination as to the appropriate percentages for apportionment between Soil Testing and DCI.  Moreover, by originally finding Soil Testing liable for 10%, the judge had already implicitly determined that the Texas work injury or injuries were not superseding, intervening causes of the employee’s disability, and we noted in our decision that there was no argument, on that issue, to the contrary.^[4]  Given the history of the case, the judge was not free to reconsider either whether the 1981 injury remained a substantial contributing cause or, by extension, whether the Texas injuries constituted superseding, intervening causes of the employee’s disability.  As such, Soil Testing is liable, at a minimum, for 10% of the employee’s wage loss and medical expenses following the 2000 injury at DCI.

Under other circumstances, we would remand the matter, yet again, for reconsideration and new findings allocating liability for the benefits at issue between Soil Testing and DCI.  Equitable apportionment involves peculiarly factual conclusions best suited for a compensation judge to make, with review by this court.  See, e.g., Giem v. Robert Giem Trucking, 46 W.C.D. 409, 418 (W.C.C.A. 1992).  However, the first hearing before the compensation judge took place nearly four years ago, the matter has already been before this court three times, and all parties have urged us to avoid another remand.  Consequently, under these unusual circumstances, this court will use its authority pursuant to Minn. Stat. § 176.421, subd. 6(3), to resolve this issue.

In her first two decisions, the compensation judge found Soil Testing liable for 10% of the employee’s wage loss and medical expenses based in part on the apportionment opinion of Dr. Segal.  The judge also expressly determined that the 1981 injury was not de minimus but was rather a substantial contributing cause of the employee’s disability.  The judge did not apportion more than 10% to the 1981 injury in part because, as the judge explained, “the employee went more than 10 years while performing strenuous work with no symptoms and no medical care up to his first Texas work injury in 1991.”  In contrast, the judge found that “[t]he 2000 work injury changed the employee’s failed fusion at L4-5 from a condition he could live with to one that required additional treatment,” that the employee had the “most stringent lifting restriction” ever recommended after the 2000 injury, and that, “[a]fter October 4, 2000, the employee’s low back never returned to the condition it had been in before then.”  These conclusions are amply supported by the record and justify the compensation judge’s original decision apportioning 10% liability for wage loss and medical expenses to Soil Testing.^[5]  See Goetz v. Bulk Commodity Carriers, 303 Minn. 197, 226 N.W.2d 888, 27 W.C.D. 797 (1975).  As this result is most consistent with the judge’s original factual findings, we modify the judge’s decision to reflect that Soil Testing is responsible for 10% and DCI 90% of the employee’s wage loss and medical expense benefits after October 4, 2000.

As noted earlier in this decision, it is undisputed, for purposes of this appeal, that the employee has a 70% permanent partial disability of the back and that all ratable permanent impairment preexisted the employee’s October 4, 2000, work injury, meaning that DCI has no liability for permanent partial disability benefits.  See Minn. Stat. § 176.101, subd. 4a.  Soil Testing originally paid the employee benefits for a 15% permanent partial disability of the back following the employee’s injury in 1981, and the employee contended that Soil Testing was liable for the remaining 55% impairment for which he has not yet been compensated.

In her decision following the most recent remand, the compensation judge denied the employee’s permanent partial disability claim, concluding that the 1991 Texas injuries constituted superseding, intervening causes of the employee’s disability.  In doing so, the compensation judge cited evidence indicating that it had been discovered, during the surgery following the 1981 injury, that the employee did not in fact have a herniated L4-5 disc; the fact that the employee did very well, performing heavy work with few symptoms, until the 1991 Texas injuries; and the fact that no doctor had specifically tied the employee’s later symptoms and need for treatment, including fusion, to the L4-5 level, affected by the 1981 work injury, as opposed to the L5-S1 level of the employee’s spine.

We understand the compensation judge’s reluctance to impose liability on Soil Testing for a 70% permanent partial disability given her equitable apportionment decision and the arguable insignificance of the 1981 injury in the employee’s long history of back injuries and treatment.  Again, however, the compensation judge was not free, at this stage of the proceedings, to conclude that the 1991 Texas injuries constituted superseding, intervening causes of the employee’s disability.  Rather, the purpose of the remand was to allow the judge to consider whether a specific permanency rating should be assigned solely to the Texas work injuries.  See Fleener v. CBM Indus., 564 N.W.2d 215, 56 W.C.D. 495 (Minn. 1997)(attributing specific permanency ratings to discrete work injuries has nothing to do with equitable apportionment).  After further review of the evidence, we conclude that the employee is entitled to additional permanent partial disability benefits, as claimed, from Soil Testing.

In his 2003 report, Dr. Segal indicated that the employee’s 1981 surgery, performed to treat the 1981 injury, was a substantial contributing cause of the employee’s ongoing back problems.  Dr. Wengler testified that the 1981 injury and resulting surgery had compromised the L4-5 disc fibers, that “everything pivots off that [L4-5] disc,” because the initial surgery made the employee susceptible to subsequent problems.  Dr. Dowdle similarly testified that removal of disc material in surgery “causes the disc to degenerate further,” leading to “more possibilities of having problems in the future,” and it was his opinion that the 1981 injury was a substantial contributing factor in the employee’s post-2000 disability and need for treatment.  Taken together, these opinions and the compensation judge’s original factual determinations lead to the conclusion that the 1981 injury is a substantial contributing cause of the employee’s overall 70% permanent partial disability of the back.

We recognize that holding Soil Testing liable for a 70% impairment appears inconsistent with the conclusion that the 1981 injury is responsible for only 10% of the employee’s wage loss and need for treatment.  However, Soil Testing’s liability for permanent impairment results not from the equitable considerations underlying apportionment between two Minnesota work injuries but from legal principles applicable in cases where a portion of the employee’s disability is attributable to an injury not compensable under the Minnesota Workers’ Compensation Act.  As we said in our prior decision, we are unaware of any statute or case law that would require an employee to claim benefits in another state for permanent impairment substantially attributable to a Minnesota work injury.  We also note that it appears, in fact, that the employee did not receive benefits for permanency from his Texas employer.^[6]  Therefore, because the employee’s 1981 injury is, pursuant to the compensation judge’s original decisions and most medical opinions, a substantial - - that is, legal - - cause of the employee’s 70% impairment, Soil Testing is liable for the claimed additional benefits, and the compensation judge’s decision to the contrary is reversed.