Cima Labs, Inc., and its insurer appeal from the compensation judge’s decision that the employee sustained a Gillette-type injury^[1] to her low back, while employed by Cima Labs, that was responsible for two-thirds of the employee’s subsequent disability and need for treatment.  We affirm.

On August 18, 1999, the employee sustained an admitted Gillette-type injury to her low back while employed as a machine operator by Quali Tech, Inc., a food processing company.  X-rays taken the following month revealed “[b]orderline grade 1-2 spondylotic spondylolisthesis of L5, secondary to bilateral pars defects,” and “[a]t least mild to moderate degenerative disc disease at L5-S1.”

The employee’s regular job at Quali Tech required repetitive heavy lifting, and, for some period after the injury,^[2] the employee was assigned to light-duty work.  Eventually, however, she resumed her usual job duties.  Treatment for the injury consisted primarily of chiropractic care, which the employee received through November of 2001.  The employee did not miss any time from work due to her low back condition, but she testified that her low back pain and leg numbness never completely resolved, with her symptom level typically at 2, on a scale of 1 to 10, during her employment by Quali Tech.

In June of 2003, the employee left her job at Quali Tech for personal reasons,^[3] and, in July of 2003, she began working for Cima Labs, Inc., a manufacturer of pharmaceutical products.  The employee was assigned to the “blister line,” where she monitored machines assembling foil blister packs of medication.  Workers on this line had to load the machines with 50-60 pound rolls of foil.  The employee testified that, initially, she would load the rolls of foil into the machines three or four times per 12-hour shift and that her work required bending, stooping, and lifting overhead.

A few weeks after starting her job at Cima Labs, the employee resumed chiropractic treatment for low back and leg pain.  The employee associated her increased symptoms with lifting the rolls of foil, and, at some point, she began arranging for other workers to lift the foil when possible.  She testified, however, that she continued to have to lift foil at least occasionally, and she also testified that certain other work activities, such as bending over to scoop foil waste material out of a bin, seemed to increase her low back pain.

By the fall of 2005, the employee’s low back and leg pain had become severe, and her chiropractor referred her to an orthopedic surgeon.  An MRI scan performed in late December 2005 disclosed multi-level degenerative disc disease and Grade II spondylotic spondylolisthesis as well as mild to moderate bilateral foraminal stenosis at L5-S1.  Dr. Bruce Bartie eventually recommended that the employee undergo fusion surgery, and the employee has not worked, due to her low back condition, since about December 16, 2005.^[4]

The matter came on for hearing before a compensation judge on March 1, 2007.  Issues at that time included whether the employee’s August 18, 1999, injury at Quali Tech was temporary or permanent, whether the employee had sustained a Gillette injury on December 16, 2005, arising out of an in the course of her employment with Cima Labs, and whether liability for claimed wage loss and medical expenses, including the proposed surgery, should be equitably apportioned.  Evidence submitted at hearing included the testimony of the employee and of two of the employee’s supervisors at Cima Labs; the employee’s medical records; and the opinions of independent medical examiners Drs. Mark Gregerson and Paul Wicklund.

In a decision issued on March 8, 2007, the compensation judge concluded that the employee had sustained a Gillette injury on December 16, 2005, in her job at Cima Labs, as claimed, and that the 1999 injury at Quali Tech and the 2005 injury at Cima Labs both substantially contributed to the employee’s disability, wage loss, and need for treatment, including surgery, for the period at issue.  Liability for benefits was apportioned one-third to Quali Tech and two-thirds to Cima Labs.  Cima Labs 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).

Compensation is payable for injuries that occur as a result of repetitive minute trauma caused by an employee’s work activities.  See Gillette v. Harold, Inc., 257 Minn. 313, 101 N.W.2d 200, 21 W.C.D. 105 (1960).  In order to establish a Gillette injury, an employee must “prove a causal connection between [her] ordinary work and ensuing disability.”  Steffen v. Target Stores, 517 N.W.2d 579, 581, 50 W.C.D. 464, 467 (Minn. 1994).  “[T]he question of a Gillette injury primarily depends on medical evidence.”  Id.

In the present case, the compensation judge determined that the employee had sustained a Gillette injury in the course and scope of her employment with Cima Labs, culminating in disability on December 16, 2005.  Cima Labs’ argument on appeal focuses almost entirely on the nature of the employee’s work.  Specifically, Cima Labs argues that the record does not support the conclusion that the employee’s lifting at Cima Labs caused her subsequent disability, in that the employee stopped lifting foil on a frequent basis not long after starting work there, and two supervisors testified that they had never observed employee lift foil rolls in the two-and-one half to three years they had worked with her.  We are not persuaded.

The compensation judge’s findings on this issue read, in part, as follows:

Cima Labs also appeals from the compensation judge’s decision apportioning liability for the employee’s disability and need for treatment one-third to the 1999 injury at Quali Tech and two-thirds to the 2005 injury at Cima Labs.  We cannot conclude that the compensation judge’s decision is clearly erroneous or unsupported by substantial evidence.

Factors relevant to an equitable apportionment decision include the nature and severity of the initial injury, the employee’s symptoms following the initial injury up to the occurrence of the second injury, and the nature and severity of the second injury.  Goetz v. Bulk Commodity Carriers, 303 Minn. 197, 200, 226 N.W.2d 888, 891, 27 W.C.D. 797, 800 (1975).  In the present case, considerations supporting the compensation judge’s decision include the fact that the employee was ultimately able to return to her usual, heavy work activities at Quali Tech following her 1999 injury, the fact that the employee lost no time from work at all, due to her back condition, prior to the December 16, 2005, injury at Cima Labs, the employee’s lack of low back treatment for about a year and a half prior to her commencing work with Cima Labs in July of 2003, the fact that surgery had never been recommended prior to the employee’s injury at Cima Labs, and the employee’s testimony that her pain level stayed at about a 2, on a scale of 1 to 10, until she began her job at Cima Labs.

We acknowledge that the record might also support the conclusion that the employee’s current disability and need for treatment are largely if not entirely the result of a natural progression of the 1999 injury, superimposed on the employee’s preexisting condition.  However, the fact that some other conclusion could have been drawn from the evidence is irrelevant; the issue is whether the record supports the determination reached by the compensation judge.  Because the judge’s causation and apportionment decisions here were reasonable, we affirm the judge’s decision in its entirety.