The self-insured employer appeals from the compensation judge’s primary liability finding, from the judge’s award of temporary total disability benefits and of medical expenses to non-intervening providers, and from the judge’s failure to apportion permanent partial disability.  We reverse the judge’s award of temporary total disability benefits for the period August 17, 2007, through October 14, 2007, and remand for further proceedings consistent with this opinion.  As to the remainder of the issues on appeal, we affirm.

The employee has a history of low back or radiating right leg symptoms^[1] dating back to at least the spring or summer of 2004, when he fell about six feet from a ladder while working as an independent contractor in the construction industry.  He subsequently received chiropractic and medical care for this condition for about a year.  During this period, in July of 2004, he underwent an MRI scan, which disclosed multilevel degenerative changes and disc herniations at L3-4, L4-5, and L5-S1.  The employee testified that his leg symptoms resolved following treatment, and he apparently missed no time from work as a result of those symptoms prior to his employment with the employer herein.

The employee began working for Shaw Stewart Lumber Company [the employer] in about February of 2006.  According to a report from his pre-employment screening evaluation, the employee “handled all weights and tasks well,” demonstrating the ability to lift 100 pounds and carry 50 or 60 pounds in the manner instructed by the evaluator.  The title of the employee’s position with the employer was “yard man driver.”  At first, the employee worked primarily in the lumber yard, loading trucks, either manually or using a forklift, with construction materials.  In about March of 2007, the employee became a delivery driver, which the employee testified was a much more demanding job, requiring frequent twisting and bending and very heavy lifting and carrying of construction materials such as sheetrock, windows, and doors.

After beginning his job with the employer, the employee sought treatment on a few occasions for recurrent low back or right leg symptoms, and a medical record from February of 2007 indicates that the employee generally experienced flare-ups of his condition every three to six months.  Again, however, the employee apparently continued performing heavy labor for the employer, without time off due to his low back condition, until the summer of 2007.

On July 3, 2007, the employee was seen by his usual chiropractor for “some back pain,” “most in right side down leg 1 week,” unrelated to any specific incident.  About a month later, on August 2, 2007, the employee was called into the employer’s office to discuss a driving ticket issued to the employee while working.  At that time, the employee told Peg Sweeney, the employer’s human resources manager, that he had been bothered by leg pain while driving and sitting in traffic on the job.  The next day, the employee signed an “Employee’s Report of Accident or Close Call,” indicating that he had awoken “one morning with pain in the back of my leg consistent with a disc herniation.  I didn’t think much of it - just thought I needed an adjustment.  Over the next two weeks the pain got worse & worse.”

Also on August 3, 2007, the employee was evaluated for right posterior leg pain by Dr. Austin Indritz, who noted that the employee could not recall any specific precipitating incident but that his symptoms were aggravated by prolonged sitting.  When the employee returned to Dr. Indritz on August 15, 2007, the doctor restricted the employee from driving at work and limited his lifting, pushing, and pulling.  Dr. Indritz also prescribed physical therapy and a Medrol Dosepak and recommended that the employee undergo an MRI scan.  That scan, performed on August 22, 2007, was interpreted as showing a large disc protrusion at L5-S1, with compromise of the right paracentral canal and displacement/mass effect upon the descending right S1 nerve root, as well as disc protrusion and other degenerative changes at L4-5 and L3-4.

Conservative treatment, including two therapeutic injections, failed to alleviate the employee’s symptoms, and on October 15, 2007, the employee underwent a minimally invasive decompression/discectomy at L5-S1, performed by Dr. Stefano Sinicropi.  The employee was subsequently off work until December 17, 2007, when he was released to return to his usual job, without restrictions, and he resumed employment with the employer.

The employee claimed entitlement to various benefits as a result of a Gillette injury^[2] allegedly occurring on about August 2, 2007.  The self-insured employer denied primary liability, and the matter came on for hearing before a compensation judge on July 23, 2008.  Issues included whether the employee had sustained a Gillette injury as claimed, the employee’s entitlement to temporary total disability benefits from August 17, 2007, to December 17, 2007, the employee’s entitlement to benefits for an 11% whole body impairment, the date of maximum medical improvement, and the self-insured employer’s liability, if any, for medical expenses.  Evidence included causation opinions from Dr. Sinicropi, the employee’s surgeon, and Dr. Mark Engasser, the employer’s examiner; the employee’s medical records and testimony; and a report, testimony, and a DVD related to surveillance of the employee in September of 2007.

In a decision issued on August 7, 2008, the compensation judge concluded that the employee had sustained a Gillette injury, as claimed, and she awarded the claimed temporary total benefits, permanent partial disability benefits, and medical expenses, including medical expenses incurred for treatment with certain providers who failed to intervene.  The employer appeals.

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 (2008).  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 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 Gillette injury occurs when an employee is disabled as a result of repeated trauma caused by the duties of the employee’s employment.  See Gillette v. Harold, Inc., 257 Minn. 313, 321-22, 101 N.W.2d 200, 205-06, 21 W.C.D. 105, 111-13 (1960).  The question of a Gillette injury depends primarily on the medical evidence.  Steffen v. Target Stores, 517 N.W.2d 579, 581, 50 W.C.D. 464, 467 (Minn. 1994).  “Whether given by testimony or written report, an opinion by a medical expert as to the causal link between the claimant’s disability and the job must be based on adequate foundation.”  Id. at 582, 50 W.C.D. at 467.

In the present case, Dr. Sinicropi, the employee’s surgeon, wrote as follows on the issue of causation and the employee’s permanent impairment:

Dr. Engasser, the employer’s independent medical examiner, agreed that the employee had an 11% whole body impairment due to his low back condition.  He concluded, however, that the employee’s condition was not causally related to his work for this employer, explaining,

On appeal, the employer argues primarily that the compensation judge erred in accepting Dr. Sinicropi’s opinion on causation, in that Dr. Sinicropi’s opinion lacked foundation.  More specifically, the employer contends that Dr. Sinicropi lacked complete information about the employee’s preexisting condition and treatment history and that he erroneously assumed that the employee had recovered from his 2004 fall from the ladder within six months, without additional problems.  The employer further contends that Dr. Sinicropi was unaware of the employee’s belief that lifting, standing, and walking at work had not aggravated his symptoms and that the employee had noticed increased pain only when sitting, whether at home or at work.  In fact, the employer alleges, only Dr. Engasser had all of the information and records necessary to render an opinion on causation.  We are not persuaded.

The employee’s attorney submitted two informational letters to Dr. Sinicropi, as well as medical records from some of the employee’s treatment in 2004, including - - contrary to the  employer’s suggestion - - the employee’s July 6, 2004, MRI report.  Moreover, the employee’s attorney also provided Dr. Sinicropi with Dr. Engasser’s narrative report, and that report contains much, if not all, of the information Dr. Sinicropi allegedly lacked.  The compensation judge expressly concluded that Dr. Sinicropi had adequate foundation for his opinion, and we cannot disagree.  As such, we cannot conclude that the judge erred in accepting Dr. Sinicropi’s opinion on foundation grounds.

The employer also contends that the employee did not meet his burden of proof, because he did not adequately describe his specific work activities over the course of a typical work day, such as the frequency of repetitive acts, the weights involved, distances covered, and the like.  Without such detailed explanation, the employer maintains, medical experts have no basis upon which to render an opinion connecting an employee’s work to the employee’s condition and resulting disability.  Again, we are unpersuaded.

It is essentially undisputed here that the employee performed very heavy lifting and carrying in his job with the employer.  We are satisfied that the employee submitted adequate information to meet his burden of proof, and we, like the compensation judge, find little relevance in the fact that the employee himself only noticed an increase in symptoms while sitting, not while lifting or carrying.  We similarly reject the employer’s contention that case law has effectively eroded the standard for Gillette injuries so as to improperly shift the burden of proof from the employee to the employer.

Given the essentially undisputed evidence as to the very strenuous nature of the employee’s work, and given Dr. Sinicropi’s opinion that that work substantially contributed to the employee’s low back condition, need for treatment, and disability, we affirm the judge’s finding on liability.

The employee’s testimony and surveillance records indicate that the employee finished constructing two dog houses in September of 2007.  While he testified at one point that he was engaged in this activity as a favor to his girlfriend, he also admitted that he was paid for the work.^[3]  Given this evidence, the employer contends that the compensation judge erred in awarding temporary total disability benefits from August 17, 2007, when the employee was restricted from driving at work, until October 15, 2007, the date of his surgery, in that the employee was working in a side job, for money, during this period.

Generally, an employee who is working may not receive benefits for total disability unless his earnings are too sporadic or unsubstantial to establish an earning capacity.  See, e.g., Schulte v. C.H. Peterson Constr. Co., 278 Minn. 79, 153 N.W.2d 130, 24 W.C.D. 290 (1967).  In the present case, there is no evidence as to exactly what the employee earned building dog houses, and under other circumstances we might simply have reversed the compensation judge’s temporary total disability benefit award.  There is, after all, no basis in the record that would allow us to simply assume that the employee’s earnings were insubstantial.  At the same time, however, the employer did not defend against the employee’s temporary total disability claim on grounds that the employee was earning income during the period in question.  Rather, it appears that the employer was contending that the employee was not medically unable to continue performing his pre-injury job.  As such, the employer has arguably raised a new defense on appeal.

Parties must be afforded reasonable notice and opportunity to be heard before decisions on benefits made be made.  See Kulenkamp v. Timesavers, Inc., 420 N.W.2d 891, 40 W.C.D. 869 (Minn. 1988).  Given the way the case was litigated, we conclude that the matter should be remanded to allow the parties to submit the evidence necessary to determine the employee’s entitlement to wage loss benefits for the period August 17, 2007, through October 14, 2007.  If the evidence presented indicates that the employee had more than insubstantial income attributable to work performed during this period, the judge may consider whether the employee is entitled to temporary partial rather than temporary total disability benefits.

The compensation judge concluded that the employee was entitled to benefits for an 11% whole body impairment as a result of his work injury.  Both Dr. Sinicropi and Dr. Engasser assigned an 11% rating, and the employer does not dispute the employee’s overall permanency rating on appeal.  The employer argues, however, that the compensation judge erred in failing to apportion the employee’s preexisting permanent partial disability pursuant to Minn. Stat. § 176.101, subd. 4a.  Because, the employer contends, the employee had a 9% whole body impairment prior to his work injury, the employer should only be responsible for benefits for the additional 2% rating.  This argument has no merit.

We find no indication anywhere in the record that the employer raised the issue of apportionment for preexisting permanent partial disability at the trial level.  And, contrary to the employer’s argument, we do not believe that apportionment is automatically part and parcel of a permanent partial disability claim, even if there is evidence of preexisting disability.  Apportionment of permanent partial disability is not merely a numerical exercise; the employer must establish that the employee was functionally disabled, prior to his work injury, within the meaning of Beck v. Dick & John’s Price Rebel, 40 W.C.D. 252 (W.C.C.A. 1987).  By the same token, the employee must be given reasonable opportunity to contest such a claim.  See Kulenkamp, 420 N.W.2d 891, 40 W.C.D. 869.  Because the employer failed to raise the issue of apportionment to the compensation judge, that issue may not be raised on appeal.  See id.; see also Moreno v. Advertising Unlimited, slip op. (W.C.C.A. Jan. 3, 2001) (issues not raised at the hearing level may not be raised for the first time on appeal).  We therefore decline to consider the question further.

The employer acknowledges that the employee documented and claimed medical expenses for treatment rendered by certain providers.  The employer contends, however, that, because those providers did not intervene in the matter as contemplated by Minn. Stat. § 176.361, payment should be barred.  In support of this argument, the employer cites various recently adopted  administrative rules which, they contend, support their position.  See Minn. R. 1420.1850, subps. 1.A., and 4.  We reject this argument.

This court has previously determined that an employee may independently pursue and obtain payment for medical expenses, regardless of whether the providers rendering the treatment have intervened in the matter.  See Adams v. DSR Sales, Inc., slip op. (W.C.C.A. Mar. 12, 2004); Hughes v. Edwards Mfg. Co., 61 W.C.D. 481 (W.C.C.A. 2001).  The rules cited by the employer deal only with settlements and have no applicability whatsoever here.  Because we find nothing in any of the employer’s arguments that would prompt us to reconsider our previous holdings on this issue, we affirm.