Lovegreen and its insurer appeal from the compensation judge’s determination that the employee’s 1980 work injury is a substantial contributing factor in his present condition, from the compensation judge’s finding that the employee’s claim was not barred by a settlement in 1983, and from the compensation judge’s failure to find Gillette injuries in 2003.^[1]  We affirm.

At the hearing in February 2007, Raymond Kelsey was 54 years old and had worked as a journeyman millwright since 1974.  The employee obtained his jobs through the union hiring hall and had worked for numerous employers over the years.  The parties agree that the employee’s job as a millwright, which involved the installation of equipment at power plants and factories, was very physical.

The employee was working for Lovegreen Industrial Services at a location in Red Wing on December 17, 1980.  He was holding a piece of machinery which was being moved by a crane.  When the crane contacted a power line, the employee was electrocuted.  The employee testified that the electricity entered through his left hand and exited through his left foot, blowing his left shoe off in the process.  His hand and foot were bleeding and the force of the shock was enough to throw him to the floor and he landed on his back and struck his head.

The employee was taken to St. John’s Hospital in Red Wing where he was diagnosed with electrical shock and burns.  Charring was noted on his left great toe.  The employee received follow-up care from his physicians at Doctors Clinic in Forest Lake.  The employee was off work for about two months.  Lovegreen and its insurer, State Farm Group, accepted liability and paid workers’ compensation benefits to the employee.

The employee testified that he never completely recovered from his injury.  In 1981, he saw Dr. Stanley Fruchtman who provided a permanent partial disability rating of 10% of the spine for the employee’s recurring lumbar symptoms associated with the injury.  In September 2002, he saw a neurologist, Dr. Paul Schanfield, for headaches he had had since the injury.  Dr. Schanfield diagnosed post-traumatic headaches from the employee’s falling and hitting his head on the floor during the electrical injury.

The employee returned to work as a millwright and shortly after his return to work resumed the full duties of that position.  The employee continued to work full time without restrictions as a millwright through the date of hearing.

The employee and Lovegreen entered into a settlement in 1983 which was the subject of an award on August 26, 1983.  The stipulation provided, in relevant part, “it is the intention of the parties by and through this stipulation, to fully finally and completely settle any and all claims which the employee may have under the Worker’s Compensation Act, except future medical expenses.”

At the hearing in February 2007, the employee claimed payment for medical expenses incurred in treating his left shoulder, left hip, ankle, and foot, from May 2003 to the date of hearing.  Lovegreen denied liability for the treatment, arguing that the 1980 work injury was not a substantial contributing factor in the need for treatment, that the 1983 agreement barred the employee’s claims, and that liability was more properly placed on Gillette injuries the employee allegedly sustained in 2003.

Support for the employee’s claim was provided by Dr. David Kittleson, an orthopedic specialist at Summit Orthopedics.  Dr. Kittleson began treating the employee in April 2004 for severe glenohumeral arthritis in the left shoulder.  It was Dr. Kittleson’s opinion that shoulder replacement surgery would be appropriate when the employee’s symptoms warranted but because the surgery could preclude the employee’s continuing work as a millwright, the procedure would be postponed.

On the issues involved at the hearing, Dr. Kittleson prepared two narrative reports.  It was his opinion, as expressed in the reports, that the 1980 work injury was a “substantially contributing cause” in the employee’s left shoulder arthritis, as well as his left hip, knee, and ankle complaints.  Dr. Kittleson found to be significant the fact that the most severe injury at the time of the electrical shock was to the employee’s left side and the lack of symptoms on the employee’s right side, given that the employee is right-hand dominant.  Dr. Kittleson attributed the left shoulder arthritis to a thermal injury to the articular cartilage that degenerated over time.  Dr. Kittleson also noted the lack of other explanations for the employee’s complaints.  In his second report, he was advised of the IME report from Dr. Thomas Comfort and of a possible left shoulder dislocation at some point in the early 1980s.^[2]  The additional information did not change his opinion.

The employee also presented a report from a neurologist, Dr. Thomas Jacques.  The employee had been referred by his family doctor to Dr. Jacques’ colleague, Dr. Nadeem Iqbal, in October 2003.  The employee complained of left hand weakness and numbness.  Dr. Iqbal noted that an electrical injury could result in demyelination which would produce such symptoms and he recommended further diagnostic tests.  The tests were non-diagnostic and Dr. Iqbal concluded that the employee’s symptoms were due to the extensive degenerative changes in his left shoulder.  In a report of December 13, 2006, prepared in response to an inquiry from the employee’s attorney, Dr. Jacques stated he agreed with Dr. Kittleson’s opinion and deferred to him on the orthopedic nature of this case.

Dr. Thomas Comfort saw the employee for an IME on April 6, 2006, on behalf of Lovegreen.  It was his opinion that there was no relationship between the 1980 work injury and the employee’s left shoulder complaints.  He stated

Based on Dr. Comfort’s report, the employee amended his claim to include Gillette injuries in May or June, 2003 and October 2003.  In May and June 2003, the employee was working for Egan Mechanical, insured by Risk Enterprises Management, and in October 2003, he was employed by Pro-Tec Industrial Services, insured by Minnesota Assigned Risk Plan.

Egan had the employee evaluated by Dr. William Simonet on August 30, 2006.  Dr. Simonet did not believe that the employee had incurred a Gillette injury to his shoulder nor did he accept that the 1980 injury was a causative factor.  It was his conclusion that the employee had age-appropriate arthritis with complaints out of proportion to physical findings.  He did agree, however, “he might require total shoulder arthroplasty at some point.”

Pro-Tec had the employee evaluated by Dr. Richard Strand on November 1, 2006.  Dr. Strand’s opinion was that the left shoulder problems were not due to the 1980 injury or a Gillette injury.  He placed primary responsibility on the employee’s alleged shoulder dislocation “which occurred prior to his electrical injury.”  In her findings and order of April 27, 2007, the compensation judge determined that the employee had

Lovegreen argues on appeal that the compensation judge erred in finding that the 1980 work injury was a significant contributing factor in the employee’s current condition and need for treatment.  According to Lovegreen, the medical opinions relied upon by the compensation judge, primarily that of Dr. Kittleson, lacked foundation and, further, that substantial evidence does not support the compensation judge’s decision.

In considering whether a doctor has adequate foundation to provide a medical opinion, this court has generally applied Scott v. Southview Chev. Co., 267 N.W.2d 185, 188, 30 W.C.D. 426, 430 (Minn. 1978).  Sufficient knowledge of the subject matter to establish foundation may be obtained through personal knowledge, a hypothetical question, or testimony.  Here, Dr. Kittleson had treated the employee, had reviewed prior medical records, and had been given additional information by the employee’s attorney.  This information provides sufficient foundation for Dr. Kittleson’s opinion.  Wiggin v. Marigold Foods, slip op. (W.C.C.A. July 29, 2004).

Lovegreen argues, however, that the issue in the present case - - the causal relationship between an electrical injury and arthritis - - is so unusual that specific knowledge of electrical injuries must be shown in order for a doctor to have foundation for an opinion on this subject.  The absence of this knowledge results in speculation, according to Lovegreen.  We disagree.

None of the IME doctors in this case suggested that knowledge beyond that typically possessed by an orthopedic specialist was necessary.  While both Dr. Strand and Dr. Comfort refer to doing a literature search, there was no suggestion from either doctor that he placed special weight on the results of his search or that in the absence of this search he would have been unable to render an opinion on the issue.  We conclude, therefore, that the question of additional knowledge or expertise in this area goes to the weight to be afforded the opinion.  This result is most consistent with our case law involving similar issues.  Cull v. Walmart Stores, Inc., 64 W.C.D. 62 (W.C.C.A. 2004); Webb v. Hercules, Inc., 64 W.C.D. 519 (W.C.C.A. 2004); and Schulenburg v. Corn Plus, 65 W.C.D. 237 (W.C.C.A. 2005).

In his response to Lovegreen’s brief, the employee argues that Lovegreen has waived this issue on appeal by failing to raise the issue at the hearing level.  Lovegreen’s response is that the issue was raised by the introduction of the medical articles Dr. Comfort apparently found in his literature search.  Lovegreen further states that Minn. Stat. § 176.155 mandates the admission of reports such as Dr. Kittleson even though foundation may be lacking.

It is correct to note that compensation judges typically admit medical reports into evidence despite a foundation objection, probably because many attorneys are actually arguing that the opinion in the report should be given little weight.  Still, simple fairness to opposing parties and to the compensation judge would mandate that a party who claims that reliance on the report is error as a matter of law should advise the compensation judge of that argument.  That was not done here.  Given our decision on the issue of foundation of this case, we have chosen not to consider this question further.

Lovegreen also contends that the decision of the compensation judge lacks the support of substantial evidence.  The compensation judge, in her decision and her memorandum, specifically adopted the opinions of Dr. Kittleson and Dr. Jacques.  Essentially, Lovegreen argues on appeal that Dr. Kittleson did not place enough importance on the information which the IME doctors, especially Dr. Simonet, found to be important.  It is the role of the compensation judge to consider the competing medical opinions and to determine which opinion is most persuasive.  We have said in a number of cases that a compensation judge’s decision based on that choice is generally upheld.  We reach that conclusion in the present case as well.  Smith v. Quebecor Printing, Inc., 63 W.C.D. 566 (W.C.C.A. 2003); Maricle v. Farmstead Foods, No. WC06-289 (W.C.C.A. June 14, 2007); Johnson v. Sico, Inc., No. WC05-226 (W.C.C.A. Jan. 20, 2006).

The compensation judge determined that the employee did not sustain a Gillette injury in May 2003 while working at Egan or in October 2003 while at Pro-Tec.  The compensation judge stated there was no legally sufficient disablement on either of those dates.  Lovegreen argues that the compensation judge erred because she failed to apply this court’s holding in Shaffer v. The Minnesota Orchestra, 53 W.C.D. 341 (W.C.C.A. 1995). It is true, as Lovegreen points out, that, pursuant to Shaffer, an employee’s medical appointment may be one of the “ascertainable” events showing that a Gillette or minute trauma injury has occurred.  In the present case, however, we do not agree that the doctor visits in 2003 constituted evidence of ascertainable events.

The only medical opinion that the employee had a Gillette injury was that of Dr. Comfort.  His report, dated April 6, 2006, does not identify a date when that Gillette injury was made manifest.  The report places no importance on the medical appointments in May and October 2003; Dr. Comfort simply listed them along with many other appointments in the medical history portion of his report.  Further no other doctor found any significance in the medical visits in the employee’s symptoms, work activity, or need for further treatment.

Determination 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).  Given the lack of medical evidence in the present matter, we are unable to conclude the compensation judge erred in finding that the employee did not sustain a Gillette in May/June or October 2003.

The compensation judge decided that the 1983 stipulation did not preclude the employee’s claims against Lovegreen.  Lovegreen argues the compensation judge erred.  While medical expenses were left open by the stipulation, Lovegreen contends that only certain future medical expenses were contemplated by the parties.  It is Lovegreen’s position that only those medical conditions identified in contemporaneous medical reports should be considered open.

The plain language of the stipulation is that future medical expenses related to the December 17, 1980, work injury were still available to the employee.  There is absolutely no language in the stipulation which purports to limit those expenses.  As a result, the question for the compensation judge was whether the 1980 work injury was a substantial contributing cause of the employee’s medical treatment and resulting bills.  The compensation judge found the work injury to be a substantial contributing factor and properly determined that the stipulation did not bar the employee’s claims.

The compensation judge’s decision is affirmed.