The employee, Kevin Murphy, appeals from the compensation judge’s determination that the employee failed to establish by a preponderance of the evidence that he sustained a Gillette^[1] injury to his cervical spine. We affirm.

Kevin Murphy began working for AmeriPride Linen & Apparel Services in 1996 as a customer service representative and was assigned a route to pick up and deliver a variety of textile products from and to customers.

In October 2010, the employee filed a claim petition alleging that he had sustained specific and Gillette injuries to his cervical, thoracic, and lumbar spines on October 7, 2008, November 23, 2009, and July 22, 2010, as the result of his job duties. The parties settled those claims in January 2013.  The stipulation identified the employee’s claims, including his claim that low back surgery performed on November 9, 2010, was related to his injuries on October 7, 2008, November 23, 2009, and July 22, 2010, and that, in addition, he had sustained injuries to his thoracic and cervical spines on the cited dates.  The settlement closed out all claims for the injuries except for certain medical expenses.  The employer and insurer maintained a denial of primary liability as to the claimed injuries.

The present litigation arises out of a medical request filed by the employee in March 2014, in which the employee sought payment of medical expenses related to cervical discectomy and fusion surgery done in January 2014.  The claim was ultimately heard by Compensation Judge John Baumgarth on December 1, 2014.

Mr. Murphy testified in detail at the hearing about his job duties at AmeriPride. When he started to work for the employer, he was assigned to what he referred to as the “Wisconsin route.”  He delivered to customers in northwestern Wisconsin and the route required an overnight stay in Wisconsin as well as driving about 1,000 miles a week.

The employee began his work day by loading his truck with the clean products he would be delivering to his customers.  Rugs came in various sizes and would be taken off a pallet and carried into the truck.  He would then load “flats,” towels and similar items that were folded and often carried into the truck in laundry bags.  Finally, uniforms would be carried into the truck and hung up in the back of the truck.  The amount of product and the weight of product would vary depending on the route that day.  On the route, he would deliver clean items to his customers and pick up dirty items to take back for cleaning.  Mr. Murphy was scheduled to work four days a week, 10 hours a day, but he stated that he often had to work another hour or so each day to get his truck loaded.

The employee’s job changed over the years.  In 2004, he transferred from the Wisconsin route to one covering the west Duluth area.  Also in approximately 2004, the employer added a loading dock to its facility so that the employee could wheel products on and off the truck in carts.  Beginning in 2006 or 2007, the truck used by the employee had a lift gate, making it easier to unload and load items when he was at customers’ stops. The employee agreed that his job was physically easier after that time.  The employee last worked for AmeriPride on November 5, 2010, just before his low back surgery.

The employee’s supervisor at AmeriPride testified at the hearing.  There was some disagreement in the testimonies of the supervisor and the employee as to the weight of the dirty items picked up from customers.  It was generally agreed that these items, especially wet rugs, were the heaviest items he had to carry.  Actual weights appeared to be based on how individual drivers decided to load and unload their trucks.  An advertisement for drivers placed by the employer indicated a route driver needed to be able to lift up to 100 pounds.

The earliest medical records in evidence are from Dr. Craig Gilbertson, the employee’s primary care physician, beginning in 1989 when Mr. Murphy saw Dr. Gilbertson for a right neck strain.  Mr. Murphy saw Dr. Gilbertson for various issues in June 2001, April 2003, March 2004, July 2004, February 2006, and October 2006. There is no mention in any of those records of cervical or neck problems.  Dr. Gilbertson’s chart notes refer to a “head” MRI scan being done in April 2003 to address the employee’s complaints of headaches.  The records contain no information as to the results of the MRI.

The first reference to the employee having neck pain is in the records of the employee’s treating chiropractor, Dr. Robert Torgrimson.  On April 16, 2003, the employee saw Dr. Torgrimson with complaints of “stiff neck.”  The history provided by Mr. Murphy was that the pain came on suddenly while he was doing pushups at home.  The employee was concerned enough about these symptoms that he went to the emergency room.  The employee also reported that he had a CT scan, a spinal tap, and an MRI scan, all of which were “apparently negative” according to Dr. Torgrimson’s notes.

Mr. Murphy had an annual physical done on March 10, 2008, and advised Dr. Gilbertson that he had a stiff neck.  The physical exam was normal and Dr. Gilbertson’s impression was “significant low back pain, neck stiffness.”^[2]  X-rays done at that time showed moderate narrowing at the C6-7 and the C7-T1 disc spaces, mild narrowing at C5-6, small osteophytes anteriorly and posteriorly at C5-6 and C6-7, and some calcification in the anterior longitudinal ligaments at C5-6, C6-7, and C7-T1.

In June 2008, the employee was seen for a rheumatology consultation at the Duluth Clinic by Dr. Ana Fernandez to determine if there was a rheumatological component to his low back pain.  Dr. Fernandez noted during her examination, “no pain with rotation of the neck.”  The impression was “degenerative disc disease of cervical and lumbar spine.”  X-rays of the lumbar spine and a change in medication for his low back pain were recommended.

Mr. Murphy returned to Dr. Gilbertson on August 11, 2008.  He stated that his back and neck felt quite well “when he is not working.”  The impression was of significant neck and back pain.  Dr. Gilbertson recommended an MRI of the neck, “to be sure, especially since this is a work related issue and worse with working.”  The MRI was denied according to Dr. Gilbertson’s chart notes on October 6, 2008, where it was noted that Mr. Murphy “continues to have significant neck pain, worse with work.”  The impression at that time was “significant neck pain.  I think some degenerative arthritis and disk change yet certainly nothing surgical.”

There was no follow-up for any neck problems after that appointment.  In April 2009, Dr. Gilbertson saw the employee for his annual physical.  Some mild limitation of motion of the neck was noted as well as tenderness at the base of the neck.  Dr. Gilbertson’s impression for the neck was “significant degenerative change in the neck, as well, due to his work.”

There are no further complaints, findings on exam, or discussion of any neck or cervical problems for the next 4½ years.  During that time, the employee treated extensively for his low back condition.  In March 2010, there was a consultation with physical medicine and rehabilitation physicians at St. Luke’s.  The employee indicated pain from his upper thoracic to sacrum but had no complaints of neck pain.

Eventually, surgery was done on the employee’s low back at St. Luke’s Hospital on December 8, 2010.  Dr. Marshall Watson performed right hemilaminectomies at L4-L5, L5-S1, discectomy at L4-L5, and foraminotomies at L5-S1.  A functional capacities evaluation was done on May 10, 2011, at St. Luke’s.  Mr. Murphy reported that he was doing well after the surgery.  He did not report any difficulty with the upper extremities and demonstrated significant grip strength in both hands.

On October 1, 2013, Mr. Murphy again saw Dr. Gilbertson for his annual physical.  He reported a number of problems including “chronic back pain from his neck down to his tailbone.”  He says this has been progressively worsening.  Seems to be independent of any type of position or activity.”  Left hand carpal pedal spasms were also reported.  Dr. Gilbertson recommended a cervical MRI scan which was done on October 29, 2013.  The MRI was read as showing moderately severe to severe central spinal stenosis at C5-6, mild to moderate stenosis at C6-7, central disk protrusion C4-5 with mild narrowing of the right C4-5 neural canal, and facet arthrosis from C3-T1.

Dr. Gilbertson referred the employee back to Dr. Watson and Mr. Murphy saw Dr. Watson on November 13, 2013.  Dr. Watson recommended surgery and on January 2, 2014, performed a cervical discectomy at C5-6 and a cervical discectomy with fusion at C6-7.

As support for his claims, the employee presented reports from his treating physicians, Dr. Gilbertson and Dr. Watson.

Dr. Gilbertson’s initial report was dated December 28, 2010, and Dr. Watson’s was dated January 5, 2011.  Both reports were in response to a letter from the employee’s attorney asking for opinions on whether the employee’s low back condition and surgery were related to his work at AmeriPride.  Because the letter did not ask for an opinion as to the cervical spine, neither doctor addressed that issue.  Both Dr. Gilbertson and Dr. Watson, however, were of the opinion that the employee’s lumbar condition was due to his work at AmeriPride.  Dr. Gilbertson also stated that Mr. Murphy’s work has “probably been one of the substantial contributing factors in developing his spinal degenerative changes.”

Dr. Watson issued another report on July 15, 2014, this time in response to a letter from the employee’s attorney asking for a causation opinion on whether the employee’s work activity was a substantial contributing factor in his cervical problems and need for surgery.  Dr. Watson’s response on this issue, in its entirety, was “I believe Mr. Murphy’s work activity contributed to his diagnosis, though there is some evidence that genetics may play more of a role than we had previously known.”

Dr. Mark Carlson, an orthopedic surgeon, evaluated the employee’s low back condition on behalf of the employer and insurer on December 29, 2010.  He examined the employee as a part of his evaluation and reported that the exam of the neck was normal with full range of motion and no tenderness.  It was his opinion that the employee’s spine problems were the result of degenerative disc disease and a non-work injury sustained by the employee at home on July 17, 2010.

The employee was seen for his cervical injury claim by Dr. Hart Garner in an independent medical examination on June 19, 2014.  Dr. Garner noted the employee’s history of heavy physical work in his job at AmeriPride, took a medical history, and reviewed medical records.  Dr. Garner noted receiving chiropractic records from 2003 in which the employee reported that he had a stiff neck and headaches after doing push-ups at home.  Dr. Garner concluded that:

There were two witnesses at the hearing: Mr. Murphy and his supervisor, Joel Budisalovich.  The employee’s testimony focused on the details of his job.  The employee agreed, when asked during cross examination, that his job was easier in the last years of his employment at AmeriPride because of the changes to the trucks made by the employer.  The employee has not worked for AmeriPride since November 2010.  In early 2011, he went to work for a moving company.  Mr. Murphy said his primary duties at the moving company were to deliver and pick up temporary storage units using a truck and moving boxes of files using a two-wheeler.  The employee testified that he had no restrictions regarding his neck while he worked at the moving company.

Mr. Budisalovich stated that he became Mr. Murphy’s supervisor in about 2006.  He had previously been a route driver and was familiar with those duties.  Generally, he agreed with the employee as to the job duties, but he stated that some of the duties could be performed more easily than in the description given by the employee.  Mr. Budisalovich also said that he was aware Mr. Murphy had low back problems that he had attributed to his job and Mr. Murphy had told him on numerous occasions about those problems.  Mr. Murphy had never said anything to him regarding any neck problems.

The compensation judge issued his Findings and Order on December 31, 2014.  The compensation judge found that the employee did not establish by a preponderance of the evidence that he sustained a Gillette injury to his cervical spine culminating on October 7, 2008, November 23, 2009, or July 22, 2010.  The employee has appealed.

The compensation judge determined that “the employee has not established by a preponderance of the evidence that he sustained a Gillette injury to his cervical spine culminating on 10/07/2008, 11/23/2009 or 07/22/2010.” (Finding 19.)  The employee has appealed that determination.

To establish a Gillette injury, the employee must prove a causal connection between ordinary work and disability.  Steffen v. Target Stores, 517 N.W.2d 579, 50 W.C.D. 464 (Minn. 1994).^[3]  The question of whether an employee has proven a Gillette injury is a question of fact for the compensation judge.  Bonilla v. Dakota Premium Foods, No. WC14-5728 (W.C.C.A. Jan. 6, 2015); Jensen v. Aqua Dynamics, No. WC06-138 (Sept. 12, 2006). The issue for this court is whether the compensation judge’s factual determination is supported by substantial evidence.  If so, it is to be affirmed by this court.  Minn. Stat. § 176.421, subd. 1.  Substantial evidence is “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).

The employee asserts that the compensation judge’s decision is not supported by substantial evidence and also contends that the compensation judge applied an incorrect legal standard in determining whether the employee met his burden of proof.

We consider first the question of whether the compensation judge applied an incorrect legal standard in determining whether the employee met his burden of proof in establishing his claim through the medical evidence.  As the employee notes, the appropriate standard in workers compensation cases is not whether the work injury or activity is the sole cause of the disability but whether it is a “substantial contributing factor.”  Roman v. Minneapolis St. Ry. Co., 268 Minn. 367, 380, 129 N.W.2d 550, 558, 23 W.C.D. 573, 592 (1964).

The employee points to a statement in the compensation judge’s memorandum that he was “troubled” by a sentence in Dr. Garner’s report in which Dr. Garner appears to refer to the work at AmeriPride as being a contributing factor to the employee’s cervical spine condition.  The employee asserts that this sentence establishes that Dr. Garner recognized that the work at the employee’s job was a substantial contributing factor in his disability and the compensation judge, in failing to recognize that fact, must have applied an incorrect legal standard in establishing causation.  We are not persuaded.

First, at no point in his decision does the compensation judge state that he is making his determination based on a standard that the work activity must be the sole cause of the injury instead of being a substantial contributing factor in causing a work injury.  The employee’s contention that the compensation judge failed to apply a basic legal standard that is applied in all workers’ compensation cases and that has been established law for more than 50 years is based on an inference the employee draws from a single word “troubled” in the compensation judge’s memorandum.  We find this argument less than convincing given the totality of the evidence.

Second, the word complained of by the employee is not in the compensation judge’s findings but in his memorandum.  In an appeal, the issue before this court is whether the findings of the compensation judge are adequately supported by the evidence.  The purpose of a memorandum is to explain the compensation judge’s basis for a decision but is not a part of the compensation judge’s determination.  Minn. Stat. § 176.371; Cleven v. Marvin Windows, 60 W.C.D. 189, 201 (W.C.C.A. 2000), summarily aff’d (Minn. June 13, 2000); Bundy v. Am. Red Cross, 66 W.C.D. 99, 103 (W.C.C.A. 2005), summarily aff’d (Minn. Mar. 28, 2006).

Third, while the compensation judge might have been “troubled” by some wording in Dr. Garner’s report, in his findings he very specifically adopted Dr. Garner’s  opinion that “in terms of a Gillette type injury, there is nothing to suggest that this has occurred.”  The compensation judge also noted, “Dr. Garner also stated that he found no objective medical support that the employee’s activities at AmeriPride aggravated or accelerated any cervical spine degenerative condition beyond a normal progression.”  (Finding 18.)

Fourth, the employee fails to acknowledge that there is no medical opinion that the employee’s work at AmeriPride was a substantial contributing factor to the employee’s cervical condition.  The employee’s surgeon, Dr. Watson, only identified the employment as a contributing factor, not a substantial contributing factor, and he even qualified that comment by noting that “genetics may play more of a role than we had previously known.”  Dr. Gilbertson’s 2010 report did not address the employee’s cervical condition, although he did refer to “spinal degenerative changes.”  However, since this report was prepared at a time when the employee had no cervical complaints and had not treated for his neck for over a year, his opinion on the issue before the compensation judge in the present litigation cannot be considered as authoritative.

For a Gillette injury to be established, the work must be a substantial contributing factor.  There is no general definition of substantial contributing factor and this court has resisted creating a definition that must be rigidly applied in all cases.  We considered the issue of defining substantial contributing factor in Hamm v. Marvin Windows & Doors, 64 W.C.D. 270, 282 (W.C.C.A. 2004), summarily aff’d (Minn. Jul. 22, 2004).  We said there:

We turn to a consideration of whether substantial evidence exists to support the compensation judge’s decision.  The employee has the burden of proof in establishing by a preponderance of the evidence that he sustained a personal injury arising out of and in the course of his employment.  Minn. Stat. § 176.021, subd. 1; Flaherty v. Globe Aviation Servs., slip op. (W.C.C.A. April 17, 2003).  The compensation judge here found that the employee failed to meet that burden.

The compensation judge identified the evidence he found persuasive in making his decision.  The compensation judge noted that although the employee’s job was strenuous, it was easier after he left the Wisconsin route when the employee’s replacement trucks had lift gates and the employer added a loading dock to its facility so that the employee could use carts to load and unload his truck instead of carrying the product.  Despite the job being heavier before 2004, there is no mention in the medical records of any cervical problems related to work and, in fact, no mention of cervical problems at all.

Despite extensive treatment of the employee’s low back, including surgery in 2010, there were no complaints of cervical problems between October 2008 and October 2013.  A functional capacities evaluation done in 2011, after the lumbar surgery, identified no restrictions or limitations relating to the neck or upper extremities.  In fact, the employee’s need for cervical surgery did not manifest itself until almost three years after he left AmeriPride.  The compensation judge also noted that while the employee complained of his low back problems to his supervisor on numerous occasions, he never mentioned any neck problems.

Given this evidence, we conclude the determination by the compensation judge that the employee failed to establish a Gillette injury to his cervical spine is supported by substantial evidence.  The compensation judge’s decision is affirmed.