The employee appeals from the compensation judge's conclusion that the employee failed to prove that his work injuries were a substantial contributing factor in his need for the medical treatments at issue.  We affirm.

On February 1, 1999, Thomas Hogan sustained an injury to his back in the course of his work as a meat cutter with Super Valu/Cub Foods.  Mr. Hogan [the employee] was thirty-seven years old on the date of his injury.  About a year later, on January 1, 2000, the employee was treated by Dr. Thomas Neitzke for symptoms of right shoulder pain, which the employee indicated he had had “on and off for eight years.”  X-rays were negative, and, noting that an MRI just eight months earlier had revealed only “inflammation,” Dr. Neitzke diagnosed possible tendinitis or bursitis and prescribed medication and ice/heat therapy.

About a month later, on February 20, 2000, the employee sustained a second work-related injury to his back, while still working as a meat cutter for Super Valu/Cub Foods [the employer].  On February 25, 2000, he saw Northworks Occupational Health physician Dr. Jennifer Heubner, to whom he complained of a slow onset of pain in his low back that had begun to radiate down into his right leg to the level of his knee.  Dr. Heubner diagnosed a work-related acute lumbar strain, prescribed medication and icing, and released the employee to return to work with lifting and other restrictions.  The “Employee Injury Report” completed on February 29, 2000, indicates that the “Employee alleges he felt pain in lower back while breaking down a pallet of meat,” and the diagram on that report locates the pain in the waist area, just above the hips.  The employee’s pain continued, and on March 1, 2000, still diagnosing acute lower back pain, Dr. Heubner increased the employee’s medications and prescribed six sessions of physical therapy.  The physical therapist’s initial evaluation on that same date indicates that the employee was reporting current symptoms of “[c]entralized bilateral lumbar pain and a complaint of knotting in the upper back,” with the pain tending “to shoot down the right lower extremity with twisting activities.”  Physical therapy notes for March 6, 2000, note and diagram pain in both the lumbar and thoracic regions of the employee’s back.  Notes on at least one of the employee’s succeeding sessions also reference thoracic pain, and on March 15, 2000, Dr. Heubner acknowledged “some spasms in the thoracic region of his back,” although her working diagnosis remained lumbar strain.

On March 29, 2000, on the employee’s complaints of pain in his right buttock and right thigh but noting no obvious spasms on exam, Dr. Heubner referred the employee for chiropractic treatment, still under a diagnosis of lumbar strain, with no mention of any thoracic symptoms.  On March 30, 2000, the employee commenced treatment with chiropractor Dr. Jason Eggers at the Institute for Athletic Medicine, to whom he complained of bilateral hip pain after initial but now substantially dissipated low back pain following his February 20, 2000, work injury, but “[n]o additional symptoms.”  Upon follow-up examination on April 28, 2000, Dr. Heubner continued to diagnose “[l]umbar strain” and again referenced no specifically thoracic symptoms, although she did on that date and again two weeks later reference generally the employee’s complaints of some “knots in his back.”  On May 4, 2000, the employee reported to Dr. Eggers “substantial improvement in the hips, but now . . . some upper back and shoulder pain.”

On June 15, 2000, the employee was examined by orthopedist Dr. Glen Butterman at the Midwest Spine Institute, to whom he complained of low back and bilateral hip pain, into his right buttock and leg to the foot and in his left buttock and leg to his knee.  Dr. Butterman diagnosed a posterior annular tear of a lumbar disc, based on the employee’s history, and prescribed medications and an isometric strengthening program.  On August 9, 2000, the employee underwent a lumbar MRI scan, which was read to reveal a moderate two-level lumbar disc degeneration and central posterior annular tears and posterior disc bulging at both L5-S1 and L4-5, with no apparent associated disc herniation, stenosis, or nerve root impingement and no spondylolysis, facet arthropathy, or spondylolisthesis.  When the employee returned to see Dr. Butterman on August 24, 2000, Dr. Butterman recommended a health club membership.  The employee evidently made some improvement in the months that followed, but  eventually, on December 14, 2000, under a now working diagnosis of degenerative disc disease from L4 to S1, Dr. Butterman began considering steroid injections and a functional capacities evaluation [FCE].

On February 8, 2001, Dr. Butterman recommended that the employee undergo an epidural steroid injection and a functional capacities evaluation.  The employee underwent the injection at L4-5 on February 19, 2001, and on February 28 and March 1, 2001, he underwent the recommended FCE, which resulted in restrictions apparently exceeded by full-duty work at his meat cutting job with the employer.  The employee nevertheless continued in accommodated work with the employer, however, and on May 3, 2001, he returned to see Dr. Butterman, complaining that his epidural steroid injection had resulted in only about three days’ relief.  Dr. Butterman prescribed chiropractic care and discussed surgical alternatives with the employee, recommending that he try to get by with light-duty work within his FCE restrictions and avoid surgery “if at all possible.”  When he saw Dr. Butterman again on July 16, 2001, the employee acknowledged some improvement in his low back pain but complained of continuing other problems, particularly a related difficulty sleeping and a recent knee injury.  Dr. Buttermann prescribed a trial of physiatry and rehabilitation at Physicians Neck and Back Clinic.

On July 25, 2001, the employee was examined by Dr. Alison Coulter at Physicians Neck and Back Clinic, to whom the employee complained of “low back pain which radiates into the right buttock” and also of “very very brief, but incredibly intense shock like pain down the right leg.”  In her report on that date, Dr. Coulter indicated that the employee “also complains that the back pain radiates up between the shoulder blades and can also be quite intense,” that “[t]his pain is more stubborn and usually will not improve until at least a day goes by,” with “increased pain in the middle back with any twisting type of motion.”  Dr. Coulter diagnosed mechanical low back pain, lumbar degenerative disc disease, and deconditioning syndrome, and she recommended a short-term, active rehabilitation program.  In follow-up on August 15, 2001, after seven rehabilitation sessions, Dr. Coulter indicated that objectively the employee was making “good progress,” although his “subjective pain in the back is slightly worse,” noting, however, that his subjective leg pain was improved and that there was decreased frequency of pain in the middle back.  On September 6, 2001, after twelve rehabilitation sessions with the employee, Dr. Coulter reported that the employee’s subjective pain in the back was again slightly worse, although the leg pain was again “greatly improved.”  On September 26, 2001, after eighteen rehab sessions with the employee, Dr. Coulter reported that, while “[o]bjectively, he is making good progress,” subjectively he continued to have “good and bad days.”  She indicated that she had

On October 8, 2001, Dr. Butterman modified the employee’s restrictions to permit him to do his normal job except for tasks that required twisting, noting that the employee’s manager was “fairly understanding of his back condition.”  On November 6, 2001, the employee was examined on referral from Dr. Butterman by Dr. Todd Hess at United Pain Center, to whom the employee complained of low back pain that would shoot down into his legs at times and sometimes up into his mid and upper back.  Upon examination, Dr. Hess assessed a “[l]ong-standing history of low back pain which appears to be a combination of discogenic and sacroiliac joint disease.”  When he followed up with Dr. Hess’s nurse practitioner Diane Bakdash on January 9, 2002, the employee complained of pain that sometimes radiated all the way to his ankles and that “also goes up his back to his shoulders at times.”  On a Health Care Provider Report dated January 21, 2002, Dr. Butterman indicated that the employee had reached maximum medical improvement [MMI] on January 7, 2002,^[1] with regard to his February 20, 2000, work injury, subject to a 10% whole-body impairment, pursuant to Minnesota Rules 5223.0390, subpart 3C(2), which rates permanent partial disability for a radiographically corroborated lumbar pain syndrome at multiple vertebral levels.   About this same time, early 2002, the employer advised the employee that it could no longer accommodate the restrictions established by the employee’s February/March 2001 FCE.

On September 18, 2002, the employee saw Dr. Hess again, “for ongoing discussion of his low back pain with a history of a work related injury.”  On that date, the employee reported that he had changed jobs, that he was back in school for retraining in marketing, and that his pain was “down quite a bit from last visit,” although he still had “[o]ngoing muscle spasm in the low back.”  There is no record of any specifically nonlumbar symptomology.  On September 22, 2002, the employee was examined in the Emergency Department at Unity Hospital regarding “some mild shortness of breath symptoms,” complaining to the attending physician that “when he starts thinking about his shortness of breath it seems to get worse rather than better.”  Chest x-rays were unremarkable, and the attending physician diagnosed “[s]omatic shortness of breath of unclear etiology, possibly musculoskeletal” and referred the employee to his primary care clinic.  On November 7, 2002, the employee indicated to Dr. Hess’s nurse practitioner Una Edwardson that his low back pain was under control but that there was now “a constant knot between the shoulder blades,” usually triggered by his back pain, “and that it radiates upward to the base of his neck.”  On December 6, 2002, the employee was treated at Ham Lake Physical Therapy, where he reported “a history of low back pain and mid-thoracic pain for approximately 15 years.”

Beginning on February 5, 2003, and for about two years thereafter, the employee saw Dr. Hess on over two dozen occasions, for complaints that initially included and eventually - - by about October of 2003 - - came to focus on thoracic pain.  The employee’s treatment during that period came to include various medical and therapeutic modalities, including thoracic transforaminal steroid injections and trigger-point injections, none of which provided any lasting relief.  In November of 2003 the employee underwent an MRI scan of his thoracic spine, which Dr. Hess reported on December 10, 2003, to have revealed a central disc protrusion at T7-8, abutting the thecal sac but not effacing it, and another disc protrusion at T8-9, with a mild degree of anterior spinal cord effacement.  On February 19, 2004, in response to recurrent chest pain and shortness of breath, the employee underwent repeat x-rays of his chest, which again proved unremarkable.

The employee subsequently underwent a one-day FCE to determine his ability to return to a meat cutter position at the employer.  In her report to Dr. Hess on April 14, 2004, the occupational therapist conducting the evaluation, Jessica Ogren, indicated her conclusion that the employee was “capable of performing physical work at the Heavy level,” although “a position in a Medium level work environment with occasional Heavy level requirements would be the most appropriate given [the employee’s] history and present diagnoses.”  Ms. Ogren went on to conclude that, “[a]ccording to a job description provided by Cub Foods, [the employee] would be a job match at this recommended work level to the meat cutter position” and was “capable of returning full-time without restrictions.”^[2]  The employee apparently opted instead, however, to complete his studies in marketing.

On July 12, 2004, the employee elected to forego any further injections, the last epidural having actually made him feel worse.  On August 12, 2004, he was examined by Dr. Buttermann’s physician’s assistant, Eric Salman, regarding complaints of midback pain and right anterior rib pain.  Upon review of the employee’s MRI scan, Mr. Salman diagnosed midback pain with T7-8 disc herniation (sic), together with “[r]ight upper quadrant / rib pain of undetermined etiology,” and referred the employee for further evaluation of his shortness of breath symptoms.  In a report on a follow-up telephone conference with the employee on August 24, 2004, Mr. Salman indicated that the employee’s disc herniation was at the opposite side of his chest from his chest symptoms.  He indicated that Dr. Butterman had suggested certain diagnostic tests that the employee might try, but he indicated further that workers’ compensation was unlikely to cover the cost of these tests.  On September 13, 2004, an award was evidently filed on a stipulation for settlement by the parties, there having also been a prior settlement, with medical benefits left open.^[3]  Later that month, on September 22, 2004, on referral from the employee’s family physician, Dr. Keith Oelschlager, the employee underwent an abdominal ultrasound at St. Paul Radiology, in an effort to diagnose the source of some “[r]ight upper quadrant pain.”  The test was read to be normal.

The employee eventually completed his retraining and obtained his degree in marketing, and in January of 2005 he evidently began working at a temporary desk job with Caterpillar.  The employee’s complaints of spasm in his mid back began to increase upon assuming this employment, and on June 3, 2005, he filed a medical request, seeking payment for his treatment and prescriptions at United Pain Center.  On June 23, 2005, the employer and insurer denied the employee’s request, on grounds that it was insufficiently documented.

On July 9, 2005, the employee was examined for the employer and insurer by psychopharmacologist/neurologist Dr. Donald Starzinski.  In his report on July 20, 2005, Dr. Starzinski diagnosed “multifocal musculoskeletal pain, prominently involving the lumbar and thoracic spine,” concluding in part that the employee “does not have any significant findings either by examination or radiographic studies to suggest radiculopathy.”  He suggested instead that the employee’s condition was “related to degenerative osteoarthritis, which,” he added, “in my opinion, was substantially contributed to by his many years of heavy work as a meat cutter.”  Dr. Starzinski opined that “elements of [the employee’s] pharmacologic management are reasonable, although, others are quite suboptimal and may actually be counterproductive,” specifically referencing “the use of the narcotic analgesic agent Dilaudid on a longstanding basis as inadvisable in the context of this chronic pain condition.”  Dr. Starzinski went on also to state,

Also on July 20, 2005, Dr. Hess wrote to the employee’s attorney, in reply to various queries regarding principally the employee’s medication.  In his letter, Dr. Hess indicated that the employee’s medications were “directly related to [the employee’s] workers’ compensation injury,” that the employee was using his pain medication “only as needed for pain management,” that “[h]e uses it at low doses . . . and stays well within the parameters we have written for him,” and that he, Dr. Hess, had “no concerns of [the employee] over-using his medications, actually he under-utilizes his medications.”  When he saw the employee again on July 22, 2005, Dr. Hess noted that he was “very pleased with [the employee’s] motivation and his can-do attitude,” notwithstanding the fact that his thoracic “muscle spasm really does continue to look quite bad.”  Dr. Hess went on to note that “[u]nfortunately, there are Workman’s Compensation issues remaining problematic with not paying for things” and that “[t]his still is absolutely related to his work-related injury, so I am really unsure as to why the payment is not there.”

In about August of 2005, the employee was laid off from his job with Caterpillar.  About the same time, on August 15, 2005, the employee’s medical request came on for consideration at an administrative conference, and a decision granting the employee’s request was filed on December 14, 2005.  Also in December of that year, notwithstanding continuing and reportedly palpable thoracic back spasms, the employee opened his own smoked meat shop, and on January 10, 2006, he underwent Botox injection treatment for thoracic myofascial pain syndrome.  On January 13, 2006, the employer and insurer filed a request for formal hearing, contending that the employee’s treatment fell outside the treatment parameters and was not reasonable and necessary.  The employee filed another medical request on January 23, 2006, seeking prior approval of additional trigger point injections, and on January 27, 2006, the employer and insurer denied that request.  On February 9, 2006, the employer and insurer’s request for formal hearing and the employee’s employee’s medical request were consolidated for hearing.

On February 21, 2006, the employee saw Dr. Hess again on an emergency basis, reporting that he was “not doing well at all” and that his pain from thoracic muscle spasm was continuing to increase, notwithstanding his Botox injection.  Assessing in part “significant myofascial pain and thoracic pain” and “[s]ignificant increased stress and anxiety over new business” in the course of “actively weaning himself off the opioids,” Dr. Hess increased the employee’s prescription for Valium and commenced treatment with the sleep aid Ambien.

On February 22, 2006, Dr. Starzinski testified by deposition, essentially reiterating conclusions that he had expressed in his report of July 20, 2005, but indicating that he no longer considered the employee’s thoracic problems to be related to the February 20, 2000, work injury, given their current severity and their remoteness from the original injury.  He testified that “[t]here is not a good correlation even as far as the symptoms go, so I would say I would tend to not relate . . . [the employee’s] particular work activities to the appearance of the thoracic spine symptoms.”  The doctor was informed at the deposition that the employee had fallen on his right shoulder in May of 1994, and he agreed that the appearance of thoracic symptoms in 2003 was possibly a consequence of that fall perhaps precipitated by postural requirements of the employee’s studies in marketing.  When asked near the end of his testimony if, given the employee’s termination from the employer on February 27, 2002, a plan to treat the employee’s thoracic back initiated in November 2002 would be reasonable and necessary treatment for his 1999 and 2000 work injuries, Dr. Starzinski replied, “No, because it’s not close enough as far as it[]s temporal relationship.”

On February 27, 2006, the employee was seen at and discharged from the emergency room at HealthEast St. John’s Hospital, for what was described simply as a “Breathing Problem.”  When he saw Dr. Hess again on March 1, 2006, the employee appeared to be in substantial distress over pain from his thoracic muscle spasm, and Dr. Hess ordered an MRI scan.  The scan, conducted that same day, was read to reveal mild, scattered thoracic disc degenerative changes, together with a small shallow disc herniation on the left at T8-9, apparently unchanged since November 2003.  On March 7, 2006, the employee saw Dr. Angelito Sajor at United Pain Center in consultation for a possible thoracic epidural steroid injection.  Noting that the employee was currently taking three medications^[4] and had previously tried twelve different medications,^[5] Dr. Sajor emphasized to the employee the failure of past injections to bring him any significant relief, and the employee elected not to proceed with the injections.  Nevertheless, on March 16, 2006, the employee returned to United Pain Center, where he requested and was given an epidural steroid injection by Dr. Stephen Wagner, who stated in his notes, “I think unless there is some lasting benefit, I would discourage further interventions of this nature.”

On March 23, 2006, the employee was examined at the Columbia Park Medical Group on referral for breathing problems associated with his thoracic spine.  On that same date, he was examined once again by Dr. Buttermann, who, without asserting a specific causation opinion, opened his consultation notes, “The [employee] had a work injury.  He has thoracic and lumbar conditions.  His lumbar pain is overall stable.  His thoracic back pain is still problematic.”  Dr. Buttermann found the recent thoracic MRI scan “really quite poor” in quality, but, finding evidence on it of a possible eventual need for thoracic fusion surgery, he anticipated a need for a repeat MRI scan and prescribed a TLSO thoracic brace for preoperative pain control and possible postoperative stabilization.  The employee was fitted with such a brace on March 29, 2006, by Tillges Certified Orthotic Prosthetic, Inc.  On April 5, 2006, the employee returned to United Pain Center with continuing complaints of mid-thoracic muscle spasm, and nurse practitioner Edwardson referred him for a rheumatological evaluation and for counseling with a pain psychologist, who subsequently found him to be moderately depressed.

On June 2, 2006, the employee was seen by rheumatologist Dr. Martha Grandits, on referral from Dr. Butterman, with renewed complaints of shortness of breath.  In her notes, Dr. Grandits indicated that the employee reported to her “that he does not have pain per se in the thoracic spine but he just feels short of breath or like he is not able to expand his chest,” although he had “no painful breathing.”  Dr. Grandits concluded, “I do not appreciate, by this gentleman’s history or on exam, any indication of an inflammatory back disease” or loss of range of motion, notwithstanding his history of “back pain for 17 years.”

On July 19, 2006, Dr. Hess testified by deposition, in part that, when he first saw the employee in November of 2001, his diagnosis was of low back pain and muscle spasm, due to a combination of discogenic and SI joint issues.  Dr. Hess testified that his initial focus had been on the employee’s low back problem because of his “significant SI joint dysfunction which a lot of people miss” but that, as that problem improved, one of the bigger problems was his thoracic spasm, “and that was found relatively early on in his care.”  Dr. Hess testified expressly that he believed that the treatment that he had provided to the employee had been causally related to the employee’s work injuries of February 1, 1999, and February 20, 2000.  It was also his testimony that “from a legal standpoint [the employee]’s at MMI,” although “[m]y hope is with continued therapy, strengthening, he’ll get better.”  Dr. Hess acknowledged that the employee was currently being medicated with the strong narcotic Dilaudid, but he insisted that the employee was not abusing his medication and indeed had been reluctant to take as much as the doctor had recommended for fear of addiction.  He testified also that trigger point injections would probably not lead to a cure for the employee but that thoracic epidural injections would probably continue to be part of his therapy, in order to avoid surgery.

The matter came on for hearing on September 13, 2006, on which date the employee was continuing to complain of ongoing thoracic spine pain.  Benefits at issue at the hearing were $19,027.96 in medical treatment expenses, including $6,075.40 for the employee’s Botox injection on January 10, 2006, $2,531.10 for his MRI scan on March 1, 2006, and $1,712.50 for his trigger-point injection on March 16, 2006.^[6]  The employee’s attorney asserted at hearing that there were really only two charges at issue that appeared to predate July 20, 2005, the date of Dr. Starzinski’s IME report - - one on February 19, 2004, evidently for emergency doctor care, and one on July 8, 2004, for unspecified treatment, both of which the attorney characterized as “not very significant.”^[7]  The employer and insurer stipulated at hearing to liability for work injuries on both February 1, 1999, and February 20, 2000, but only to the lumbar spine, and to the reasonableness and necessity of all treatment at United Pain Center up to July 20, 2005.  Specific issues at hearing included the following:  (1) whether the employee had sustained a work-related injury to his thoracic spine on February 1, 1999, and/or February 20, 2000; (2) whether the medical treatment at issue was reasonable and necessary; (3) whether the seven intervenors - - St. Paul Radiology, Medica Health Plans/Ingenix, Associates Anesthesiologists/PMSI, Allina Medical Clinic, United Hospital, Tillges Certified Orthotic Prosthetic, Inc., and Midwest Spine Institute - - were entitled to reimbursement and/or payment for medical expenses incurred; and (4) whether the Minnesota treatment parameters applied, given the employer and insurer’s denial of liability for a thoracic injury, and whether the employee’s Botox injection on January 10, 2006, was precluded by those parameters.

By findings and order filed October 20, 2006, the compensation judge concluded at Findings 1 and 2 that the employee had not proven that he sustained an injury to his thoracic spine either on February 1, 1999, or on February 20, 2000.  Further, in reliance on the opinions of Dr. Starzinski rather than on those of Dr. Hess, the judge concluded at Finding 5 that “treatment at United Hospital, Associated Anesthesiologists/PMSI, and United Pain & Internal Medicine subsequent to July 20, 2005 is excessive and unreasonable considering the high cost, relatively short duration of relief of pain, and limited extent of relief of pain.”  With regard to the opinions of Dr. Starzinski, the judge noted in her memorandum that “Dr. Starzinski originally understood the February 20, 2000 work injury involved a fall on the back, a history not confirmed by the testimony of the employee or the medical records.”  The judge explained in a footnote that, “since the February 20, 2000, work injury does not involve a fall on the back, the [original] opinion of Dr. Starzinski relating a thoracic injury to the work injury is not persuasive.”  The judge went on then to quote from Dr. Starzinski’s deposition testimony that “[t]here is not a good correlation even as far as the symptoms go, so I would say I would tend to not relate . . . [the employee’s] particular work activities to the appearance of the thoracic spine symptoms.”  On those grounds the judge denied all of the employee’s claims for payment and reimbursement of medical expenses, concluding also that, because the employer and insurer had denied primary liability for an injury to the employee’s thoracic spine, the treatment parameters did not apply to the employee’s claim.  The employee appeals.

In reviewing cases 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 (1992).  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, “[f]actfindings are clearly erroneous only if the reviewing court on the entire evidence is left with a definite and firm conviction that a mistake has been committed.”  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).  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.”  Id.

Having indicated that the parties had stipulated to the occurrence of lumbar injuries on both February 1, 1999, and February 20, 2000, the compensation judge concluded at Findings 1 and 2 that the employee had failed to prove an injury to his thoracic spine on either of his injury dates.  Accordingly, the judge concluded at Findings 4, 7, and 10 that the employee’s work injuries were not a substantial contributing factor in the employee’s treatment for breathing problems at St. Paul Radiology, at HealthEast St. John’s Hospital, and at Columbia Park Medical Group or in the cost of the thoracic TLSO brace from Tillges Certified Orthotic Prosthetic, Inc.  At Findings 6, 8, and 9, the judge concluded further that the employee had also not proven that his lumbar work injuries were substantially related to his prescription for the sleep agent Ambien purchased at Cub Foods Pharmacy on April 19, 2006, to his medical expenses at Midwest Spine Institute due to a “lack of itemization in the medical bill,” or to medical expenses paid by Medica Health Plans/Ingenix.  The employee contends that the judge’s decision was clearly erroneous and unsupported by substantial evidence, in that it “lacked adequate foundation and ignored the substantial evidence in the record that supported the Employee’s claim.”  We are not persuaded.

We reiterate initially that it is not the job of this court to assess whether there may have been substantial evidence in the record to support a factual conclusion contrary to that reached by the compensation judge; this court’s function on factual review is only to assess whether there exists substantial evidence in the record to support the conclusion reached by the judge.  See Land v. Washington County Sheriff’s Dep’t, slip op. (W.C.C.A. Dec. 23, 2003); see also Ludford v. Honeywell, Inc., slip op. (W.C.C.A. Mar. 17, 2004); Moe v. Dr. Matthew A. Gahn, slip op. (W.C.C.A. Dec. 31, 2003).  Nor does there appear to have been inadequate “foundation” for the medical opinion of Dr. Starzinski, upon which the judge relied.  We will presume that by “adequate foundation” the employee means substantial evidentiary support and that the operative issue in this appeal is whether or not there is substantial evidence in the record to support the compensation judge’s conclusion that the employee did not sustain an injury to his thoracic spine either concurrent with or consequential to either of his admitted lumbar work injuries.

On September 22, 2004, and February 27, March 23, and March 29, 2006, the employee was treated at, respectively, St. Paul Radiology, HealthEast St. John’s Hospital, Columbia Park Medical Group, and Tillges Certified Orthotic Prosthetic, Inc., for what appeared to be breathing problems, and there was some conjecture that these symptoms were related to cramping that the employee was experiencing in his upper back.  The compensation judge concluded that neither that cramping nor any other thoracic symptomology was related to the employee’s 1999 and/or 2000 work injuries, and we find substantial evidence to support that conclusion.

We find no specific medical or other evidence that there were any immediate or delayed thoracic consequences to the employee’s February 1, 1999, work injury.  We concede that certain upper back symptoms were mentioned in the employee’s physical therapy records shortly after his February 20, 2000, work injury and that Dr. Hess was clearly of the opinion that the employee’s thoracic condition related to that injury.  However, those upper back symptoms appear to have subsided almost entirely after about a month, and, to the extent that they may have reappeared intermittently over the course of the next three years, they were associated by the employee in December 2002 with a condition that he had been experiencing “for approximately 15 years.”  Moreover, they were frequently related to specifically shoulder problems–problems that predated at least the employee’s February 2000 work injury and that apparently did not appear significant in an MRI post-dating his February 1999 work injury.  Meanwhile, the employee’s working diagnosis by medical experts remained all the while focused only on his lumbar back.  Not until late 2002, nearly three years after the second work injury, did his thoracic symptoms come to be acknowledged in any diagnosis by medical experts, the lumbar symptoms that had been the immediate focus of the injury becoming virtually overshadowed by the thoracic symptoms in 2003.  We acknowledge that Dr. Starzinski, in his initial report on July 20, 2005, did relate the thoracic symptoms to the employee’s 2000 work injury, but this was based on an evidently false presumption that the employee had fallen on his back in the process of his injury.  Generally speaking, a medical expert’s opinion is warranting of deference only so long as it is based on accurate factual premises, see Nord v. City of Cook, 360 N.W.2d 337, 342-43, 37 W.C.D. 364, 372-73 (Minn. 1985) ("the trier of fact's choice between experts whose testimony conflicts is usually upheld [unless] the facts assumed by the expert in rendering his opinion are not supported by the evidence"), and it was not unreasonable for the compensation judge to dismiss that earlier causation opinion of Dr. Starzinski on that basis.  In his deposition testimony subsequently, it is no longer evident that Dr. Starzinski presumed a fall as an element of the mechanism of the employee’s injury, and it was not unreasonable for the compensation judge to find credible and to rely upon the doctor’s later opinion that the appearance of employee’s thoracic symptoms was too remote from the injury as he now understood it to be causally related to that injury.  Id.; Brennan v. Joseph G. Brennan, M.D., 425 N.W.2d 837, 839-40, 41 W.C.D. 79, 82 (Minn. 1988) (assessment of a witness's credibility is the unique function of the trier of fact), citing Spillman v. Morey Fish Co., 270 N.W.2d 781, 31 W.C.D. 187 (Minn. 1978).

At Finding 6, the compensation judge concluded that the employee’s work injuries “have not been proven” to be a substantial contributing factor in the need for obtaining the sleep aid Ambien on April 19, 2006.  Because most of the symptoms compelling Dr. Hess’s prescription of Ambien at that time appear to have been thoracic symptoms, which we have affirmed as being unrelated to the employee’s work injuries, and because the employee has offered no persuasive argument that they were not, we cannot conclude that it was unreasonable for the compensation judge to deny payment for the medication as she did.  At Finding 8, the judge denied also the employee’s medical expenses at Midwest Spine Institute for apparently similar reasons - - “[b]ased upon the lack of itemization in the medical bill,” and we must conclude that that conclusion of the judge is also not unreasonable.  Finally, at Finding 9, the judge found all expenses paid by Medica Health Plans/Ingenix similarly unrelated to the employee’s work injuries.  While the employee did appeal nominally from this finding of the judge, nowhere in either his appellate brief or his reply brief - - or even his testimony - - does the employee even make any reference to that intervenor, and we might only speculate as to what might be the basis of its interest in the case.  The judge apparently accepted the $3,598.21 figure, proposed in the “Summary of Claim” accompanying the employee’s exhibits, as the amount of expenses paid for by Medica Health Plans/Ingenix, but, based on the record before us and the absence of specific arguments of the employee on appeal, we cannot find unreasonable the judge’s conclusion that the employee’s lumbar work injuries were not proven to be a substantial contributing factor in those expenses.  See Minn. R. 9800.0900, subp. 1 (“Issues raised in the notice of appeal but not addressed in the brief shall be deemed waived and will not be decided by the court.”).  Because it was not unreasonable, we affirm the compensation judge’s conclusion that the employee’s work injuries were not a substantial contributing factor in the specific medical benefits at issue in Findings 4, 6, 7, 8, 9, and 10.  See Hengemuhle, 358 N.W.2d at 59, 37 W.C.D. at 239.

At Finding 5 of her findings and order and on page 5 of her memorandum, the compensation judge also concluded that all of the employee’s treatment at United Hospital, at Associated Anesthesiologists/PMSI, and at Allina Medical Clinic’s United Pain & Internal Medicine clinic subsequent to July 20, 2005, was not reasonable and necessary, concluding in that finding that it was specifically “excessive and unreasonable, considering the high cost, relatively short duration of relief of pain, and limited extent of relief of pain.”  The judge implied in that finding that some of the post-July 20, 2005, treatment at United Pain & Internal Medicine may have been treatment for the employee’s lumbar spine injury, for which the employer and insurer had admitted liability, but she indicated that even that lumbar treatment, after July 20, 2005, had been “excessive and unreasonable considering the high cost, frequency of treatment, [and] limited duration of relief from the treatment.”  Although he appealed nominally from Finding 5 in his notice of appeal, the employee materially briefed only the general issue of the claimed medical expenses’ causal relationship to his February 1999 and February 2000 work injuries.  As the employer and insurer have noted, the employee did not brief the issue of any treatment’s necessity under the specific circumstances of the employee’s specific lumbar condition, nor did he brief the issue of the reasonableness of any treatment’s cost in light of its anticipated effect.^[8]  Aside from noting that the judge’s decision on this issue is amply supported by the expert medical opinion of Dr. Starzinski, we will not, therefore, address the judge’s denial of payment for treatment at any of these three facilities after July 20, 2005.  See Minn. R. 9800.0900, subp. 1 (“[i]ssues raised in the notice of appeal but not addressed in the brief shall be deemed waived and will not be decided by the court”).  Accordingly, that denial is affirmed.