The employer and insurer appeal from the compensation judge’s finding that the employee’s work injury substantially contributed to the employee’s need for medical treatment and surgery.  We affirm.

The claim arises from an admitted work-related injury that Frank Schweder, the employee, sustained to his low back on or about April 28, 2006, while working for Covalence Specialty Materials, the employer.  He earlier had provided computer customer support, and, at the time of his injury, his job included receiving, inspecting and installing computers in the employer’s facility.  On April 27, 2006, the employee felt a sharp pain in the middle of his low back while stacking boxes of computers onto a cart.  He sought treatment at the Park Nicollet Urgent Care Clinic the following day, reporting an increased amount of pain after lifting boxes at work the previous day.  He also consulted Dr. Kari Miller at Park Nicollet Clinic, again reporting a twinge or pain on the right side of his low back that had worsened since the previous day.^[1]  Dr. Miller diagnosed a right-sided lower back strain; she prescribed medication and recommended exercises, heat and ice treatment.  The employee returned to work at his same job, but one week later on May 5, 2006, he again sought treatment at Park Nicollet Clinic, reporting sharp pain in the right side of his back during the past week.  An x-ray taken on that date showed mild disc space narrowing from L2-L4 and lower lumbar facet arthropathy from L4-S1 bilaterally.  Dr. Michael Pischke diagnosed a lumbar sprain, and recommended work restrictions through May 19, 2006.  He also noted that the employee was scheduled to begin physical therapy on May 10, although the evidence does not contain any records of physical therapy provided in 2006.

The employee had sought medical treatment for low back symptoms prior to this injury.  Records show that on May 17, 2002, he consulted Hibbing Family Medicine Center, complaining of back pain resulting from bending over while working at home.  Dr. Mitch Cardwell diagnosed him with an acute low back strain and recommended conservative treatment.  The next reference to medical treatment was on January 28, 2003, when the employee reported to Park Nicollet Clinic, complaining of left buttock pain radiating down to his left leg during the past three to four days.  He was diagnosed with sciatica, was referred to physical therapy, and was advised to make a follow-up appointment with the family practice department.  On January 29, 2003, Dr. Craig Malvey examined the employee, evidently both for his low back symptoms and for other medical conditions.  The employee reported aching discomfort in his low back with radiation down to his left thigh and knee.  Dr. Malvey noted no numbness, paresthesias, or weakness, and diagnosed an acute low back strain.  He recommended physical therapy and follow-up treatment if the employee’s symptoms did not improve.^[2]

The employee did not seek any further medical treatment between January 2003 and April 2006.  After his initial treatment in April and May 2006, the employee had another gap in his medical treatment between May 2006 and May 2007.  On May 9, 2007, the employee consulted Dr. Fereshteh Kaveh at Park Nicollet Clinic, reporting that his pain had worsened and had extended into both legs, worse on the left side.  He also experienced some numbness in his feet after sitting.  Dr. Kaveh diagnosed the employee with low back pain and possible sciatica, recommended over-the-counter anti-inflammatory medication, and also prescribed Percocet and a Medrol Dosepak.  By mid-May, his symptoms persisted and so the employee returned to Dr. Malvey, whom he had consulted at Park Nicollet for low back symptoms he experienced in January 2003.  The employee reported low back and leg pain during the past month.  He recalled no specific trauma other than an onset of pain near the time he did some vacuuming at home.  Dr. Malvey referred the employee for a physical therapy evaluation and prescribed pain medication.  An MRI of the employee’s lumbar spine taken on May 22, 2007, revealed a broad-based disc bulge at the L3-4 and L4-5 levels in addition to narrowing of the neural foramen, which correlated with the employee’s radicular symptoms.  A contrast dye-enhanced MRI scan confirmed those findings.

The employee continued to follow up with Dr. Malvey.  He underwent seven physical therapy visits, which the employee reported had improved but had not resolved his symptoms.  Dr. Malvey prescribed Vicodin and referred the employee for an epidural steroid injection.  The employee was also referred to Dr. Daniel Kurtti of the Physical Medicine and Rehabilitation Clinic at Park Nicollet, who in turn diagnosed lumbar spine degenerative disease, lumbar facet degenerative joint disease, L4-5 spinal spondylosis, low back pain and chronic pain syndrome.  Dr. Kurtti referred the employee to the Medical Advanced Pain Specialists [MAPS] pain clinic, where he was evaluated in October 2007 by Dr. David Schultz and CNP Mary Esslinger. They referred the employee for a series of diagnostic and therapeutic lumbar epidural steroid injections and physical therapy, and prescribed pain medications.  The employee underwent at least three epidural steroid injections, and later underwent a series of lumbar medial branch blocks.  The employee continued his treatment at MAPS and, in March 2008, underwent radiofrequency neuroablation of lumbar medial branch nerves at the L3-4 and L4-5 levels.  His lower back pain persisted and, in May 2008, he underwent lumbar discography.  Upon review of the discography findings, Dr. Schultz determined that the employee was not a good surgical candidate and that he should consider an implanted device for pain control.  Following an evaluation in June 2008, Dr. Schultz recommended that the employee undergo an implantation of a spinal cord stimulator.

In late May 2008, the employee moved to northern Minnesota in order to live near family members who could assist him with caring for his daughter and two grandchildren.  He therefore continued his medical treatment with a physician in the Virginia, Minnesota, area upon referral from his Park Nicollet physician.  Dr. T. Scott Douglass, of the Virginia Occupational Medicine Department of the Duluth Clinic, examined the employee in mid-December 2008, at which time the employee reported continued lower back pain with radiation into his legs that limited his standing and walking and was relieved by lying down or sitting.  The employee underwent additional diagnostic testing, including an EMG in January 2009 and a CT myelogram in February 2009.  Upon review of those tests, Dr. Douglass diagnosed “[m]oderate to moderately severe lumbar spinal stenosis at the L3-L4 and L4-L5 levels bilaterally with symptoms suggesting pseudoclaudication.”  He concluded that, in view of the employee’s “failure to respond to extensive conservative therapy in the past,” the employee should undergo a surgical consultation.

At the referral of Dr. Douglass, the employee was examined by Dr. Timothy Garvey at the Twin Cities Spine Center on April 9, 2009.  Dr. Garvey recommended an L2-L5 decompression with discectomy at the L2-3 and L3-4 levels.  The employee sought authorization from the insurer for the recommended surgery.

The employer and its insurer, Arch Insurance Group, requested that the employee undergo an independent medical examination with Dr. Terry Hood, in part to assess the employee’s claim for surgery. Following his examination on June 13, 2009, Dr. Hood diagnosed degenerative disc disease of the lumbar spine with congenital stenosis.  In his opinion, the employee’s April 28, 2006, incident did not represent a significant contributing factor in the employee’s low back condition.  In Dr. Hood’s opinion, that injury was, at most, a temporary exacerbation of a pre-existing lumbar spine condition.  Dr. Hood recommended work restrictions.  He also concluded that the recommended surgery would be reasonable and necessary treatment but that neither the employee’s restrictions nor his need for surgery were related to his 2006 injury.  Instead, Dr. Hood concluded that the employee may have required conservative therapy for his temporary aggravation for approximately one month following his claimed 2006 work injury, but that he had reached maximum medical improvement (MMI) within one month of his injury and any further treatment was unrelated to his work injury.

The employee filed medical requests on July 8, 2009, and August 14, 2009, requesting approval and/or payment for medical treatment and surgery.  The employer and insurer denied liability for the ongoing medical treatment, relying on Dr. Hood’s opinion that such treatment was not causally related to the employee’s April 2006 injury.  The employee continued to follow-up with Dr. Douglass while awaiting surgery.  In a report dated September 3, 2009, Dr. Douglass provided his opinion that the employee’s work injury of April 28, 2006, was a substantial contributing cause of his need for ongoing medical treatment, including the surgery recommended by Dr. Garvey.

On September 8, 2009, the employee underwent surgery, performed by Dr. Garvey.  That surgery involved a complete bilateral laminectomy at L3 and L4 levels, a left hemilaminectomy at the L5 level, and bilateral hemilaminectomy at the L2, with decompression of the lateral recess of the L2-3, L3-4, and L4-5, and discectomy at the L3-4 and L2-3 levels.  The employee testified that this surgery improved his symptoms.  Even though he continued to note low back pain, he no longer experienced leg pain or numbness in his feet nor the same type of severe low back pain he had earlier felt.

The employee’s medical requests were addressed at an evidentiary hearing on September 30, 2009.  In his Findings and Order served and filed November 25, 2009, the compensation judge concluded that the employee’s work injury of April 28, 2006, was a substantial contributing factor in the employee’s need for the disputed medical treatment, including surgery to his low back.  The compensation judge ordered payment of the associated medical expenses as well as reimbursement to the employee for mileage expenses incurred for medical treatment.  The employer and insurer appeal.

The employer and insurer appeal from the compensation judge’s determination that the employee’s need for medical treatment since April 2006, including his surgery in 2009, was causally related to his 2006 work injury.

The record contains conflicting medical opinions concerning the causation of employee’s low back condition and therefore the ongoing need for medical treatment to his low back.  Drs. Douglass, Garvey, and Hood concur that the employee’s diagnosis includes severe lumbar spinal stenosis at the L3-L4 and L4-L5 levels, degenerative disc disease, and disc bulging or protrusion at the L3-4 levels.  They disagree, however, on the effects of the employee’s 2006 injury.  As outlined in his report of September 3, 2009, Dr. Douglass concluded that the employee’s work injury of April 28, 2006, “was a substantial contributing factor in the need for ongoing medical treatment including the surgical treatment recommended by Dr. Timothy Garvey.”  By contrast, Dr. Hood concluded that the employee’s work injury in 2006 represented a temporary exacerbation of his underlying condition.  He cited to the low back symptoms reported by the employee as early as January 2003, and to the findings on the 2007 MRI scan that demonstrated a slowly progressive spine condition and “changes that would have taken years to develop.”  The record contains no causation opinion by Dr. Garvey, the employee’s treating surgeon.

The compensation judge chose Dr. Douglass’s opinion over that of Dr. Hood.  The employer and insurer argue that the record contains no substantive evidence that the 2006 injury caused, aggravated, or accelerated the employee’s preexisting condition.  The employer and insurer also argue that Dr. Douglass’s opinion, which was the sole medical opinion on which the judge relied, lacked foundation.  The employer and insurer argue that the September 3, 2009, narrative report of Dr. Douglass merely stated that the employee related his pain to a work injury on April 28, 2006, and that a recitation of the employee’s medical history did not equate to an opinion rendered to a reasonable degree of medical certainty.  They also argue that Dr. Douglass's statement, that the employee was “lifting something and felt pain in his back,” indicated that he was unaware of the circumstances of the work injury, and that he could not reasonably conclude, to a degree of medical certainty, “that an event caused [the employee’s] condition without knowing or remembering what was involved in such an event.”

The employer and insurer also argue that Dr. Douglass’s opinion is not corroborated by the contemporaneous medical records, that his opinion is conclusory in nature and lacks foundation, that he did not provide any rationale for his conclusion that the condition was caused or substantially aggravated by the employee's work injury.  They also argue that Dr. Hood’s opinion is the only one based on adequate foundation.

We cannot say that the compensation judge erred in relying on Dr. Douglass’s opinion and in concluding that the medical treatment was compensable.  In rendering his opinion on the causal relationship between the employee’s 2006 injury and his need for medical treatment and surgery, the compensation judge accepted the opinion provided by Dr. Douglass, and rejected the opinion provided by Dr. Hood.  The judge reviewed the various medical records and opinions, and concluded that the employee’s testimony and Dr. Douglass’s opinion were “amply corroborated” by the employee’s medical records.  Dr. Douglass first examined the employee in December 2008.  He took a history from the employee, recorded in his chart notes, which included the employee’s report that he had hurt his back by lifting computers.  According to his narrative report, Dr. Douglass also reviewed medical records from the Hibbing Family Medical Center and Park Nicollet Clinic, as well as the transcript from the employee’s deposition and Dr. Hood’s report.  These factors all establish his competence to render an expert medical opinion.  See Branstad v. Fedex Freight East, No. WC08-263 (W.C.C.A. June 11, 2009) (citing Grunst v. Immanuel-St. Joseph Hosp., 424 N.W. 2d 66, 40 W.C.D. 1130, (Minn. 1988); Karakash v. Superior Rock Bit Co., slip op. (W.C.C.A. May 3, 2001)).  The compensation judge accepted Dr. Douglass’s opinion that the employee’s 2006 work injury substantially contributed to his low back condition and need for surgery.  Dr. Douglass’s opinion had adequate foundation and so the judge could reasonably rely on it.

The compensation judge also explained his rationale for rejecting the opinion provided by Dr. Hood, as follows:

The employer and insurer also argue that the compensation judge misunderstood or ignored the documented history and contemporaneous medical records.  The compensation judge’s memorandum states that the employee continued to work from 2006-2007 with continuing back pain. Although the employee testified to this, his medical record on May 9, 2007, states that the employee reported his low back pain started about one week earlier.  On May 17, 2007, the employee reported about a one-month history of low back pain.  The employer and insurer argue that the record shows that the employee’s symptoms had subsided, and his later symptoms and condition commencing in 2007 had no relation to his work activity. In his memorandum, the compensation judge outlined medical treatment the employee received for his low back symptoms between May 2002 and January 2003.  He also outlined, in his findings and memorandum, the progression of symptoms the employee had experienced since his 2006 injury, and stated that he had “adopted the credible testimony of the employee” when concluding that the employee’s April 2006 injury substantially contributed to his need for the medical treatment at issue.  This court typically defers to a compensation judge’s judgment concerning the credibility of witness testimony.  See Krotzer v. Browning-Ferris/Woodlake Sanitation Serv., 459 N.W.2d 509, 513, 43 W.C.D. 254, 260-61 (Minn. 1990).

We are mindful that there is evidence in the record that supports the arguments presented by the employer and insurer.  The issue under this court's standard of review, however, is not whether the facts will support findings different from those made by the compensation judge, but, rather, whether substantial evidence supports the findings of the judge.  Land v. Washington County Sheriff’s Dep’t, slip op. (W.C.C.A. Dec. 23, 2003) (citations omitted).  Because the compensation judge’s decision is supported by substantial evidence in the record, including expert medical opinion, the employee’s medical records and the employee’s testimony, we conclude that substantial evidence supports the compensation judge’s findings that there is a causal connection between the employee’s April 28, 2006, low back injury and his current condition and need for the surgery that he underwent in 2009.  Accordingly, we affirm those findings.  See Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 549, 37 W.C.D. 235, 239 (Minn. 1984).