The employer and insurer appeal from the compensation judge’s findings that the employee’s March 5, 2007, personal injury was a permanent aggravation of the employee’s pre-existing spinal condition and that the proposed lumbar spine fusion surgery was reasonable, necessary, and causally related to the employee’s work-related injury.  We affirm.

Lemuel Johnson, Sr., the employee, sustained an admitted personal injury to his low back on March 5, 2007, while working as a circuit assembler for Micro Control Company, the employer.  The employer was then insured for workers’ compensation purposes by Chubb Group of Insurance Companies.

There is no dispute the employee had low back problems prior to March 2007.  The employee reported occasional low back and leg symptoms since about 1988.  In the fall of 1995, he received treatment at Richland Medical Center for low back pain radiating into the left thigh.  He was treated conservatively and gradually improved.

In October 1996, the employee sustained a low back injury while employed by Cardinal Glass in Spring Green, Wisconsin.  He received conservative treatment for back and leg pain at Richland Medical Center and the rehabilitation medicine department at the University of Wisconsin Hospital and Clinics, but did not improve.  An MRI scan on December 10, 1996, showed a moderate disc herniation at L4-5 and a small to moderate left lateral disc herniation at L5-S1 compressing the left nerve root.  Dr. Clifford Tribus, an orthopedic surgeon at the University of Wisconsin, performed a discectomy and hemilaminectomy at L4-5 and L5-S1 on March 19, 1997.

In May 1997, at his six week checkup, the employee reported significant relief of his lower extremity pain, with some persistent low back pain.  He was released to return to work with a 20 pound lifting restriction, with no standing for more than 4 hours, and frequent position changes throughout the day.  The employee returned to light-duty work at Cardinal Glass.  At the employee’s one-year post surgery follow-up in March 1998, Dr. Tribus noted the employee continued to have low back pain and occasional lower extremity pain, but stated there was no evidence of increased deformity of the lumbar spine secondary to the surgery and no evidence of advanced degenerative disc disease.  The employee last saw Dr. Tribus on August 10, 1998.  The doctor stated the employee did not need to limit himself in any way other than the 20 pound lifting restriction.  Physicians at Richland Medical Center continued to prescribe Percocet, for low back pain, through November 1998.

The employee was next seen at the Regina Medical Group (Regina Clinic) in Hastings, Minnesota, on January 16, 1999, for complaints of nasal congestion.  Dr. Lon Peterson took a history of some chronic low back pain for which the employee received Percocet, and a two-level surgery for disc disease in 1997.  No treatment was provided for the back.

The employee was seen by Dr. Garrick Olsen at the Regina Clinic on February 23, 2001, for multiple complaints, including light-headedness, tingling in the thumb and index finger, sinusitis, and migraines.  A history of low back pain and lumbar disc disease was noted, and the employee reported worsening lower extremity pain.  The doctor prescribed a TENS unit and ordered an MRI scan.  The scan, performed on March 1, 2001, showed normal findings at L3-4, a laminotomy at L4-5 with granulation tissue, and a laminotomy at L5-S1 with granulation tissue and a posterior disc bulge with mild left forminal stenosis.  There was no evidence of a recurrent disc herniation.  At a March 2, 2001, follow-up visit, the doctor stated the employee’s lumbar spine was essentially normal and the employee was doing well.

The employee was next seen for low back complaints in January 2004, by Dr. James Noreen at the Regina Clinic.  The doctor noted a history of lumbar disc disease with a laminectomy and discectomy at L4-5 and L5-S1 in 1997, diagnosed lumbar disc disease, and prescribed a prednisone burst, ibuprofen, Tylenol #3, and physical therapy.  The employee improved with physical therapy and by March 4, 2004, requested a hold on further therapy, reporting his low back pain was no longer constant and he had no tingling or numbness into his legs.  The employee was seen once more on October 4, 2004, when he was diagnosed with a low back strain, and was given Tylenol #3.

On March 5, 2007, the employee was injured in a slip and fall on ice in the employer’s parking lot and was seen at the Unity Hospital emergency room reporting a stiff neck and lower back.  He was prescribed Vicodin and Flexeril and taken off work for two days.  The employee was seen by Dr. Peterson at the Regina Clinic the following day.  The doctor noted a past history of chronic low back pain with a previous surgery at L4-5 and L5-S1.  The employee was released to return to work the next day, and advised to follow-up with Dr. Noreen, his family physician.

The employee saw Dr. Noreen on March 13, 2007.  He had returned to work, but reported that lifting seemed to be irritating his back.  The doctor prescribed a Medrol Dosepak and Percocet for pain, and limited the employee to occasional lifting up to 20 pounds, no bending, and limited twisting and turning,  The employee continued to complain of low back pain and pain down his leg, and Dr. Noreen ordered an MRI scan and physical therapy.  The scan, performed on April 13, 2007, showed stable post-surgery granulation at L4-5 and stable, but severe, L5-S1 neural foraminal stenosis with impingement on the left L5 nerve root.  There was no evidence for a recurrent or residual disc herniation or a new lesion.

On April 18, 2007, Dr. Noreen observed the employee was not working, and continued to have pain in the back radiating to the leg.  The doctor diagnosed lumbar disc disease with radiculopathy, work-related, and referred the employee for a neurological evaluation.  The employee continued to participate in physical therapy through July 2007, showing some improvement, but reporting low back pain, radiating pain into the lower extremities with some leg weakness, and fatigue with exercise.

The employee was seen by Dr. Neil Dahlquist at Capitol Neurology on July 10, 2007.  Dr. Dahlquist took a history of a previous successful lower back surgery, and the fall on ice at work on March 5, 2007.  Dr. Dahlquist reviewed the MRI scan and diagnosed lumbar spondylosis, noting the employee had significant stenosis at L5-S1 that was probably responsible for the employee’s leg complaints.  The doctor prescribed Neurontin, ordered an EMG, and referred the employee to Minnesota Spine Rehabilitation.  The lower extremity EMG on August 10, 2007, showed mild, chronic neurogenic changes involving the left L5-S1 innervated muscles, but no acute denervation.  The employee was evaluated at Spine Rehabilitation on September 11, 2007, where he was found not to be a suitable candidate for the program.

On September 19, 2007, the employee was seen by Dr. David Florence, an orthopedic surgeon, at the request of the employer and insurer.  Dr. Florence took a history, reviewed medical records, and examined the employee.  The doctor concluded the employee had perceived back pain with no objective radiculopathy confirmed by EMG, with functional overlay.  Dr. Florence opined the incident on March 5, 2007, did not cause the employee’s current conditions, nor did it aggravate, accelerate, or exacerbate any pre-existing condition beyond its normal progression.

The employee returned to Dr. Tribus for a second opinion on September 24, 2007.  The doctor noted the employee had done well in the intervening years until the March 5, 2007, slip and fall at work.  Dr. Tribus concluded the April 2007 MRI scan showed very mild stenosis of the left L5 nerve root, opined that surgical intervention was not indicated at that time, and recommended continued physical rehabilitation.

In October 2007, Dr. Noreen noted that the employee continued to have back symptoms and fatigued easily with repetitive activities.  He continued the employee’s work restrictions and referred the employee to Physicians’ Neck and Back Clinic (PNBC) for more intensive rehabilitation.  The employer was unable to accommodate the employee’s restrictions and he remained off work.

The employee was seen at PNBC on May 5, 2008.^[1]  Dr. Caroline Mason took a history of the employee’s lumbar laminectomy by Dr. Tribus with good results.  The employee reported both right and left leg pain currently, stating both his back pain and leg pain were worsening.  The doctor assessed mechanical low back pain and deconditioning, and recommended participation in an active rehabilitation program.  The employee completed 14 sessions with only slight progress, and therapy was discontinued on July 24, 2008.

The employee returned to Dr. Dahlquist on August 20, 2008, reporting worsening symptoms.  The doctor assessed chronic lumbar spondylosis and pain syndrome.  He agreed the employee was not a surgical candidate, and again referred the employee to Minnesota Spine Rehabilitation.  The employee returned to see Dr. Noreen on August 27, 2008, who referred the employee to Dr. Leland Scott at the Minneapolis Clinic of Neurology for further evaluation.

Dr. Scott examined the employee on October 28, 2008.  The doctor noted a history of a prior low back surgery in 1997 in the nature of a L4-5, L5-S1 laminotomy and the 2007 fall.  Dr. Scott reviewed the April 2007 MRI scan, interpreting it to show severe left L5-S1 narrowing, impinging the left L5 nerve root.  On examination, the doctor noted radicular sensory loss over the L4 dermatomes bilaterally, mildly reduced over the L5 dermatomes, and left more than right S1 dermatomes.  Dr. Scott concluded the employee had findings consistent with chronic musculoskeletal pain in the low back with evidence of symptomatic lumbar radiculopathy from L4 to S1.  The doctor prescribed Percocet, ordered a repeat MRI scan, and referred the employee for an epidural injection.  The January 15, 2009, MRI scan was read as showing disc degeneration L3 to S1; right foraminal and bilateral disc herniation impinging on the right L3 nerve root and mild facet arthropathy at L3-4; status post laminectomy, moderate facet arthropathy, mild foraminal narrowing bilaterally at L4-5; and status post laminectomy, mild facet arthropathy, moderate left foraminal stenosis without nerve root impingement, and mild right foraminal narrowing at L5-S1.

A bilateral L5 transforaminal epidurography and therapeutic injection was performed on January 29, 2009, with minimal improvement in back or lower extremity pain.  In follow-up on March 3, 2009, Dr. Scott concluded the employee’s lack of response to the epidural injection suggested lumbar facet arthropathy as the primary source of the employee’s pain, with secondary muscle spasm.  The doctor prescribed a prednisone taper and diagnostic medial branch blocks.  The injections, completed on March 16, 2009, were indeterminate and resulted in no significant change in symptoms.  In follow-up on April 24, 2009, Dr. Scott observed that the employee’s history and findings were consistent with chronic musculoskeletal pain in the low back with symptomatic radiculopathy involving L4-5 and L5-S1.  He referred the employee for a CT mylogram, and prescribed a two-day course of Valium to see if the low back pain was due to muscle spasm.  Dr. Scott remained puzzled as to why the employee’s radicular pain did not respond to the prednisone or nerve root injections.

The CT mylography, performed on May 14, 2009, revealed an annular bulge to the right with mild to moderate subarticular recess stenosis and mild foraminal narrowing on the left at L3-4.  At L4-5 there was an annular bulge and a broad-based far lateral right-sided disc protrusion with mild bilateral facet arthropathy.  The L5-S1 level showed mild facet arthropathy and ligamentous thickening on the left contributing to subarticular recess stenosis with impingement of the left S1 nerve root, and osteophyte formation with moderate foraminal stenosis on the left and mild ganglionic impingement.  On follow-up Dr. Scott assessed low back pain primarily due to multilevel facet arthritis, and prescribed another two day Valium trial and repeat medial branch blocks.  The blocks again produced no change in symptoms, and Dr. Scott ordered a three-level lumbar discography to identify any discogenic source of the employee’s back pain.  The discography, completed on September 22, 2009, showed severe concordant low back and right leg pain at L4-5 and L5-S1 and nonconcordant pain at L3-4 with abnormal disc morphology with a right-sided annular tear.  In a letter report dated October 23, 2009, Dr. Scott stated the diagnostic tests showed evidence of multilevel degenerative changes with foraminal stenosis at multiple levels, with subarticular recess stenosis most notable at L5-S1, clearly impinging the S1 nerve root.  Dr. Scott concluded the employee’s back pain had multiple causes, including lumbar disc pain, which appeared to be the major treatable source of his pain through a fusion.  The doctor further noted that the employee’s radicular pain remained resistant to treatment for reasons he could not ascertain.  Dr. Scott stated that the employee was having significant problems with ambulation and activities of daily living as a result of his pain, that a fusion appeared to be the only means by which he might obtain relief from his pain, and referred the employee to Dr. Manuel Pinto for a surgical evaluation.

The employee was examined by Dr. Pinto at the Twin Cities Spine Center on December 3, 2009.  Dr. Pinto noted a two-year history of worsening low back pain and leg pain along with prior back surgery, a laminectomy at L5-S1.  The doctor conducted an examination of the employee and reviewed the most recent MRI scan and the employee’s discograms.  Dr. Pinto’s impression was multilevel disc degeneration at L3-4, L4-5, and L5-S1, right-sided foraminal stenosis at L3-4, and left-sided foraminal stenosis at L4-5 and L5-S1, with discogenic pain.  The doctor noted the employee had gone through every conceivable conservative management and nothing seemed improved.  Dr. Pinto ordered control discograms at L1-2 and L2-3 in anticipation of surgery.  The discograms revealed no significant problems at the levels above L3, and Dr. Pinto recommended a three-level anterior-posterior fusion from L3 to S1 with laminotomies to decompress the foramen at those levels.

In a letter report dated January 6, 2010, Dr. Scott stated the employee’s low back pain was clearly multifactorial, but that much of it stemmed from the March 2007 fall.  The doctor concluded that while the employee had evidence of static mild lumbar radiculopathy, his symptoms primarily appeared to be the result of a combination of discogenic pain with secondary muscle spasm.

Dr. Jeffrey Dick examined the employee in January 2010 at the request of the employer and insurer.  Dr. Dick prepared a medical report and his deposition was taken in May 2010 (Resp. Ex. 17), at which time the doctor was provided with some additional medical records.  The doctor diagnosed the employee with multilevel thoracic and lumbar degenerative disc disease, chronic pain syndrome, history of depression and anxiety disorder, and status post-discectomy surgery at L4-5 and L5-S1 on the left side.  Dr. Dick opined these conditions were caused by a combination of the normal aging process together with the employee’s lifetime use of nicotine.  The doctor stated the employee did sustain a work-related injury on March 5, 2007, but opined that injury was not a substantial contributing factor to the diagnosed conditions.  Dr. Dick stated he reached this conclusion because there were no objective findings on his physical examination and because the scans, x-rays, and medical records documented almost identical symptoms prior to the March 2007 injury.  The doctor opined the employee needed no additional restrictions as a result of the work injury.  The doctor testified he would not recommend a fusion surgery because it was unlikely to resolve the employee’s symptoms and may cause additional problems in the future.  Finally, the doctor opined the employee was capable of working eight hours a day within the pre-existing restrictions.

By report dated May 10, 2010, Dr. Scott opined that the employee’s fall in March 2007 caused an exacerbation of the employee’s pre-existing back and neck symptoms and was a substantial contributing factor to the pathology causing the employee’s symptoms and physical findings.  The doctor also opined that the employee needed a lumbar fusion surgery to improve his symptoms.

By report dated July 29, 2010, Dr. Pinto noted the employee had an extensive history of back pain dating back to 1997.  Since his 1997 discectomy, the doctor stated the employee had on and off pain over the years but conservative care was sufficient to alleviate his symptoms.  Dr. Pinto stated the March 5, 2007, fall caused his symptoms to be more severe and persistent and opined that injury caused a permanent aggravation of the employee’s pre-existing condition.  Dr. Pinto recommended a three-level fusion, which he stated was likely to improve employee’s condition by 70 to 75 percent.

The employee filed a Medical Request seeking approval for the fusion surgery recommended by Dr. Pinto.  The employer and insurer filed a Medical Response denying that the proposed surgery was reasonable, necessary, or causally related to the March 5, 2007, personal injury.  Following a hearing, the compensation judge found the March 2007 personal injury was a permanent aggravation of the employee’s pre-existing spinal condition and found that the three-level anterior/posterior fusion surgery proposed by Dr. Pinto is reasonable and necessary to treat the employee’s personal injury.  The employer and insurer appeal.

The compensation judge relied upon the opinions of Dr. Scott and Dr. Pinto in determining that the March 2007 personal injury permanently aggravated the employee’s pre-existing condition and that the recommended lumbar fusion surgery was reasonable and necessary medical treatment.  The appellants contend the medical opinions of Dr. Scott and Dr. Pinto lack foundation.  There is no evidence, the appellants argue, that Dr. Scott was aware of the employee’s prior medical condition or reviewed his medical records before March 2007.  Dr. Pinto examined the employee on only one occasion and while he indicated that he reviewed prior medical records, the appellants assert the doctor failed to identify those records or discuss their contents.  In contrast, the appellants argue, Dr. Dick reviewed in detail the employee’s prior medical records, examined the employee and provided a comprehensive medical report.  The appellants claim, therefore, that only Dr. Dick offered a properly founded opinion and that the compensation judge erred in rejecting his opinion and adopting those of Drs. Scott and Pinto.  We disagree.

The employee’s counsel provided to Dr. Scott a copy of Dr. Dick’s independent medical evaluation in February 2010, and to Dr. Pinto in April 2010.  This report contained an extensive summary of all of the employee’s medical care and treatment before and after the March 2007 injury.  It is reasonable to assume this left Dr. Scott and Dr. Pinto with essentially the same foundation for their opinions as Dr. Dick had for his.  In his July 29, 2010, report, Dr. Pinto stated he reviewed a summary of the employee’s back condition and noted the employee had a “fairly extensive history of back pain going all the way back to 1997.”  (Pet. Ex. K.)  We cannot, therefore, agree with the appellants’ contention that neither Dr. Scott nor Dr. Pinto was fully aware of the employee’s pre-existing low back condition.  By the date of their medical reports, Drs. Scott and Pinto were sufficiently familiar with the employee’s past medical history, either directly or indirectly, to render causation opinions.  See Hillsdale v. Honeywell, Inc., slip op. (W.C.C.A. Feb. 6, 1997).

The competency of a witness to provide expert medical testimony depends upon the witness’ scientific knowledge and practical experience with the issue which is the subject of the offered testimony.  Reinhardt v. Colton, 337 N.W.2d 88, 93 (Minn. 1983).  In this case, both Dr. Scott and Dr. Pinto were aware of the employee’s pre-existing medical history, obtained a history of the symptoms and complaints from the employee, and performed a medical examination.  We have stated on many occasions that this level of knowledge about the subject matter affords adequate foundation for a doctor to render an expert medical opinion.  See Drews v. Kohl’s, 55 W.C.D. 33, 38-39 (W.C.C.A. 1996).

Dr. Dick opined the employee’s personal injury was not a substantial contributing factor in his current condition.  The compensation judge rejected this opinion because she concluded the doctor did not satisfactorily take into consideration the employee’s symptoms, complaints, and lack of improvement from conservative care.  The appellants assert Dr. Dick’s report contains detailed information regarding the employee’s symptoms and complaints and a detailed discussion of the conservative care undertaken to date.  They argue, therefore, the compensation judge’s reason for rejecting the opinion of Dr. Dick is inaccurate.  Whatever the merit of the appellants’ argument, ultimately the issue involves a choice between conflicting testimony of medical experts.  “Where qualified medical witnesses differ as they do here, it ordinarily is not for us on appeal to say that one is so eminently right and the other so clearly wrong that the fact finder was obliged to accept the opinion of one and discard the opinion of the other.”  Golob v. Buckingham Hotel, 244 Minn. 301, 304-05, 69 N.W.2d 636, 639, 18 W.C.D. 275, 278 (1955).  It is the compensation judge’s responsibility, as the trier of fact, to resolve conflicts in expert testimony.  Nord v. City of Cook, 360 N.W.2d 337, 37 W.C.D. 364 (Minn. 1985).  Dr. Scott, Dr. Pinto, and Dr. Dick all provided adequately founded medical opinions.  The compensation judge had to resolve a conflict in expert testimony.  The compensation judge’s adoption of the opinions of Drs. Scott and Pinto is affirmed.

The compensation judge found the March 5, 2007, injury was a permanent aggravation of the employee’s pre-existing spinal condition.  The appellants assert this finding is unsupported by substantial evidence.  They contend the compensation judge failed to fully consider the employee’s significant pre-existing low back condition and did not fully review the extensive medical records of the employee’s low back treatment prior to his personal injury.  Accordingly, the appellants assert the judge’s decision should be reversed or remanded for reconsideration.  We are not persuaded.

The appellants in their brief provide a summary of the employee’s medical treatment from 1977 through 2004.  While we will not restate that summary here, we acknowledge the employee had extensive medical treatment for his pre-existing low back condition.  In his opening statement, counsel for the employer and insurer indicated that their position was that the March 2007 injury was a temporary aggravation of the employee’s pre-existing degenerative low back condition.  Counsel then summarized much of the treatment the employee received before 2007.  The records of the employee’s extensive medical treatment were admitted into evidence.  At the hearing, the employee was cross-examined extensively regarding his prior treatment.  The employee’s medical history was summarized by Dr. Dick in his medical report and referred to in the doctor’s deposition.  Clearly, the record is replete with evidence of the employee’s treatment prior to March 2007.  The fact that the compensation judge did not specifically recite or refer to all of this medical evidence in her findings, does not, however, establish that she overlooked or failed to consider that evidence.  A compensation judge is not required to relate or discuss every piece of evidence received at the hearing.  See, e.g., Regan v. VOA. Nat’l Housing, 61 W.C.D. 142 (W.C.C.A. 2000); Pelto v. USX Corp., slip op. (W.C.C.A. Dec. 16, 1993).  Given the record in this case, we can only conclude the compensation judge did review and consider the employee’s medical records of treatment before March 2007.

The appellants next contend that a comparison of the employee’s pre- and post-injury diagnostic studies establish there was no change in the employee’s low back condition as a result of his 2007 injury.  Specifically, the appellants reference the August 1995 CT scan which, they assert, shows degenerative changes at the same levels as those at issue after the personal injury.  Similarly, they argue, the MRI scans in 1996 and 2001, when compared with the 2007 MRI, the 2009 MRI, and the 2009 lumbar myelogram and CT scan, document no change in the employee’s low back condition.  They again argue the compensation judge failed to discuss this objective and comparative evidence and clearly disregarded the employee’s significant pre-existing history documented in the medical records.  This failure, the appellants assert, mandates a reversal of the compensation judge’s decision.  We disagree.

The lumbar MRI scan in March 2001 shows no abnormalities at L3-4 or stenosis at L4-5.  The lumbar myelogram performed in May 2009 showed degenerative changes with retrolisthesis at L3-4 and subarticular recess stenosis at L4-5 and L5-S1.  These are new findings since the 2007 injury.  We cannot, therefore, agree with the appellants’ contention that the diagnostic studies establish there has been no change in the employee’s low back condition.  Further, the issue is not whether the 2007 injury produced some structural change which can be seen on an MRI scan.  Rather, the issue is whether the 2007 injury was a substantial, contributing cause of the employee’s current symptoms and need for treatment.  This is a medical-legal issue which cannot be resolved solely by a review of the radiographic studies.

The employer and insurer next argue the compensation judge’s analysis of whether the 2007 injury was a temporary or permanent aggravation was incomplete.  In determining whether an aggravation of a pre-existing condition is temporary or permanent, this court has enumerated several factors which the judge may consider including: (1) the nature and severity of the pre-existing condition and the extent of restrictions and disabilities resulting therefrom; (2) the nature of the symptoms and extent of medical treatment prior to the aggravating incident; (3) the nature and severity of the aggravating incident and the extent of restrictions and disability resulting therefrom; (4) the nature of the symptoms and extent of medical treatment following the aggravating incident; (5) the nature and extent of the employee’s work duties and non-work activities during the relevant period; and (6) medical opinions on the issue.  Wold v. Ollinger Trucking, Inc., slip op. (W.C.C.A. Aug. 29, 1994).  The appellants contend the compensation judge considered none of these factors other than the opinions of the medical experts.  Accordingly, the appellants contend the compensation judge’s analysis was incomplete and should be reversed.  We disagree.

The employee testified that his job required bending, stooping, and lifting, but that he was able to perform the job without any low back problems and missed no time from work due to his low back condition.  Following his personal injury, the employee testified his low back symptoms markedly worsened and he can no longer work.  The compensation judge noted the employee had pre-existing back problems but was able to perform his employment duties with Micro Control Company before his personal injury.  This conclusion is supported by the employee’s testimony.  Based upon the medical records in evidence, the employee had no treatment for his low back after April 25, 2001, until he sought medical treatment in January 2004 after falling on ice.  The employee attended three sessions of physical therapy in 2004, returned to see a doctor in October 2004, and then had no treatment for his low back until the March 2007 personal injury, also sustained while falling on ice.  The medical records document the nature of the symptoms and the extent of the medical treatment following the personal injury and the employee testified to his ability to work and perform non-work activities before and after the personal injury.

The significance of the Wold factors and the weight to be given the factors is a question of fact for the compensation judge.  While the compensation judge may not have specifically identified each of the factors, evidence as to each of the factors is contained in the record.  We conclude that the compensation judge properly analyzed and resolved the issue.

The issue on appeal is whether the findings of fact and orders are “clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.”  Minn. Stat. § 176.421, subd. d.1(3).  Substantial evidence, including properly founded medical opinions, support the compensation judge’s finding that the employee’s March 5, 2007, injury was a permanent aggravation of the employee’s pre-existing spinal condition.  Accordingly, we affirm.  See Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 59, 37 W.C.D. 235, 239 (Minn. 1984) (substantial evidence is evidence that “a reasonable mind might accept as adequate.”).

The compensation judge found the anterior-posterior fusion surgery recommended by Dr. Pinto was reasonable and necessary to treat the employee’s work-related injury.  The appellants contend the compensation judge failed to carefully scrutinize the medical records and failed to adequately assess the credibility of Dr. Pinto and Dr. Scott’s medical opinions in determining whether the proposed fusion surgery is reasonable and necessary.  We have considered and rejected this argument above.

The appellants further argue the compensation judge failed to take into account the significant predicting factors for success of a fusion surgery as discussed in Dr. Dick’s report and testimony.  Specifically, the appellants allege there are a multitude of factors bearing on the appropriateness of the proposed surgery including the employee’s smoking history together with his obesity, diabetic condition, chronic pain syndrome, narcotic usage, anxiety and depression.  Considering these factors, the appellants contend the proposed surgery is not reasonable or necessary.

In support of their position, the appellants cite Torgerson v. ELO Eng’g, slip op. (W.C.C.A. Mar. 16, 1994).  In that case, this court affirmed a compensation judge’s conclusion that a proposed fusion surgery was not reasonable and necessary where the judge found the treating surgeon had performed the surgery without an adequate consideration of the employee’s past treatment history, diagnostic test results, consideration of treatment alternatives, or an evaluation of the employee’s emotional and psychological fitness for surgery.  Torgerson was, however, an affirmance of a compensation judge’s finding based on substantial evidence and cases decided on this basis have little value as precedent.  See McDonel v. Andersen Windows, slip op. (W.C.C.A. Mar. 21, 2003).

In this case, there was conflicting evidence presented regarding the proposed surgery.  Dr. Dick opined the recommended surgery was not reasonable or necessary because a fusion to treat axial low back pain has been shown to have poor results when the fusion is done to treat a work-related injury and when the patient is a cigarette smoker, is dependent on narcotics, and has a history of depression.  The doctor stated that in a patient who had all of these poor predicative factors, the surgery was very unlikely to be of any benefit.  Dr. Scott opined the employee’s lumbar disc pain was amenable to treatment with a fusion surgery, which he concluded appeared to be the only means by which the employee could improve his pain.  Accordingly, Dr. Scott referred the employee to Dr. Pinto.  In his initial evaluation, Dr. Pinto noted the employee had diabetes, smoked one to two packs of cigarettes a day, and was depressed.  Clearly, Dr. Pinto took these factors into account in opining the employee’s surgery was reasonable and necessary medical care.  The doctor stated the employee had only two options, to continue conservative care that had not provided any significant relief or a lumbar fusion.  Again, the compensation judge was faced with two conflicting opinions on the issue.  The judge adopted the opinion of Dr. Pinto that the lumbar fusion was reasonable and necessary treatment to cure the employee from the effects of his personal injury.  We find no legal or factual basis to reject Dr. Pinto’s opinions.  The decision of the compensation judge is affirmed.