SHELLY NEMITZ, Employee/Appellant, v. WALKER METHODIST, SELF-INSURED/BERKLEY RISK ADM'RS CO., Employer, and IMI CORNELIUS INC., and OLD REPUBLIC/ALEXSIS RSKCO, Employer-Insurer, and MN DEP=T OF ECONOMIC SEC., MN DEP=T OF HUMAN SERVS., FAIRVIEW SOUTHDALE HOSP., BLUE CROSS/BLUE SHIELD and BLUE PLUS, TWIN CITIES ORTHOPEDICS, and SUBURBAN RADIOLOGIC CONSULTANTS, Intervenors.

 

WORKERS= COMPENSATION COURT OF APPEALS

APRIL 21, 2004

 

HEADNOTES

 

CAUSATION - SUBSTANTIAL EVIDENCE.  Substantial evidence, including expert medical opinion and the employee=s lack of medical treatment for many years, supports the compensation judge=s finding that the employee=s 1990 work injury was not a substantial contributing cause of her current low back condition.

 

Affirmed.

 

Determined by: Rykken, J., Stofferahn, J., and Pederson, J.

Compensation Judge: Kathleen Behounek

 

Attorneys: David B. Kempston, Law Office of Thomas D. Mottaz, Anoka, MN, for the Appellant.  Mark A. Kleinschmidt and Ted A. Johnson, Cousineau, McGuire & Anderson, Minneapolis, MN, for the Respondents.

 

OPINION

 

MIRIAM P. RYKKEN, Judge

 

The employee appeals from the compensation judge=s denial of her claims based on the findings that the employee=s April 13, 1990, low back work-related injury did not substantially contribute to her low back complaints and need for treatment after November 2000.  We affirm the compensation judge=s findings in their entirety.

 

BACKGROUND

 

Shelly Nemitz, the employee, claimed entitlement to benefits based upon an admitted work-related injury she sustained to her low back on April 13, 1990.^[1]  On that date, while employed at Walker Methodist as a nursing assistant, the employee injured her lumbar spine while transferring a patient from his bed to a wheelchair.  As the patient sat back on his bed, his feet slid out from under him, and to prevent the patient from hitting the back of the bed frame, the employee reached forward to support his head.  As she did so, she felt a popping sensation on the right side of  her low back, and immediately noted pain radiating into her right buttock and the back of her thigh.  She was unable to complete her work shift, and consulted Dr. David Parker that same day, reporting low back and right leg pain.  Dr. Parker diagnosed acute lumbar strain, secondary to the lifting incident.  He later prescribed pain medication and ice packs.  Dr. Parker restricted the employee from work for two weeks, later prescribed physical therapy and released the employee to return to work on a light duty basis.  She returned to work in May 1990, continued to work until approximately May 15, 1990, and then discontinued her work due to increased symptoms.  Although the employee later returned to work, she again remained off work between July 11, 1990, and January 3, 1991, during which time she was paid temporary total disability benefits by Walker Methodist.

 

The employee underwent chiropractic treatment from Dr. Gary Fieber, who referred her to an orthopaedic surgeon, Dr. Thomas Raih.  The employee first consulted Dr. Raih on July 17, 1990.  At his recommendation, she underwent an MRI scan of the lumbar spine on July 23, 1990, which showed degenerative disc disease at the L5-S1 level with a small to moderate central posterior herniation of the L5-S1 intervertebral disc.  Approximately two weeks later, the employee received  an epidural steroid injection in her low back, due to her increased symptoms.

 

Based on her diagnosis and the results of a functional capacity evaluation, the employee was precluded from returning to her work as a CNA.  By October 3, 1990, Dr. Raih assigned a lifting restriction of 50 pounds.  The employee participated in a work-hardening program, and received rehabilitation assistance, eventually returning to work for Walker Methodist as a home health aide.  She also received physical therapy, exercised at a health club, and utilized a TENS unit for three months.  The employee continued to note low back pain including an aggravation of her pain following a slip and fall incident on November 26, 1990.

 

In his report of April 12, 1991, Dr. Raih concluded that the employee had reached maximum medical improvement, and assigned a 9% whole body impairment rating pursuant to Minn. Rule 5223.0070, subp. 1B(1)(A), based on a herniated disc at the L5-S1 level. 

 

The employee aggravated her symptoms as the result of another slip and fall incident at home on July 31, 1991.  X-rays taken after this incident noted no significant change, and the employee testified that this incident did not permanently worsen her low back condition.  She also twisted her low back in a home incident in early January 1992.  The employee was seen by Dr. Paul Silverstein for a neurological consultation on January 13, 1992, at which time she reported continuing pain in her low back with pain radiating into her right thigh and leg.  Dr. Silverstein assessed chronic low back pain resulting from her 1990 work injury, and recommended a supervised exercise program to attempt to straighten her low back and to improve her tolerance for pain.

 

The employee testified that her symptoms continued through the late 1990's.  Although she sought no medical or chiropractic treatment for her low back symptoms between January 1992 and August 1998, she continued to experience low back pain and radicular symptoms throughout this time and treated with over-the-counter pain medication.  She underwent chiropractic treatment between August and October of 1998, complaining of low back pain, headaches and neck pain.  Thereafter the employee sought no treatment for low back complaints between October 1998 and November 2000.

 

Following her 1990 work injury, the employee returned to work for Walker Methodist as a home health aide, and continued working there until approximately 1992, when she left her employment with Walker Methodist for reasons unrelated to her work injury.  At the time the employee discontinued working for Walker Methodist, she was working on a light-duty basis.  She held several positions after leaving the employ of Walker Methodist, including shipping and assembly jobs. The employee testified that certain tasks aggravated her low back symptoms, and that she has experienced constant low back pain and intermittent leg symptoms since her 1990 injury. 

 

The employee began working on a full-time basis for IMI Cornelius in January 1997, working in several positions including machine operator, spot welder and assembly work.  The employee underwent a pre-employment physical examination prior to starting work for Cornelius, and no restrictions were placed on the employee=s work activities as a result of that examination.  The employee=s work for Cornelius evidently did not require repetitive lifting of weight greater than 20 pounds and did not require repetitive overhead work.  However, her duties included repetitive upper extremity work, bending, lifting sheet metal, pushing carts loaded with large sheets of metal, lifting and carrying metal coils, crimping sheets of metal, and shaking sheets of metal to remove metal scraps punched out during the machining process.  The employee testified that these various tasks caused neck pain, as well as pain in her shoulders and hands, and that her work at Cornelius also worsened her low back symptoms.  She performed the above tasks approximately two years while working for Cornelius, in part while constructing beverage dispensing machines.  For approximately six months at Cornelius, the employee also assembled large boxes using a power drill or screwdriver, and for approximately six months worked on hydraulically pressurized tanks, lifting and testing them; according to the employee, the tanks weighed in excess of 30 pounds.  She also performed spot welding of heavy metal pieces, which she again claims aggravated her neck symptoms.

 

During the employee=s employment with Cornelius, she missed time from work at various periods of time when laid off between August 1997 and January 1998 and again from September 1998 and January 1999.  The employee claims that she sustained a neck injury while working for Cornelius as a machine operator in 1998 and 1999, noting increased neck and low back pain as a result of running a machine and lifting pieces of steel to be fabricated into panels used for constructing beverage dispensing machines.  The employee first received chiropractic treatment for her neck in August 1998.  She also reported that she had injured her back and neck when she tripped on a pallet on the floor, and that she fell again in 1999 when her right leg gave out, causing her to strike her right knee and incurring more back and neck pain.

The employee missed a significant amount of time from work at IMI Cornelius due to various medical conditions, including hyperthyroidism (Graves= disease), tachycardia, migraine headaches, and depression.  In approximately 1999 the employee was diagnosed with Graves= disease, which required her to take a leave of absence of several months= duration.  The employee stopped working at IMI Cornelius on June 8, 2000, when she took a medical leave of absence due to her Graves= disease and heart condition.  Her employment status with Cornelius was terminated as of November 1, 2000.

 

On November 14, 2002, the employee again consulted Dr. Raih, complaining of  recurrent low back pain and left leg discomfort.  At that time, she remained off work due to her Graves= disease.  She complained particularly of low back discomfort as well as right-sided neck pain with bilateral shoulder pain and numbness and tingling in the fingertips.  Dr. Raih diagnosed degenerative lumbar disc disease, mild sclerosis and Graves= disease, and recommended anti-inflammatories and a work restriction of no lifting over 50 pounds. 

 

At Dr. Raih=s referral, the employee underwent an MRI scan of the cervical spine on December 14, 2000, which revealed a congenital bony canal stenosis from C3 to C6 with moderately severe, central canal stenosis at C4-5 and degenerative changes throughout.  An MRI scan of her lumbar spine revealed a small central to right paramedian L5-S1 disc protrusion.

 

The employee continued to receive treatment for her Graves= disease with Dr. Rachko, who referred her to an orthopaedic spine surgeon, Dr. Jos Cove, for further consultation.  Dr. Cove first examined the employee on January 8, 2001.  She reported neck and low back pain present for more than 10 years, and reported that her neck pain had significantly increased over the past year.  Dr. Cove concluded that the employee had chronic neck and low back pain that had been an ongoing process since her work injury in April 1990.  Dr. Cove, however, thought that the changes in the employee=s neck were most likely not related to a lifting injury, but that Aher low back changes certainly could be consistent with this.@  Dr. Cove referred the employee for physical therapy to address both her low back and neck complaints.  He also advised the employee that, although she was not yet a surgical candidate, perhaps surgery to her cervical spine may be appropriate in the future.  In his report dated August 29, 2001, Dr. Cove concluded that the employee=s 1990 injury led to chronic low back pain and significantly aggravated a pre-existing condition.  He also concluded that the 1990 injury significantly contributed to the employee=s  current symptoms, based in part on the lack of any significant change in her MRI scans during the period since the 1990 injury.   He further explained that

 

In summary, the lifting injury 4/13/90 led to chronic low back pain and the mechanism here is a significant aggravation of a preexisting injury.  The fluctuation in the intensity of symptoms is certainly not unusual in patients with chronic low back pain and although at several points in time a maximum medical improvement may appear to have been reached.  This is clearly a legal term and not a medical term.  It is not impossible for patients to have significantly less symptoms for quite some time and then recurrence of symptoms. The fact that her MRI scan was essentially unchanged, or at least that the changes on her latest MRI scan are a logical consequence of the earlier scan from 1990, and that there are not significant changes in adjacent discs, also strongly favors a conclusion that current symptoms are related to the initial injury of this patient. 

 

Dr. Cove referred the employee to Dr. Steven Stein, a neurologist at the Minneapolis Clinic of Neurology, to assess her intense headaches.  Dr. Stein examined the employee on September 11, 2001, at which time she  reported both neck and low back pain.  Dr. Stein recommended either another epidural steroid injection or chronic pain management to treat her low back pain.  He expressed doubt that surgery was indicated for the employee=s low back, but also  stated that the employee might require cervical spine surgery in the future, and recommended periodic neurologic review of her cervical spine.  On October 5, 2001, Ms. Nemitz underwent a cervical laminoplasty from C3 to C7, performed by Dr. Cove, to treat her underlying spinal stenosis.

 

In a report of January 7, 2002, Dr. Stein provided an opinion on the causation of the employee=s low back condition, stating as follows:

 

On the basis of all the information available to me, it would be my opinion that the work injury of April 13, 1990, constitutes a substantial contributing cause for her current lower back condition.  This appeared to be the episode where her lower back problems started.  I am not aware of any other significant injuries to her lower back.

 

Dr. Stein concluded that the medical treatment provided to the employee for her low back had all been Areasonable things to pursue relative to her lower back problems originating from her 1990 work injury.@  Dr. Stein also concluded that the employee=s cervical spine condition resulted in part from her work activities at IMI Cornelius, although her condition was also related to a congenital condition.  Dr. Stein again recommended an epidural steroid injection to treat the employee=s low back, and also suggested consideration of a chronic pain program to help the employee deal with her chronic pain. 

 

On May 24, 2001, the employee filed a claim petition against Walker Methodist, claiming entitlement to payment for various outstanding medical treatment expenses incurred since approximately November 2000, which she claimed were causally related to her 1990 work injury.  Walker Methodist, self-insured employer, admitted that the employee sustained a low back injury on April 13, 1990, but contended that the employee=s current low back complaints and resulting treatment were not causally related to that injury.  The employee later amended her claim petition to include a claim against IMI Cornelius, alleging that she had sustained a Gillette^[2] injury  to her cervical spine, culminating on or about June 8, 2000, while working at Cornelius.  The employee sought payment of temporary total disability benefits from November 1, 2000, and continuing, along with payment of various medical treatment expenses and provision of rehabilitation assistance and retraining benefits.  IMI Cornelius and its insurer, Old Republic, denied primary liability for the claimed Gillette injury to the cervical spine, and also contended that the employee=s claims were barred based on failure to provide timely notice of the claimed injury.

 

On February 20, 2002, the employee underwent additional MRI scans of her lumbar and cervical spine.  The MRI of the lumbar spine was interpreted as showing no change since the MRI performed in 1990, and the MRI of the cervical spine was interpreted as showing no additional disc protrusions or herniations, nor any additional degenerative disc disease, since the December 2000 scan.

 

On April 9, 2002, the employee underwent an independent medical examination with Dr. Jack Drogt, at the request of Walker Methodist.  Dr. Drogt confirmed that the employee sustained a low back injury in April 1990, and diagnosed degenerative disc disease of the low back with a small central to right paramedian L5-S1 disc protrusion without neural impingement.  Dr. Drogt also diagnosed  multi-level degenerative disc disease with central spinal stenosis of the cervical spine, with chronic neck pain, but concluded that the employee did not injure her neck as a result of her 1990 injury.  He stated that the employee Ahas symptoms of chronic low back and neck pain, however, her disability relates to a history of depression.@  He also concluded that the employee was not permanently totally disabled as a result of her low back condition but instead was employable.  Dr. Drogt placed restrictions on the employee due to her low back condition, including a 50-pound limit on her lifting and carrying and a limitation of bending and flexing.

 

On June 4, 2002, the employee underwent an independent medical examination with Dr. Mark Friedland, at the request of IMI Cornelius, at which time she reported continued low back pain along with constant neck pain and headaches with diffuse bilateral upper extremity intermittent pain.  Dr. Friedland concluded that neither the 1990 or 2000 claimed injury substantially  contributed to the employee=s cervical spine condition and need for medical treatment.  He also concurred with Dr. Raih=s assessment that the employee had reached maximum medical improvement from her low back injury by at least April 18, 1991, and that the employee has sustained no additional permanent partial disability relative to her low back beyond the 9% earlier rated.  Dr. Friedland also concluded that A[o]ther than an independent stretching and lumbar stabilization program as well as aerobic conditioning via walking, I do not believe that Ms. Nemitz requires any further . . . ongoing care or treatment for her low back condition.@

 

After Dr. Cove left his local orthopedic practice, the employee received follow-up treatment from Dr. Edward Southern, who, by June 2002, recommended additional cervical spine surgery.  On July 25, 2002, Dr. Southern performed a two-level cervical fusion,  which the employee advised resulted in an improvement of her symptoms.  She ultimately obtained employment, and worked for Tasty Pizza between August 26, 2002, and February 7, 2003.  The employee continued receiving medical treatment for her low back.  She underwent a lumbar discogram in October 2002 which showed concordant pain at two levels.  The employee testified that Dr. Southern scheduled her for an anterior posterior fusion surgery in February 2003; in December 2002, the employee was fit for a lumbo-sacral orthosis or brace to support her low back during her post-operative healing.  The employee testified that she left the employ of Tasty Pizza in February 2003 due to a combination of a decrease in that company=s business and her impending low back surgery.  At the time of the hearing, the employee had not yet undergone surgery to her low back, as it apparently was postponed until after Dr. Southern returns from active duty in the military reserves.

 

At Dr. Southern=s referral, Dr. Jeffrey Dick examined the employee on February 19, 2003.  The employee reported progressive low back symptoms and bilateral leg symptoms, and that her legs frequently Agave out,@ causing her to fall down.  Dr. Dick assessed the employee as a poor candidate for surgery, based on positive Waddell signs and lower extremity symptoms which he found to be unexplainable from her MRI scan.

 

Dr. Drogt re-evaluated the employee on March 13, 2003, and again diagnosed chronic mechanical low back pain as a result of mild degenerative disc disease.  He recommended against the two-level fusion surgery suggested by Dr. Southern, determining that Athere are sufficient non-organic signs that might lead me to believe that there is an element of symptom amplification that could compromise any post-operative result, however well intentioned surgical treatment is.@  Instead, Dr. Drogt recommended continued non-operative care, including a stretching and strengthening program, aerobic conditioning and regular exercise.  In follow-up reports of April 10 and 29, 2003, Dr. Drogt concurred with Dr. Dick and again concluded that the employee would be a poor candidate for surgical treatment.

 

This matter was heard before a compensation judge on June 26, 2003.  In her Findings and Order, served and filed on August 21, 2003, the compensation judge found that the employee=s April 13, 1990, low back injury did not substantially contribute to the employee=s low back complaints and need for treatment after November 2000.  The judge also found that the evidence failed to show that the employee sustained a work-related Gillette injury to her cervical spine on or about June 8, 2000, as a result of her work activities with Cornelius.  The judge found that the employee was disabled from work on June 8, 2000, as a result of her Graves= disease, and denied the employee=s claims for disability benefits and medical treatment expenses incurred from and after November 1, 2000, concluding that neither was causally related to either the employee=s April 13, 1990, low back injury sustained at Walker Methodist nor her work activities with Cornelius through June 8, 2000.  The employee appeals from the findings that the employee=s April 13, 1990, low back injury at Walker Methodist does not represent a substantial contributing factor to the employee=s disability and need for treatment from and after November 1, 2000.  The employee has not appealed from the compensation judge=s finding that the employee did not sustain a work-related Gillette injury to her cervical spine on or about June 8, 2000, as a result of her work activities with Cornelius. 

 

STANDARD OF REVIEW

 

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, 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.@  Northern States Power Co. v. Lyon Food Prods., Inc., 304 Minn. 196, 201, 229 N.W.2d 521, 524 (1975).

 

DECISION

 

The employee appeals from the compensation judge=s determination that her admitted work injury in 1990 did not substantially contribute to her disability and need for medical treatment since 2000. The employee argues that this determination does not comport with substantial evidence of record and ignores the fact that the 1990 injury is an admitted permanent injury.  The employee contends that the compensation judge erroneously concluded that the causal connection between the employee=s permanent 1990 work injury and current low back condition had been severed, and she  argues that she has sustained no superseding intervening injury to her low back since her 1990 injury.  The employee cites to the various medical causation opinions that link her 1990 injury to her current condition,  including those of Drs. Stein and Cove, and also points to her testimony that she has experienced ongoing low back pain ever since that injury, contending that there is no evidence in the record to refute that testimony. 

 

The employee relies primarily on the medical opinions of two physicians, Drs. Stein and Cove, for support of her arguments.  In his report dated August 29, 2001, Dr. Cove outlined his opinion that the employee=s work injury of April 13, 1990, significantly contributed to the employee=s current symptoms, based on her well-documented injury and a 10-year period of recurrent symptoms in spite of medical treatment. Although Dr. Cove concluded that the employee=s findings on the MRI scan of July 1990 documented changes present for quite some time, he concluded that the 1990 work injury significantly aggravated the employee=s pre-existing condition.

 

In a letter dated January 7, 2002, Dr. Stein provided his opinion that the employee=s work injury of April 13, 1990, constituted a substantial contributing cause for her current lower back condition.  He also concluded that the medical care the employee had received for her low back had been reasonable to treat her lower back problems originating from the 1990 work injury. Upon his review of updated medical records, Dr. Stein issued another report dated May 22, 2003, in which he reiterated his opinions on causation, and again recommended a chronic pain management program.

 

Questions of medical causation fall within the province of the compensation judge.  Felton v. Anton Chevrolet, 513 N.W.2d 457, 50 W.C.D. 181 (Minn. 1994).  And, although there is support in the record for the employee=s claim, the issue on appeal is not whether substantial evidence would support an alternative finding, but whether substantial evidence supports the judge=s findings.  The compensation judge found that the evidence in this case fails to show that the employee=s current low back complaints are causally related to her April 13, 1990, work injury.  Although the judge acknowledges the employee=s testimony about her ongoing low back complaints since 1990, the judge found it significant that, but for a limited period in 1998, the employee sought no medical treatment for her low back between January 1992 and November 2000.  The judge noted that the

 

employee received treatment and sought social security benefits for numerous health problems between 1998 and November 2000, but failed to note any significant low back complaints or problems performing her work activities due to low back complaints.  The evidence showed that the employee in fact performed all of her work duties without requesting modifications as a result of low back difficulties.  The employee did miss significant periods of time from work, but for reasons unrelated to her low back.  In particular, the employee missed significant periods of work while employed by Cornelius.  The medical records indicated that other health concerns were the cause of the absences.  The employee testified that some of the jobs she performed after her employment with Walker involved physical activity, including lifting.  Again, the evidence does not show that the employee had difficulties perform[ing] the physical aspects of her work after her employment with Walker.

 

(Memo. p. 5.)

 

The compensation judge had the opportunity to review the voluminous medical records in evidence, as well as the employee=s testimony and that of a representative from IMI Cornelius.  She found the opinions of Dr. Drogt to be consistent with the facts and evidence in the record.  Dr. Drogt, who examined the employee on April 9, 2002, and March 13, 2003, diagnosed chronic mechanical low back pain as the result of mild degenerative disc disease, and stated in his March 13, 2003, report that

 

I believe Ms. Nemitz=s current diagnosis would be construed as age-specific, and is unrelated to the 1990 injury at Walker Methodist.  Certainly, the degree of degenerative change noted on MR [sic] is compatible with that of a 40-year-old individual.  Furthermore, the nature of her symptoms is not substantiated by objective findings.

 

The judge adopted Dr. Drogt=s opinion that the employee=s 1990 work injury no longer represents a substantial contributing cause of her low back condition or symptoms.  The employee argues that the compensation judge=s reliance on Dr. Drogt=s causation opinion was misplaced, since Dr. Drogt reversed his opinion between his 2002 and 2003 reports.  The employee argues that Dr. Drogt=s first opinion leads to the conclusion that the 1990 work injury was permanent, and therefore his later and inconsistent causation opinion is erroneous.  However, Dr. Drogt=s opinions are not entirely inconsistent with each other, on the issue of the causation of the employee=s current low back condition.  As the employer argues, after his initial examination of the employee, Dr. Drogt reviewed additional medical records, reexamined the employee, and issued his supplemental opinion.  This additional information, the employer argues, may have caused Dr. Drogt to revise his opinion on causation.  In addition, a compensation judge generally Amay accept all or only part of any witness= testimony.@  City of Minnetonka v. Carlson, 298 N.W. 2d 763, 767 (Minn. 1980).  Furthermore, it is the compensation judge's responsibility, as trier of fact, to resolve conflicts in expert testimony, and a judge=s choice between expert opinions is generally upheld unless the facts assumed by the expert in rendering his opinion are not supported by the evidence.  Nord v. City of Cook, 360 N.W.2d 337, 342, 37 W.C.D. 364, 372 (Minn. 1985)

 

                          In this case, the compensation judge chose the causation opinions of Dr. Drogt over those of Drs. Stein and Cove, and determined that the employee=s 1990 low back injury no longer substantially contributes to the employee=s current condition and low back symptoms.  As Dr. Drogt=s opinion was based on adequate foundation, the compensation judge=s choice of a doctor=s opinions will not be overruled.  Nord v. City of Cook, 360 N.W.2d 337, 37 W.C.D. 364 (Minn. 1985).

 

The employee also argues that Dr. Drogt=s reports support the employee=s claim that her low back treatment since 2000 has been reasonable and necessary.  Even if that were the case, Walker Methodist disputes the causal relationship between the employee=s 1990 injury and her later need for medical treatment.  The compensation judge relied on the causation opinions expressed by Dr. Drogt in reaching her conclusion that no such causal relationship exists.  As the compensation judge=s determination is supported by substantial evidence and is not clearly erroneous, we must, under this court=s standard of review, affirm that decision.  Hengemuhle v. Long Prairie Jaycees, 358 N.W.2d 54, 37 W.C.D. 235 (Minn. 1984).