                IN THE SUPREME COURT, STATE OF WYOMING

                                      2014 WY 33

                                                       OCTOBER TERM, A.D. 2013

                                                                 March 5, 2014

IN THE MATTER OF THE WORKER’S
COMPENSATION CLAIM OF:

BENNIE JOHNSON,

Appellant
(Petitioner),
                                                     S-13-0115
v.

STATE OF WYOMING, ex rel.,
WYOMING WORKERS’ SAFETY AND
COMPENSATION DIVISION,

Appellee
(Respondent).

                 Appeal from the District Court of Sweetwater County
                          The Honorable Nena James, Judge

Representing Appellant:
      Donna D. Domonkos, Cheyenne, Wyoming.

Representing Appellee:
      Peter K. Michael, Wyoming Attorney General; John D. Rossetti, Deputy Attorney
      General; Michael J. Finn, Senior Assistant Attorney General; Peter Howard, Legal
      Intern.

Before KITE, C.J., and HILL, VOIGT*, BURKE, and DAVIS, JJ.

* Justice Voigt retired effective January 3, 2014.
NOTICE: This opinion is subject to formal revision before publication in Pacific Reporter Third.
Readers are requested to notify the Clerk of the Supreme Court, Supreme Court Building,
Cheyenne, Wyoming 82002, of typographical or other formal errors so correction may be made
before final publication in the permanent volume.
KITE, Chief Justice.

[¶1] The State of Wyoming ex rel. Wyoming Workers’ Safety and Compensation
Division (the Division) denied Bennie Johnson’s requests for preauthorization of bilateral
total knee replacements and payment of other medical bills associated with his knees on
the grounds the current condition of his knees was not related to a 1992 work injury. The
Medical Commission held a contested case hearing and upheld the Division’s decision.
During the hearing it admitted into evidence, over Mr. Johnson’s objection, three
exhibits. We conclude the Medical Commission did not commit prejudicial error by
admitting the exhibits and substantial evidence supports its decision. We, therefore,
affirm.

                                         ISSUES

[¶2]   Mr. Johnson presents the following issues for this Court’s consideration:

             ISSUE I

             Whether the Commission acted arbitrarily, capriciously or
             otherwise not in accordance with the law when it admitted
             into evidence unreliable and irrelevant evidence over
             objection.

             ISSUE II

             Whether the [Medical Commission’s] decision is supported
             by substantial evidence.

The Division presents the same issues, although they are phrased differently.

                                         FACTS

[¶3] Mr. Johnson has a long and complicated history of knee problems. On October 9,
1986, Mr. Johnson filed an injury report stating that a day earlier he fell ten feet while
working as a pipe welder and injured his left shoulder. It did not indicate that he injured
his knees, and he did not receive any worker’s compensation benefits for his knees.

[¶4] Several years later, while still working as a welder, Mr. Johnson was seen by
orthopedic surgeon Christian Guier, M.D. with complaints of bilateral knee pain. On the
intake questionnaire dated September 23, 1992, he stated that he had “bad knees” after
falling thirty feet in 1985(sic). Dr. Guier diagnosed him as suffering from bilateral
patellar tendonitis and chondromalacia and stated he could not rule out mild


                                            1
medial/lateral meniscopathy in both knees.1 Mr. Johnson sought worker’s compensation
benefits, and the Division concluded the time of the injury was “September 23, 1992” and
“the injury appear[ed] to be work related.”

[¶5] Dr. Guier performed surgery on both knees in December 1992, including bilateral
“arthroscopy and chondral debridement for chondromalacia patellae” and “partial
synovectomy.” 2 Although Mr. Johnson returned to work shortly after the surgeries,
within a few months he was again suffering from pain in both knees. Dr. Guier
performed a second bilateral knee operation in May 1993. Approximately one week after
the surgeries, Dr. Guier stated that he felt Mr. Johnson would “be permanently disabled
from this injury and should seek another line of employment. A referral to Vocational
Rehabilitation would be appropriate at this time.” Mr. Johnson apparently remained off
work for the next several months, and Dr. Guier continued to suggest he find a new
means of earning a living. Mr. Johnson’s knees, particularly the left, continued to bother
him, and on December 9, 1993, Dr. Guier performed a third arthroscopy and chondral
debridement of Mr. Johnson’s left knee.

[¶6] On December 23, 1993 (approximately two weeks after the left knee surgery), Mr.
Johnson’s right leg and knee were seriously injured when he was struck by a vehicle
while walking. He was diagnosed with “comminuted right knee lateral tibial plateau
fracture with disruption of the anterior cruciate ligament insertion of the lateral
meniscus,” and Dr. Guier performed surgery the next day.

[¶7] Mr. Johnson received temporary total disability (TTD) benefits until the end of
April 1995, when he accepted permanent partial disability benefits for both knees. He
also received a vocational (loss of earning capacity) award to assist him in retraining for
another occupation. He apparently used the award to start a fly fishing business
sometime in 1995.

[¶8] Even though he changed professions, Mr. Johnson continued to suffer from knee
problems. He reinjured his right knee while fishing on December 27, 1995, and
underwent additional surgeries on his right leg/knee in 1995 and 1996. The Division
denied his request for worker’s compensation benefits for the 1996 surgery, and a
Medical Commission panel upheld the denial, finding the surgery resulted from the
pedestrian/car accident rather than his work injury.



1
  Dr. Guier described chondromalacia as an abnormality or pathology of the cartilage. Tendonitis is
inflammation of a tendon, and the meniscus is a disk of cartilage in a joint. American Heritage Stedman’s
Medical Dictionary (2002).
2
  Debridement is the surgical removal of foreign matter and contaminated tissue from a wound, and
synovectomy is the removal of all or part of the synovial membrane of a joint. American Heritage
Stedman’s Medical Dictionary (2002).


                                                   2
[¶9] Mr. Johnson fell on April 11, 1997, injuring both knees and again on April 15,
1997, landing on a rock with his right knee. In 1998, Mr. Johnson received injections in
his knees to relieve the pain. He underwent bilateral knee surgeries on November 3,
1998, and Dr. Guier stated the “majority” of Mr. Johnson’s problems with both knees
related to the work injury. Mr. Johnson fell and injured his right knee again in 1999 and
underwent additional injections and another surgery on his right knee in 2000.

[¶10] During the 2000s, Mr. Johnson had carpel tunnel release surgery and was treated
for knee, back, shoulder and neck problems. Over the lengthy term of his medical
treatment, Mr. Johnson took a great deal of pain medication and his doctors expressed
concern over his pain medication use. In 2003, Mr. Johnson was seen by a pain
specialist, Tuenis Zondag, M.D., who noted he “lives with pain 24/7 and has multiple
areas with problems.”

[¶11] Despite his pain, Mr. Johnson worked in his fly fishing business and also returned
to welding in the mid 2000s. Finally, in 2009, Dr. Guier and Mr. Johnson requested
preauthorization from the Division to perform total knee replacement on both knees. The
Division issued final determinations denying both requests and also denying payment of
continued treatment of his knees by Dr. Zondag. The Division concluded the treatment
and total knee replacements were not associated with the 1992 work injury. Mr. Johnson
objected and the matters were consolidated for hearing. The Medical Commission issued
its decision on February 1, 2011, upholding the denial of benefits. Mr. Johnson filed a
petition for review with the district court, and the district court affirmed. He then filed a
timely notice of appeal to this Court.

                               STANDARD OF REVIEW

[¶12] Judicial review of an agency’s decision is governed by Wyo. Stat. Ann. § 16-3-
114(c) (LexisNexis 2013):

                (c) To the extent necessary to make a decision and when
              presented, the reviewing court shall decide all relevant
              questions of law, interpret constitutional and statutory
              provisions, and determine the meaning or applicability of the
              terms of an agency action. In making the following
              determinations, the court shall review the whole record or
              those parts of it cited by a party and due account shall be
              taken of the rule of prejudicial error. The reviewing court
              shall:
                     (i) Compel agency action unlawfully withheld or
              unreasonably delayed; and
                     (ii) Hold unlawful and set aside agency action,
              findings and conclusions found to be:


                                             3
                        (A) Arbitrary, capricious, an abuse of discretion
             or otherwise not in accordance with law;
                        (B) Contrary to constitutional right, power,
             privilege or immunity;
                        (C) In excess of statutory jurisdiction, authority or
             limitations or lacking statutory right;
                        (D) Without observance of procedure required by
             law; or
                        (E) Unsupported by substantial evidence in a case
             reviewed on the record of an agency hearing provided by
             statute.

In accordance with § 16-3-114(c), we review the agency’s findings of fact by applying
the substantial evidence standard. Dale v. S & S Builders, LLC, 2008 WY 84, ¶ 22, 188
P.3d 554, 561 (Wyo. 2008). Substantial evidence means “such relevant evidence as a
reasonable mind might accept as adequate to support a conclusion.” Bush v. State ex rel.
Wyo. Workers’ Comp. Div., 2005 WY 120, ¶ 5, 120 P.3d 176, 179 (Wyo. 2005) (citations
omitted). Findings of fact are supported by substantial evidence if, from the evidence
preserved in the record, we can discern a rational premise for the findings. Id.

[¶13] With regard to an agency determination that the claimant did not satisfy his burden
of proof, we have said:

             If the hearing examiner determines that the burdened party
             failed to meet his burden of proof, we will decide whether
             there is substantial evidence to support the agency’s decision
             to reject the evidence offered by the burdened party by
             considering whether that conclusion was contrary to the
             overwhelming weight of the evidence in the record as a
             whole. See, Wyo. Consumer Group v. Public Serv. Comm’n of
             Wyo., 882 P.2d 858, 860-61 (Wyo. 1994); Spiegel, 549 P.2d
             at 1178 (discussing the definition of substantial evidence as
             “contrary to the overwhelming weight of the evidence”). If, in
             the course of its decision making process, the agency
             disregards certain evidence and explains its reasons for doing
             so based upon determinations of credibility or other factors
             contained in the record, its decision will be sustainable under
             the substantial evidence test. Importantly, our review of any
             particular decision turns not on whether we agree with the
             outcome, but on whether the agency could reasonably
             conclude as it did, based on all the evidence before it.




                                            4
Dale, ¶ 22, 188 P.3d at 561.

[¶14] The agency has discretion in ruling on the admissibility of evidence and we do not
interfere unless it abused its discretion. Greene v. State ex rel. Wyo. Board of
Chiropractic Examiners, 2009 WY 42, ¶ 9, 204 P.3d 285, 290 (Wyo. 2009). Discretion
generally means “sound judgment exercised with regard to what is right under the
circumstances and without doing so arbitrarily or capriciously. An abuse of discretion
[is] said to have occurred only when the decision shocks the conscience of the court and
appears to be so unfair and inequitable that a reasonable person could not abide it.”
Airtouch Comm. Inc. v. Dep’t of Revenue, 2003 WY 114, ¶ 55, 76 P.3d 342, 361 (Wyo.
2003), quoting Sinclair Oil Corp. v. Wyo. Public Service Comm’n, 2003 WY 22, ¶ 41, 63
P.3d 887, 901 (Wyo. 2003) (other citations omitted). See also Clark v. State ex rel. Wyo.
Workers’ Safety & Comp. Div., 968 P.2d 436, 439 (Wyo. 1998).

[¶15] Even if an agency errs in ruling on an evidentiary issue, we must consider whether
its overall decision was arbitrary and capricious, i.e., whether it prejudiced a party’s
substantial rights, warranting reversal. Greene, ¶ 11, 204 P.3d at 290. We review an
agency’s conclusions of law de novo and will affirm if the agency’s conclusions are in
accordance with the law. Moss v. State ex rel. Wyo. Workers’ Comp. Div., 2010 WY 66, ¶
11, 232 P.3d 1, 4 (Wyo. 2010).

                                        DISCUSSION

      1. Admission of Evidence

[¶16] Mr. Johnson challenges the Medical Commission’s admission of three exhibits
into evidence over his objection. He claims the exhibits were not admissible because
they were irrelevant and unreliable. Wyo. Stat. Ann. § 16-3-108(a) (LexisNexis 2013)
addresses evidence in contested cases:

             In contested cases irrelevant, immaterial or unduly repetitious
             evidence shall be excluded and no sanction shall be imposed
             or order issued except upon consideration of the whole record
             or such portion thereof as may be cited by any party and
             unless supported by the type of evidence commonly relied
             upon by reasonably prudent men in the conduct of their
             serious affairs.

[¶17] At the beginning of the contested case hearing, the Medical Commission’s hearing
officer addressed the parties’ proposed exhibits. Mr. Johnson’s attorney objected to three
of the Division’s exhibits as irrelevant and unreliable: 1) a 1997 certificate of lien for
sales tax due to the State of Wyoming from Bennie C. Johnson, dba Highland Desert


                                            5
Flies; 2) the first page of a 2005 civil complaint in which Mr. Johnson, doing business as
Bennie’s Welding and Fabrication, was named as a defendant in a breach of contract and
slander case; and 3) an anonymous letter to the Division claiming that Mr. Johnson was
taking advantage of the worker’s compensation system. The State responded that the
exhibits were offered for the following reasons: “[T]he first two, go to credibility and
also to work history. The last exhibit . . . was received by the Division and became part
of the Division file. And to the extent for what it’s worth, it’s submitted for that
purpose.” The hearing officer stated the exhibits were of “questionable relevance or
persuasive value.” Nevertheless, he admitted all three, stating that he would “allow the
medical hearing panel to determine what particular weight, if any, is associated with
those particular exhibits.” The exhibits were never mentioned again, either by the parties
at the hearing or in the Medical Commission’s decision.

[¶18] The first two exhibits pertained to Mr. Johnson’s work history. The sales tax lien
was directed toward Mr. Johnson’s fly fishing business and showed that he was involved
in that business in 1997. The civil complaint confirmed that Mr. Johnson was engaged in
a welding business in 2005. In fact, Mr. Johnson testified that he worked as a fishing
guide in 1997, and he later worked in his own welding business. Mr. Johnson’s work
history was, undoubtedly, relevant in determining what caused his knee problems and
whether they were work related. The admission of the exhibits to establish his work
history was, therefore, reasonable.3

[¶19] On the other hand, the Division did not demonstrate the anonymous letter is the
type of evidence a reasonable person would rely upon in conducting his serious affairs.
Compare, Gray v. State ex rel. Wyo. Workers’ Safety & Comp. Div., 2008 WY 115, ¶ 15,
193 P.3d 246, 251 (Wyo. 2008), stating that while it may not have been error to admit an
anonymous statement into evidence at an agency hearing, it could not, alone, provide the
basis for a reasonable decision. No witness was questioned about the letter and the only
rationale given for its admission was that it was part of the Division file. Without more
justification as to the letter’s admissibility, the agency erred when it allowed it into
evidence.

[¶20] Nevertheless, the error is not reversible unless it prejudiced Mr. Johnson, resulting
in an arbitrary and capricious decision. See Greene, ¶ 11, 204 P.3d at 290. In resolving
the compensability issue, the Medical Commission primarily focused on the medical
evidence. The letter was not part of that evidence, and the Medical Commission did not
even mention the letter in its decision. In Walton v. State ex rel. Wyo. Workers’ Safety &
Comp. Div., 2007 WY 46, ¶ 37, 153 P.3d 932, 940-41 (Wyo. 2007), we stated that it was
improper for the Medical Commission to conduct its own neurological examination of the
3
  With regard to the Division’s assertion that the exhibits were admissible on the issue of Mr. Johnson’s
credibility, it is difficult to understand how either of the exhibits would have proven or disproven that he
was credible. As we stated earlier, the exhibits were not discussed at the hearing so there was no context
for them.


                                                     6
claimant at the hearing, but, given there was no indication it relied on the examination in
reaching its decision, reversal was not required. Here, too, the error was harmless and
reversal is not warranted. See Grams v. Environmental Quality Council, 730 P.2d 784,
787 (Wyo. 1986).

        2. Causation

[¶21] The Medical Commission concluded Mr. Johnson failed to prove his need for
bilateral knee replacement and continued treatment of his knees was related to the 1992
injury. A worker’s compensation claimant has the burden of proving each of the
essential elements of his claim by a preponderance of the evidence. Kenyon v. State ex
rel. Wyo. Workers’ Safety & Comp. Div., 2011 WY 14, ¶ 22, 247 P.3d 845, 851 (Wyo.
2011). “As a part of that burden, the claimant must prove a causal connection exists
between a work-related injury and the injury for which worker’s compensation benefits
are being sought.” Dale, ¶ 35, 188 P.3d at 563. The requirement of a causal connection
is included in the statutory definition of injury in Wyo. Stat. Ann. § 27-14-102(a)(xi)
(LexisNexis 2012):

                       (xi) “Injury” means any harmful change in the human
                organism other than normal aging and includes damage to or
                loss of any artificial replacement and death, arising out of and
                in the course of employment while at work in or about the
                premises occupied, used or controlled by the employer and
                incurred while at work in places where the employer’s
                business requires an employee’s presence and which subjects
                the employee to extrahazardous duties incident to the
                business.

See also Huntington v. State ex rel. Wyo. Workers’ Safety & Comp. Div., 2007 WY 124, ¶
10, 163 P.3d 839, 842 (Wyo. 2007). Thus, to satisfy the causation element, Mr. Johnson
was required to show a nexus between the condition for which benefits were sought and
an activity at work. Id. Physical conditions associated with the normal aging process are
specifically excluded from the definition of injury. Section 27-14-102(a)(xi).

[¶22] Mr. Johnson presents two arguments challenging the Medical Commission’s
decision that he did not meet his burden of proving the 1992 work injury necessitated
bilateral knee replacements.4 First, he claims the commission incorrectly ruled in Finding
of Fact No. 3 that the 1992 injury to his knees was a single injury rather than a
cumulative trauma. Finding of Fact No. 3 states in pertinent part:
4
 Although it may be applicable, Mr. Johnson does not address the “second compensable injury” rule.
This distinction is not important, however, because the ultimate question is whether his current treatment
was causally connected to the original injury. See Hoffman v. State ex rel. Wyo. Workers’ Safety &
Comp. Div., 2012 WY 164, ¶ 9, 291 P.3d 297, 301-02 (Wyo. 2012).


                                                    7
                     Shortly after receiving Dr. Guier’s letter the Division
              issued a letter dated January 26, 1993, which found that Mr.
              Johnson had sustained an injury while he was an employee of
              TIC The Industrial Company, Wyoming, Inc., (also referred
              to as “TIC”), out of Casper, Wyoming, on September 23,
              1992. The Final Determination letter in question, submitted
              as Employee/Claimant’s Exhibit EC 14-1, is silent on the
              issue of “cumulative trauma injury”, but rather clearly
              indicates that the date of the injury was to be considered as
              September 23, 1992, which is the date of the first medical
              visit Mr. Johnson had with Dr. Guier.

[¶23] Throughout the proceedings in this case, Mr. Johnson referred to the 1992 injury
as a “cumulative trauma” injury, presumably meaning an injury which occurs over a
substantial period of time under Wyo. Stat. Ann. § 27-14-603(a) (LexisNexis 1991):

                     (a) The burden of proof in contested cases involving
              injuries which occur over a substantial period of time is on
              the employee to prove by competent medical authority that
              his claim arose out of and in the course of his employment
              and to prove by a preponderance of evidence that:
                          (i) There is a direct causal connection between the
              condition or circumstances under which the work is
              performed and the injury;
                         (ii) The injury can be seen to have followed as a
              natural incident of the work as a result of the employment;
                        (iii) The injury can fairly be traced to the
              employment as a proximate cause;
                        (iv) The injury does not come from a hazard to
              which employees would have been equally exposed outside
              of the employment; and
                        (v) The injury is incidental to the character of the
              business and not independent of the relation of employer and
              employee.

[¶24] Dr. Guier’s letter to the Division which was referenced in Finding of Fact No. 3
was dated January 5, 1993. In that letter, Dr. Guier did not mention Mr. Johnson’s earlier
fall but, instead, stated: “Bennie’s injuries to both knees were secondary to chronic stress
placed on the knees from long-term use in his occupation and kneeling on his knees.”
As the Medical Commission pointed out in Finding of Fact No. 3, the Division did not
describe the injury as “cumulative” or one occurring over a substantial period of time in
its 1993 initial review allowing coverage. That factual finding does not, however,


                                             8
represent the Medical Commission’s ultimate conclusion. Instead, the Medical
Commission’s decision repeatedly refers to Mr. Johnson’s 1992 injury as involving
cumulative trauma. In fact, the commission concluded that Mr. Johnson’s 1992 injury
necessarily included “all prior knee injury pathology.” The Medical Commission’s
decision correctly described the nature of the injury as reflected in the record.

[¶25] Mr. Johnson’s second challenge to the Medical Commission’s decision is that it
erred by rejecting Dr. Guier’s opinion that his need for bilateral total knee replacements
related to the 1992 compensable injury. The Medical Commission has special medical
expertise in worker’s compensation cases involving complex medical issues. Hathaway
v. State ex rel. Wyo. Workers’ Safety & Comp. Div., 2014 WY 12, ¶ 25, 317 P.3d 590,
596 (Wyo. 2014), citing Stallman v. State ex rel. Wyo. Workers’ Safety & Comp. Div.,
2013 WY 28, ¶ 28, 297 P.3d 82, 90 (Wyo. 2013). As the fact-finder in a contested case
hearing, the Medical Commission must parse available medical records and testimony
and determine the weight of the available evidence. Id. This includes weighing of expert
medical opinions. The agency “‘is entitled to disregard an expert opinion if [it] finds the
opinion unreasonable, not adequately supported by the facts upon which the opinion is
based, or based upon an incomplete and inaccurate medical history provided by the
claimant.’” Watkins v. State ex rel. Wyo. Workers’ Safety & Comp. Div., 2011 WY 49, ¶
25, 250 P.3d 1082, 1090-91 (Wyo. 2011), quoting Taylor v. State ex rel. Wyo. Workers’
Safety & Comp. Div., 2005 WY 148, ¶ 15, 123 P.3d 143, 148 (Wyo. 2005).

[¶26] Dr. Guier was Mr. Johnson’s orthopedic specialist for many years. His records
were admitted into evidence and he was deposed several times over the years. The most
recent deposition of Dr. Guier occurred in 2010 as part of the contested case proceeding
at issue here. Dr. Guier stated that he started seeing Mr. Johnson in 1992 and explained
the nature of his initial complaints as:

                    “[H]e was a 35 year old male who ha[d] a long
             standing history of pain in both of his knees, that he had
             fallen approximately 30 feet onto the front of his knees in
             1985, and that he had been treated conservatively and that he
             had noted some weakness and giving way of his legs, but no
             catching or locking.”

Dr. Guier diagnosed Mr. Johnson’s knee problems as: “chondromalacia [abnormality in
the cartilage] in both patellofemoral joints as well as patellar tendinitis.” Although he
focused primarily on Mr. Johnson’s right knee, he suggested that the 1992 work injury
had caused the condition which required both of Mr. Johnson’s knees to be replaced.

[¶27] The Medical Commission rejected Dr. Guier’s opinion on causation because it was
inconsistent with testimony he had given in 1999, in which he relied heavily upon a “fall”
that occurred in 1992, when no such fall had taken place. The Medical Commission


                                            9
pointed out that Mr. Johnson’s fall had actually occurred in 1986, and he had only
reported an injury to his shoulder, not to his knees. Dr. Guier’s 1999 testimony
concerning the onset of Mr. Johnson’s knee problems was different than his testimony in
2010:

             Bennie’s occupation at the time that I first saw him was as a
             welder, and he described the job to me as a job that required
             him to get into a stooped and squatted and sometimes a
             kneeling position, awkward position, to get into these pipes to
             weld them. And then he apparently fell 30 feet is what my
             records show directly onto both knees.

So, in 1999, Dr. Guier believed that Mr. Johnson had stressed his knees while welding
and then had fallen shortly before his first appointment in 1992.

[¶28] By the time Dr. Guier’s deposition was taken in 2010, Mr. Johnson had informed
the doctor that his understanding of the history of his knees problems was mistaken, i.e.
that the fall had occurred several years before his first appointment. Consequently, Dr.
Guier testified in 2010, that Mr. Johnson had fallen in 1986, which caused the initial
damage to his knees and he then further stressed the joints while welding. Under both
scenarios, Dr. Guier opined, Mr. Johnson’s work activities caused his degenerative knee
problems. Because of Dr. Guier’s incomplete and shifting understanding of the nature of
Mr. Johnson’s injury, the Medical Commission concluded that it could not rely on Dr.
Guier’s opinion as to causation. Given the inconsistencies in Dr. Guier’s testimony, it
was reasonable for the Medical Commission to discount his opinion. In accordance with
our standard of review, when an agency explains its reasons for disregarding certain
evidence based upon factors contained in the record, its decision will be sustainable under
the substantial evidence test. Dale, ¶ 22, 188 P.3d at 561.

[¶29] The inconsistencies in Dr. Guier’s explanation of Mr. Johnson’s injury were not
the only grounds for the Medical Commission’s decision to disregard Dr. Guier’s
testimony and conclude that Mr. Johnson had not met his burden of proof. The
commission stated that the initial surgery performed by Dr. Guier in 1992 was a simple
“clean up” procedure involving a bilateral knee arthroscopy and chondral debridement
for the chondromalacia patellae and a partial synovectomy. It noted that he was released
within a few weeks to resume his normal activities. After that, he continued to suffer
from pain and Dr. Guier recommended he quit the welding profession, which he did. The
Medical Commission found:

              [O]nce Mr. Johnson was removed from the welding
             profession, which had caused the ‘cumulative trauma injury’
             to his knees, his knees returned to a baseline level of function,
             and subsequent pathology was caused by ongoing falls,


                                            10
             normal aging and continued degeneration of the knees,
             exacerbated by his obesity, and the serious pedestrian/motor
             vehicle accident.”

The agency further ruled:

                     This Panel finds and concludes that the original 1992
             “cumulative trauma injury” was minor in nature, and is a
             common condition seen in an aging population that is treated
             by simple arthroscopic surgical procedures, and in and of
             itself does not lead to a total knee replacement procedure.
             Mr. Johnson has failed to provide credible evidence that the
             need for bilateral total knee replacements and ongoing
             medical care to his knees is directly or causally related to the
             1992 “cumulative trauma injury”, and the same are therefore
             found to be non-compensable.

[¶30] The Medical Commission’s rulings are supported by the record. Mr. Johnson’s
right knee was seriously injured in 1993 in a pedestrian/motor vehicle accident.
Although Dr. Guier stated the accident did not precipitate Mr. Johnson’s need for
replacement of his right knee, several independent medical examinations performed after
the accident indicated otherwise. In addition, a different panel of the Medical
Commission ruled in 1997 that the condition of his right knee at that time was not due to
the 1992 cumulative trauma injury, but was caused by the pedestrian/motor vehicle
accident. Based upon this evidence, the Medical Commission stated in the current action:
“This Panel . . . finds that these advanced degenerative changes in the right knee are
entirely consistent with the damage sustained in the pedestrian/motor vehicle accident,
and are the cause of the need of the total right knee replacement procedure.” (emphasis in
original). Substantial evidence supports this finding.

[¶31] Without providing many details, Dr. Guier also suggested that Mr. Johnson needed
a left knee replacement because of the 1992 injury. Addressing the left knee, the Medical
Commission stated that an MRI study completed on November 9, 2009, showed Mr.
Johnson’s current left knee problem was different from the problem he had in 1992. The
commission stated:

             [T]hese degenerative conditions are primarily noted on
             components of the left knee that were not the primary
             components of the 1992 ‘cumulative trauma injury’, which
             consisted of damage under the patella and chondromalacia,
             with a small meniscal tear that was repaired in May of 199[3].
             The current findings are consistent with a knee that has
             simply degenerated with the passage of time, prompted by


                                            11
             new falls and stumbles in his new profession, and general
             living and overall aging, which are exacerbated and
             accelerated by his obesity.

The MRI report supports the Medical Commission’s conclusion.

[¶32] Dr. Guier also did not adequately explain the effect of other factors on Mr.
Johnson’s knee condition. In particular, the doctor did not thoroughly discuss the
ramifications of several falls in the late 1990s and 2000s. In Huntington, ¶ 13, 163 P.3d
at 844, we noted that the agency is entitled to disregard a medical opinion when the
doctor failed to account for intervening injuries. In addition, Mr. Johnson was obese and
the medical witnesses, including Dr. Guier, stated that extra body weight contributes to
knee problems.

[¶33] To recap, the knee injuries Dr. Guier saw Mr. Johnson for in 1992 were relatively
minor. Mr. Johnson underwent a simple surgical procedure to “clean up” the cartilage
under his knee caps, and was released to return to work shortly thereafter. Mr. Johnson’s
right knee was severely injured in 1993 when he was hit by a car. Following Dr. Guier’s
recommendation, Mr. Johnson quit welding and started a fly fishing business. However,
he fell several times while walking along the river, resulting in medical treatment for his
knees. For several years in the 2000s Mr. Johnson did not see Dr. Guier, but instead saw
pain specialist, Dr. Zondag, who treated him for various areas of pain. Finally in 2009,
seventeen years after his initial injury, Dr. Guier requested preauthorization from the
Division to perform total knee replacements on both knees. Although Dr. Guier asserted
Mr. Johnson’s knees needed to be replaced because of the 1992 work injury, his
understanding of the timing and nature of Mr. Johnson’s injuries shifted over time and he
failed to explain how the relatively minor cartilage condition led to the need for total
knee replacements. In addition, Dr. Guier’s opinions did not sufficiently eliminate the
intervening accidents, general aging and/or obesity as the cause of Mr. Johnson’s need
for bilateral total knee replacements.

[¶34] Mr. Johnson’s lengthy and complicated history of knee problems made
understanding the cause of the condition necessitating his total knee replacements
difficult. The Medical Commission’s expertise in understanding the medical issues is
entitled to respect. Hoffman, ¶ 23, 291 P.3d at 305; Stallman, ¶ 28, 297 P.3d at 90. Its
decision to disregard Dr. Guier’s testimony and conclude that Mr. Johnson had not met
his burden of proof was not against the overwhelming weight of the evidence. The
Medical Commission’s decision to reject the evidence offered by Mr. Johnson is,
therefore, supported by substantial evidence.

[¶35] Affirmed.




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