                 IN THE SUPREME COURT OF IOWA
                             No. 10–0795

                        Filed February 10, 2012


DONALD A. WESTLING,

      Appellant,

vs.

HORMEL FOODS CORPORATION,

      Appellee.


      On review from the Iowa Court of Appeals.



      Appeal from the Iowa District Court for Polk County, Carla T.

Schemmel, Judge.



      A worker appeals a decision of the workers’ compensation

commissioner finding that the worker’s claimed disability was not caused

by a work-related injury.   DECISION OF COURT OF APPEALS AND

JUDGMENT OF THE DISTRICT COURT AFFIRMED.


      Mark S. Soldat of Soldat & Parrish-Sams, P.L.C., West Des Moines,

for appellant.



      Valerie A. Landis of Hopkins & Huebner, P.C., Des Moines, for

appellee.
                                     2

WIGGINS, Justice.

      In this appeal, we must decide whether the workers’ compensation

commissioner correctly decided that a worker failed to prove his claimed

disability was causally related to a work injury. Because an award for

partial permanent disability for an unscheduled injury under Iowa Code

section 85.34(2)(u) (2005) is determined by industrial disability, rather

than by functional impairment, the commissioner used the correct

standard to determine the causal relation between the work injury and

the alleged disability.   Furthermore, substantial evidence supports the

commissioner’s findings.    Thus, we affirm the decision of the court of

appeals and the judgment of the district court.

      I. Background Facts and Proceedings.

      At the time of his arbitration hearing, Donald A. Westling was fifty-

nine years old.   He is a high-school graduate and worked for Hormel

Foods Corporation for thirty years and one day before voluntarily retiring

on November 24, 2006.       On January 5, 2006, Westling experienced a

sharp pain in his right shoulder while removing casings from meat

products using a strip-out machine. In addition, Westling experienced a

burning sensation and could not lift his arms above his head.           He

continued to experience pain while he worked.

      On February 16, Westling saw Dr. Ryan J. Thoreson, who

diagnosed his injury as a rotator cuff strain. After physical therapy did

not alleviate Westling’s pain, Westling saw Dr. Philip A. Deffer, an

orthopaedic surgeon, on March 31.        After an MRI exam suggested

Westling had a partial rotator cuff tear, Dr. Deffer referred Westling to

Dr. Jason C. Hough for surgery.

      Dr. Hough performed arthroscopic surgery on Westling’s right

shoulder on July 10.        During the surgery, Dr. Hough discovered
                                    3

significant fraying of the anterior and superior labrum as well as a large

spur along the acromion.       He also noted inflammation along the

subscapularis muscle. Dr. Hough did not discover a rotator cuff tear.

Dr. Hough removed the frayed labrum, part of the membrane covering

the acromion, the anterior acromion hook to the acromioclavicular joint,

and part of the subacromial bursa. He also freed the spur.

      One week later at his follow-up appointment, Westling reported

that he was “doing quite well.” Dr. Hough referred Westling to physical

therapy and told him to take four weeks off from work. Westling steadily

improved following the surgery, and one month after surgery, Westling

reported to his physical therapist that he did not have much pain. In

mid-August, Dr. Hough allowed Westling to return to full-duty work for

half of each day and light duty for the remainder. In mid-September,

Dr. Hough released Westling to full-duty work with no restrictions.

Although Westling’s condition had improved, he still experienced a

burning sensation and pain when he extended his right arm over his

head or performed pushing or pulling motions.

      On October 12, Dr. Hough wrote to a Hormel representative

regarding Westling’s shoulder. Dr. Hough expressed his opinion that the

surgery did not cause Westling to have a permanent impairment.         He

wrote,

      In regard to Donald Westling’s shoulder, I do not believe that
      he will have any permanent impairment secondary to his
      surgical intervention. I believe that he has done quite well
      and he should not have any impairment secondary to this.

      Westling retired on November 24. No doctor advised him to retire,

and he did so voluntarily.     After retiring, Westling divided his time

between Iowa and Florida and did not look for other permanent
                                    4

employment, although he occasionally painted a house or mowed his

neighbor’s lawn in exchange for money.

      On March 15, 2007, Westling filed a petition with the Iowa

workers’ compensation commissioner. Westling alleged he suffered the

injury to his shoulder while working at Hormel and that “[c]umulatively

and gradually, overuse syndrome developed into an impingement

syndrome” resulting in permanent disability. Hormel admitted Westling

sustained a work-related injury on January 5, 2006, which caused a

temporary disability, but disputed that Westling’s injury caused a

permanent disability.

      On April 9, 2008, at Westling’s request, Dr. Mary A. Shook

performed an independent medical examination of Westling’s shoulders.

Westling reported to Dr. Shook that his pain level was an eight on a ten-

point scale. In her report, Dr. Shook attributed Westling’s then-current

pain in his right shoulder to arthritis and not overuse. She also opined

that any pain in Westling’s left shoulder was probably related to arthritis

and not stemming from overuse during his employment at Hormel.

Dr. Shook explained,

      Review of records referring to the right shoulder indicates
      arthritis diagnosed at the time of surgery. It is even noted
      that a rotator cuff tear had healed . . . . Arthritis is also
      noted in the knees and neck. I suspect arthritis is present in
      the left shoulder as well. Although Hormel is noted to be a
      physically demanding workplace, the patient describes a
      number of jobs he has been assigned to, not the same job
      over a number of years. Review of records also indicates
      many months of limited duty or no duty related to injury
      care and recuperation from surgical procedures . . . .
      Repetitive motion injury because of work assignments is best
      diagnosed in relationship to actual tasks performed. Since
      Mr. Westling retired in November, 2006 there has been no
      recent repetitive motion at the workplace. Thus I can safely
      conclude that his current symptoms are NOT from repetitive
      tasks due to work assignments. Any current exacerbation of
                                        5
      pain in the shoulders would more likely be related to recent
      use not prior work use. Arthritis causes increased pain and
      decreased function over time. With a reasonable degree of
      medical certainty, his current shoulder complaints are due
      to arthritis, not cumulative trauma.

      Using range of motion as the criteria, Dr. Shook evaluated Westling

as having two percent whole person impairment for the right shoulder

and three percent whole person impairment for the left shoulder, both

caused by arthritis and not Westling’s work activities. Dr. Shook rated

Westling’s impairment in accordance with the fifth edition of the

American Medical Association’s Guides to the Evaluation of Permanent
Impairment.

      Following an arbitration hearing in September, the deputy workers’

compensation commissioner determined Westling failed to establish “a

causal relationship between his January 5, 2006 injury and his claimed

permanent disability.”   The deputy commissioner credited Dr. Hough’s

opinion that Westling did not have any permanent impairment of his

right shoulder because of the surgery and Dr. Shook’s opinion that

Westling did not have any permanent impairment because of overuse

while working for Hormel.     On appeal, the commissioner affirmed and

adopted the deputy’s decision.

      Westling sought rehearing, arguing the commissioner needed to

decide “whether for the purposes of Iowa Code section 85.34(2), the

definition of permanent impairment contained in the A.M.A. Guides to the

Evaluation of Permanent Impairment, was synonymous with the judicial

definition of functional disability.”       In denying Westling’s request for

rehearing, the commissioner stated,

      While claimant cites numerous errors alleged in the agency
      decision, he more particularly cited to the need for the
      agency to address its definition of impairment. The core of
      claimant’s argument is that it was in error for the agency to
                                    6
      determine he had sustained no permanent impairment
      despite the surgical procedure of July 10, 2006, a procedure
      that claimant describes in near-complete detail. Claimant’s
      argument that such a procedure would result in some
      impairment, however minor, is persuasive.

Nevertheless, the commissioner found that

      [t]he presiding deputy, and the undersigned on appeal, relied
      upon undisputed medical evidence that claimant’s work was
      not a cause of a permanent bilateral shoulder condition. The
      medical opinions were convincing and supported the
      conclusion that claimant had not sustained permanent
      impairment or disability resulting from his work. Claimant
      failed to provide sufficient proof of permanent impairment,
      despite a persuasive argument upon the limited proof
      included in the record of this case.

The commissioner concluded Westling failed to establish either a

permanent physical impairment or permanent disability caused by the

January 5, 2006 injury.

      Westling filed a petition for judicial review. The district court saw

some merit in Westling’s argument that the surgery may have resulted in

some permanent impairment under the Guides’ definition of impairment,

but concluded the commissioner did not make an error of law in making

a contrary finding. The district court noted the opinions of Drs. Shook

and Hough were “uncontroverted, well-supported medical evidence . . .

that Westling’s work-related injury and resultant surgery was not a

cause of a permanent impairment or disability.”

      The court    of appeals affirmed the        district court and the

commissioner. Westling requested further review, which we granted.

      II. Scope of Review.

      We review an appeal of a workers’ compensation decision under

the standards set forth in chapter 17A of the Iowa Code. Xenia Rural

Water Dist. v. Vegors, 786 N.W.2d 250, 252 (Iowa 2010). We apply the
                                         7

standards “to determine whether the conclusions we reach are the same

as those of the district court.” Andover Volunteer Fire Dep’t v. Grinnell

Mut. Reins. Co., 787 N.W.2d 75, 79 (Iowa 2010). If we reach the same

conclusion as the district court, we affirm, but if we reach a different

conclusion, we reverse. Id.

       We defer to the agency’s interpretation of a statute when the

legislature has clearly vested the agency with the authority to interpret a

statute.    Renda v. Iowa Civil Rights Comm’n, 784 N.W.2d 8, 11 (Iowa

2010).     When the legislature has clearly vested the agency with such

authority, we “will only reverse a decision of statutory construction which

is irrational, illogical, or wholly unjustifiable.” Xenia, 786 N.W.2d at 252;

see also Iowa Code § 17A.19(10)(l).          If, however, the agency has not

clearly been vested with such authority, we review questions of statutory

interpretation for correction of errors at law. Xenia, 786 N.W.2d at 252;

see also Iowa Code § 17A.19(10)(c).

       In this case, we are reviewing the commissioner’s interpretation of

Iowa Code section 85.34(2), which deals with permanent partial disability

compensation. An examination of chapter 85 does not reveal any basis

for   concluding    that   the    legislature   clearly     vested    the   workers’

compensation commissioner with authority to interpret the subsection at

issue. Therefore, we review the commissioner’s statutory interpretation

for correction of errors at law. See Iowa Code § 17A.19(10)(c).

       When a claim is made that the commissioner’s decision is not

based upon substantial evidence, we must determine if a factual

determination      made    by    the   commissioner       “is   not   supported   by

substantial evidence in the record before the court when that record is

viewed as a whole.” Id. § 17A.19(10)(f). Merely because we may draw

different conclusions from the record does not mean the evidence is
                                      8

insubstantial.     Arndt v. City of Le Claire, 728 N.W.2d 389, 393 (Iowa

2007).

      III. Discussion and Analysis.

      A.     Determining Permanent Disabilities Generally.            Westling

contends that the commissioner erred in finding no physical impairment

resulted from the injury in this case and that this erroneous finding also

rendered erroneous the determination that no permanent disability

resulted. Westling notes the definition of permanent impairment in the

Guides      includes   permanent   derangement      of    bodily   structures.

Contending it is indisputable that the agency record established his

shoulder surgery resulted in permanent derangement of the structures in

and around his shoulder, Westling posits the commissioner could not

find, on this record, that no permanent physical impairment resulted

from the injury.

      Iowa Code section 85.34 governs the award of compensation for

permanent      disabilities.    Specifically,   section    85.34(2)   governs

compensation for permanent partial disabilities.          Sections 85.34(2)(a)

through (t) govern permanent partial disability payments for scheduled

injuries.   St. Luke’s Hosp. v. Gray, 604 N.W.2d 646, 653 (Iowa 2000).

The commissioner determines the compensation for scheduled injuries

based on the impairment of an injured worker’s body function. Mortimer

v. Fruehauf Corp., 502 N.W.2d 12, 15 (Iowa 1993).             In making this

determination, the commission’s rules allow the commissioner to use the

Guides. Iowa Admin. Code r. 876—2.4. The rule states:

            The Guides to the Evaluation of Permanent
      Impairment, Fifth Edition, published by the American
      Medical Association are adopted as a guide for determining
      permanent partial disabilities under Iowa Code section
      85.34(2) “a” to “s.” The extent of loss or percentage of
      permanent impairment may be determined by use of the
                                      9
      Fifth Edition of the guides and payment of weekly
      compensation for permanent partial scheduled injuries made
      accordingly. Payment so made shall be recognized by the
      workers’ compensation commissioner as a prima facie
      showing of compliance by the employer or insurance carrier
      with the foregoing sections of the Iowa workers’
      compensation Act. Nothing in this rule shall be construed to
      prevent the presentations of other medical opinions or
      guides or other material evidence for the purpose of
      establishing that the degree of permanent disability to which
      the claimant would be entitled would be more or less than
      the entitlement indicated in the Fifth Edition of the AMA
      guides.

Id.

      The Guides are not conclusive evidence on the extent of permanent

impairment. Lauhoff Grain Co. v. McIntosh, 395 N.W.2d 834, 839 (Iowa

1986). The agency’s rule specifically allows the commissioner to consider

other competent medical evidence when determining the percentage of

partial permanent disability resulting from a scheduled injury. See Iowa

Admin. Code r. 876—2.4. The commissioner does not consider loss of

earning capacity in determining a partial permanent disability for a

scheduled member.        Mortimer, 502 N.W.2d at 15.         Thus, in a case

involving a scheduled injury, if there is a causal connection between a

work-related injury and a functional impairment, the statute allows the

commissioner to find a partial permanent disability.

      The legislature devised a different standard for determining the

extent of partial permanent disability for unscheduled injuries.            When

determining    the    extent   of   permanent   disability      resulting   from

unscheduled injuries, the commissioner must assess whether the injury

diminished    the    injured   worker’s   earning   capacity.       Iowa    Code

§ 85.34(2)(u). The Code provides:

      In all cases of permanent partial disability other than those
      hereinabove described or referred to in paragraphs “a”
      through “t” hereof, the compensation shall be paid during
      the number of weeks in relation to five hundred weeks as the
                                     10
       reduction in the employee’s earning capacity caused by the
       disability bears in relation to the earning capacity that the
       employee possessed when the injury occurred.

Id.

       We have referred to the reduction in earning capacity as “industrial

disability.” McSpadden v. Big Ben Coal Co., 288 N.W.2d 181, 192 (Iowa

1980). In determining industrial disability, the commissioner must look

at the injured worker’s “age, education, qualifications, experience and his

inability, because of the injury, to engage in employment for which he is

fitted.”    Olson v. Goodyear Serv. Stores, 255 Iowa 1112, 1121, 125

N.W.2d 251, 257 (1963). The commissioner also considers the claimant’s

functional impairment in determining the extent of industrial disability.

Mortimer, 502 N.W.2d at 14; Simbro v. Delong’s Sportswear, 332 N.W.2d

886, 887 (Iowa 1983). Although functional disability is a factor in the

determination of work-related industrial disability, it is not a conclusive

factor. McSpadden, 288 N.W.2d at 192. Thus, proof of an unscheduled

injury alone will not support an award of partial permanent disability.

The claimant must prove the work-related injury caused an industrial

disability.

       B. Westling’s Partial Permanent Disability Claim. As we have

noted, Westling contends that he conclusively proved the shoulder

surgery       caused   permanent   physical   impairment   and   that    the

commissioner’s finding to the contrary is not supported by substantial

evidence.      He bases his contention on the premise that the Guides

defines “impairment” to include an anatomical derangement of the body.

Believing the commissioner erred in finding no work-related physical

impairment, Westling further contends the commissioner’s determination

that the injury caused no industrial disability must also be reversed.
                                   11

      Westling’s arguments on appeal fail for two reasons.      First, the

record did not conclusively establish that the shoulder surgery caused

permanent physical impairment. The evidence on this issue was mixed.

Although the surgeon’s surgical note provides evidence that structures in

Westling’s shoulder were removed and permanently altered, this evidence

did not stand alone. The record also contains the surgeon’s opinion that

Westling did not suffer any permanent physical impairment because of

the surgery and the opinion of the physician who performed the

independent medical examination who opined Westling did not suffer any

permanent impairment because of overuse while working for Hormel. As

the Guides are not conclusive evidence as to the definition of permanent

physical impairment or the extent of impairment, the commissioner did

not err in finding on this record that Westling failed to prove permanent

physical impairment resulting from the injury.

      The second reason Westling’s argument on appeal must fail is that

he failed to establish that the commissioner erred in finding the work-

related injury did not cause industrial disability. Even if Westling had

proved to the satisfaction of the commissioner that the structural

derangement of the shoulder resulting from the surgery caused a

permanent physical impairment, it would have been to no avail.        The

commissioner’s separate determination that the work-related injury

produced no loss of earning capacity was supported by substantial

evidence.

      Our review of the record leads us to the same conclusion reached

by the court of appeals.   It is not the role of the district court or the

appellate courts to reweigh the evidence. Arndt, 728 N.W.2d at 394–95.

      Westling raises further issues on appeal. We need not reach these

issues because his further issues depend on us accepting his claim that
                                    12

the commissioner erred when he failed to find a causal relation between

Westling’s January 5, 2006 injury and his claimed disability.

      IV. Disposition.

      We agree with the district court and the court of appeals that the

commissioner did not err in determining Westling suffered no permanent

physical impairment or permanent disability as a consequence of a work-

related injury. Therefore, we affirm the decision of the court of appeals

and the judgment of the district court.

      DECISION OF COURT OF APPEALS AND JUDGMENT OF THE

DISTRICT COURT AFFIRMED.

      All justices concur except Mansfield, J., who takes no part.
