Larson Manufacturing Company, Inc., And Atlantic Mutual Companies Vs. Julie Thorson

IN THE SUPREME COURT OF IOWA
No. 06–1954

Filed February 13, 2009

LARSON MANUFACTURING COMPANY, INC.,
and ATLANTIC MUTUAL COMPANIES,

Appellants,

vs.

JULIE THORSON,

Appellee.

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

Schemmel, Judge.

Employer and its insurance carrier appeal from the district court’s

decision affirming a decision of the workers’ compensation commissioner.

AFFIRMED IN PART AND REVERSED IN PART.

Jeffrey W. Lanz of Huber, Book, Cortese, Happe & Lanz, P.L.C.,
West Des Moines, for appellants.

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

for appellee.
 2

HECHT, Justice.

We reversed and remanded this case to the workers’ compensation

commissioner in Thorson v. Larson Mfg. Co., 682 N.W.2d 448, 451 (Iowa

2004).1 After the parties submitted additional evidence on remand, the
commissioner found Thorson sustained a compensable cumulative

injury, and ordered the employer and its insurance carrier to pay

compensation, interest, medical expenses, and the cost of a medical

examination under Iowa Code section 85.39 (2005). On judicial review,

the district court affirmed the commissioner’s remand decision. We

affirm in part and reverse in part the commissioner’s decision.

I. Factual and Procedural Background.

Julie Thorson began working for Larson Manufacturing Company,

Inc.,2 a storm door manufacturer in Lake Mills, Iowa in 1974. Her job

duties evolved over the years, but consistently involved continuous,

repetitive movement and occasionally required overhead work. For

approximately the first twenty years of her employment, Thorson’s job

1The arbitration decision had excluded the report of Dr. Justin Ban (offered by
Thorson and asserting she sustained a permanent cumulative injury to her shoulders,
upper extremities, and cervicothoracic spine) on the ground it was not served within the
deadline established in a hearing assignment order. The decision awarded
compensation for Thorson’s lower extremity injury, but determined Thorson failed to
prove she sustained a compensable cumulative injury. On judicial review, the district
court reversed and remanded to the commissioner for application of the manifestation
standard discussed in our decision in Herrera v. IBP, Inc., 633 N.W.2d 284, 288 (Iowa
2001) (establishing that a cumulative injury is manifest when “the claimant, as a
reasonable person, would be plainly aware (1) that he or she suffers from a condition or
injury, and (2) that this condition or injury was caused by the claimant’s employment”)
and directed the commissioner to consider Dr. Ban’s report only to the extent that it
rebutted certain medical evidence offered by the employer. On appeal, we reversed the
commissioner’s decision and remanded to the agency for “reconsideration of [Thorson’s]
claim on the record already made, with the addition of the Ban report and any rebuttal
evidence that the commissioner allows.” Thorson v. Larson Mfg. Co., 682 N.W.2d at 451.

2Atlantic Mutual Companies provided workers’ compensation insurance
coverage to Larson during times at issue in this case. In the interest of brevity, we will
refer jointly to Larson and Atlantic as “Larson.”
 3

duties required her to perform the same repetitive physical tasks for

eight hours each day. In 1995 or 1996, Larson implemented a job

rotation program which allowed employees to change their work station

each day. The program was later modified to allow Thorson and other

employees to change stations after each half-day of work.

Thorson first sought treatment for neck and shoulder pain in 1986

from Dr. Ronald Masters, a chiropractor, who offered a free clinic for
patients. Thorson discontinued chiropractic treatments after four

months, however, when free services were no longer offered because her

health insurance did not provide coverage for chiropractic care.

Thorson next received relevant medical care in August 1992 when

Larson referred her to Dr. Colby, a family physician, for diagnosis and

treatment of shoulder and wrist symptoms. Dr. Colby diagnosed lateral

epicondylitis, and placed Thorson on light duty until October 28, 1992,

when she was released to full duty with no physician-imposed physical

restrictions.

Thorson again consulted Dr. Colby for work-related pain on

April 26, 1996. Thorson reported she had been experiencing “knots” in

her lower back, shoulders, and elbows for the past eighteen months.
Dr. Colby diagnosed back spasms and medial epicondylitis, and again

placed Thorson on light duty. Although Thorson was informed no real

light-duty jobs were available, Larson did assign her to a job requiring

less exertion than her usual work assignments. Dr. Colby referred

Thorson to Dr. Toth for physical therapy in July 1996.

Dr. Toth diagnosed chronic cervical and thoracic spine strain with

somatic dysfunction, and recommended Thorson continue light-duty

restrictions with minimal overhead work and less frequent rotating

movement. He noted it was difficult for Thorson to work within her
 4

physical restrictions, apparently referring to the unavailability of light-

duty jobs at Larson’s plant. Thorson experienced modest improvement of

her condition at times from the physical therapy.

On November 25, 1996, after completing the therapy under

Dr. Toth’s care, Thorson was transferred from Larson’s sub-assembly

department to the door line. Although this transfer decreased the work-

related stress on her back and shoulders, Thorson continued to receive
treatment from Dr. Colby for thoracic and cervical spasm, bilateral

tendonitis, and lateral epicondylitis during the interval between

November 1996 and April 1998.

In May 1998, Thorson began receiving treatment from Dr. Clarence

Carlson, who ordered a functional capacity evaluation and recommended

a psychiatric consultation to rule out any underlying mental disorder.

The functional capacity evaluation performed on July 8 and 9, 1998

documented Thorson’s difficulty with overhead lifts and sustained

overhead work due to pain. The evaluator recommended frequent rest

breaks during sustained overhead activities and work-station

accommodations to avoid the need for floor-to-waist level lifting.

On July 13, 1998, Thorson underwent a psychiatric evaluation by
Dr. Karen Gosen. Dr. Gosen diagnosed major depression “with sleep,

appetite, energy, and mood changes,” and “chronic pain syndrome.” In

August 1998, Dr. Carlson informed Thorson he believed she had

fibromyalgia, and that she might benefit from chronic pain management.

The only documented medical treatment Thorson received between

August 1998 and May 1999 was for an injury to her right knee sustained

during the functional capacity evaluation in July 1998.3

3The knee injury was diagnosed as a meniscal tear and treated with surgery.

The commissioner found this injury compensable, and it is not at issue in this appeal.
 5

Thorson again consulted Dr. Colby for back spasms in May 1999.

On July 23, 1999, Thorson filed two petitions for workers’ compensation

benefits. The first petition alleged the July 1998 right leg injury. The

second petition alleged Thorson was disabled at “various times” from

1993 to 1999, and that she sustained a cumulative injury to her upper

back, neck, shoulders, and arms “on or about July 20, 1999.”4
Thorson returned to Dr. Carlson for treatment in January 2000.

She described the pain in her neck, upper thoracic spine, shoulders, and

arms as essentially unchanged, but reported increased symptoms in her

elbows. Dr. Carlson concluded Thorson was experiencing “low grade

bilateral epicondylitis,” which he characterized as “an acute/new

problem.” Dr. Carlson referred Thorson to Dr. Jeffrey Brault, who had

experience in the treatment of chronic musculoskeletal and chronic pain

disorders. Dr. Brault diagnosed “chronic myalgic pain syndrome” in

February 2000, prescribed an antidepressant, ordered physical therapy

for the shoulder and neck symptoms, and directed a continuation of

Thorson’s work restrictions.

Prior to the arbitration hearing on her petitions for workers’

compensation benefits, Thorson underwent a medical exam by Dr. Justin

Ban.5 Dr. Ban diagnosed multiple work-related injuries: a surgically

treated right medial meniscal tear, cumulative trauma disorder, chronic

cervicothoracic strain/sprain, and chronic pain disorder. His report

dated October 10, 2000 opined Thorson’s injuries caused a total whole-

person work related impairment of sixteen percent, consisting of five

4July 20, 1999 was the last day Thorson worked prior to filing the two petitions.

5Thisexamination was requested by Thorson pursuant to Iowa Code section
85.39 (1999) (authorizing claimants to obtain “a subsequent examination by a
physician of [their] own choice” at the employer’s expense after the employer has
obtained an evaluation of the claimant’s disability).
 6

percent for the cervicothoracic spine condition, one percent for the right

knee, and ten percent for the “chronic pain disorder associated with

psychological factors and cumulative trauma disorder.”6 As we have

already noted, Dr. Ban’s report (the only extant medical opinion

providing a permanent impairment rating of Thorson’s claimed

cumulative injury prior to the arbitration hearing) was excluded from

evidence by the deputy, but this court ordered the agency to consider

Dr. Ban’s opinion on remand.

Larson sought and obtained leave of the commissioner on remand

to develop and present medical evidence rebutting the opinions of

Dr. Ban. This evidence included a January 2005 report from Dr. Donna

Bahls, a board certified independent medical examiner. Dr. Bahls opined

Thorson experienced “chronic myofascial pain which is diffuse but

[incompatible with] the criteria for myofascial pain syndrome or

fibromyalgia.” Although Dr. Bahls believed work activities “could

temporarily aggravate or cause [the] underlying condition to be more

symptomatic,” she concluded work activities were not the cause of

Thorson’s condition. Dr. Bahls opined Thorson suffered no work-related

whole body impairment.

To rebut Dr. Ban’s finding of psychological impairment, Larson

also offered on remand a January 2005 medical report authored by

Dr. Charles Wadle, a psychiatrist. Dr. Wadle opined there was “no

6The hearing record did include other medical evidence supporting Thorson’s
cumulative injury claim. For example, Dr. Colby reported in October 2000 it was
probable that Thorson’s work activities at Larson were a substantial, but not
necessarily the exclusive, factor causing the various conditions he treated in Thorson’s
shoulder, upper extremities, and cervicothoracic spine. Dr. Colby further opined
Thorson’s “work activities did cause this condition more or less continuously during the
period 1992 to the present time . . . and will cause permanent impairment.” He did not,
however, express an opinion as to whether such impairment had yet manifested, or, if it
had, its extent.
 7

discernable psychiatric diagnosis for [Thorson] at this time,” and

therefore disputed Dr. Ban’s impairment rating.

As Dr. Ban’s October 2000 opinion was quite dated by the time of

the commissioner’s remand proceeding, Thorson also sought to present

new medical evidence for the agency’s consideration. She underwent an

examination by Dr. John Kuhnlein in March 2005. Dr. Kuhnlein

diagnosed chronic trapezius and scapulothoracic pain, and attributed a
three percent whole-body permanent impairment to it. He concluded

work activities were a substantial, but not necessarily the exclusive

cause of Thorson’s chronic pain and resulting impairment. Dr. Kuhnlein

also allocated one percent whole-body permanent impairment to the right

knee injury, but found no causal connection between Thorson’s work

activities and her shoulder, foot, and low-back complaints. Thorson

requested the commissioner to order Larson to pay for the Kuhnlein

examination under Iowa Code section 85.39.

In his remand decision, the commissioner found Thorson

sustained a work-related cumulative injury on April 26, 1996, the date

Thorson returned to Dr. Colby for treatment of her shoulder, back, and

elbow pain.7 The commissioner concluded Thorson’s claims were not
barred by the two-year statute of limitations because Thorson did not

know, nor should she have known, the conditions would have a

permanent adverse impact on her employment until she received

Dr. Ban’s report in 2000. The remand decision ordered Larson to pay

7Larson challenged this injury-date finding, claiming it had been deprived of
notice and opportunity to be heard as to an injury date other than July 20, 1999, the
cumulative injury date alleged in Thorson’s petition. The commissioner rejected
Larson’s due process claim, however, reasoning Larson was given sufficient notice of
potential alternative manifestation dates from Thorson’s pleading of a cumulative injury
date of “on or about July 20, 1999,” and from Thorson’s lengthy medical and
employment history disclosed in the course of the administrative proceeding.
 8

medical and transportation benefits, temporary partial benefits for the

periods of August 31, 1992 through September 22, 1992; October 2,

1992 through October 12, 1992; April 26, 1996 through January 2,

1997; and April 9, 1998 through December 21, 1998,8 and permanent
partial disability benefits compensating for an industrial disability of

twenty-five percent. In addition to the other relief granted, the remand

decision ordered Larson to reimburse Thorson pursuant to Iowa Code

section 85.39 for the full cost of Dr. Kuhnlein’s medical evaluation.

Thorson requested a rehearing. The commissioner subsequently

issued a rehearing decision awarding Thorson additional temporary total

disability benefits for an additional period from January 8, 2000 to

January 11, 2000, and providing Larson’s obligation to pay permanent

partial disability benefits should commence January 12, 2000. Larson

also filed a motion for rehearing prompting a second rehearing decision

which reduced the amount Larson was obligated to pay for

Dr. Kuhnlein’s examination.

On judicial review the district court affirmed the remand decision

in all respects.

II. Issues on Appeal.

Larson contends several errors require reversal of the

commissioner’s remand decision. Larson claims: (1) the finding of an

injury date prior to July 20, 1999, and the award of temporary partial

disability benefits are foreclosed by principles of issue preclusion, (2) its

rights to reasonable notice and an opportunity to be heard were violated

8As Thorson’s personnel records for 1992 were not in the record before the

agency, the commissioner ordered Larson to pay temporary partial disability benefits for
these periods, with the exact amount to be calculated by the parties. If the parties
could not agree as to the amount of such benefits, they were directed by the remand
decision to submit their calculations to the commissioner in furtherance of a
supplemental ruling.
 9

when the commissioner selected a cumulative injury date that is more

than three years prior to the injury date alleged in Thorson’s petition,

(3) Thorson’s cumulative injury claim is barred by the applicable statute

of limitations, (4) the award of temporary partial benefits and of

industrial disability benefits are not supported by substantial evidence,

(5) the commissioner erred in awarding medical benefits under section

85.27 for treatment rendered before the cumulative injury date, and (6)
the commissioner erred in ordering Larson to pay for more than one

examination of Thorson under section 85.39.

III. Scope of Review.

Iowa Code chapter 17A governs the scope of our review in workers’

compensation cases. Iowa Code § 86.26. It is well settled that “ ‘[t]he

interpretation of workers’ compensation statutes and related case law

has not been clearly vested by a provision of law in the discretion of the

agency.’ ” Lakeside Casino v. Blue, 743 N.W.2d 169, 173 (Iowa 2007)

(citation omitted). We therefore do not defer to the commissioner’s

interpretation of the law. Id.; see Iowa Code § 17A.19(10)(c).

Factual determinations in workers’ compensation cases, on the

other hand, are “ ‘clearly vested by a provision of law in the discretion of
the agency.’ ” Mycogen Seeds v. Sands, 686 N.W.2d 457, 465 (Iowa

2004) (citation omitted). Accordingly, we defer to the commissioner’s

factual determinations if they are based on “substantial evidence in the

record before the court when that record is viewed as a whole.” Iowa

Code § 17A.19 (10)(f). “Substantial evidence” is:

the quantity and quality of evidence that would be deemed
sufficient by a neutral, detached, and reasonable person, to
establish the fact at issue when the consequences resulting
from the establishment of that fact are understood to be
serious and of great importance.
 10

Iowa Code § 17A.19(10)(f)(1). Thus, when we review factual questions

delegated by the legislature to the commissioner, the question before us

is not whether the evidence supports different findings than those made

by the commissioner, but whether the evidence “supports the findings

actually made.” St. Luke’s Hosp. v. Gray, 604 N.W.2d 646, 649 (Iowa

2000) (citing Kiesecker v. Webster City Custom Meats, Inc., 528 N.W.2d

109, 110 (Iowa 1995)).
The application of the law to the facts is also an enterprise vested

in the commissioner. Mycogen Seeds, 686 N.W.2d at 465. Accordingly,

we reverse only if the commissioner’s application was “irrational, illogical,

or wholly unjustifiable.” Id.; Iowa Code § 17A.19(10)(l). This standard

requires us to allocate some deference to the commissioner’s

determinations, but less than we give to the agency’s findings of fact.

See Arthur E. Bonfield, Amendments to Iowa Administrative Procedure

Act, Report on Selected Provisions to Iowa State Bar Association and Iowa

State Government 70 (1998) (“[W]hen an agency is delegated discretion in

applying a provision of law to specified facts the scope of review

appropriately applied by courts must be deferential because the

legislature decided that the agency expertness justifies vesting primary
jurisdiction over that matter in the discretion of the agency rather than

in the courts.”).

We review constitutional claims de novo. Wright v. Iowa Dep’t of

Corr., 747 N.W.2d 213, 216 (Iowa 2008).

We review the commissioner’s determination on the statute of

limitations issue for correction of errors at law. Chapa v. John Deere

Ottumwa Works, 652 N.W.2d 187, 189 (Iowa 2002).
 11

IV. Discussion.

A. Issue Preclusion. Larson raises two issue preclusion claims

on appeal.9 First, Larson notes the commissioner’s appeal decision filed
on March 26, 2001 observed that “Defendants would not have been

reasonably put on notice by claimant’s discovery answer that [Thorson]

was actually alleging a date of injury in 1992 or 1996.” Larson contends

this language precluded a finding in the subsequent remand proceedings

that Larson had sufficient notice of the April 26, 1996 cumulative injury

date to satisfy the applicable due process standard. Second, Larson

asserts the commissioner was precluded on remand from finding

Thorson was entitled to temporary partial disability benefits because the

agency’s appeal decision had previously found Thorson failed to

demonstrate eligibility for TPD benefits.

We follow a well-established analytical framework in deciding

whether a party is precluded from re-litigating an issue. The

prerequisites for preclusion are:

(1) the issue concluded must be identical; (2) the issue must
have been raised and litigated in the prior action; (3) the
issue must have been material and relevant to the
disposition of the prior action; and (4) the determination
made of the issue in the prior action must have been
necessary and essential to the resulting judgment.

Hunter v. Des Moines, 300 N.W.2d 121, 123 (Iowa 1981) (citation

omitted). Larson’s preclusion claims must fail because the subject

issues were not decided in a “prior action.” The commissioner’s appeal

decision and the remand decision are parts of a single action, not

adjudications of consecutive actions in which the doctrine of issue

9Thorson contends Larson failed to argue preclusion before the commissioner on
remand, and consequently failed to preserve the issue for our review. We nonetheless
elect to decide them.
 12

preclusion might have application. Cf. State v. Pexa, 574 N.W.2d 344,

347 (Iowa 1998) (holding the district court’s original decision, a decision

on appeal, and the district court’s decision on remand is a “continuous

judicial examination . . . in the same proceeding” for the purpose of

evaluating whether jeopardy attaches to a criminal defendant).

B. Notice of Date of Injury. Larson next contends its right to

due process was violated when the commissioner found a date of injury
more than three years prior to the date alleged in Thorson’s petition. A

proper understanding of this issue is informed by a review of this court’s

decisions addressing the compensability of cumulative work-related

injuries.

We adopted the cumulative injury rule in McKeever Custom

Cabinets v. Smith, 379 N.W.2d 368 (Iowa 1985). By their very nature,

cumulative injuries develop over time and eventually result in a

compensable disability. McKeever, 379 N.W.2d at 373. Because such

injuries develop gradually as a consequence of repetitive motion or

overuse, the enterprise of determining the date when a cumulative injury

“occurs” is typically a challenging task. Although it can be difficult to

identify with precision, the date of cumulative injury is of critical
importance in the determination of which of multiple employers and

insurance carriers are “on the risk, whether notice of injury and claim

were within the statutory period, whether statutory amendments were in

effect, which wage basis applies, and many others.” Oscar Mayer v.

Tasler, 483 N.W.2d 824, 829 (Iowa 1992). In McKeever, we held a

cumulative injury “occurs” for limitation purposes when, “because of

pain or physical inability, [the employee] can no longer work.” 379

N.W.2d at 374.
 13

We revisited the analytical framework for identifying a claimant’s

date of cumulative injury in Tasler. 483 N.W.2d at 829. Tasler, who

performed various jobs requiring repetitive motion in Oscar Mayer’s

packing plant, was repeatedly treated for neck, upper extremity, and

back pain during the more than five years of her employment. Id. at 827.

Despite her history of recurring medical treatment and multiple transfers

to lighter-duty work stations during those years, Tasler apparently did
not lose any time from work before the plant closed permanently on

February 3, 1989. Id. at 828. Tasler subsequently filed five petitions

seeking workers’ compensation benefits for work-related injuries on four

separate injury dates. Id. at 825–27. The agency found Tasler failed to

prove she suffered a compensable injury on any one of the four dates

alleged in her petitions, but nonetheless found she had sustained a

“cumulative, repetitive, overuse type of injury” which caused an

industrial disability of fifteen percent on the date the plant closed. Id. at

828. The employer sought judicial review of the agency’s date-of-injury

finding, contending the plant closing date could not have been the date of

injury because Tasler’s medical condition had not prevented her from

working on or before that date. Id. The employer further asserted its
right to due process was violated when the agency found an injury date

that had not even been alleged by Tasler. Id.

In upholding the commissioner’s finding of Tasler’s injury date, we

relied upon the “manifestation” rule, which defines the date of injury as

the date on which a “disability manifests itself.” Id. at 829 (citing 1B

Arthur Larson, Workers’ Compensation Law § 39.50 (1991)). We

concluded an injury is manifest on “ ‘the date on which both the fact of

the injury and the causal relationship of the injury to the claimant’s

employment would have become plainly apparent to a reasonable
 14

person.’ ” Id. (quoting Bellwood Nursing Home v. Indus. Comm’n, 505

N.E.2d 1026, 1029 (Ill. 1987)). The commissioner’s determination of the

injury date “is entitled to a substantial amount of latitude” as it is an

“inherently fact-based determination” derived from a multitude of factors.

Id. We found substantial evidence supporting the selection of the plant

closing date as Tasler’s date of injury. Id. at 830.

We rejected Oscar Mayer’s due process challenge to the
commissioner’s selection of an injury date that had not been alleged by

Tasler. In disposing of the due process argument, we stated:

due process requires that a party “be informed somehow of
the issue involved in order to prevent surprise at the hearing
and allow an opportunity to prepare. . . . The test is
fundamental fairness, not whether the notice meets
technical rules of common law pleading.”

Id. at 828 (quoting Wedergren v. Bd. of Dirs., 307 N.W.2d 12, 16 (Iowa

1981)). We concluded Oscar Mayer was sufficiently alerted to the

cumulative nature of Tasler’s claim because one of the five petitions

attributed the claimed disability to a “gradual injury from skinning

hams,” while another alleged an injury arising from “repetitive use and

strain of [the claimant’s] back during [the] course of employment.” Id.

Under the circumstances, we concluded Oscar Mayer had failed to

demonstrate prejudice. Id.

We again confronted an employer’s claim of inadequate notice of an

alleged cumulative injury in University of Iowa Hospitals & Clinics v.

Waters, 674 N.W.2d 92 (Iowa 2004). Waters, who had been employed as

a hospital custodian for nearly thirty years, filed two petitions for

arbitration. Waters, 674 N.W.2d at 93. The first alleged he sustained a

back injury on October 24, 1996 while pushing a loaded cart. Id. at 93–

94. The second claimed another back injury occurred on June 16, 1997
 15

as Waters was “lifting, carrying, and dumping heavy trash at work.” Id.

at 94. When uncertainty arose during Waters’ deposition as to the date

of injury, counsel disclosed his intention to amend the petition to allege

the injury occurred on June 21, 1997, the last date Waters worked for

the employer. Id. The commissioner found Waters sustained a

cumulative back injury on his last day of work, and awarded permanent

total disability benefits. Id. at 94–95. The district court reversed the
agency’s decision, concluding the employer was prejudiced by Waters’

change of theory from claims of two separate traumatic injuries to a

claim of cumulative injury on a date not alleged in the petitions. Id. at

95.

In Waters, we noted “ ‘[a]n application for arbitration is not a

formal pleading and is not to be judged by the technical rules of

pleading.’ ” Id. at 96–97 (emphasis omitted) (quoting Coghlan v. Quinn

Wire & Iron Works, 164 N.W.2d 848, 850 (Iowa 1969)). In further

elucidating this principle, we stated:

“The petition for arbitration may state the claims in general
terms and technical or formal rules of procedure need not be
observed. The key to pleading in an administrative process
is nothing more than opportunity to prepare and defend.
The employer is to be afforded a substantive right to be at
least generally informed as to the basic material facts upon
which the employee relies as a basis for compensation.”

Id. at 97 (quoting James R. Lawyer and Judith Ann Graves Higgs, Iowa

Workers’ Compensation–Law & Practice § 21-7, at 231 (3d ed. 1999)

(footnotes and internal quotations omitted)). We found this standard of

notice was met by Waters’ “vague use of three gerunds (“lifting, carrying,

and dumping”) [which] implie[d] his injury resulted from repetitive work-

related behavior.” Id. at 98. In determining the adequacy of the notice of

Waters’ claimed date of injury, we noted discovery should have informed
 16

the employer of the cumulative nature of the injury, particularly in light

of testimony asserting Waters requested a change of his work

responsibilities in order to avoid the exertional activities thought to be

exacerbating his low-back symptoms. Id. “Although a history of back

problems does not always necessitate a cumulative injury finding . . . ,

such a history should alert an employer to the possibility of a cumulative

injury claim.” Id.
With the principles established in McKeever, Tasler and Waters in

mind, we now consider whether Larson’s right to due process was

infringed by the agency’s finding that Thorson suffered a cumulative

injury on April 26, 1996. We first note Thorson’s petition undercuts

Larson’s argument that it was unaware of the possibility of an injury

prior to July 20, 1999. Thorson expressly alleged her injury occurred

“cumulatively, gradually, and progressively,” and caused her to be

disabled at “various times [from] 1993–1999.” Larson had a due process

right to be “sufficiently apprised of the possibility that the cumulative

injury doctrine might be relied upon.” Tasler, 483 N.W.2d at 828

(emphasis added). Thorson’s petition provided ample notice by expressly

apprising Larson of a claim that Thorson’s injury arose cumulatively and
produced disability at times before 1999. Furthermore, Larson had

actual notice of the long progression of Thorson’s developing chronic pain

symptoms as a consequence of: (1) the enduring employer-employee

relationship during which Thorson was assigned to light duty because of

her ongoing physical symptoms; (2) Thorson’s petition alleging disability

at various times from 1993 to 1999; and, (3) the employer’s access to

Thorson’s medical records generated in the course of treatment of those

symptoms long before July 20, 1999. On this record, we find no merit in

Larson’s due process challenge.
 17

C. Statute of Limitations. As Thorson had not been paid

disability benefits for the claimed cumulative injury before the petition

was filed, the pertinent statute of limitations for her claim is “two years

from the date of the occurrence of the injury for which benefits are

claimed. . . .” Iowa Code § 85.26(1). Consistent with this court’s prior

decisions, Thorson is entitled to the benefit of the discovery rule, Herrera

v. IBP, Inc., 633 N.W.2d 284, 287 (Iowa 2001), and the statute of
limitations did not begin to run until she recognized, or should have

recognized, the “ ‘nature, seriousness and probable compensable

character’ ” of the disability. Orr v. Lewis Cent. Sch. Dist., 298 N.W.2d

256, 257 (Iowa 1980) (citation omitted); accord Herrera, 633 N.W.2d at

287. Thorson’s knowledge of these three triggering factors may be actual

or imputed from the record. Ranney v. Parawax Co., 582 N.W.2d 152,

154–55 (Iowa 1998).

The commissioner found Thorson’s cumulative injury became

manifest on April 26, 1996 because by that date she knew she had a

chronic pain condition that was causally connected to her work

activities. Larson contends the petition filed on July 23, 1999 was

therefore untimely because it was filed more than two years after the
injury date. We disagree. The statute of limitations does not necessarily

begin to run on the date the injury becomes manifest. Herrera, 633

N.W.2d at 288. In Herrera, we noted the discovery rule may cause the

date of a cumulative injury’s manifestation to diverge from the date when

the limitation period begins to run:

[A] cumulative injury is manifested when the claimant, as a
reasonable person, would plainly be aware (1) that he or she
suffers from a condition or injury, and (2) that this condition
or injury was caused by the claimant’s employment. Upon
the occurrence of these two circumstances, the injury is
deemed to have occurred. Nonetheless, by virtue of the
 18
discovery rule, the statute of limitations will not begin to run
until the employee knows that the physical condition is
serious enough to have a permanent adverse impact on the
claimant’s employment or employability, i.e., the claimant
knows or should know the ‘nature, seriousness, and
probable compensable character’ of his injury or condition.

Id. (citing Orr, 298 N.W.2d at 257).

Larson contends the court modified the Herrera formulation of the

discovery rule in Chapa, 652 N.W.2d at 189. In Chapa, we restated the

rule announced in Herrera that the statute of limitations in a cumulative
injury case “does not begin to run until the worker recognizes, or should

recognize, the ‘nature, seriousness and probable compensable character’

of the disability.” 652 N.W.2d at 189 (quoting Orr, 298 N.W.2d at 257).

We failed, however, in Chapa to quote language from Herrera which

clearly communicated that a claimant is deemed to know the nature,

seriousness and probable compensable character of an injury when she

knows her physical condition is serious enough to have a permanent

adverse impact on her employment or employability. See Herrera, 633

N.W.2d at 288.

Larson asserts our omission in Chapa of the “permanent adverse

impact” language from Herrera is tantamount to a repudiation of the
proposition that the limitations period does not begin to run until the

claimant has knowledge of an injury’s permanent impact on her

employment. Our failure to repeat verbatim language from Herrera in

Chapa should not be so understood. Indeed, we cited Herrera in Chapa,

and gave no indication of a retreat from the earlier formulation of the

discovery rule as it is applied in cumulative injury and other workers’

compensation cases. Chapa, 652 N.W.2d at 189–90. We now clarify that

our “shorthand” expression of the discovery rule in Chapa did not signal

the court’s intent to reformulate the rule.
 19

In his remand proceeding, the commissioner found Thorson was

not aware of the nature, seriousness and probable compensable

character of her injury before she filed her petitions on July 28, 1999.

Larson challenges this finding, emphasizing Thorson experienced, and

sought medical treatment for, pain in her neck, upper extremities, and

back long before that date. Although the record could support a finding

of an earlier discovery date, the finding made by the commissioner is
supported by substantial evidence in the record. Although Thorson

claimed she was unable to take advantage of some overtime hours

because of her chronic pain condition, she had not lost any regular

hours of work and she was still working full-time with some overtime

hours when she filed her petitions on July 28, 1999. Although light duty

had been ordered by a medical provider, Thorson had been given neither

permanent work restrictions nor a permanent physical impairment rating

before that date. Thus, we affirm the agency’s determination that

Thorson’s claims were timely under the discovery rule.

D. Industrial Disability. On the subject of Thorson’s claimed

industrial loss, the commissioner’s remand decision stated:

The claimant is still employed at her old job. She has not
suffered a loss of earnings as a result of work injury, other
than lost overtime. She continues to suffer with pain in her
neck and shoulder blades, muscle spasms in her shoulders,
and pain in both elbows, especially when lifting, pulling,
grasping, doing overhead work, reaching out, pushing or
grasping, or pulling. She has no permanent work
restrictions, however. She has a rating of permanent partial
impairment of five percent of the body as a whole from her
chronic pain syndrome from Dr. Ban, and three percent of
the body as a whole from Dr. Kuhnlein. Dr. Carlson rated
her impairment as zero percent, as did Dr. Bahls.

As a result of the work injury, there are many personal
activities she can no longer perform. She was 44 years old
at the time of the hearing; she is 48 now. Her work
 20
experience is limited to manual labor, virtually all for one
employer. She has only a high school diploma.

Her ratings of impairment are low; she has no
restrictions; she is still working at her old job and has not
lost earnings other than lost overtime. Based on these and all
appropriate factors of industrial disability, it is found that as
a result of her work injury of April 26, 1996, the claimant
has an industrial disability of 25 percent.

(Emphasis added.) Larson challenges the sufficiency of the evidence

supporting the commissioner’s findings that Thorson (1) lost overtime

wages as a consequence of her injury, and (2) sustained a twenty-five

percent industrial disability.

1. Lost overtime wages. Thorson testified that although voluntary

overtime work was available to Larson’s employees, she did not take it (or

took less than was available to her) on occasion during the year before

the arbitration hearing because of her work restrictions, or because she

felt unable to work the additional hours. We conclude this testimony

was minimally sufficient to constitute substantial evidence supporting

the commissioner’s finding that Thorson lost some overtime earnings as

a consequence of the cumulative injury.

Although we have concluded the quantum of proof supporting the

finding of a loss of overtime earnings is minimally sufficient to sustain it,

our conclusion that no reversible error resulted from the commissioner’s

consideration of that loss as a factor in the determination of industrial

disability rests upon an additional ground. On judicial review we may

grant relief to a party based on a finding of fact not supported by

substantial evidence only when the agency’s action was “based upon”

that determination of fact. Iowa Code § 17A.19(10) (“The court shall

reverse, modify, or grant other appropriate relief from agency action . . . if

it determines that substantial rights of the person seeking judicial relief

have been prejudiced because the agency action is . . . . (f) Based upon a
 21

determination of fact . . . that is not supported by substantial evidence in

the record when that record is viewed as a whole.”).

We conclude Larson has failed to demonstrate the commissioner’s

determination of Thorson’s industrial disability was based upon the

finding that Thorson sustained claimed loss of overtime earnings. When

viewed in the full context of the remand decision, we believe the

commissioner’s passing references to Thorson’s claim of “lost overtime”
were calculated primarily to acknowledge the cumulative injury did not

cause a significant loss of earnings, a fact that tends to mitigate rather

than increase industrial disability. Industrial disability is, of course, a

measure of one’s loss of earning capacity in the competitive labor market.

Acuity Ins. v. Foreman, 684 N.W.2d 212, 220 (Iowa 2004); Excel Corp. v.

Smithart, 654 N.W.2d 891, 901 (Iowa 2002). Proof of an actual reduction

in the claimant’s earnings is not essential to establish a loss of earning

capacity. St. Luke’s Hosp., 604 N.W.2d at 653. As Larson has not

shown the commissioner’s finding of a twenty-five percent industrial

disability was substantially “based on” Thorson’s claimed loss of an

undetermined amount of overtime earnings, we conclude Larson’s

substantial rights were not prejudiced by the references to such evidence
in the remand decision.

2. Industrial disability rating. We now turn to Larson’s claim that

the commissioner erred in awarding Thorson benefits for a twenty-five

percent industrial disability. This issue is a mixed question of law and

fact, as the determination of industrial disability required the

commissioner to apply established law (the factors considered in

determining whether an industrial disability occurred) to the facts. As

Larson’s challenge to the agency’s industrial disability determination is a

challenge to the agency’s application of law to the facts, we review this
 22

issue under the “irrational, illogical, or wholly unjustifiable” standard.

Meyer v. IBP, Inc., 710 N.W.2d 213, 218–19 (Iowa 2006).

Larson contends the commissioner’s finding that Thorson suffered

a twenty-five percent loss of earning capacity as a result of the injury was

irrational, illogical, or wholly unjustifiable because “she has no

restrictions, is working overtime, is working a second job, and earning

more now than she ever earned.” While the evidence highlighted by
Larson was certainly relevant to the commissioner’s determination of

industrial disability, and was in fact considered by the commissioner, it

is not dispositive of the issue. An assessment of industrial disability

implicates “ ‘all the factors that bear on [the claimant’s] actual

employability.’ ” Thilges v. Snap-On Tools Corp., 528 N.W.2d 614, 616

(Iowa 1995) (quoting Guyton v. Irving Jensen Co., 373 N.W.2d 101, 104

(Iowa 1985)) (emphasis added). These factors include the claimant’s

“age, education, qualification, experience, and inability due to injury to

engage in the employment for which the claimant is fitted.” Id. (citing

Doerfer Div. of CCA v. Nicol, 359 N.W.2d 428, 438 (Iowa 1984)). And as

we have already noted, the fact that Thorson “was able to continue at

h[er] job does not prove, as a matter of law, that [s]he has suffered no
loss of earning capacity.” Second Injury Fund v. Hodgins, 461 N.W.2d

454, 456 (Iowa 1990).

In arriving at the industrial disability determination of twenty-five

percent, the commissioner considered Thorson’s modest functional

impairment, as assessed by Dr. Ban and Dr. Kuhnlein, as well as the

other relevant factors including Thorson’s age, educational background,

qualifications for employment, work experience, motivation, loss of

earnings, severity and situs of the injury, and history of work (light duty)

restrictions. Although factors emphasized by Larson (absence of
 23

permanent work restrictions, continued full-time work including some

overtime, and a history of increased actual earnings after the date of

cumulative injury) certainly mitigated the extent of industrial disability in

this case, other substantial evidence in the record supported the

determination made by the agency in this case. Thorson’s age, her work

experience limited to manual labor, her educational background, and the

nature of her chronic pain condition are factors supporting the agency’s
industrial disability determination. In short, we cannot say the

commissioner’s resolution of this issue on remand was irrational,

illogical, or wholly unjustifiable, and we affirm on this issue.

E. Temporary Partial Disability Benefits. When it is

“medically indicated that an employee is not capable of returning to

employment substantially similar to the employment in which the

employee was engaged at the time of injury, but is able to perform other

work consistent with the employee’s disability,” a claim for temporary

partial disability benefits may be made. Iowa Code § 85.33(2). Such

benefits are intended to compensate an injured employee for a

“temporary partial reduction in earning ability as a result of the

employee’s temporary partial disability.” Id. The amount of temporary
partial disability benefits owed by the employer is equal to “sixty-six and

two-thirds percent of the difference between the employee’s weekly

earnings at the time of injury, computed in compliance with section

85.36, and the employee’s actual gross weekly income from employment

during the period of temporary partial disability.” Id. § 85.33(4).

Larson raises two challenges to the agency’s award of temporary

partial disability benefits in this case. First, Larson contends the law

does not authorize an award of such benefits for periods before Thorson’s

cumulative injury became manifest on April 26, 1996. Second, Larson
 24

claims in the alternative that even if the law does authorize an award of

permanent partial disability benefits to compensate a claimant for a

diminution of earnings sustained prior to the manifestation date, the

commissioner erred in awarding such benefits in this case because

Thorson failed as a matter of law to meet her burden to prove the

cumulative injury caused a decrease in her earnings sufficient to sustain

the award. We address these arguments in turn.
1. TPD benefits prior to date of manifestation. Iowa Code section

85.33 provides, in relevant part:

2. “Temporary partial disability” or “temporarily, partially
disabled” means the condition of an employee for
whom it is medically indicated that the employee is not
capable of returning to employment substantially
similar to the employment in which the employee was
engaged at the time of injury, but is able to perform
other work consistent with the employee’s disability.
“Temporary partial benefits” means benefits payable,
in lieu of temporary total disability and healing period
benefits, to an employee because of the employee’s
temporary partial reduction in earning ability as a
result of the employee’s temporary partial disability.
Temporary partial benefits shall not be considered
benefits payable to an employee, upon termination of
temporary partial or temporary total disability, the
healing period, or permanent partial disability,
because the employee is not able to secure work
paying weekly earnings equal to the employee’s weekly
earnings at the time of injury.

3. If an employee is temporarily, partially disabled and
the employer for whom the employee was working at
the time of injury offers to the employee suitable work
consistent with the employee’s disability the employee
shall accept the suitable work, and be compensated
with temporary partial benefits. If the employee refuses
to accept the suitable work with the same employer,
the employee shall not be compensated with temporary
partial, temporary total, or healing period benefits
during the period of the refusal. If suitable work is not
offered by the employer for whom the employee was
working at the time of the injury and the employee
who is temporarily partially disabled elects to perform
 25
work with a different employer, the employee shall be
compensated with temporary partial benefits.
Iowa Code § 85.33(2)–(3).

Iowa Code section 85.32 provides that “except for injuries resulting

in permanent partial disability, compensation shall begin on the fourth

day of disability after the injury.” (Emphasis added.)10 Larson contends
the agency erred in its remand decision by awarding temporary partial

disability benefits for periods prior to April 26, 1996, and extending as

far back as 1992. As this argument challenges the agency’s

interpretation of a provision of law, a function not clearly vested in the

agency, Mycogen Seeds, 686 N.W.2d at 464, we are not constrained by

deference to the agency’s decision on this issue. Iowa Code

§ 17A.19(10)(c).

When called upon to interpret a statute, we first determine

whether the legislative enactment is ambiguous. If it is clear and

unambiguous, “we give [the] statute a plain and rational meaning.” In re

T.S., 705 N.W.2d 498, 502 (Iowa 2005) (citing ABC Disposal Sys., Inc. v.

Dep’t of Natural Res., 681 N.W.2d 596, 603 (Iowa 2004)). If, on the other

hand, the statute is ambiguous, we rely on well-established rules to aid
our interpretation. Waukee v. City Dev. Bd., 590 N.W.2d 712, 717 (Iowa

1999). A statute or rule “is ambiguous if reasonable minds could differ

or be uncertain as to the meaning of the statute.” Carolan v. Hill, 553

N.W.2d 882, 887 (Iowa 1996).

“Ambiguity may arise in two ways: (1) from the meaning of

particular words; or (2) from the general scope and meaning of a statute

when all its provisions are examined.” Id. (citation omitted). We

conclude the phrase “after the injury” in section 85.32 is ambiguous

10Ifthe period of incapacity extends beyond the fourteenth day following the date
of injury, the claimant’s compensation for the third week of disability includes an
additional amount equal to three days of compensation. See Iowa Code § 85.32.
 26

when applied to cumulative injuries which develop gradually and

progressively rather than suddenly, traumatically, or discretely.
Reasonable minds could differ or be uncertain as to whether the phrase

“after the injury” in a cumulative injury case means a temporary partial

disability can be compensable only if it arises after the manifestation

date, or whether it can be compensable even if it arises before the

manifestation date as a consequence of a cumulative injury process

which subsequently progresses to the point of manifestation.

The ambiguity within the statute is made apparent in the

arguments advanced in this case by Larson and Thorson. Larson

contends it can have no liability to Thorson for workers’ compensation

benefits until after April 26, 1996, the manifestation date found by the

commissioner. Thorson advances a much different interpretation of the

phrase “after the injury” in section 85.32. She notes cumulative injuries

develop gradually and progressively, and employees who suffer them will

have periods of temporary, but progressively more profound, restriction

or dysfunction until the injury becomes so disruptive as to satisfy the

manifestation standard. As the deterioration of their functioning

advances toward manifestation, employees who experience cumulative

trauma may require medical treatment, modifications of their work

activities, and adjustments of their work schedules in order to continue

their employment. Such employees may continue to work, as Thorson

did, but experience temporary reductions of their earnings and require

medical treatment long before their cumulative injuries are “manifest”

under the standard established in our prior decisions. Furthermore,

Thorson posits the legislature’s use of the phrase “after the injury” rather

than “after the date of injury” or “after the date of manifestation of the

injury” leaves room for the likelihood that the drafters intended to
 27

provide a remedy for temporary partial disability, if any, that occurs prior

to the date of manifestation.

We interpret the phrase “after the injury” in section 85.32 to

permit an award of temporary partial disability benefits upon proof of a

diminution of a claimant’s earnings during periods of temporary

incapacity caused by a work-related condition which later manifests as a

cumulative injury. Our resolution of this issue is faithful to the well-
established rule that chapter 85 is liberally construed in favor of the

employee, with any doubt in its construction being resolved in the

employee’s favor. Teel v. McCord, 394 N.W.2d 405, 406–07 (Iowa 1986).

Invocation of this rule is appropriate under the circumstances presented

here because we do not believe the General Assembly intended to deny a

remedy under chapter 85 to employees who suffer a temporary reduction

of earnings before a work-related cumulative injury progresses to the

point of “manifestation” as we have defined it in our cases. We therefore

affirm the commissioner’s interpretation of section 85.32 as authorizing

an award of temporary partial disability benefits for periods prior to the

date of manifestation upon proof that a claimant’s earnings were

diminished temporarily as a result of a work-related cumulative injury
process.

2. Thorson’s proof of the TPD claim. Having concluded an award

for temporary partial disability benefits may, upon proper proof, be

established for periods prior to the date of a cumulative injury’s

manifestation, we next address whether the record in this case contains

substantial evidence supporting the commissioner’s award in this case.

Larson contends the award is not supported in the record because,

although Thorson testified she lost an unquantified amount of overtime

wages in the year before the arbitration hearing held on November 21,
 28

2000, she supplied no proof that the diminution of earnings claimed for

the earlier relevant periods (prior to November 21, 1999) were caused by

the work-related cumulative injury.11 Noting that some of Thorson’s

claimed periods of temporary partial disability included holidays or

vacations, Larson contends substantial evidence in the record does not

support a finding that any diminution of overtime earnings was caused

by the claimed cumulative injury.

Thorson contends her proof of a causal connection between the

claimed diminution of her earnings (a loss of overtime hours and related

pay) and the cumulative injury is adequate in this case. First, she

emphasizes that she worked under a medical restriction for light duty

during the weeks for which she seeks temporary partial disability

benefits. Second, Thorson relies on the medical records evidencing her

long history of chronic pain symptoms, and her testimony establishing

that she “turned down voluntary overtime” during the year prior to the

arbitration hearing when she “didn’t think [she] could work past 3:30.”

In the alternative, Thorson points out section 85.33 does not

expressly require proof of a causal connection between her cumulative

injury and the diminution of her earnings, and she asserts an award of

temporary partial disability benefits may be supported by mere proof of a

diminution of her earnings during weeks she worked under a light-duty

restriction from her treating physician. In furtherance of her position on

this point, Thorson notes section 85.33 provides a formula for calculating

permanent partial disability benefits, but gives no indication that proof of

a causal connection between a work-related cumulative injury and a

reduction in earnings is required.

11Only one of the periods for which Thorson was awarded temporary partial
disability benefits (January 8, 2000 to January 11, 2000) was within the year before the
arbitration hearing.
 29

Although we reject Thorson’s contention that she had no burden to

produce evidence of a causal connection between the cumulative injury

and the claimed diminution of earnings during the relevant weeks to

support an award of temporary partial disability benefits under section

85.33, we conclude she did produce substantial evidence of a causal

connection in this case. Thorson worked under a physician-imposed

light-duty restriction during the relevant weeks, and the medical records
clearly evidence she was suffering from chronic pain in multiple parts of

her body throughout that time. This evidence is minimally sufficient to

support a causal nexus between Thorson’s cumulative injury and the

claimed diminution of her earnings for the relevant weeks. Although

Larson contends on appeal that Thorson might have worked less during

some of those weeks not because of an injury, but because holidays,

funerals, or vacations reduced her availability for work, the weight to be

given such evidence was a matter for the commissioner to decide. We

therefore affirm on this issue.

F. Medical Benefits Prior to Date of Manifestation. Similar

to its challenge to the agency’s award of TPD benefits prior to the date of

manifestation, Larson challenges the deputy commissioner’s award of
medical benefits prior to the date of manifestation. The medical benefits

statute, Iowa Code section 85.27(1), requires the employer to pay medical

and transportation expenses “for all injuries compensable under this

chapter.” Interpretation of section 85.27(1) has not clearly been vested

in the discretion of the workers’ compensation commissioner, and we

therefore owe no deference to the agency’s interpretation. Iowa Code

§ 17A.19(10)(c).

The plain language of section 85.27(1) requires the employer to pay

for all medical costs incurred as a result of an injury compensable under
 30

chapter 85. Section 85.27(1) does not expressly limit the employer’s

liability for medical costs to costs incurred following manifestation of a

compensable workers’ compensation claim. The only statutory

requirement for compensability is that the treatment be “for” an injury

compensable under the chapter. Work-related cumulative injuries are, of

course, compensable under chapter 85, and consequently section

85.27(1) requires the employer to compensate the employee for
reasonable medical costs incurred as a result of such injuries.

We find no language in the statute suggesting that an employer is

without obligation to provide reasonable medical treatment for work-

related health problems in advance of the date of manifestation of a

cumulative injury. We conclude the agency did not err in construing

section 85.27(1) to require Larson to pay for medical treatment for

Thorson’s work-related condition that later manifested as a cumulative

injury.

G. Reimbursement for Multiple IMEs. Iowa Code section

85.39 provides, in relevant part, as follows:

If an evaluation of permanent disability has been made by a
physician retained by the employer and the employee
believes this evaluation to be too low, the employee shall,
upon application to the commissioner and upon delivery of a
copy of the application to the employer and its insurance
carrier, be reimbursed by the employer the reasonable fee for
a subsequent examination by a physician of the employee’s
own choice, and reasonable necessary transportation
expenses incurred for the examination.
Iowa Code § 85.39 (emphasis added). Larson was ordered to pay for

Dr. Ban’s October 2000 examination under this statute. Having paid for

the prior examination, Larson contends the plain language of section

85.39 precludes its liability for the subsequent examination by

Dr. Kuhnlein. We agree, and therefore reverse that part of the
 31

commissioner’s remand decision ordering Larson to pay for the Kuhnlein

examination.12
V. Conclusion.

We affirm all aspects of the commissioner’s remand decision except

for the order directing Larson to pay the cost of the Kuhnlein

examination pursuant to section 85.39.

AFFIRMED IN PART AND REVERSED IN PART.

All justices concur except Wiggins and Baker, JJ., who take no

part.

12We acknowledge the unusual circumstances which Thorson faced on remand
in this case. Dr. Ban, who had provided Thorson’s only permanent impairment rating
prior to the November 2000 arbitration hearing, was not available to update his report.
Although Larson presented two new medical opinions for the commissioner’s
consideration in the course of the remand proceeding, and Thorson had a strong
interest in responding to this new evidence, the plain language of section 85.39 does
not authorize the commissioner to require Larson to pay for a second examination in
this case. Cf. State v. Kidd, 562 N.W.2d 764, 765 (Iowa 1997) (stating the word “an” as
used in a criminal statute prohibiting unauthorized possession of “an offensive weapon”
denotes a singular unit of prosecution). It is the legislature’s role to determine if
claimants should be entitled to more than one examination at the employer’s expense
under the statute.