Notice: This opinion is subject to formal revision before publication in the
Atlantic and Maryland Reporters. Users are requested to notify the Clerk of the
Court of any formal errors so that corrections may be made before the bound
volumes go to press.

              DISTRICT OF COLUMBIA COURT OF APPEALS

                                    No. 17-AA-832

                    HOWARD UNIVERSITY HOSPITAL, PETITIONER,

                                           v.

 DISTRICT OF COLUMBIA DEPARTMENT OF EMPLOYMENT SERVICES, RESPONDENT,

                                           and

                          JAMES M. LYLES, JR., INTERVENOR.

                      On Petition for Review of an Order of the
             District of Columbia Department of Employment Services
                            Compensation Review Board
                                    (CRB-36-17)

(Argued September 25, 2018                                  Decided January 31, 2019)

      William H. Schladt for petitioner.

       Karl A. Racine, Attorney General for the District of Columbia, Todd S. Kim,
Solicitor General at the time the statement was filed, and Loren L. AliKhan, Deputy
Solicitor General at the time the statement was filed, filed a statement in lieu of brief.

       David J. Kapson, with whom Kevin H. Stillman was on the brief, for
intervenor.

      Before THOMPSON and MCLEESE, Associate Judges, and PRYOR, Senior
Judge.
                                          2

      MCLEESE, Associate Judge: Petitioner Howard University Hospital (HUH)

challenges an award of workers’ compensation to intervenor James M. Lyles, Jr. We

vacate and remand for further proceedings.



                                          I.



      Mr. Lyles worked for HUH as a radiological technician. In 2013, he felt pain

in his right shoulder while lifting a patient to prepare for an x-ray. Mr. Lyles

received medical treatment and eventually filed a workers’ compensation claim

seeking disability benefits pursuant to D.C. Code § 32-1508 (3)(A) and (S) (2012

Repl.), which provide for compensation for permanent partial loss of the use of an

arm. HUH did not dispute that Mr. Lyles had suffered a work-related injury and was

entitled to some compensation. HUH and Mr. Lyles presented conflicting evidence

about the extent of Mr. Lyles’s disability.



      At a February 2017 hearing before an administrative law judge (ALJ), Mr.

Lyles testified that he still felt a burning and tearing sensation from his neck down

into his arm, which was aggravated by motions such as lifting, pulling, and pushing.

He further testified that his right arm was very weak and that he therefore did not

use his right arm as much as he used to. At the time of the hearing, Mr. Lyles was
                                         3

working for a new employer as a radiological technician/medical assistant. His

duties for his new employer did not include pulling or lifting of patients or

machinery. Mr. Lyles also testified that he was no longer able to bowl or lift heavy

weights at the gym. Mr. Lyles acknowledged that he had suffered a previous injury

to his right shoulder in 2011, while working for a different employer, and had

claimed disability benefits from his employer in connection with that injury. That

disability claim was settled.



      Mr. Lyles introduced the results of an independent medical examination

conducted in 2016 by Dr. Matthew Menet. Dr. Menet concluded that Mr. Lyles still

had difficulty lifting, reaching, and pulling. In opining about the extent of Mr.

Lyles’s disability, Dr. Menet relied upon the Fourth Edition of the American Medical

Association Guides to the Evaluation of Permanent Impairment (AMA Guides). Dr.

Menet also considered pain, loss of function, weakness, and loss of endurance. Dr.

Menet concluded that Mr. Lyles had a 47% permanent impairment to his right upper

extremity. That figure rested on adding the following specific impairments: 3%

based on lack of full range of motion, 12% for pain, 10% for weakness, 12% for loss

of function, and 10% for loss of endurance. According to Dr. Menet, 20% of the

47% impairment was related to Mr. Lyles’s 2011 injury and 27% was related to Mr.

Lyles’s 2013 injury.
                                         4



      HUH introduced the results of an independent medical examination conducted

in 2016 by Dr. Mark Scheer. Dr. Scheer relied on the Sixth Edition of the AMA

Guides, as well as his assessment of Mr. Lyles’s pain, weakness, atrophy, loss of

function, and loss of endurance. Dr. Scheer concluded that Mr. Lyles had a 4%

permanent impairment to his right upper extremity. According to Dr. Scheer, 2% of

the 4% impairment was preexisting and 2% was related to Mr. Lyles’s 2013 injury.



      The ALJ credited Mr. Lyles’s testimony and gave greater weight to Dr.

Menet’s opinion than to Dr. Scheer’s opinion. With one exception, the ALJ adopted

Dr. Menet’s calculations in determining the extent of Mr. Lyles’s disability. The

exception was that the ALJ did not accept the 10% impairment based on loss of

endurance, because Mr. Lyles had returned to full-time work as a radiological

technician/medical assistant. The ALJ therefore concluded that Mr. Lyles had

suffered a 37% permanent disability to his right upper extremity.



      The ALJ further concluded that HUH should be held responsible for all of the

impairment at issue, not solely the portion of the impairment that was caused by Mr.

Lyles’s most recent injury. The ALJ explained that apportionment of disability was

precluded by D.C. Code § 32-1508 (6)(A) (“If an employee receives an injury,
                                          5

which combined with a previous occupational or nonoccupational disability or

physical impairment causes substantially greater disability or death, the liability of

the employer shall be as if the subsequent injury alone caused the subsequent amount

of disability . . . .”).



       HUH argued to the ALJ that, in determining the amount of Mr. Lyles’s award

under § 32-1508 (3)(A) and (S), the ALJ should not consider the impairment to Mr.

Lyles’s shoulder, because the shoulder is not part of the arm. Relying on the decision

of the Compensation Review Board (CRB) in Lawson, CRB No. 14-056(R), 2017

WL 576074 (Jan 11, 2017), the ALJ concluded that the shoulder is part of the arm

for purposes of § 32-1508.



       HUH sought review before the CRB, which affirmed the ALJ’s compensation

order. Among other things, HUH argued that, in calculating the amount of Mr.

Lyles’s disability, the ALJ had not explained the connection between Mr. Lyles’s

physical impairments and the extent of Mr. Lyles’s disability.             The CRB

acknowledged that ALJs must specifically explain the nexus between physical-

impairment factors -- including pain, weakness, atrophy, loss of endurance, and loss

of function -- and a claimant’s “industrial capacity.” The CRB concluded, however,

that the ALJ had adequately explained his conclusions.
                                         6



      Finally, the CRB concluded that § 32-1508 (6)(A), the provision the ALJ

relied upon as precluding apportionment, had not been repealed by § 2 (e)(2) of the

Workers’ Compensation Amendment Act (WCAA). D.C. Act 12-571, 46 D.C. Reg.

891, 893-94 (1999). We discuss the CRB’s reasoning on that point more fully later

in this opinion.



                                         II.



      We review a decision of the CRB to determine whether the decision was

“arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with

law.” Reyes v. District of Columbia Dep’t of Emp’t Servs., 48 A.3d 159, 164 (D.C.

2012) (internal quotation marks omitted). “Our principal function in reviewing

administrative action is to assure that the agency has given full and reasoned

consideration to all material facts and issues.” Georgetown Univ. Hosp. v. District

of Columbia Dep’t of Emp’t Servs., 916 A.2d 149, 151 (D.C. 2007) (internal

quotation marks omitted). We must defer to the CRB’s reasonable interpretation of

statutes that the CRB is charged with administering. See, e.g., Pierce v. District of

Columbia Police & Firefighters’ Ret. & Relief Bd., 882 A.2d 199, 205 (D.C. 2005).
                                         7

                                         A.



      HUH argues that the award to Mr. Lyles should be reduced because some of

Mr. Lyles’s impairment was attributable to an earlier injury. HUH does not dispute

that § 32-1508 (6)(A) by its terms precludes apportionment of disability. Rather,

HUH argues that § 32-1508 (6)(A) was subsequently repealed, and an employer

therefore now must only compensate that portion of a claimant’s disability that is

attributable to a workplace injury that occurred during the claimant’s current

employment. We remand this issue for further consideration by the CRB.



      As enacted in 1980, the Workers’ Compensation Act (WCA) permitted

apportionment of disability, requiring a claimant’s current employer to compensate

the claimant for only the new portion of a disability that arose in part from a prior

injury and in part from a new injury. D.C. Act 3-188, § 9 (f), 27 D.C. Reg. 2503,

2516 (1980).     The WCA did provide for additional compensation in such

circumstances, but that compensation was paid by a special fund created for that

purpose. Id. Such funds, often called second-injury funds, have been a common

feature of modern workers’ compensation statutes. 8 Lex K. Larson & Thomas A.

Robinson, Larson’s Workers’ Compensation Law § 91.01 (2018).
                                           8

      The WCA was subsequently amended, however, in two pertinent respects.

First, in cases involving disability arising in part from prior injury and in part from

a subsequent injury, employers were made responsible “as if the subsequent injury

alone caused the subsequent amount of disability.” D.C. Code § 32-1508 (6)(A).

Thus, apportionment of disability was no longer permitted. Daniel v. District of

Columbia Dep’t of Emp’t Servs., 673 A.2d 205, 208 (D.C. 1996) (discussing

provision as previously codified at D.C. Code § 36-308 (6)(A) (1993 Repl.)).

Presumably to mitigate the effect of that change on employers, and to avoid creating

disincentives to the hiring of disabled workers, the WCA provided that the special

fund would reimburse employers for benefits paid after 104 weeks. D.C. Code § 32-

1508 (6)(A)(iii), (B).



      The provision currently at issue is § 2 (e)(2) of the WCAA, which provides

that “Section 9 (D.C. Code § 36-308) [of the WCA] is amended as follows: . . . A

new subsection (f)(3) is added to read as follows: ‘(3) The requirements of this

subsection shall apply to injuries occurring prior to the effective date of the Workers’

Compensation Amendment Act of 1998.’” 46 D.C. Reg. 893-94. Interpreting this

provision requires a brief detour into the terminology and practices of statutory

drafting and codification.
                                          9

      In drafting legislation, the D.C. Council, like the United States Congress,

“ordinarily adheres to a hierarchical scheme in subdividing statutory sections,” using

subsections starting with (a); paragraphs starting with (1); subparagraphs starting

with (A), and clauses starting with (i). Koons Buick Pontiac GMC, Inc. v. Nigh, 543

U.S. 50, 60-61 (2004).      Applying that convention to the WCA as enacted,

subdivision (f) of § 9 of the WCA is a subsection. The provision of the WCAA at

issue, § 2 (e)(2), by its terms makes the requirements of § 9 (f) inapplicable to

injuries that occur after the effective date of the WCAA. Thus, as the CRB

acknowledged, § 2 (e)(2) of the WCAA by its terms appears to apply to the entire

subsection of the WCA that addressed apportionment. Cf., e.g., NLRB v. SW Gen.,

Inc., 137 S. Ct. 929, 938-39 (2017) (statutory cross-reference to section included all

subsections of section). That would seemingly include the provision (now codified

at D.C. Code § 32-1508 (6)(A)) that the ALJ relied upon as precluding

apportionment.



      We pause to note a complication created by the way in which the WCA has

been codified.   As currently codified, § 32-1508 is unconventionally labelled.

Rather than having subsections labelled with lower-case letters starting with (a),

§ 32-1508 is initially subdivided using Arabic numerals starting with (1). D.C. Code

§ 32-1508. The codifier thus appears to have codified § 32-1508 as having no
                                        10

subsections, making § 32-1508 (6) a paragraph. Presumably for that reason, the

codifier changed the word “subsection” in § 2 (e)(2) of the WCAA to “paragraph”

when codifying § 2 (e)(2). D.C. Code § 32-1508 (6)(C). It is a standard practice for

codifiers to make conforming changes, including changes to cross-references. See

generally Linda W. Cropp & Charlotte Brookins-Hudson, Preface to the 2001

Edition of the D.C. Official Code vi (2012 Repl.) (D.C. Council’s Office of General

Counsel codifies enactments of D.C. Council, including “interpret[ing] any

discrepancies in the drafting of the laws[,] using commonly recognized rules of

statutory construction”); 2 U.S.C. § 285b(4) (2017) (duties of federal Office of the

Law Revision Counsel include “classify[ing] newly enacted provisions of law to

their proper positions in the Code”). That appears to be what the codifier did in

codifying § 2(e)(2) of the WCAA. As codified, that provision is a subparagraph,

§ 32-1508 (6)(C), that by its terms prospectively repealed the requirements in the

rest of paragraph (6), including § 32-1508 (6)(A) and (B).



      As noted, the CRB acknowledged that § 32-1508 (6)(C) by its terms could be

read to have prospectively repealed all of § 32-1508 (6). Nevertheless, relying

primarily on the WCAA’s lengthy title (which the CRB referred to as a preamble),

the CRB concluded that the D.C. Council had intended only to repeal the special

fund that provided reimbursement to employers in cases involving disability that
                                          11

arose in part from a prior injury and in part from a new injury, and that the D.C.

Council had not intended to “[b]ring[] apportionment into the picture.” See 46 D.C.

Reg. 891 (1999) (WCAA’s title refers in pertinent part “to repeal [of] the subsequent

injury fund provisions with respect to injuries occurring after the effective date of

this act”; no mention of apportionment of disability). By itself, however, the title of

the WCAA is not a sufficient basis upon which to decline to give effect to the plain

language of the text of § 2 (e)(2). See, e.g., Mitchell v. United States, 64 A.3d 154,

156 (D.C. 2013) (title of provision “cannot limit the plain meaning of the text”)

(internal quotation marks omitted); see also, e.g., District of Columbia v. Heller, 554

U.S. 570, 578 n.3 (2008) (“[I]n America the settled principle of law is that the

preamble cannot control the enacting part of the statute in cases where the enacting

part is expressed in clear, unambiguous terms.”) (internal quotation marks omitted).



      In this court, HUH argues among other things that repealing the special-injury

fund while still precluding apportionment is bad policy and requires subsequent

employers to bear the expense of excessive disability payments to workers. HUH

also argues that the CRB treated § 2 (e)(2) as prospectively repealing only § 32-

1508 (6)(B), which addresses the special-fund reimbursement, without considering

whether § 2 (e)(2) also prospectively repealed § 32-1508 (6)(A)(iii). As previously

noted, in cases in which a claimant’s current disability rests in part on a prior
                                         12

disability, the latter provision appears to limit the extent of the current employer’s

obligation to pay monetary benefits to 104 weeks. D.C. Code § 32-1508 (6)(A)(iii).

Thus, HUH argues, if only § 32-1508 (6)(B) was repealed, claimants in such cases

would be limited to 104 weeks’ compensation and thus might not receive full

compensation. The CRB did not explicitly address whether § 2 (e)(2) of the WCAA

also repealed § 32-1508 (6)(A)(iii).



      We conclude that the matter must be remanded for the CRB to further consider

the proper interpretation of § 2(e)(2) of the WCAA and its implications for

apportionment under the WCA. As we have noted, the CRB in this case relied

primarily on the title to the WCAA, which by itself cannot provide a basis for

disregarding clear textual language. In a subsequent decision, the CRB discussed

the issue somewhat more fully, taking into account the legislative history of the

WCAA and discussing underlying considerations of policy. Brown, CRB No. 16-

020(R), 2018 WL 4854481, at *4-6 (Sept. 5, 2018). Nevertheless, neither in this

case nor in Brown did the CRB address the questions posed by the interaction of

§ 2 (e)(2) of the WCAA and D.C. Code § 32-1508 (6)(A)(iii). “[A]cknowledging

the CRB’s expertise and responsibility for administering the [WCA],” we “remand[]

the case to enable the CRB to consider [that issue] in the first instance.” Levy v.

District of Columbia Dep’t of Emp’t Servs., 84 A.3d 518, 521 (D.C. 2014) (brackets
                                              13

and internal quotation marks omitted). We express no view on the proper resolution

of that issue.



                                              B.



       HUH also challenges the CRB’s conclusion that the shoulder is part of the

arm for purposes of D.C. Code § 32-1508 (3)(A) and (S). We agree with HUH’s

challenge.



       By way of background,

                 The Workers’ Compensation Act divides permanent
                 partial disabilities into two categories, “schedule” and
                 “non-schedule.” Schedule disabilities are those involving
                 the loss or impairment of certain specified body parts, e.g.,
                 the loss of an arm, leg, or eye. For each such injury, a
                 worker is entitled to receive 66 2/3% of his or her average
                 weekly wages for a fixed number of weeks that varies
                 depending on the particular body part injured . . . ,
                 regardless of the actual wage loss the worker sustains as a
                 result of the injury.

Brown v. District of Columbia Dep’t of Emp’t Servs., 83 A.3d 739, 743 n.6 (D.C.

2014). If a claimant loses partial use of a specified body part, the claimant is entitled

to compensation in proportion to the degree of loss of use. D.C. Code § 32-

1508 (3)(S). In determining the degree of loss of use of a schedule body part, the

following factors may be considered: the most recent edition of the AMA Guides,
                                           14

pain, weakness, atrophy, loss of endurance, and loss of function. D.C. Code § 32-

1508 (3)(U-i). “In contrast, for other partially disabling injuries (i.e., to parts of the

body not listed in the ‘schedule,’ such as the back or neck), the worker’s disability

compensation is measured by his or her actual or imputed wage loss attributable to

the injuries. See D.C. Code § 32–1508 (3)(V).” Brown, 83 A.3d at 743 n.6.



      In the present case, Mr. Lyles sought a schedule award under D.C. Code § 32-

1508 (3)(A) and (S), which govern the partial loss of use of an arm. Some of the

impairments upon which Mr. Lyles relied were to Mr. Lyles’s shoulder.                  To

determine the degree to which Mr. Lyles lost the use of his arm, it thus was necessary

to decide whether the shoulder is properly understood to be part of the arm for the

purpose of determining a schedule award.



      In M.C. Dean, Inc. v. District of Columbia Department of Employment

Services, 146 A.3d 67, 70-75 (D.C. 2016), this court addressed a case in which the

CRB appeared to have treated the shoulder as part of the arm for the purpose of

determining a schedule award. The court noted, however, that “the Department of

Employment Services has previously interpreted the [WCA] to exclude the neck and

shoulder from schedule arm awards.” Id at 73. We therefore remanded the case for

the CRB to “clarify the definition[] of ‘arm.’” Id. at 75.
                                          15



      On remand in the Dean case, the CRB concluded that the arm includes the

shoulder for the purpose of determining a schedule award. Lawson, 2017 WL

576074, at *8. In the present case, the CRB relied upon in its earlier conclusion in

Lawson, so our focus is on the CRB’s analysis in Lawson. In Lawson, the CRB

noted that the WCA provides that the AMA Guides may be considered in

“determining disability.” Id. at *5 (quoting D.C. Code § 32-1508 (3)(U-i)). For

purposes of analyzing impairment, the AMA Guides use the term “upper

extremit[y]” rather than “arm,” and they define the upper extremity to include four

regions: the shoulder region, the elbow region, the wrist region, and the digit/hand

region. Id. at *6. Thus, the CRB concluded, “it is reasonable to infer that by making

the [AMA] Guides an appropriate benchmark for assessing objective medical

impairment, [the D.C.] Council intended that the anatomical description of the

relevant body parts referenced in the [AMA] Guides would correspond to the

anatomical body parts listed in the schedule.” Id. at *8. The principal difficulty with

this line of reasoning is that the body parts referenced in the AMA Guides do not

correspond to the body parts listed in the schedule in D.C. Code § 32-1508 (3)(A)-

(Q). Specifically, the AMA Guides include the hand and fingers as part of the upper

extremity, Lawson, 2017 WL 576074, at *6, but the hand and fingers are treated

separately from the arm under the statutory schedule, D.C. Code § 32-1508 (3)(A),
                                           16

(C), (F), (G), (I), (J), (L) (separate provisions specifying amounts of compensation

for loss of arm, hand, and fingers). The D.C. Council thus could not reasonably be

understood to have intended for the anatomical divisions used in the AMA Guides

to determine the interpretation of the anatomical terms used in the statutory schedule.

Rather, the D.C. Council appears to have intended that the AMA Guides would be

used in determining the degree of disability. We therefore are not persuaded by the

CRB’s reason for concluding that the shoulder should be treated as part of the arm.



      Mr. Lyles advances an additional argument in support of the CRB’s

conclusion. According to Mr. Lyles, “[t]he CRB concluded that sound public policy

supports finding the shoulder is part of the arm, because the CRB has focused more

and more on the place of functional disability, rather than the situs of injury, to assign

disability under the [WCA].” Mr. Lyles’s argument rests on a misunderstanding of

the CRB’s ruling in Lawson. In the passage from Lawson on which Mr. Lyles relies,

the CRB described the competing arguments of the parties, without adopting those

arguments. 2017 WL 576074, at *7. In general, an administrative order cannot be

affirmed on grounds not relied upon by the agency. E.g., Douglas-Slade v. U.S.

Dep’t of Transp., 959 A.2d 698, 702 (D.C. 2008). In any event, the argument

presented by the employer in Lawson conflates two distinct issues. It is well settled

under our law that a claimant who suffers an injury to a part of the anatomy that is
                                          17

not listed in the statutory schedule may nevertheless seek recovery under the

schedule if the consequence of that injury is the total or partial loss of use of a part

of the anatomy that is listed in the statutory schedule. See, e.g., M.C. Dean, Inc.,

146 A.3d at 73 (“[I]t is not the situs of the injury which determines whether a

schedule award is payable; it is the situs of the disability resulting from the injury

which is controlling.”) (internal quotation marks omitted).         Thus, even if the

shoulder is not considered part of the arm, injury to the shoulder might provide a

basis for a schedule award based on total or partial loss of use of the arm. Moreover,

if the shoulder is not part of the arm, then a claimant who suffers injury to the

shoulder would also have the option of seeking an unscheduled award by showing

actual or imputed wage loss attributable to that injury. D.C. Code § 32-1508 (3)(V).

In light of these considerations, we do not perceive a clear public-policy rationale

that would necessitate treating the shoulder as part of the arm.



      Two other considerations bear on the CRB’s conclusion that the shoulder

should be considered part of the arm. First, dictionary definitions of “arm” often

refer somewhat ambiguously to the upper limb of the human body, but when they

are anatomically specific they often exclude the shoulder. See, e.g., Webster’s Third

New International Dictionary, Unabridged 118 (2002) (defining “arm” as “(1) a

human upper limb; (2) the part of an arm between the shoulder and the wrist”);
                                          18

American Heritage Dictionary of the English Language 100 (3d ed. 1992) (“An

upper limb of the human body, connecting the hand and wrist to the shoulder.”). Cf.

generally, e.g., O’Rourke v. District of Columbia Police & Firefighters’ Ret. &

Relief Bd., 46 A.3d 378, 383 (D.C. 2012) (“The first step in construing a statute is to

read the language of the statute and construe its words according to their ordinary

sense and plain meaning.”) (internal quotation marks omitted).




      Second, the substantial weight of authority appears to support treating the

shoulder as distinct from the arm for the purpose of determining a schedule award

of workers’ compensation benefits. See, e.g., Keenan v. Dir. for Benefits Review

Bd., 392 F.3d 1041, 1045 (9th Cir. 2004) (shoulder is not part of arm); Taylor v.

Goodyear Tire & Rubber Co., 37 So. 3d 813, 820 (Ala. Civ. App. 2009) (“the

shoulder is not part of the arm”) (internal quotation marks omitted); Safeway Stores,

Inc. v. Indus. Comm’n, 558 P.2d 971, 974 (Ariz. Ct. App. 1976) (“the shoulder is a

distinct anatomical entity, not part of the arm”) (citing cases); Safford v. Owens

Brockway, 816 A.2d 556, 561 (Conn. 2003) (shoulders are “an unscheduled body

part”); Jewell v. Wood, 130 So. 2d 277, 278 (Fla. 1961) (injury to shoulder is not

injury to arm); Gentry v. Ga. Cas. & Sur. Co., 131 S.E.2d 788, 790 (Ga. Ct. App.

1963) (“The shoulder, as we construe the law, is not a part of the arm.”); Will Cty.

Forest Preserve Dist. v. Ill. Workers’ Comp. Comm’n, 970 N.E.2d 16, 24 (Ill. App.
                                           19

Ct. 2012) (“the shoulder is not part of the arm”) (citing cases); Second Injury Fund

v. Nelson, 544 N.W.2d 258, 269-70 (Iowa 1995) (injury to shoulder is not schedule

injury); Getson v. WM Bancorp, 694 A.2d 961, 964-69 (Md. 1997) (“shoulder

injuries are unscheduled”) (citing cases); Foster v. State Accident Ins. Fund, 485

P.2d 407, 408-09 (Or. 1971) (treating shoulder as unscheduled body part); Cont’l

Ins. Cos. v. Pruitt, 541 S.W.2d 594, 595-96 (Tenn. 1976) (shoulder is not part of

arm). We note that workers’ compensation law in some of the cited jurisdictions

differs in important respects from the law in this jurisdiction. By citing the foregoing

cases for the specific principle at issue in this case, we do not mean to imply

endorsement of the holdings of those cases on other issues.




      We are aware of three jurisdictions that treat the shoulder as a schedule body

part, but in each of those jurisdictions the statutory schedule specifically refers to the

shoulder. Strauch v. PSL Swedish Healthcare Sys., 917 P.2d 366, 367 (Colo. App.

1996) (“loss of an arm at the shoulder”); Mitchell v. Petsmart, Inc., 239 P.3d 51, 60

(Kan. 2010) (“loss of an arm, including the shoulder joint, shoulder girdle, shoulder

musculature or any other shoulder structures”); Hagen v. Labor & Indus. Review

Comm’n, 563 N.W.2d 454, 457 (Wis. 1997) (“loss of an arm at the shoulder”).
                                          20

      For the foregoing reasons, we are not persuaded that the CRB has articulated

a reasonable basis for treating the shoulder as part of the arm when determining a

schedule award. To the contrary, we conclude that the CRB’s decision to treat the

shoulder as part of the arm was unreasonable as a matter of law. Cf. generally, e.g.,

District of Columbia Office of Human Rights v. District of Columbia Dep’t of Corr.,

40 A.3d 917, 923 (D.C. 2012) (concluding that agency interpretation of statute was

unreasonable as matter of law). We therefore vacate the order of the CRB and

remand for further proceedings focused on the degree to which Mr. Lyles has lost

the use of his arm, not including the shoulder. We reiterate, however, that Mr. Lyles

is not foreclosed from relying on impairments of his shoulder that have as their

consequence partial or total loss of the use of his arm.




                                          C.



      HUH finally argues that the CRB erred by concluding that, in calculating the

amount of the award, the ALJ adequately explained the connection between Mr.

Lyles’s physical impairments and the extent of Mr. Lyles’s disability. We agree.



      Here too some background is necessary. If a claimant suffers total loss of a

schedule body part, or total loss of use of a body part, the WCA provides a set
                                          21

amount of compensation, generally 66⅔% of the claimant’s average weekly wages

for a specified duration that varies depending on the body part at issue. D.C. Code

§ 32-1508 (3)(A)-(R). A claimant seeking such an award is not required to introduce

any evidence about the actual or likely effect of the loss on the claimant’s wages or

employment prospects. E.g., Smith v. District of Columbia Dep’t of Emp’t Servs.,

548 A.2d 95, 101 (D.C. 1988). As we explained in Smith,

             The typical schedule, limited to obvious and easily-
             provable losses of [schedule body parts], was justified on
             two grounds: the gravity of the impairment supported a
             conclusive presumption that actual wage loss would
             sooner or later result; and the conspicuousness of the loss
             guaranteed that awards could be made with no controversy
             whatsoever. Although impaired earning capacity need not
             be proved to receive schedule benefits, this is not to be
             interpreted as an erratic deviation from the underlying
             principle of compensation law—that benefits relate to loss
             of earning capacity and not to physical injury as such. The
             basic theory remains the same; the only difference is that
             the effect on earning capacity is a conclusively presumed
             one, instead of a specifically proved one based on the
             individual’s actual wage-loss experience.

Id. (ellipsis, citation, brackets, and internal quotation marks omitted).



      A claimant may also seek a schedule award based on partial loss of use of a

schedule body part. D.C. Code § 32-1508 (3)(S). As previously noted, the WCA

generally provides that six factors may be considered in determining disability for

purposes of schedule awards: the AMA Guides, pain, weakness, atrophy, loss of
                                          22

endurance, and loss of function. D.C. Code § 32-1508 (U-i). Those factors thus are

relevant to determining the degree of partial loss of use. Our cases indicate,

however, that the amount of a partial-loss schedule award is not properly determined

based solely on a non-economic medical determination as to the degree of physical

impairment of the body part at issue. Negussie v. District of Columbia Dep’t of

Emp’t Servs., 915 A.2d 391, 399 (D.C. 2007) (“‘[D]isability’ is an economic and

legal concept which should not be confounded with a medical condition . . . .”).

Rather, in the context of partial-loss schedule awards, we have stated that

“compensation under the [WCA] is predicated upon the loss of wage earning

capacity, or economic impairment, and not upon functional disability or physical

impairment.” Dent v. District of Columbia Dep’t of Emp’t Servs., 158 A.3d 886,

901 (D.C. 2017) (internal quotation marks omitted). We also have said that the six

statutory factors “may be considered by the ALJ and the CRB in making a schedule

award for permanent partial disability to compensate for loss of wage-earning

capacity.” Id. at 902; see also id. at 903 (“The ALJ’s ability to come to a considered

judgment of the extent of permanent partial disability is particularly important in the

context of a schedule award. Because a schedule award is a one-time payment meant

to compensate for the loss of future wage-earning capacity resulting from a work

injury, it necessarily involves an element of prediction. Determining the extent of

disability thus requires a highly fact-bound inquiry that takes into account the
                                        23

particulars of the individual claimant, such as employment skills, experience, age,

education, and reasonable prospects; evidence of post-injury wages, compared with

pre-injury wages, may be more or less probative of loss of future wage-earning

capacity depending on the facts of the case. It is for the ALJ to consider and weigh

the relevant evidence presented in a given case.”) (citation and internal quotation

marks omitted).



      As previously noted, Dr. Menet concluded that Mr. Lyles had a 47%

permanent impairment to his right upper extremity, based on the following specific

impairments: 3% based on lack of full motion, 12% for pain, 10% for weakness,

12% for loss of function, and 10% for loss of endurance. Dr. Menet did not tie those

calculations to predictions about Mr. Lyle’s future wage-earning capacity. The ALJ

accepted Dr. Menet’s calculations, with one exception: the ALJ did not accept the

10% impairment based on loss of endurance, because Mr. Lyles had returned to full-

time work as a radiological technician/medical assistant.      The ALJ therefore

concluded that Mr. Lyles had suffered a 37% permanent disability to his right upper

extremity. The ALJ did not explain how Dr. Menet’s other calculations related to

Mr. Lyles’s future wage-earning capacity.
                                         24

      The CRB acknowledged that ALJs must specifically explain the nexus

between the statutory factors of pain, weakness, atrophy, loss of endurance, and loss

of function and a claimant’s “industrial capacity.” (The CRB has equated “industrial

capacity” and “wage-earning capacity.” Dent, 158 A.3d at 898 (internal quotation

marks omitted).) The CRB concluded, however, that the ALJ had adequately

explained his conclusions. We do not agree. The ALJ did not explain the likely

consequences, if any, that Mr. Lyles’s physical impairments would have for Mr.

Lyles’s wage-earning capacity. We therefore must remand for the ALJ to provide

the necessary explanation. See generally, e.g., Bowles v. District of Columbia Dep’t

of Emp’t Servs., 121 A.3d 1264, 1269 (D.C. 2015) (“When the ALJ fails to explain

its reasoning in arriving at a disability award[,] such that we are unable to

meaningfully review the decision to determine whether it is based on substantial

evidence, we must remand the case back to the CRB.”) (brackets and internal

quotation marks omitted).



      For the foregoing reasons, we vacate the order of the CRB and remand the

case for further proceedings.



                                So ordered.
