United States Court of Appeals
                             FOR THE EIGHTH CIRCUIT
                                ________________

                                   No. 98-2274
                                ________________

Michael A. Pfitzner,                      *
                                          *
             Appellant,                   *
                                          *       Appeal from the United States
      v.                                  *       District Court for the
                                          *       Western District of Missouri.
Kenneth S. Apfel, Commissioner of         *
Social Security,                          *
                                          *
             Appellee.                    *

                                ________________

                                Submitted: November 20, 1998
                                    Filed: March 1, 1999
                                ________________

Before McMILLIAN, WOLLMAN, and HANSEN, Circuit Judges.
                       ________________

HANSEN, Circuit Judge.

      Michael A. Pfitzner appeals the district court's affirmance of the
Commissioner's denial of Social Security benefits. Because the Administrative Law
Judge (ALJ) made no specific findings as to Pfitzner's residual functional capacity
and the requirements of his past relevant work, we hold that substantial evidence does
not support the denial of benefits. Accordingly, we reverse and remand.
                                           I.

       Pfitzner applied for Social Security Benefits in March 1995, claiming that he
had been disabled since June 1, 1994, even though he continued to work after that
date. The Social Security Administration denied his request both initially and upon
reconsideration. On April 30, 1996, an ALJ heard Pfitzner's case, and on June 7,
1996, the ALJ issued a decision denying Pfitzner's claim. The Appeals Council
denied his request for review. After exhausting his administrative remedies, Pfitzner
filed this action. The district court granted the Commissioner's motion for summary
judgment and affirmed the denial of benefits.

       Pfitzner was 48 years old at the time of his hearing. He had previously worked
as a truck driver and a maintenance person. Pfitzner initially claimed that arthritis
and hypertension caused his disability. Before the ALJ, however, he also argued that
he suffered from depression and ulcers.

      The record contains a fair amount of medical history, but the opinions and
diagnoses of four doctors are most relevant. Doctor Ralph Schmitz attended to
Pfitzner's medical needs many times between 1992 and 1996. Dr. Schmitz treated
Pfitzner for multiple ailments and complaints including joint problems, pain
management, hypertension, and depression. In April 1995, almost one year after the
alleged onset of Pfitzner's disability, Dr. Schmitz concluded that Pfitzner could
continue to work.

      Doctor Stanley Hayes, a rheumatologist, evaluated Pfitzner's joint-related
problems in May 1995, and again in February 1996. Dr. Hayes concluded that
Pfitzner would be better suited to work that required less standing time and had
reduced arm usage. Dr. Hayes further concluded that Pfitzner's degenerative disc
disease did not adequately explain his joint pain, and opined that Pfitzner's depression
was his "overpowering problem."

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       Doctor Paul Dobard, a psychiatrist, saw Pfitzner in March and April 1996. In
a progress note dated April 1, 1996, Dr. Dobard diagnosed Pfitzner as suffering from
major depression with anxiety. On May 9, 1996, however, Dr. Dobard prepared a
Medical/Psychological Source Statement - Mental suggesting that Pfitzner's mental
limitations were moderate to nonexistent. Of the twenty categories identified on the
Source Statement, Dr. Dobard found Pfitzner "not significantly limited" in fifteen
categories, "moderately limited" in two categories, and "not ratable" in three
categories.

       Doctor Rex Peterson, an osteopath, evaluated Pfitzner after the ALJ's decision.
Dr. Peterson diagnosed Pfitzner as suffering from several orthopaedic problems
including degenerative arthritis in both ankles. Dr. Peterson's notes indicate that
prednisone helped to control Pfitzner's pain. At some point, Dr. Peterson signed an
undated form in support of Pfitzner's application for a disabled person's license plate.
Although the form included no substantiating analysis or other specific information,
it identified Pfitzner as being permanently disabled.

        Pfitzner, his friend Dale Kennedy, and Michael Wiseman, a vocational expert,
testified before the ALJ. Pfitzner identified a host of physical and mental problems.
He testified that he could walk only 25 steps before his ankles hurt, stand for about
five minutes, sit with his feet down for about four minutes, and lift five pounds.
When asked about his depression, Pfitzner attributed much of his problem to his
financial situation and noted that a fire had recently destroyed his house. Most of
Dale Kennedy's testimony, albeit largely hearsay, corroborated Pfitzner's subjective
complaints. Kennedy admitted that he and Pfitzner worked together on Pfitzner's
farm, but that it sometimes took both men to load a single hay bale.

      The ALJ presented the vocational expert with one long hypothetical that
included virtually any limitation supported by the objective evidence and Pfitzner's
subjective complaints. It reflected a person of Pfitzner's age, education, and

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experience. It further reflected a person having, inter alia, arthritis, depression,
degenerative joint disease, ulcers, and hypertension. The vocational expert testified
that such a person could not work.

      The ALJ's decision followed the familiar five-step model. See 20 C.F.R. §
404.1520 (1998). See also Baker v. Apfel, 

, 1143-44 (8th Cir. 1998).
The ALJ terminated the inquiry after step four, finding that Pfitzner retained the
residual functional capacity to return to his past work as a truck driver.

                                          II.

      "Our standard of review is a narrow one. We will affirm the ALJ's findings if
supported by substantial evidence on the record as a whole." 

. Substantial evidence exists if a reasonable mind would find such evidence
adequate. 

review we undertake is more than an examination of the
record for the existence of substantial evidence in support of the Commissioner's
decision, we also take into account whatever in the record fairly detracts from that
decision." 

his conclusion that Pfitzner retained the residual functional
capacity to return to his past relevant work, the ALJ recounted most of the relevant
medical evidence in the record. Unfortunately, the ALJ never specifically articulated
Pfitzner's residual functional capacity, rather he described it only in general terms.
Near the end of his decision, for example, the ALJ stated that Pfitzner "retain[ed] the
residual functional capacity to perform a wide range of medium work." (Rec. at 29.)
In his findings, the ALJ stated that Pfitzner retained the "capacity to perform work
related activities except for work involving limitations described in the body of this
decision." (Id. at 30.) Pfitzner takes issue with the ALJ's treatment of his residual
functional capacity. Specifically, Pfitzner contends that the ALJ's fact-findings on
this issue are incomplete or nonexistent. We agree.

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       "An ALJ's decision that a claimant can return to his past work must be based
on more than conclusory statements. The ALJ must specifically set forth the
claimant's limitations, both physical and mental, and determine how those limitations
affect the claimant's residual functional capacity." Groeper v. Sullivan, 

, 1238-39 (8th Cir. 1991). The Administration's own interpretation of the
regulations reflects this need for specificity. The determination that a "claimant
retains the functional capacity to perform past work . . . has far-reaching implications
and must be developed and explained fully in the disability decision." S.S.R. No. 82-
62, 

, *3 (Ruling 82-62). See also Sells v. Shalala, 

,
1046 (8th Cir. 1995) (discussing Ruling 82-62). "This court has held, consistent with
Ruling 82-62, that '[a] conclusory determination that the claimant can perform past
work, without these findings, does not constitute substantial evidence that the
claimant is able to return to his [or her] past work.'" 

932 F.2d
at 1239).

      Over the course of several pages, the ALJ dutifully discussed the relevant
evidence, yet he articulated only the outermost contours of Pfitzner's residual
functional capacity. While it is clear that the ALJ found Pfitzner's mental problems
moderate and limited to situational depression (see Rec. at 30), the specifics of
Pfitzner's physical limitations are not so easily gleaned from the ALJ's decision.
Perhaps the ALJ found that Pfitzner had no significant physical limitations. One
might infer such a finding from the ALJ's conclusion that "[t]he medical evidence
reveals no specific physician imposed physical limitations." (Id. at 29.) Even on our
deferential review of the ALJ's decision, we cannot say that substantial evidence
supports such a conclusion. Dr. Hayes, a rheumatologist, concluded that Pfitzner's
"employment would be better suited for him if he were on his feet less and had less
requirements for using his arms." (Id. at 152.) In fact, even the ALJ found that the
evidence established that Pfitzner suffered from arthritis. (Id. at 30.) And although
Dr. Schmitz concluded at one point that Pfitzner could continue to work, he provided
no details indicating what, if any, physical limitations should be placed on Pfitzner's

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work activities. Thus, substantial evidence would not support a conclusion that
Pfitzner suffered no physical limitations. Because the ALJ failed to specify the
details of Pfitzner's residual functional capacity, we cannot say that substantial
evidence supports his conclusion that Pfitzner retained the functional capacity to
return to his past work. See 

.

       Defining a claimant's residual functional capacity is not the only task required
at step four. "The ALJ must also make explicit findings regarding the actual physical
and mental demands of the claimant's past work." 

. The
ALJ may discharge this duty by referring to the specific job descriptions in the
Dictionary of Occupational Titles that are associated with the claimant's past work.
See 

. Pfitzner asserts that the ALJ erred in this regard as well.
We agree.

       The ALJ made no specific findings as to the detailed demands of Pfitzner's past
relevant work. Nor did the ALJ expressly refer to the Dictionary of Occupational
Titles. One could arguably conclude that the ALJ implicitly referred to the Dictionary
of Occupational Titles when he stated that "[t]he job of truck driver is described as
semiskilled, medium work." (Rec. at 29.) We think, however, that the lack of an
express reference reflects more than a mere deficiency in opinion-writing in this case.
Cf. McGinnis v. Chater, 

, 875 (8th Cir. 1996) (noting that asserted errors
in opinion-writing do not require a reversal if the error has no effect on the outcome).
The Dictionary of Occupational Titles contains several job titles that relate to truck
driving, each identifying different job requirements. The ALJ's decision leaves to
speculation which of these job descriptions reflects Pfitzner's past relevant work. As
such, we simply cannot say that substantial evidence supports the ALJ's decision. See

.




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                                         III.

       Because the ALJ failed to make the required specific findings as to Pfitzner's
residual functional capacity and past work demands, we cannot say that substantial
evidence supports the Commissioner's denial of benefits. In view of our decision, we
need not address the other issues raised in Pfitzner's briefs. We recognize that the
ALJ's decision may not change after properly considering and documenting Pfitzner's
residual functional capacity and past work demands. See 

.
We also recognize that the ALJ may choose to extend his inquiry through the fifth
step and find that Pfitzner can perform work other than his past relevant work. Those
considerations, however, do not alter our conclusion that the record before us does
not support the ALJ's decision that Pfitzner retains the functional capacity to return
to his past work. We reverse the district court's judgment in favor of the
Commissioner, and we remand the matter with instructions to remand the case to the
Commissioner for additional proceedings consistent with this opinion.

      A true copy.

             Attest:

                     CLERK, U.S. COURT OF APPEALS, EIGHTH CIRCUIT




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