The employee petitions this court to vacate an award on stipulation served and filed in this case on October 25, 1989, on grounds that his condition has substantially worsened since the issuance of the award.  Finding sufficient basis to vacate the award on stipulation, we grant the petition.

On June 8, 1989, Michael Gruye [the employee] was employed by Triangle Maintenance [the employer] as a maintenance worker.  On that date, the employee allegedly sustained a personal injury arising out of and in the course of his employment when he was assaulted by a coworker.  The police were called and the employee was transported by ambulance to Hennepin County Medical Center [HCMC], where he was treated for contusions and released.  About three weeks later, the employee filed a claim petition seeking payment for wage loss benefits from June 8, 1989, to June 13, 1989, and medical benefits for his treatment at HCMC.  The employer and its insurer denied liability for the assault, contending specifically that the “claimed injury arose out of reasons personal to the Employee, not within the course and scope of his employment with [the employer].”  Following the incident, the employee apparently was placed on suspension by the employer and was ultimately terminated effective July 11, 1989.  The employee was thirty years old at the time of his alleged injury and, according to the parties’ subsequent stipulation for settlement, was earning a weekly wage of $254.00.

On August 21, 1989, the employee was seen in follow-up at HCMC.  The examining physician found “no physical sequelae” from the assault but noted that the employee still reported some emotional anguish stemming from the incident.  The doctor made a referral for counseling.  Two days later, the employee’s attorney, David Forro, forwarded the doctor’s evaluation note to William Hauck, counsel for the employer and insurer.  Noting that the doctor reported “no residual physical injuries from the assault,” Mr. Forro requested that Mr. Hauck prepare a stipulation for settlement.  Mr. Forro stated that his client understood that the settlement would be “full, final and complete.”  He included with his letter a summary of charges paid by Blue Cross and Blue Shield, which did not include charges for the “final medical exam” on August 21, 1989.

On September 29, 1989, the employee was seen at HCMC by social worker Bruce Atherton, complaining of run-on thinking, sleep disturbance, and lethargy.  The employee reported, “I can’t seem to get myself together since I was assaulted in June this year.”  Mr. Atherton assessed chronic moderate depression with co-dependent personality characteristics, and he recommended weekly counseling and a referral to the Hennepin County Mental Health Center for assessment of the need for medication.

The parties entered into a Stipulation for Settlement in October 1989.  At the time of the settlement, the employee contended that he was entitled to one week of temporary total disability benefits, “plus . . . medical expenses incurred as a result of [the] assault.”  The employer and insurer denied liability for any work injury and alleged that the claimed assault “was a result of a personal dispute that the Employee had with his unknown assailant, and not the result of his work activities or work associations or conditions while employed at [the employer].”  The stipulation did not identify the nature of the injuries claimed by the employee.  Under the terms of the stipulation, the employee was paid $195.00, less attorney fees, for a full, final, and complete settlement of all claims arising out of the alleged incident of June 8, 1989.  The employer and insurer also agreed to pay the employee’s claimed medical expenses of $825.60.^[1] As part of the settlement, the employer and insurer specifically maintained their denial of liability for the claimed injury, maintaining also that the employee had made a full recovery from his alleged injuries.  An award on stipulation was served and filed on October 25, 1989.

Over the next ten months following his workers’ compensation settlement, the employee was seen by a number of mental health professionals at HCMC.  On March 12, 1990, the employee was seen for medication assessment by psychiatrist Dr. Carlos Schenck.  Dr. Schenck diagnosed major depression and recommended a trial of Prozac.  The medication caused severe sleep disruption, and the employee ceased taking it after about two months.  When he last saw the employee on September 4, 1990, Dr. Schenck did not believe that the employee required an antidepressant medication, and instead he recommended that the employee pursue psychotherapy.

About three months later, the employee was seen for a psychiatric evaluation by Dr. Alford Karayusuf at the request of the Social Security Administration.  The employee reported that he was currently under the care of his family physician, Dr. Michael Pleasants, who was prescribing Prozac and Pamelor.  Dr. Karayusuf diagnosed major depression, in partial remission, and mixed personality disorder, with dependent, passive aggressive, immature, and schizoid features.  Shortly thereafter, on January 8, 1991, the employee was notified that he had been found disabled by the Social Security Administration as of June 26, 1989, and was being awarded benefits dating back to December 1989.

Following the psychiatric evaluation by Dr. Karayusuf, the employee began psychotherapy sessions with licensed psychologist Gary Donaldson, evidently one of Dr. Karayusuf’s associates.  In a letter to the employee’s attorney, Gregory Johnston, on April 16, 1991, Mr. Donaldson diagnosed chronic depressive illness and borderline personality disorder.  It was his opinion that the employee had probably suffered from both conditions prior to the assault.  He noted, however, that, according to his self-report, the employee has felt much worse as a result of the assault.

In a letter to Mr. Johnston on October 28, 1992, Mr. Donaldson clarified his earlier opinions by stating that the employee’s preexisting personality disorder was substantially and permanently aggravated by the physical injuries that he sustained in the assault.  He related the employee’s depressive illness directly to the work incident, and he opined that both that illness and the employee’s borderline personality disorder were substantial factors in the employee’s disability and his inability to return to gainful employment.  Mr. Donaldson rated the employee’s whole body permanent partial disability at 30%, based upon Minnesota Rules 5223.0060, subpart. 8.E.(2).

On November 23, 1992, the employee filed with this court a petition to vacate the 1989 award on stipulation, based on a substantial change in medical condition.  The employee claimed that, since the award on stipulation, he had been diagnosed as suffering from chronic depressive illness and borderline personality disorder secondary to his work-related assault.  These conditions, he contended, which rendered him totally disabled from gainful employment, had not manifested themselves prior to the settlement.  In a decision issued December 11, 1992,^[2] a panel of this court noted that the only medical evidence submitted in support of the petition was various reports from psychologist Donaldson, dating from April 16, 1991.  While acknowledging Mr. Donaldson’s opinions, the court noted that those opinions were based at least in part on the employee’s own report regarding his past psychiatric history.  Mr. Donaldson’s reports, the court also noted, indicate that, prior to the alleged work incident, the employee had problems getting and keeping work due to his personality difficulties.  In addition, we noted, although the employee had been seen by psychiatric personnel at HCMC and by Dr. Karayusuf and Dr. Pleasants, none of the reports of this treatment was included in the record.  Based on the record submitted at that time, the court concluded that the employee had not presented sufficient evidence of a substantial change in condition that was clearly not anticipated and could not reasonably have been anticipated at the time of the award.

The employee discontinued therapy with Mr. Donaldson and, in January 1993, was referred to licensed social worker Ted Harrison at Wauona Training and Consulting, Inc.  Mr. Harrison diagnosed post-traumatic stress disorder [PTSD] and chronic depression and began providing individual therapy to the employee at a frequency of about three times per month.

On October 31, 1997, the employee was seen for a psychiatric/psychological evaluation by Dr. Rodger Kollmorgen.  In a report to the employee’s attorney on December 6, 1997, Dr. Kollmorgen reported his opinion that the employee had suffered “for the past several years” from PTSD, with ongoing depression related to that disorder.  He opined that the employee’s PTSD was directly related to the incident of June 8, 1989, and was the substantial and overriding factor in the employee’s inability to return to work since the event occurred.  In addition, the doctor stated that the employee’s psychological condition had substantially deteriorated following his 1989 settlement.  In Dr. Kollmorgen’s opinion, the employee had been rendered totally disabled from gainful employment due to his deteriorating psychological injuries and condition since June 27, 1989.  And he rated the employee’s permanent partial disability as a result of the work-related assault at 30% of the whole body.

On October 25, 2004, Mr. Harrison wrote to the employee’s attorney and stated that, although the employee’s condition had greatly improved with therapy and medications, “[his] present condition and primary diagnosis of Depression still constitute a substantial change in his psychological condition and his ability to return to gainful employment as compared with his condition at [the] time of the settlement.”  In follow-up letters to Mr. Johnston on March 1, 2007, and August 26, 2008, Mr. Harrison reported that his opinions regarding the employee’s condition and therapy had remained unchanged.  He stated also, however, that there had been little progress in the employee’s therapy since 2004.

On May 19, 2009, the employee again petitioned this court to vacate the 1989 award.  The employee contends again that there has been a substantial change in his medical condition since the time of settlement and now also that the award on stipulation was based on a mutual mistake of material fact.  In an affidavit accompanying his petition, the employee asserts that neither PTSD nor major depression had been diagnosed at the time of the settlement.  Even after years of therapy, he contends, his medical condition is still markedly worse than it was in October of 1989.  He contends that, as a result of the psychological injuries that he suffered as a result of his work-related assault, he has never been able to return to work.  In addition to records he submitted to this court in 1992, the employee has included records from HCMC, Dr. Alford Karayusuf, Dr. F.S. Abuzzahab, The Minneapolis Clinic of Neurology, Ltd., Dr. Rodger Kollmorgen, Britton Center, P.A., and Wauona Training and Consulting, Inc.  The employer and insurer filed an objection to the petition to vacate, alleging that principles of res judicata bar the employee from re-litigating issues decided at the time of the prior petition to vacate.

This court may set aside an award “for cause” pursuant to Minnesota Statutes section 176.461.  For awards issued prior to July 1, 1992, cause for vacation includes substantial change in condition, with the inquiry limited to the extent of improvement or worsening of the injury; a change in condition need not have been unanticipated.  Franke v. Fabcon, Inc., 509 N.W.2d 373, 49 W.C.D. 520 (Minn. 1993).  Citing dictum in a decision by this court in Wilson v. Hallett Constr. Co., 45 W.C.D. 231 (W.C.C.A. 1991), the employer and insurer contend that, in order to prevail on a current petition, principles of res judicata require that an employee demonstrate further deterioration in his condition since any previous denial of vacation, which, they argue, the employee has not done in this case.  We disagree with the legal premise.

Principles of res judicata apply in workers’ compensation matters in some instances, but they do not bar further proceedings to determine claims not litigated in a prior proceeding.  See Westendorf v. Campbell Soup Co., 309 Minn. 550, 243 N.W.2d 157, 28 W.C.D. 460 (1976).  In the context of petitions to vacate, such unlitigated and so still viable claims are claims based on new evidence, not necessarily claims based on further change of condition since the previous denial.  The fact that this court determined that the employee had not presented sufficient evidence of a substantial change in condition in 1992 is not res judicata with regard to a subsequent petition brought in 2009 in which new evidence is presented.  Nor does that earlier decision change the court’s current analysis.  In Battle v. Gould in 1990, and in many cases since, this court has held that, in petitions based on a change in medical condition, we are simply to compare the employee’s conditionat the time of the petition with the employee’s condition at the time of settlement, see  Battle v. Gould, 42 W.C.D. 1085 (W.C.C.A. 1990); see also Franke at 367-77, 49 W.C.D. at 525; there is no requirement that we compare the condition at the time of the petition with the condition at the time of any previous petition.  Here, the employee is not seeking to relitigate the petition considered by this court in 1992.  He has brought a new petition, in which he has offered an abundance of records and reports that were not considered in 1992.  The employee has undergone considerable psychotherapy, counseling, and evaluation since 1992, the records of which have made the increased severity of his condition since the date of settlement - - if not since the date of the previous petition - - more evident.  He has also offered records from HCMC and Dr. Karayusuf that were not introduced in 1992.  The relevant inquiry for this court is a comparison of the employee’s condition at the time of the settlement in 1989 and his condition in 2009.  See Virnig v. Carley Foundry, Inc., slip op. (W.C.C.A. Nov. 14, 2000).

This court has delineated the following factors for consideration in determining whether an award should be vacated based on a substantial change in condition: (1) changes in the employee’s diagnosis; (2) changes in the employee’s ability to work; (3) the development of any additional permanent partial disability; (4) the necessity of more costly and extensive medical care or nursing services than was anticipated; and (5) the causal relationship between the work injury and the worsening of the condition.  Fodness v. Standard Cafe, 41 W.C.D. 1054 (W.C.C.A. 1989).

In the present case, it is apparent that the employee’s diagnosis has changed.  At the time of the award on stipulation, the last doctor to have seen the employee for his work injuries had indicated that the employee had recovered with no apparent physical sequelae.  Mr. Atherton, a social worker at HCMC whose report was probably not even considered by the parties at the time of settlement, had diagnosed only moderate depression with co-dependent personality characteristics.  The employee has subsequently been diagnosed with PTSD and chronic depression, and he continues with that dual diagnosis at the present time.  We conclude that the employee has established a change in his diagnosis since the time of the award.

The employee also contends that there has been a change in his ability to work.  At the time of settlement, the employee was alleging entitlement to only one week of temporary total disability benefits.  No treating medical provider had assigned any restrictions or recommended that he refrain from working.  Since the award and presently, multiple mental health professionals have opined that the employee is unable to work.  In addition, the employee has been receiving Social Security disability benefits since December 1989.  Although he was not working at the time of settlement, we conclude that the employee has established a change in his ability to work since October of 1989.

Mr. Donaldson and Dr. Kollmorgen have opined that the employee’s psychological conditions warrant a 30% impairment rating under Minnesota Rules 5223.0060, subpart 8.E.(2), of the permanent partial disability schedules.  The employee’s now-claimed psychological conditions were neither diagnosed nor rated at the time of settlement.  The employee has adequately established a change in permanent partial disability for purposes of the current petition.

The employee contends that, at the time of settlement, the doctors at HCMC had stated that he had fully recovered from his physical injuries.  Since that time, however, he has treated consistently and extensively with a variety of mental health professionals.  The costs related to his evaluations and treatment have been paid by medical assistance.  We conclude that the employee has demonstrated the necessity of more costly and extensive medical treatment than was anticipated at the time of settlement.

The employee’s treating doctors and therapists, including Mr. Donaldson, Mr. Harrison, Dr. Pleasants, Dr. Abuzzahab, and Dr. Kollmorgan, have all related the employee’s diagnosed psychological conditions to his assault at work on June 8, 1989.  Although the employee has yet to establish that the assault arose out of and in the course of his employment, we find that he has adequately satisfied the causation requirements for purposes of vacating his 1989 award on stipulation.

Because the employee has adequately demonstrated a change in diagnosis, a change in his ability to work, increased permanent partial disability, and a need for more extensive medical care than was initially anticipated at the time of settlement, and because the relationship between his psychological conditions and the incident of June 8, 1989, is supported by the employee’s petition, we find good cause to vacate the 1989 award on stipulation.  This decision should not be construed, however, as an opinion as to the employee’s entitlement to benefits.  The employee must establish his entitlement to additional workers’ compensation benefits at a subsequent hearing.  In view of our determination of a substantial change in condition, we will not address the alternate, mutual mistake, grounds for vacation argued by the employee.