The employer and insurer petition to vacate the December 16, 1994, decision of Compensation Judge Danny Kelly, on the grounds that the employee is no longer permanently and totally disabled as a result of her work injury.  Finding no basis to vacate, we deny the petition.

The employee sustained a Gillette^[1] and specific injury to her low back on March 4, 1981, while working for Environment for Learning [the employer] as a teacher intern.  Dr. H. William Park diagnosed a probable herniated disc at the L5-S1 level, and the employee was adjudicated to have a 15% disability of the back.^[2]  In a Findings and Order filed December 16, 1994, Compensation Judge Danny Kelly found that the employee suffered from chronic pain syndrome as a result of the work injury, that the work injury was a substantial contributing cause of the employee’s continuing chronic depression, and that the employee had been permanently totally disabled since the date of injury.  The employer and insurer appealed from this decision, which was eventually affirmed by the Workers’ Compensation Court of Appeals and the Minnesota Supreme Court.

On September 25, 1996, the employee filed a claim petition, claiming benefits for an additional 5% permanent partial disability of the back, alleging that permanent total disability benefits had been underpaid, and seeking payment of outstanding medical expenses.  The parties entered into a stipulation for settlement in December of 1998, pursuant to which the employee was paid $33,500.00 to close out claims for an additional 5% permanent partial disability of the back, 20% permanent partial disability of the whole body for a psychological or psychiatric condition, 15% simultaneous injury factor, underpayment of permanent total disability benefits, out-of-pocket medical expenses, interest, and penalties.  An Award on Stipulation was filed on December 17, 1996.

After the issuance of Judge Kelly’s 1994 Findings and Order, the employee continued to treat with psychiatrist Dr. Eduardo Colon at the University of Minnesota and, later, Hennepin County Medical Center [HCMC].^[3]  He has diagnosed the employee as suffering from recurrent major depression, chronic post-traumatic stress disorder, and chronic pain syndrome.  In a report dated April 14, 2006, he noted that the employee has had psychiatric hospitalizations at the University of Minnesota and HCMC but has avoided psychiatric hospitalizations for the last five years.  It was Dr. Colon’s opinion that the employee’s chronic pain, including her back pain, is a substantial contributing cause of her disability and depression.

The employee has treated intermittently with psychologist Dr. Norman Cohen since 1988.  He diagnosed the employee with post-traumatic stress disorder related to a botched breast surgery in 1976.  He also diagnosed major depression.  In April of 2006, he re-evaluated the employee after having not treated her for a period of three years.  In his report dated April 28, 2006, Dr. Cohen noted that the employee’s chronic pain had been a topic of discussion during every appointment over the years.  He opined that the disc herniation and resulting chronic pain from the March 1981 work injury were still a substantial contributing cause of the employee’s permanent total disability.

Dr. Nolan Segal conducted independent medical examinations of the employee on June 30, 2004, and January 30, 2006.  He opined that there had been inconsistencies in the employee’s reporting of the alleged work injury, that the employee exhibited signs of symptom magnification and pain behaviors, that there was no objective evidence of lumbar radiculopathy on exam, and that video surveillance showed the employee walking with no visible discomfort.  He concluded that the 1981 work injury was not a substantial contributing cause of the employee’s musculoskeletal condition and that the employee was not permanently totally disabled.

The employee was evaluated by psychiatrist Dr. Thomas Gratzer in January of 2006, for an independent psychiatric evaluation.  Dr. Gratzer diagnosed major depressive disorder, anxiety disorder, post-traumatic stress disorder, and “rule out pain disorder associated with psychological factors.”  While he concluded that the employee was disabled from employment as a result of her psychiatric condition, he opined that the 1981 work injury “was one of many stressors and is not a proximal cause to Ms. Cassidy’s current major depressive illness.”^[4]

On March 10, 2006, the employer and insurer filed a petition to vacate Judge Kelly’s 1994 Findings and Order on the basis of a substantial change in condition.  The employee objected.

The employer and insurer’s petition to vacate is governed by Minn. Stat. § 176.461.  Under that statute, cause to vacate includes “a substantial change in medical condition since the time of the award that was clearly not anticipated and could not reasonably have been anticipated at the time of the award.”  Id.

The employer and insurer contend that there has been a substantial change in the employee’s medical condition, in that surgery for the employee’s lumbar disc herniation is no longer under consideration, no neurological deficits were found on examination by Dr. Segal on January 30, 2006, Dr. Segal has opined that the employee is not permanently totally disabled from a musculoskeletal standpoint, and the employee takes “no more than Extra Strength Tylenol for her back pain.”  Based on these contentions, the employer and insurer argue that the employee’s back condition has resolved or improved to a degree not anticipated by Judge Kelly’s 1994 Findings and Order.  We are not convinced.

An MRI of the employee’s lumbar spine was performed on June 23, 2004, and showed advanced L4-5 disc degeneration and narrowing with mild dorsal bulging that flattens the thecal sac.  There was also multilevel lumbar disc degeneration from L1-2 through L5-S1.

The employee was seen at Medical Pain Clinic on April 21, 2006, with a chief complaint of low back pain.  A physical examination was conducted by Dr. Thomas G. Cohn, who also reviewed an MRI performed on January 27, 2006.^[5]  Dr. Cohn diagnosed lumbar radiculopathy and discogenic pain syndrome involving one or more lumbar discs, and he opined that the MRI study correlated with the employee’s pain complaints.  He ordered a therapeutic lumbar epidural steroid injection and referred the employee to physical therapy for evaluation and treatment. A TENS unit was also ordered.

Dr. Robert A. Wengler examined the employee on May 10, 2006, and, in a report of that date, he stated that his neurological exam of the employee revealed a slight depression of the employee’s right ankle reflex, and straight leg raising was “acutely” positive at 20 degrees.  His assessment was that the employee had discogenic back pain with right lower extremity sciatica, and he opined that the employee is permanently totally disabled and may be a candidate for a decompression.

In his 2004 report, Dr. Segal stated that “I find no evidence to actually substantiate a significant work-related back injury occurring in March 1981," and he pointed to inconsistencies in histories contained in the medical records from the time of the injury.  He also referenced radiographic studies from 1987 and 1991 when opining, “I cannot therefore ascribe any of her lumbar spine, thoracic spine, or cervical spine abnormalities to the March 4, 1981 injury.”  These records, however, predated the 1994 decision of Judge Kelly, wherein he found that the employee had sustained a 15% permanent partial disability of the back and was permanently totally disabled as a result of the 1981 work injury.  Similarly, in his 2006 report, Dr. Segal opined that the employee had reached MMI from her 1981 work injury in June of 1981 and that she did not have any permanent impairment associated with that injury.  It has, however, been adjudicated that the employee sustained a significant work injury occurring in March of 1981 and that that work injury was permanent in nature.  Nothing in Dr. Segal’s reports can be interpreted as showing a substantial improvement in the employee’s physical condition since the issuance of the 1994 Findings and Order.  Rather, Dr. Segal apparently does not believe that the employee ever sustained a significant injury resulting in any permanency.  As such, we find Dr. Segal’s opinions insufficient to justify vacation of Judge Kelly’s decision.

The employer and insurer contend that the employee’s 1981 work injury is no longer a substantial contributing cause of the employee’s mental health condition.  In this regard, they rely on the opinion of Dr. Gratzer indicating that the employee’s mental health condition is consistent with a severe chronic major mental illness, a chemical imbalance not associated with psychosocial stressors or external factors.  We are not persuaded.
On the one hand, Dr. Gratzer opined that the 1981 work injury was “one of many stressors but not a proximal cause to Ms. Cassidy’s current major depressive illness.”  His opinion to this effect was based on Dr. Segal’s report that there are no ongoing physical stresses related to the 1981 injury and the fact that there have been a series of psychological stressors, separate from the 1981 injury, that are more temporally correlated to the employee’s current psychiatric condition.  On the other hand, Dr. Gratzer opined that the employee has developed a severe major mental illness, “chronic, refractory major depression,” which is a biological disorder “resulting from a chemical imbalance and is not the result of external stressors or factors.”  These theories, however, were substantially discredited by both Dr. Colon and Dr. Cohen.

In his April 14, 2006, report, Dr. Colon specifically addressed Dr. Gratzer’s theories but opined that “major depression is generally acknowledged to be significantly increased in the context of chronic pain.”  In addition, Dr. Colon specifically opined that the employee’s chronic pain “including her back pain” is a substantial contributing cause of her disability and depression.

Dr. Cohen also addressed Dr. Gratzer’s theories in his April 28, 2006, report.  While he acknowledged that genetic or biochemical factors may contribute to depression, Dr. Cohen cited professional sources indicating that stressful life events, or psychosocial factors, may also contribute.  Dr. Cohen went on to state specifically that the employee’s low back herniation and chronic pain still substantially contribute to the employee’s psychiatric disability.

We are not convinced that the employee’s long-term depression somehow went from being related to the 1981 work injury, as found in the 1994 Findings and Order, to being related solely to other psychosocial stresses or a chemical imbalance.  The psychiatric/psychological records from 1994 to the present reflect that the employee’s symptoms have waxed and waned and that she has at times been suicidal and at times has functioned better.  However, a constant in those records has been the continuing reference to her chronic pain, which her treating doctor, psychiatrist, and psychologist have related to her 1981 work injury.  And, because even Dr. Gratzer agrees that the employee is disabled from employment due to her psychiatric condition, there is no basis upon which to find that the employee is no longer permanently totally disabled.^[6]

We find no basis to conclude that there has been a substantial change in the employee’s psychiatric condition since the issuance of the 1994 Findings and Order.  The employer and insurer’s petition to vacate is therefore denied.