The employee petitions to vacate a stipulation for settlement approved in an award issued March 19, 2004.  Finding that the employee has established cause pursuant to the statute, we grant the petition.

Matthew Klennert sustained a work injury to his low back on December 1, 2001, while he was working for SNG Construction.  He was carrying a box of siding weighing in excess of 100 pounds when he twisted his back and sustained a low back injury. Mr. Klennert was 35 years old on the date of injury, had a high school education, no further vocational training, and a work history primarily limited to home remodeling.

Initially, Mr. Klennert sought chiropractic care for treatment of his injury.  Records from the chiropractic clinic show there were in excess of 20 visits and the employee’s complaints were of low back pain and bilateral leg pain with numbness.  Mr. Klennert was then referred to Noran Neurological Clinic where he saw Dr. Gerald Morley.

The employee first saw Dr. Morley on December 28, 2001, and advised him that his pain was 8 out of 10 and radiated from his low back down into both legs.  Dr. Morley authorized an MRI that was read as showing disc herniations at L5-S1 and L4-5 with some displacement of the right S1 nerve.  The employee was treated with medication, but told Dr. Morley he received no significant relief from his pain.

At the request of the employer and insurer, the employee was seen for an independent medical examination by Dr. Bruce Mack on June 18, 2002.  Dr. Mack diagnosed the employee’s work injury as “lumbar disc herniation at L5-S1, producing right nerve root irritation.”  No treatment recommendations were made, and Dr. Mack believed Mr. Klennert could work on a light-duty basis, lifting up to 25 pounds occasionally with increasing hours.

The employee saw Dr. Charles Burton at the Institute for Low Back and Neck Care on June 21, 2002.  Dr. Burton diagnosed, “a large contained disc herniation extending into the foraminal zone at L5-S1 on the right.”  Dr. Burton recommended surgical decompression and if there was found to be segmental dysfunction at L5-S1, “limited local stabilization would be attempted.”  Some question of the viability of this approach was noted because the employee was a smoker.

The employee had his surgery on September 12, 2002.  In a subsequent chart note, Dr. Burton described the procedure as “multi-level decompression and strut flexible stabilization arthrodesis.”  On October 23, 2002, Dr. Burton stated the employee was doing well and had “made excellent progress since his surgery.”  Mr. Klennert was referred to a low back rehabilitation program for therapy.  In February 2003, he was released to work on a moderate basis, lifting up to 30 pounds frequently. A functional capacities evaluation (FCE) was done at Sister Kenny Institute in May 2003.  The conclusion of the FCE was that Mr. Klennert could work at a light-work level, defined as lifting up to 20 pounds with frequent lifting up to 10 pounds.

Dr. Burton found the employee to be at maximum medical improvement when he saw him on September 15, 2003, and told Mr. Klennert that no follow-up appointment was needed.  Dr. Burton also rated the employee as having 13 percent permanent partial disability under Minn R. 5223.0390, subp. 4.E. and subp. 4.E.(3).  This rating was paid by the employer and insurer.

In January 2004, Mr. Klennert returned to Dr. Burton reporting that he had had the return of left leg pain.  Dr. Burton stated that, “in all probability Mr. Klennert has had a recurrent disc herniation.”  An MRI was recommended.  In a letter to Mr. Klennert dated February 5, 2004, advising him that the MRI did not show a recurrent herniation, Dr. Burton stated, “If you can remain a non-smoker and maintain a daily health maintenance program using your LTX, there is a reasonable chance that you may get by without the need for additional surgery.”

The employee saw Dr. Burton again on March 8, 2004, and reported that “he is on a daily health maintenance program using an LTX.  He is, however, still taking Percocet, Oxycontin, and Wellbutrin.”  Dr. Burton referred the employee to a chronic pain management program and ended his chart note by stating, “Unless the patient develops significant neurologic problems in the future and becomes a surgical candidate, there is no need for him to return for evaluation.”

The parties entered into a settlement of the employee’s claim arising out of his December 2001 work injury in March 2004.  The stipulation stated the employee’s claim was for ongoing temporary partial disability.  The response of the employer and insurer in the stipulation was that the employee was capable of earning his pre-injury wage.  The employer and insurer agreed to pay $35,000 to the employee, including attorney fees, in return for a full, final, and complete waiver of all claims except for non-chiropractic medical expenses.  An award on stipulation was issued on March 19, 2004.

Mr. Klennert filed an application for Social Security Disability Insurance benefits (SSDI) on December 6, 2002.  After the initial denial of his claim, a request for a hearing was filed in May 2003 and a hearing was held on March 12, 2004, before an administrative law judge of the Social Security Administration.  The medical expert at the hearing testified that Mr. Klennert’s medical condition met the requirements for a finding of disability under Social Security regulations and the administrative law judge awarded benefits as of December 1, 2001, in a decision that was issued May 27, 2004.

On June 11, 2004, Mr. Klennert saw Steven Lawson, the physician’s assistant for Dr. Thomas Rieser at Midwest Spine and Orthopaedics, with “symptoms of low back pain, equal bilateral hip/buttock pain, and equal posterior pain to the feet.”  An assessment was made of pseudoarthrosis after a review was done of radiographic studies, and a discogram was recommended.  The discogram showed disc disruption at L4-5 and L5-S1 levels, and Mr. Klennert saw Dr. Rieser for further evaluation.  Dr. Rieser recommended anterior/posterior fusion surgery at L4-5 and L5-S1.  Dr. Rieser performed the surgery on September 30, 2004.

Mr. Klennert was evaluated by Dr. Paul Wicklund on behalf of the employer and insurer on May 16, 2005.  Dr. Wicklund described the 2002 surgery as “an attempt to do a limited stabilization procedure using what Dr. Burton described as a dorsilateral flexible bone stabilization arthrodesis.  This technique never led to fusion at either L4-5 or L5-S1, but because the decompression was successful, the patient got some relief of pain.”  Dr. Wicklund concluded that the surgery done by Dr. Rieser was reasonable and necessary and “[t]he reason he needed the fusion was because when Dr. Burton did the bilateral decompression and removal of facet joints the spine became more unstable and the original fusion Dr. Burton did, did not heal.”

The employee continued to treat with Dr. Rieser, whose records indicated a solid fusion after the surgery with a reduction of pain in his low back and legs.  According to the records submitted by the employee to this court, the last time the employee saw Dr. Rieser was September 18, 2009, at which time he had no pain and was “basically doing great.”

Dr. Rieser prepared a medical report of April 27, 2012.  Dr. Rieser concluded that there had been a change in diagnosis and provided a rating of permanent partial disability of 20 percent for the employee’s low back condition.

The employee has now petitioned this court to vacate the award on stipulation served and filed March 19, 2004.  The employee alleges good cause, as defined by Minn. Stat. § 176.461, exists in that there has been a mutual mistake of fact and/or a substantial change in medical condition.  The employer and insurer have objected to the petition.

This court has authority to set aside an award for cause, defined in the statute as a mutual mistake of fact, newly discovered evidence, fraud, or a substantial change in medical condition since the time of award that was clearly not anticipated.  Minn. Stat. § 176.461.

We consider first the issue whether there was a mutual mistake of fact by the parties at the time of the settlement.  “A mutual mistake of fact occurs when opposing parties to the stipulation both misapprehend some fact material to their intended settlement of a claim or claims.”  Shelton v. Schwans Sales Enters., 53 W.C.D. 110, 113 (W.C.C.A. 1995).

The mutual mistake of fact asserted by the employee is the parties’ error as to the employee’s medical condition at the time of settlement.  Specifically, the employee argues, at the time of the settlement, the parties understood that the surgery done by Dr. Burton in 2002 had been successful, that the employee would not need further surgery, and that the employee was capable of full-time employment at a light-work level.  In fact, however, the employee’s 2002 surgery had not stabilized the employee’s spine, additional surgery was necessary, and the employee’s ability to be employed is problematic at best, since despite Dr. Rieser’s assessment, the employee is on SSDI.  In response, the employer and insurer contend that there is no evidence that they believed the employee was capable of employment.  Accordingly, they contend there was no mutuality and the employee’s argument must fail.

We note at the outset that our review is of the information available to the parties at the time of the stipulation and not information that was developed or produced after that time.  Franke v. Fabcon, 509 N.W.2d 373, 377, 49 W.C.D. 520, 525 (Minn. 1993).  We also note that the present case is not one of competing medical opinions.  The employer and insurer had no IME before the settlement except for Dr. Mack, who saw the employee in June 2002, before the surgery.  The only information on the employee’s medical condition at the time of settlement is that developed by Dr. Burton.

Dr. Burton’s records can only be read as stating that the employee’s surgery had been successful and that no further surgery or treatment would be necessary.  It is also apparent from the records and reports of Dr. Rieser and Dr. Wicklund that this surgery had not been successful, and Dr. Burton’s assessment of the employee’s status was incorrect.

As to employability, the employer and insurer argue that even at the time of settlement, the employee’s ability to work was doubtful and cite to the employee’s application for SSDI.  However, the award of SSDI was not made until after the settlement and at the time of the settlement, the pertinent information on employability was the FCE in May 2003.  That FCE stated that the employee was capable of work requiring lifting up to 30 pounds.  Further, on this issue, we note the stipulation stated the employee’s claim was one for temporary partial disability; there was no assertion that the employee was permanently totally disabled.  The amount of the settlement is not reflective of a settlement which contemplated a claim for permanent total disability.

We conclude then that there was a mistake at the time of the settlement.  It was a mistake of a material fact, not of law.  Fieck v. Brandrup & Assocs., slip op. (W.C.C.A. Oct. 6, 2004); Olin v. Tower Asphalt, Inc., slip op. (W.C.C.A. Feb. 5, 2002).  It was a mistake made by both parties and not just one of the parties.  Slaight v. Exceptional Homes, 70 W.C.D. 78 (W.C.C.A. 2010); Leach v. Ulland Bros. Inc., 70 W.C.D. 307 (W.C.C.A. 2010).  And we conclude it was a mistake that was material to claims being assessed by the parties at the time of the settlement.

In considering this matter, we also consider the Supreme Court’s decision in Monson v. White Bear Mitsubishi, 663 N.W.2d 534, 539, 63 W.C.D. 337, 344 (Minn. 2003).  In Monson, the employee had two surgeries for his low back injury, including a two-level fusion with instrumentation, and he settled his workers’ compensation claim on a full, final, and complete basis.  Medical records at the time of the settlement indicated a solid fusion, even though the employee continued to have low back pain.  After the settlement, Mr. Monson had increased pain and new radiographic studies showed there had been no fusion.

Monson petitioned to vacate the settlement on the basis of a mutual mistake of fact, substantial change in medical condition, or newly discovered evidence.  This court denied the petition, concluding that criteria for setting aside an award under those categories had not been met under case law developed by this court.

On appeal, the Minnesota Supreme Court reversed the Workers’ Compensation Court of Appeals, holding that the denial of the petition had been an abuse of discretion.  The court stated, “The development of new facts about the injury after the award, or even the subsequent discovery of facts and evidence but unknown at the time the award was made, is sufficient to justify the vacation of an award” and added,  “A mistake in diagnosis or extent of disability may also serve as grounds for reopening.”  Finally, we note the court’s admonition that “the system endeavors fairly and fully to compensate the meritorious injury claim.  Consequently, the Workers’ Compensation Act ‘permits adjustment of the award in relation to facts subsequently appearing so as to assure a compensation proportionate to the degree and duration of instability.’”  663 N.W.2d at 539, 63 W.C.D. 342, quoting Franke v. Fabcon, 509 N.W.2d 373, 376, 49 W.C.D. 520, 524 (Minn. 1993).

A review of the medical records demonstrates that the employee’s diagnosis was not what the parties had assumed it to be.  The consequences of that misapprehension are yet to be fully developed, but we conclude that a mutual mistake has been established by the employee.  Given this conclusion, we will not address the issue of whether there has been an unanticipated substantial change in medical condition.

The petition of the employee is granted.