The employee seeks to vacate and set aside an Award on Stipulation, served and filed April 19, 2002, based upon a substantial change in medical condition not anticipated at the time of the settlement, mutual mistake and newly discovered evidence.  We conclude the employee’s petition to vacate the award is premature, and dismiss the petition without prejudice.

On April 30, 2001, Theresa L. Enstad, the employee, worked for Granite Falls Municipal Hospital, the employer, then self-insured for workers’ compensation liability with claims administered by Berkley Risk Administrators.  On that date, the employee contends she sustained a personal injury of which the employer had statutory notice.  The employer and insurer denied liability for the employee’s claim.

Following her injury, the employee received chiropractic treatment and in June 2001 began treating at Affiliated Medical Centers.  A cervical MRI scan showed a disc protrusion at C5-6 and a disc protrusion at C6-7 with a small spur.  A CT myelogram in July 2001 showed a broad-based disc protrusion at C5-6.  Dr. Maxwell, the neurosurgeon who ordered the scans, stated the MRI scan and CT myelogram were unremarkable, and concluded the employee had no anatomical defect amenable to surgery.  Another cervical MRI scan in February 2002 was essentially unchanged and an MRI scan of the lumbar spine was normal.  Cervical discography in March 2002 indicated four levels of the cervical spine were significantly painful with concordant pain.

The employee filed a claim petition in September 2001 alleging she sustained a personal injury to her neck, upper back and low back and seeking wage loss and permanent partial disability benefits and payment of medical expenses.  The parties entered into a settlement in March 2002 in which the employee settled all claims against the self-insured employer on a full, final and complete basis, including future medical expenses, in exchange for payment of $13,000.00.  An Award on Stipulation was served and filed on April 19, 2002.

In December 2002, the employee began working for Renville County Hospital.  In May 2003, the employee had a flare up of neck pain with radiation into her right arm.  An EMG in June 2003 was normal.  A repeat MRI scan of the cervical spine showed bulging of the C5-6 disc and a ridge of bone at C6-7.  In August 2003, Dr. Larkins performed an anterior cervical fusion at C5-6 and C6-7.  Following physical therapy, the employee returned to work in November 2003, with restrictions.

On November 28, 2004, the employee contends she sustained a personal injury arising out of and in the course of her employment with Renville County Hospital.  The employee saw Dr. Kramer on November 29, 2004, complaining of an increase in low back pain.  A cervical CT scan in February 2005, showed the bone graft incorporated with some disc space at C6-7.  A lumbar MRI scan on the same date showed degenerative disc disease and disc bulging at L4-5.  An MRI scan of the cervical spine showed no change since the July 2, 2004, scan.  In March 2005, the employee saw Dr. Garvey at the Twin Cities Spine Center.  A cervical discogram was ordered which showed 0/10 pain at C4-5 and 2/10 non-concordant pain at C7-T1.  A lumbar CT scan showed 3-level degenerative disc disease.  A lumbar discogram showed 2/10 concordant pain at L3-4, 8/10 concordant pain at L4-5 and 1/10 non-concordant pain at L5-S1.  Dr. Garvey then performed a posterior spinal fusion with plate and cable fixation from C5 to C7 in April 2005.  In September 2005, the employee underwent anterior spinal fusion with instrumentation at L4-5, posterior decompression at L4-5 with a fusion and fixation.

The employee filed a claim petition in August 2005, contending she injured her neck and back on November 28, 2004, and seeking wage loss benefits, permanent partial disability benefits and medical expenses.  Renville County Hospital and its insurer denied the employee sustained a personal injury and denied liability for benefits.  On February 23, 2006, the employee filed a petition to vacate the prior 2002 Award on Stipulation.  The self-insured employer objects.

Normally, in a case involving a petition to vacate, this court would review the facts to determine whether the employee has established good cause to vacate the award under Minn. Stat. §§ 176.461 and 176.521, subp. 3.  Here, however, the respondents contend the employee’s petition is premature as she currently has litigation pending before the Office of Administrative Hearings based upon a claimed November 28, 2004, injury while working for Renville County Hospital.  In support of this position the respondents cite the cases of Kinnunen v. BrockwayGlass, slip op.  (W.C.C.A. Jan. 27, 2000) and Pendzimas v. Northstar Drilling, slip op. (W.C.C.A. Mar. 29, 2001).

Where an employee has entered into a stipulation for settlement with one employer and insurer and later sustains a new work-related injury with a different employer and insurer, the second employer and insurer are liable for full payment of the benefits due the employee.  Johnson v. Tech Group, Inc., 491 N.W.2d 287, 47 W.C.D. 367 (Minn. 1992); Webeck v. Mochinski General Contractors, 41 W.C.D. 1063 (W.C.C.A. 1989).  It is not necessary to establish the second injury is the sole cause of the employee’s current disability only that it is a substantial contributing cause.  See Salmon v. Wheelabrator Frye, 409 N.W.2d 495, 40 W.C.D. 117 (Minn. 1987).  Thus, if the employee successfully establishes that the alleged November 28, 2004, injury is a substantial contributing factor to her current disability, she will be entitled to full recovery from Renville County Hospital.  It is, therefore, unnecessary and premature to vacate the April 19, 2002, Award on Stipulation.  If a compensation judge finds the employee did not sustain a new injury in 2004 while employed by Renville County Hospital, or that the 2004 injury is not a substantial contributing cause of the employee’s current disability, the employee may file a new petition to vacate.  We, accordingly, dismiss the employee’s petition to vacate award on stipulation, without prejudice.