[¶ 1.] Randy Kasuske (Kasuske) petitioned the South Dakota Department of Labor (Department) to reopen his workers’ compensation claim. After a hearing, the Department issued an order dismissing Kasuske’s petition. On appeal, the circuit court affirmed the Department’s decision. Kasuske appeals. We affirm.
FACTS
[¶ 2.] Randy Kasuske was employed as a shipping clerk by Farwell, Ozmun, Kirk & Co. (Employer). In March 1983, Ka-suske injured his lower back while lifting a seventy-five pound box. Kasuske felt pain in his lower back that extended down his left leg.
[¶ 3.] It was later discovered that Ka-suske had suffered a herniated disk. Over the course of several years, Kasuske underwent multiple surgeries performed by multiple physicians. Employer, through its insurer, Great American Insurance Companies (Insurer), paid the expenses associated with Kasuske’s surgeries, physical therapy, pain medications, and other workers’ compensation benefits. Kasuske stopped working in 1987 and began receiving social security disability benefits in 1988. He later filed a petition for hearing with the Department, alleging that the injury had rendered him permanently and totally ..disabled.
[¶ 4.] In 1992, Kasuske entered into a settlement agreement with Employer and Insurer. He released Employer and Insurer from all .past, present, and future claims, including his claims for permanent and total disability benefits under the odd lot doctrine. In exchange, Employer and Insurer paid Kasuske a lump sum of $60,000, plus an additional $1,795.18 in unpaid medical expenses. The agreement permitted Kasuske to pursue future medical treatment. However, Employer and Insurer reserved the right to dispute whether the treatment was reasonable, necessary, or medically related to Ka-suske’s injury. The Department approved the agreement and dismissed Kasuske’s petition with prejudice.
[¶ 5.] Kasuske’s physical condition did not change during the four years subsequent to signing the agreement. However, in 1996, he started complaining of pain in his upper back, shoulders, arms, and hands. He also complained of extreme headaches. Kasuske sought treatment for these ailments from several physicians.
[¶ 6.] He petitioned the Department to reopen his claim based upon the claim that his condition had deteriorated by developing new and more serious features. Employer responded by arguing that Kasuske had already been compensated for his permanent and total disability and that the agreement barred him from collecting further benefits. Both parties filed motions for summary judgment on whether the settlement agreement barred Kasuske’s petition to reopen. The Department denied Employer’s motion and granted summary judgment for Kasuske, relying on our decision in
Sopko v. C & R Transfer Co., Inc.,
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[¶ 7.] Kasuske and his wife were the only witnesses who testified at the hearing. He introduced his medical evidence by stipulation. In addition, he introduced various letters between his attorney and his physicians. Employer introduced the deposition of its expert witness, Dr. Farn-ham, who had conducted an independent medical examination of Kasuske.
[¶ 8.] The Department concluded that Kasuske’s present condition was not causally related to the injury he sustained in 1983 and, as a result, ruled in favor of Employer. Kasuske appealed to the circuit court. The circuit court affirmed, relying on the same rationale as the Department. We address the following issue on appeal:
Whether Kasuske met his burden of proving that his present medical conditions are causally related to the 1983 injury. 1
Standard of Review
[¶ 9.] “In workers’ compensation cases, our standard of review is controlled by SDCL 1-26-37.”
Kassube v. Dakota Logging,
[¶ 10.] Finally, pure questions of law and mixed questions of law and fact are fully reviewable.
Enger,
Decision
[¶ 11.] “Ordinarily, workers’ compensation awards whether by agreement or adjudication are final unless the Department reserves jurisdiction.”
Sopko,
Any payment, including medical payments under § 62-4-1, and disability payments under § 62-4-3 if the earnings have substantially changed since the date of injury, made or to be made *455 under this title may be reviewed by the Department of Labor pursuant to § 62-7-12 at the written request of the employer or of the employee and on such review payments may-be ended, diminished, increased, or awarded subject to the maximum or minimum amounts provided for in this title, if the department finds that a change in the condition-of the employee warrants such action[]
(emphasis added).
[12.]The party asserting a “change in condition” bears the burden of proving it.
2
Sopko,
The “change in condition” which justifies reopening and modification is ordinarily a change, for better or worse in claimant’s physical condition. This change may take such forms as progression, .deterioration, or aggravation of the com-pensable condition, achievement of disabling character by a previously symptomatic complaint, appearance of new and more serious features, such as discovery of a disc herniation in a back case, failure to recover within the time originally predicted, and superimposition or .worsening of a neurotic condition.
[13.]It is also well settled that “to recover. disability benefits under the workers’] compensation statutes, the claimant has the burden of establishing a causal connection between the employment and the disability.”
Day v. John Morrell Co.,
[14.] Our modern cases have not focused on the causation element of reopening a workers’ compensation claim.
Mills
focused only on the effect of the release and settlement and whether the
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claimant had proved a “change in condition.”
Mills,
[15.] We addressed, in a collateral manner, the issue of causation in
Sopko.
[16.]Kasuske relies heavily on this portion of
Sopko,
claiming that we are limited to the settlement agreement in determining the issue of causation. However, as Employer points out in its brief, Kasuske’s argument fails in two respects. First, the parol evidence upon which the employer relied in
Sopko
was testimony by the claimant’s attorney that he could not have proved that the injury was causally related to the employment had the matter not been settled. Kasuske, on the other hand, urges us to ignore the medical records and vocational reports in the present case. Because a “change in condition” must be proved to reopen a workers’ compensation claim, this evidence will be highly relevant in all matters similar to the present case. Indeed, it would be very difficult to ascertain a “change in condition” if courts cannot examine the pre-settlement and post-settlement medical records. Second, even if we were to adopt Kasuske’s position, he would be precluded from relying on the parol evidence rule because he failed to object to any of this evidence at the hearing.
First Nat’l Bank v. Bank of Lemmon,
[17.]In summary, there are three things a claimant must prove to have his workers’ compensation claim reopened. First, the claimant must prove a “change in condition.” Second, the claimant must prove that the asserted “change in condition” derives from an injury unknown at the time of settlement or from a known injury with its disabling character unknown. Finally, a claimant must prove that the unknown injury is causally connected to employment, or that the unknown disabling character is causally connected to the original, compensable injury.
[18.]Kasuske claims his “change in condition” includes additional pain in his arms, upper back, and shoulders. He also claims that he suffers constant headaches. According to Kasuske, this additional pain is the result of myofascial pain syndrome 3 which is turning into fibromyalgia. 4 After reviewing the record, we conclude that Kasuske has failed to meet his burden of proving his alleged “change in condition” is causally connected to his original, compen-sable injury.
[19.] The record in this case is comprised of thousands of pages of medical records and correspondence. Kasuske has been treated by four different physicians since
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entering into the settlement agreement with Employer. Two of those physicians now support his assertion that his new conditions are causally related to the injury he suffered in 1983. However, those physicians have been inconsistent in their opinions. The other two treating physicians concluded that either Kasuske does not have fibromyalgia, or that it is impossible to determine the cause of fibromyalgia. Finally, a fifth physician, who conducted an independent medical examination of Ka-suske, determined that he did not have fibromyalgia and, that even if he did, it would not be related to the injury suffered in 1983. This was the only physician whose testimony was subject to cross-examination. The other four physicians’ opinions were introduced by affidavit, or by way of medical records that were stipulated to between the parties. We cannot say it was error for the Department to rely more heavily upon the deposition testimony.
See Paulson v. Black Hills Packing Co.,
[20.]Affirined.
Notes
. Kasuske raises several issues on appeal. We find some without merit and others unnecessary to address because of our holding on the issue of causation.
. The Department did not reach the issue of whether Kasuske suffered a "change in condition.”
. "A condition characterized by chronic pain in the muscle tissues, similar to fibromyal-gia.” Available at http://www.med-terms.com/script/main/art. asp?ar-ticlekey=11694 (Last visited on 12/23/2005).
. "A syndrome characterized by chronic pain, stiffness, and tenderness of muscles, tendons, and joints without detectable inflammation.” Available at http://www.med-terms.com/script/main/art. asap?ar-ticlekey=3453 (Last visited on 12/23/2005).
. Because of our holding as to causation, it is unnecessary to address whether Kasuske's symptoms constitute a "change in condition.”