On January 15, 2020, the South Dakota Supreme Court issued an opinion in Armstrong v. Longview Farms, LLP, 2020 S.D. 1, that differentiates between the effects of an acute injury and the effects of a non-work-related degenerative condition in assessing causation. This is a significant decision that signals a more nuanced approach to causation, challenging the “cause-in-fact” arguments often asserted in workers’ compensation claims.
On March 31, 2016, Armstrong injured his left knee while working for Longview Farms, a pork producer. Armstrong was scraping the floor of Longview Farms’ hog confinement building with a curved push blade when the blade caught on the floor, causing Armstrong to fall on his left leg.
Armstrong had previously sustained two other work injuries with different employers. In 1999, Armstrong was irrigating cotton when his left knee suddenly “clicked” and became painful. He underwent surgery to repair a torn meniscus. In 2005, Armstrong slipped and fell onto his left knee at work. During arthroscopic surgery addressing Armstrong’s 2005 injury, the surgeon discovered the presence of severe osteoarthritis. Armstrong discussed the possibility of undergoing a total knee replacement, but instead chose to pursue conservative treatment. At several points after his 2005 work injury, Armstrong complained of worsening knee pain. Over the years, Armstrong told his providers that he knew he needed knee replacement surgery but wanted to wait.
After Armstrong’s 2016 injury, he chose to proceed with a total left knee replacement surgery. Travelers, Longview Farms’ workers’ compensation insurer at the time, denied coverage for the surgery, asserting that Armstrong’s 2016 work injury was not a “major contributing cause” of Armstrong’s left knee condition. An independent medical evaluation was previously conducted of Armstrong and found that the 2016 work injury was not a major contributing cause of Armstrong’s knee condition. The treating provider for Armstrong disagreed, citing the basis for his opinion being that Armstrong was able to do heavy work before the injury, but was not able to work after the injury.
At the administrative hearing, the Department found the testimony of the independent medical examiner more persuasive. The Department acknowledged that Armstrong’s 2016 work injury contributed to his disability but was not a major contributing cause. The circuit court affirmed, and Armstrong then appealed to the South Dakota Supreme Court challenging, in part, causation.
The Supreme Court discussed South Dakota’s causation standard, set out in SDCL 62-1-1(7)(b), and that it requires a work injury be a major contributing cause of a claimant’s current condition and need for treatment to be compensable. In Armstrong, the South Dakota Supreme Court found no evidence in the record that Claimant’s osteoarthritis was related to his employment at Longview Farms, noting that for a long period of time before Armstrong’s 2016 injury, his medical providers commented on the need for knee replacement surgery. In reaching this conclusion, the South Dakota Supreme Court rejected Dr. Adler’s argument that “relegated the causation standard of SDCL 62-1-1(7)(b) to an elementary cause-in-fact determination.” Armstrong, 2020 S.D. 1, citing Jewett, 2011 S.D. 33, ¶ 24. The Supreme Court further noted a lack medical testimony linking Armstrong’s osteoarthritis to his work injury.
The South Dakota Supreme Court looked deeper than the treating provider’s analysis, parsing out the totality of Armstrong’s disability, and separated the effects of Armstrong’s acute incident from the effects of his pre-existing osteoarthritis. This decision rejects the cause-in-fact arguments that are often asserted in cases where an acute incident overlays a non-work-related preexisting condition and more closely examines the contributions of acute injury and pre-existing conditions to a claimant’s overall condition and need for treatment.