Armstrong v. Longview Farm, LLP, 938 N.W.2d 425

Claimant Alan Armstrong had long‑standing, severe bilateral knee osteoarthritis documented years before 2016 and had been a candidate for total knee replacement for over a decade.
Armstrong sustained a work injury at Longview Farm on March 31, 2016; MRI showed severe degenerative changes but no major acute structural injury.
Longview’s insurer (Travelers) denied that the 2016 injury was a "major contributing cause" of Armstrong’s need for knee replacement and stopped medical payments; Armstrong nonetheless underwent bilateral total knee replacements in May 2016.
The left knee developed a postoperative infection requiring additional surgeries; Armstrong seeks coverage for the knee replacement and post‑surgical care under workers’ compensation.
Administrative Law Judge (ALJ) credited the independent medical examiner (Dr. Bissell) over claimant’s treating surgeon (Dr. Adler), concluding the degenerative osteoarthritis—not the 2016 work injury—remained the primary cause of Armstrong’s need for replacement.
The Department and the circuit court affirmed denial of compensability; Armstrong appealed to the South Dakota Supreme Court, which affirmed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
1. Admissibility—leading question to Dr. Bissell	Objection: ALJ erred by allowing a leading redirect question that elicited critical testimony.	Question only restated prior testimony; admission within ALJ discretion and not prejudicial.	No abuse of discretion; even if leading, no shown prejudice.
2. Causation under SDCL 62‑1‑1(7)(b) (preexisting non‑work disease)	March 31 injury was the tipping point and thus remained a major contributing cause of need for surgery.	Medical evidence shows severe, progressive osteoarthritis long predating the injury; work event did not remain a major contributing cause.	Affirmed: claimant failed to prove the injury ‘‘remained a major contributing cause.’’
3. Causation under SDCL 62‑1‑1(7)(c) (preexisting compensable work injury)	2005 work injury plus 2016 event together support coverage under last‑injurious‑exposure rule.	2005 care did not establish a compensable ongoing condition tied to work; record lacks medical proof that 2016 event independently aggravated a prior compensable injury.	(c) inapplicable or not proven; claimant failed to show independent contribution.
4. Coverage for post‑surgical care	Post‑op care is compensable if surgery is compensable.	Because surgery is not compensable, related post‑surgical care is not compensable.	Not reached on merits because surgery denied; post‑surgical care thereby not compensable.

Jewett v. Real Tuff, Inc., 800 N.W.2d 345 (S.D. 2011) (proof must show work injury remained a major contributing cause; causation requires reasonable medical probability)
Martz v. Hills Materials, 857 N.W.2d 413 (S.D. 2014) (review of findings based on documentary medical evidence is de novo)
Byrum v. Dakota Wellness Foundation, 654 N.W.2d 215 (S.D. 2002) (distinguishes SDCL 62‑1‑1(7)(b) and (c) based on whether preexisting condition was occupational)
Arends v. Dacotah Cement, 645 N.W.2d 583 (S.D. 2002) (adoption of last‑injurious‑exposure rule for successive workplace injuries)
Grauel v. S.D. Sch. of Mines & Tech., 619 N.W.2d 260 (S.D. 2000) (medical evidence insufficient when degenerative arthritis, not the incident, explains need for replacement)
Vollmer v. Wal‑Mart Store, Inc., 729 N.W.2d 377 (S.D. 2007) (documentary evidence standard and de novo review of such findings)