Schleiss v. SAIF Corp., 317 P.3d 244

Claimant (Schleiss) injured his low back at work in April 2008; SAIF accepted a lumbar strain and closed the claim after an evaluating physician found no significant MRI abnormalities and no PPD award.
Claimant sought reconsideration and a medical arbiter; the arbiter found moderate impairment and apportioned 33% to the work injury and 67% to preexisting mild degenerative changes and smoking-related accelerated aging.
The Appellate Review Unit (ARU) and then the Workers’ Compensation Board (WCB) awarded 5% whole-person PPD after apportioning impairment under OAR 436-035-0013(1) to exclude the portion not "due to" the compensable injury.
Claimant challenged the rule-based apportionment as inconsistent with ORS 656.214, arguing that "due to" means "caused in material part by," so the compensable contribution entitles him to the full impairment rating unless a statutory combined-condition apportionment applies.
The Court of Appeals affirmed the Board; the Oregon Supreme Court granted review to decide whether OAR 436-035-0013 is consistent with the statutes governing PPD and combined conditions.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether OAR 436-035-0013(1) permissibly allows apportionment of PPD awards to exclude impairment not "due to" the compensable injury	"Due to" means "caused in material part by"—if compensable injury materially contributed, all impairment is compensable unless a statutory combined-condition apportionment applies	Rule reasonably implements statutes by apportioning the percentage of total impairment attributable to non-compensable causes; claimant could have pursued a combined-condition claim if appropriate	The rule conflicts with ORS 656.214 as applied here because the non‑work causes the Board relied on were not legally cognizable preexisting conditions; all claimant's impairment was "due to" the compensable injury for purposes of ORS 656.214

Barrett v. D & H Drywall, 300 Or 325 (holding impairment triggered by a compensable injury that makes a preexisting asymptomatic condition symptomatic may be compensable)
Barrett v. D & H Drywall (on reconsideration), 300 Or 553 (clarifying that compensable injury triggering symptoms can make resulting impairment "due to" the compensable injury)
Olson v. State Ind. Acc. Com., 222 Or 407 (defining "arising out of" as work being a material contributing cause)
Smothers v. Gresham Transfer Inc., 332 Or 83 (discussing major contributing cause standard for consequential and combined conditions)
State v. Gaines, 346 Or 160 (statutory construction methodology)
Hopkins v. SAIF, 349 Or 348 (defining "arthritis"/"arthritic condition" and evidentiary requirements for preexisting arthritic conditions)