Comparing Reconstructive Grafts under Confounding by Indication

Abstract

Graft choice in observational surgery studies reflects clinical judgment, prior treatment, anatomy, availability, and patient goals. Those same factors can influence outcomes, complicating comparisons that attribute an observed difference to the graft. This conceptual methods article develops a design for comparative graft research using superior capsular reconstruction and revision ACL reconstruction as separate applications. It specifies eligibility, treatment versions, time zero, follow-up, and outcomes before choosing an adjustment method. Propensity scores and matching are considered as ways to address measured baseline differences, with explicit attention to overlap and remaining bias. The framework distinguishes a material effect from the effect of a complete operative strategy and separates precision from identification. No cohort is newly analyzed and no comparative effect is estimated. The contribution is a practical causal-design specification for studies motivated by graft biology and revision-management evidence.