Background: While total knee arthroplasty (TKA) remains a highly successful intervention for end-stage knee osteoarthritis, patient dissatisfaction rates consistently hover around 20%. To address this, surgeons have increasingly transitioned from uniform mechanical reconstruction to personalized, patient-specific alignment strategies. This paper reviews the underlying principles, technical execution, and clinical evidence of emerging alignment paradigms.

Methods: A comprehensive literature synthesis was conducted utilizing the PubMed database to evaluate mechanical, anatomical, kinematic, inverse kinematic, restricted kinematic, and functional alignment techniques in primary TKA.

Results: Traditional mechanical alignment (0 ± 3 degrees relative to the mechanical axis) prioritizes implant longevity, though its strict superiority regarding survivorship remains debated. Conversely, personalized techniques—such as kinematic alignment (KA) and functional alignment (FA)—prioritize physiological soft-tissue tension and constitutional anatomy. Short-term randomized controlled trials demonstrate comparable or superior patient-reported outcome measures (PROMs) with personalized strategies. However, concerns persist regarding outlier wear and early tibial component loosening in extreme varus configurations.