This JAAOS review surveys the competing philosophies and technologies for achieving alignment and soft-tissue balance in TKA. It addresses the mechanical vs. kinematic alignment debate, compares measured resection to gap balancing, and critically evaluates patient-specific instrumentation, computer navigation, inertial systems, and pressure sensors — asking which approaches have evidence to back their claims.
When planning TKA in a patient with pre-existing femoral deformity or a prior intramedullary implant, computer-assisted or inertial navigation allows accurate alignment without canal instrumentation — a genuine indication for these technologies.
When evaluating a post-TKA patient with medial-sided pain or early loosening, check tibial component varus: even 3° of varus tibial positioning is associated with increased medial tibial bone failure and accelerated polyethylene wear.
This JAAOS review surveys the competing philosophies and technologies for achieving alignment and soft-tissue balance in TKA. It addresses the mechanical vs. kinematic alignment debate, compares measured resection to gap balancing, and critically evaluates patient-specific instrumentation, computer navigation, inertial systems, and pressure sensors — asking which approaches have evidence to back their claims.
When planning TKA in a patient with pre-existing femoral deformity or a prior intramedullary implant, computer-assisted or inertial navigation allows accurate alignment without canal instrumentation — a genuine indication for these technologies.
When evaluating a post-TKA patient with medial-sided pain or early loosening, check tibial component varus: even 3° of varus tibial positioning is associated with increased medial tibial bone failure and accelerated polyethylene wear.