Preoperative Planning for Primary Total Knee Arthroplasty (Mechanical, Anatomic, and Kinematic Alignment)

In primary total knee arthroplasty (TKA), proper knee alignment and soft tissue integrity are key requirements for long-term outcomes and implant survival. Various alignment techniques—mechanical, anatomical, kinematic, and hybrid—are discussed, each with specific indications and benefits. Preoperative clinical and radiological assessments are crucial, evaluating parameters such as ligamentous laxity, flexion contractures, deformity reducibility, and range of motion (ROM). Radiographic examinations are helpful to determine the alignment and structural details needed for planning. Mechanical alignment aims for neutral limb alignment, while anatomical and kinematic alignments focus on preserving natural knee kinematics. Digital planning, increasingly using 3D modeling, enhances surgical precision and efficiency, predicting implant size and positioning more accurately.