Abstract
Valgus accounts for 18.5% of patients undergoing a total knee arthroplasty (TKA). Following a mechanical alignment (MA) surgical technique, these patients have historically been more challenging than their varus counterparts. In valgus knees, conventional MA-TKA frequently distalizes and posteriorizes the lateral femoral condyle, increasing lateral patellar retinaculum tension and flexion space imbalance and instability. Personalized arthroplasty is gaining popularity for varus knees, but its value remains debated for valgus knees. This reluctance stems from outdated misconceptions about valgus knee anatomy and biomechanics and limited awareness of advancements in implant survivorship and outcomes. Patients with valgus HKA may present with various knee laxities. While medial collateral ligament (MCL) pseudo-laxity and generalized hyperlaxity are easy to manage, true MCL elongation requires careful evaluation and may necessitate surgical modifications. A surgical approach favoring patellar tracking and avoiding increasing medial compartment gaps is of paramount importance. Joint laxity assessment should guide surgical decisions, from tibial undercutting for mild laxity to soft tissue releases or constrained implants for severe instability. In the presence of a pathological patellofemoral joint, the surgical technique should be adapted with trochlear position/orientation modifications, patellar resurfacing medializing the implant, lateral retinacular release, or a tibial tuberosity osteotomy. Long-term studies show high patient satisfaction with restricted kinematic alignment, TKA in valgus knees, with outcomes comparable to varus knees.