Arthroplasty in the Valgus Knee: Comparison and Discussion of Lateral vs Medial Parapatellar Approaches and Implant Selection.

Constrained implants are frequently used for primary total knee arthroplasty (TKA) in patients with moderate and severe genu-valgum (>10˚). This deformity presents corrective challenges for ligament release. The lateral-parapatellar approach has been advocated as an alternative to the traditional medial-parapatellar approach.