[Reflexions about unicompartmental knee arthroplasty]

UKA should remain a resurfacing prosthesis. Peripheral and central ligaments have to be intact.Bone (re)sections transform the aim of this arthroplasty in a pejorative way.Operative indication is specific.UKA cannot modify the global mechanical axis of the lower limb. Hypocorrection must remain the rule.The thickness of the prosthesis helps to establish ligamentous equilibrium in flexion and extension.The use of a metal back tibial component, in our view, is not necessary in this type of arthroplasty. Polyethylene tibial component must be at least 6 mm thick.Methylmethacrylate has not been shown to be inferior.Neither phlebitis nor postoperative physiotherapy should be underestimated in this type of arthroplasty.