Rotational stability of a posterior stabilized total knee arthroplasty.
The effect of the posterior stabilizing mechanism on rotational stability in total knee arthroplasty (TKA) was investigated in six cadaver knees using a special knee-testing device. The device evaluated varus-valgus, rotational, and anteroposterior (AP) stability in the normal knee compared to a posterior stabilized TKA with either a rotationally constrained or an unconstrained articular surface. None of the stability parameters was significantly different from normal in either configuration of the tibial surface, but the constrained surface did decrease rotational deflection compared to the rotationally unconstrained surfaces. These findings show that rotational constraint in a posterior stabilized TKA is not necessary to achieve rotational stability as long as varus-valgus stability is achieved by appropriately tensioning the collateral ligaments.
Whiteside
L A
LA
DePaul Biomechanical Lab, Bridgeton, Missouri.
Amador
D D
DD
D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D007720:Knee Prosthesis; D009068:Movement; D011474:Prosthesis Design; D012399:Rotation