title: Anteroposterior Knee Stability During Stair Descent.
abstract: This study examined the influence of tibio-femoral conformity on anteroposterior (AP) knee stability during stair descent, particularly with a dished cruciate sacrificing (CS) design. A joint simulator simulated stair descent of cadaveric knees. Tibio-femoral displacement was measured. Knees were tested in intact, ACL-deficient, and TKA with cruciate-retaining (CR), CS and posterior-stabilizing (PS) inserts. Loading during stair descent simulation caused femur displacement anteriorly prior to quadriceps contraction. Quadriceps contraction reestablished the initial femoral AP position. During simulated stair descent, AP stability was restored using PS, CR or CS inserts with an intact PCL. The CS design without the PCL did not provide AP stability. Increasing quadriceps force to restore AP stability may explain the clinical findings of pain and fatigue experienced by some patients after TKA.
authors: Baylor College of Medicine, Houston, Texas.
authors: Kyle A
authors: KA
authors: Borque
authors: The Institute of Orthopedic Research Education, Houston, Texas.
authors: Jonathan E
authors: JE
authors: Gold
authors: Houston Methodist Hospital, Houston, Texas.
authors: Stephen J
authors: SJ
authors: Incavo
authors: Houston Methodist Hospital, Houston, Texas.
authors: Rupal M
authors: RM
authors: Patel
authors: The Institute of Orthopedic Research Education, Houston, Texas.
authors: Sabir E
authors: SE
authors: Ismaily
authors: Baylor College of Medicine, Houston, Texas; The Institute of Orthopedic Research Education, Houston, Texas.
authors: Philip C
authors: PC
authors: Noble
mesh_terms: D000368:Aged; D016118:Anterior Cruciate Ligament / Q000601:surgery; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D001696:Biomechanical Phenomena; D004867:Equipment Design; D005260:Female; D005269:Femur / Q000601:surgery; D006801:Humans; D007719:Knee Joint / Q000502:physiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000601:surgery; D016119:Posterior Cruciate Ligament / Q000601:surgery*; D052097:Quadriceps Muscle / Q000502:physiology / Q000601:surgery; D013977:Tibia / Q000601:surgery
keywords: anteroposterior knee stability; cruciate-retaining inserts; cruciate-sacrificing inserts; posterior-stabilizing tibial inserts; total knee arthroplasty