Nontraumatic tibial polyethylene insert cone fracture in mobile-bearing posterior-stabilized total knee arthroplasty.
A 72-year-old male patient underwent mobile-bearing posterior-stabilized total knee arthroplasty for osteoarthritis. He experienced a nontraumatic polyethylene tibial insert cone fracture 27 months after surgery. Scanning electron microscopy of the fracture surface of the tibial insert cone suggested progress of ductile breaking from the posterior toward the anterior of the cone due to repeated longitudinal bending stress, leading to fatigue breaking at the anterior side of the cone, followed by the tibial insert cone fracture at the anterior side of the cone, resulting in fracture at the base of the cone. This analysis shows the risk of tibial insert cone fracture due to longitudinal stress in mobile-bearing posterior-stabilized total knee arthroplasty in which an insert is designed to highly conform to the femoral component.
Department of Orthopedic Surgery, National Hospital Organization, Nara Medical Center, Nara, Japan.
Yohei
Y
Tanikake
Department of Orthopedic Surgery and Rehabilitation, Otemae Hospital, Chuo-ku, Osaka, Japan.
Koji
K
Hayashi
Department of Orthopedic Surgery, Nara Medical University, Kashihara, Nara, Japan.
Munehiro
M
Ogawa
Department of Orthopedic Surgery, Nara Medical University, Kashihara, Nara, Japan.
Yusuke
Y
Inagaki
Department of Arthroplasty and Regenerative Medicine, Nara Medical University, Kashihara, Nara, Japan.
Kenji
K
Kawate
Department of Orthopedic Biomaterial Science, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
Tetsuya
T
Tomita
Department of Orthopedic Surgery, Nara Medical University, Kashihara, Nara, Japan.
Yasuhito
Y
Tanaka
Mobile-bearing; Nontraumatic; Polyethylene cone fracture