Short-keeled cemented tibial components show an increased risk for aseptic loosening.
BACKGROUND
The choice of implant design plays an important role for primary fixation of a TKA. Short-keeled tibial components allow implantation through a smaller approach with less femorotibial subluxation.


OBJECTIVE
The purpose of this study was to detect early implant failure resulting from aseptic loosening after cemented short-keeled and standard tibial baseplate implantation.


METHODS
Between 2008 and 2010, a group of 160 consecutive patients (with 80 standard and with 80 short-keeled tibial trays) received cemented TKAs. At 1-year followup, patients were examined clinically and radiographs were analyzed regarding aspects of radiolucency. The components were divided into five zones on each radiographic view and the measurements of the 10 zones were added.


RESULTS
The mean sum of radiolucencies was increased significantly with the short-keeled baseplates. In the current study, short-keeled tibial trays revealed a revision rate of 6.3% after 1-year followup. In contrast, none of the standard tibial baseplates were revised.


CONCLUSIONS
The implantation of cemented, short-keeled tibial components is linked to an increased rate of early loosening. Therefore, the indication for cemented, short-keeled component implantation should be reviewed.


METHODS
Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Department of Joint Replacement Surgery, ARCUS Kliniken Pforzheim, Pforzheim, Germany.
Christian
C
Ries
Markus
M
Heinichen
Florian
F
Dietrich
Eike
E
Jakubowitz
Christian
C
Sobau
Christian
C
Heisel
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects / Q000295:instrumentation*; D001843:Bone Cements / Q000009:adverse effects / Q000627:therapeutic use*; D002484:Cementation / Q000009:adverse effects; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery*; D013997:Time Factors; D017211:Treatment Failure
D001843:Bone Cements