Stability assessment of a moderately conforming all-polyethylene tibial component in total knee arthroplasty: a prospective RSA study with 2 years of follow-up of the Kinemax Plus design.
The magnitude and pattern of the migration of an all-polyethylene tibial component with moderately conforming articular surfaces in total knee arthroplasty was analyzed in 20 patients > or =60 years during a 2-year follow-up using radiostereometry (RSA). Most of the migration occurred during the initial 4 months, whereafter the migration diminished, reaching a mean maximum migration of 0.75 mm at 2 years. Similar patterns were found for rotation of the implant. Maximum subsidence at 2 years was 0.7 mm and was most commonly located at the posteromedial part of the tibial component. These results indicate that an all-polyethylene tibial component with moderately conforming articular geometry and with a thickness of 10-12 mm demonstrated migration patterns compatible with a favorable prognosis in regard to future aseptic loosening.
Adalberth
G
G
Department of Orthopedics, Uppsala University Hospital, Sweden.
Nilsson
K G
KG
Byström
S
S
Kolstad
K
K
Mallmin
H
H
Milbrink
J
J
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D011095:Polyethylenes; D011446:Prospective Studies; D011474:Prosthesis Design; D011475:Prosthesis Failure; D013977:Tibia
D011095:Polyethylenes