Early femoral component loosening in DF-80 total hip arthroplasty.
Forty-seven DF-80 total hip arthroplasties performed in 40 patients were evaluated to determine the incidence and causes of early femoral component loosening. With an average 37.1-month follow-up period, 48.9% of the femoral components developed bone cement-bone radiolucent lines worrisome for stem loosening. Twenty-three percent of the stems had subsided and 4.3% had been revised. Radiolucent lines were apparent very early (average, 8.8 months). Statistical analysis revealed positive correlations between the use of the larger (45-mm) offset stem and both the appearance of radiolucent lines and stem loosening. Being male and tall also were associated with stem loosening. The causes for early DF-80 femoral component loosening could not be defined with certainty. The results of this study and a review of the literature suggest that failure may be a result of early biologic weakening of the proximal cement-bone interface combined with a stem design that maintains proximal bone loading. Metal debris did not appear to be a factor in loosening of this titanium alloy stem.
Robinson
R P
RP
Section of Orthopedics, Virginia Mason Medical Center, Seattle, Washington.
Lovell
T P
TP
Green
T M
TM
Bailey
G A
GA
D000368:Aged; D000497:Alloys; D001843:Bone Cements; D005260:Female; D005269:Femur; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D011474:Prosthesis Design; D011475:Prosthesis Failure; D013997:Time Factors; D014025:Titanium
D000497:Alloys; D001843:Bone Cements; C031462:titanium alloy (TiAl6V4); D014025:Titanium