[Bone remodeling around cementless tantalum cups].
OBJECTIVE
Most studies have reported a significant decrease in periacetabular bone stock one year after implantation of a cementless cup. The purpose of this work was to study the bone-implant interface of the tantalum cup using plain X-rays and dual-energy X-ray absorptiometry (DEXA).


METHODS
This retrospective analysis concerned 42 patients with a tantalum cup, Trabecular Metaltrade mark (Zimmer, Warsaw, IN, USA). All hips had primary implantations, performed by one surgeon via the same approach and with the same postoperative rehabilitation protocol. Minimum follow-up was two years. The Harris clinical score, and radiographic (lucent lines and acetabular position) and densitometric (analysis of 3.3mm of periacetabular bone in the three DeLee and Charnley zones) were recorded.


RESULTS
At follow-up, the mean Harris score was 81. There were no implant malpositions (horizontal, vertical, inclination). Lucent lines were noted for 14% of the cups. Bone mineral density (BMD) was higher than generally observed with cementless cups (1.290+/-0.309g/cm(2)).


CONCLUSIONS
The clinical and radiographic results are similar to data in the literature regarding correct implant position. The higher rate of lucent lines around the tantalum cup is also reported in the literature and is the result of the pressfit, resolving at one year. The greater BMD in zone 1 might reflect better force transfer to the weight-bearing zone.


CONCLUSIONS
As biomaterial recently introduced in orthopedic surgery, tantalum appears to provide a better force transfer to the central part of the iliac bone and thus possibly better preservation of pelvic bone stock.
Grillo
J-C
JC
Service de Chirurgie Orthopédique et de Traumatologie, Hôpital Sainte-Marguerite, Marseille, France. jgrillo@voila.fr
Flecher
X
X
Bouvenot
J
J
Argenson
J-N
JN
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016723:Bone Remodeling; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D012189:Retrospective Studies; D013635:Tantalum
D013635:Tantalum