TEN YEARS OF EXPERIENCE WITH CERAMIC-CERAMIC BEARING IN TOTAL HIP ARTHROPLASTY

Abstract

Since 1999 we have adopted the ceramic on ceramic bearing in total hip arthroplasty. We started with sandwich liners, abandoned afterwards in favor of all ceramic liners. We witnessed the progressive evolution of the diameters of the femoral heads from 28 mm to the actual 40 mm. Out of more than 500 implants, we experienced 1 case of fracture of the ceramics, 5 cases of squeaking and 5 dislocations. A total of 5 implants underwent revision.

Patients and Methods: In 1999 we started using a ceramic-ceramic bearing in THA with the SPH blind cup (Lima Lto, San Daniele del Friuli) that had a “sandwich” liner. The stem used was the F2L modular stem (Lima Lto.). In 2 years (1999–2000) we performed 32 total hip arthroplasties in 32 patients with these implants. From 2001 we started using an all-ceramic liner and two kind of stems: Modulus and C2 (Lima Lto). We performed from 2001 to 2003 76 total hip arthroplasties with these implants. From 1999 to 2003 the only diameter available for the heads was 28 mm. Starting from 2004, 32 and 36 mm heads were available. We implanted 391 ceramic-ceramic implants (23 28mm, 138 32mm and 230 36mm heads) using the Delta Cup (Lima Lto.). We’ve implanted 12 heads of 40 mm size. The stems used were the Modulus or the C2 stem.

We performed, from 1999, to March 2009 511 implants in 465 patients (46 bilateral). 320 patients were women, 145 men. Mean follow up is 5.3 years (6 months-10 years). Mean age was 68,4 years (18–80).

Results: The mean Harris Hip Score was 93,2 considering the overall population at last follow up (mean 5,3 years, range 6 months- 10 years). In 1 case we experienced the fracture of the liner. 5 implants had dislocations and 1 case needed revision. The other 4 implants were treated conservatively with excellent results at final follow up.

We had 5 cases of squeaking: in 1 case it recovered itself, in 2 cases the phenomenon is occasional and in 1 case it’s persistent. No revision surgery has been required by these 4 patients. 1 patient developed squeaking after a subdislocation and needed revision for substitution of the head.

We revised 3 other implants: 2 for infection and 1 for a periprosthetic fracture.

On the radiological side there were no signs of mobilization of the cup or of the stem.

We found radiolucent lines in 35 cases: 13 in zone 1 according to Gruen, 6 in zone 2 and 16 in zone 3. Radiolucent lines were always less than 2 mm wide and stable at all radiographic controls.

Discussion: The use of the ceramic-ceramic bearing in total hip replacement has become in the last years more and more widespread. This has been sustained by very strong data available in the literature about the results of these bearing surfaces at a long term follow up. Our experience shows excellent clinical and radiological results at a medium-long term follow up and are consistent with those published in the literature.