[Reconstruction by graft and reinforcement device in severe aseptic acetabular loosening: 10 years survivorship analysis].
OBJECTIVE
We report our experience with the treatment of aceptic acetabular loosening with important loss of bone stock using a graft and a metallic reinforcement device.


METHODS
We carried out a retrospective study on 56 acetabular revision arthroplasties with severe loss of bone stock performed between November 1980 and June 1992. Mean age of the 35 females and 19 males was 68.5 years. In all cases, there was a combined lesion (cavity + segmentary) of two roofs (type 3 or 4 in the SOFCOT classification). The superior wall was concerned in all cases (80 p. 100 with a combined lesion). Reconstruction was performed using grafts (autograft (n=15), allograft (n=39) or both (n=2)) covering more than 50 p. 100 of the socket. Structural grafts were embedded into the defects in case of superior combined lesion with extension to the anterior and the posterior walls. A morselized graft was used to fill other defects. The reinforcement device was a Müller ring (n=35) or the Burch-Schneider APC (n=21). Mean follow-up was 8.75 years (range 3 - 16 years).


RESULTS
There were 29 iterative aseptic loosenings of acetabular component revised or non-revised (n=11). Twenty-four of these cases had a Müller ring and 5 had a Burch-Schneider APC. The 10-year cumulative survival rate (CSR) was 0.43 +/- 0.16 and the 11-year CSR was 0.350.16 using iterative aseptic loosening as the end point. The lateral position of the hip center (p=0.02), female gender (p=0.03), and the Müller ring (p=0.0054) were statistically negative factors. The 10-year CSR was 0.44 +/- 0.18 for the Müller ring and 0.78 +/- 0.1 for the Burch-Schneider APC, the difference being statistically significant (p=0.007). These two populations were strictly comparable.


CONCLUSIONS
In case of important loss of bone stock, reconstruction by grafts is widely used as reported in the literature. A metallic reinforcement device must be used to protect the graft during incorporation and to prevent late resorption. Compared with the Müller ring, the Burch-Schneider APC is much more adapted to meet these requirements, particularly when the graft covers more than 50 p. 100 of the socket.
Bonnomet
F
F
Département d'Orthopédie et de Traumatologie, Hôpital Hautepierre, Hôpitaux Universitaires, avenue Molière, 67098 Strasbourg Cedex.
Clavert
P
P
Gicquel
P
P
Lefèbvre
Y
Y
Kempf
J F
JF
D000077:Acetabulum / Q000000981:diagnostic imaging / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D016025:Bone Transplantation / Q000379:methods*; D005260:Female; D006801:Humans; D016268:Internal Fixators; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D011859:Radiography; D012086:Reoperation / Q000295:instrumentation* / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome