Effect of Dorsal Acetabular Rim Loss on Stability of the Zurich Cementless Total Hip Acetabular Cup in Dogs

Abstract

Zurich Cementless acetabular cup stability does not appear to be compromised by 50% acetabular rim loss at normal physiologic weight bearing loads. Thus, for this system, modifying procedures such as augmentation of the dorsal acetabular rim or deeper reaming for acetabular bed preparation may not be necessary with up to 50% dorsal rim loss with the Zurich Cementless acetabular cup.

Deformation of the Zurich cementless acetabular cup caused by implantation in a canine cadaver model

“…The deformation was characterized as a cranial‐caudal pinching with concurrent dorsal‐ventral expansion of the cup, which reflects a pattern of distortion seen with some cup designs used in man . Our results also corroborate the belief that most of the press‐fit of the Zurich cup is generated between the cranial and caudal acetabular pillars …”

“…Each hemipelvis was securely fastened to a benchtop clamp and oriented to simulate a laterally recumbent position for surgery. The acetabulum was reamed with a 23‐mm reamer in a pivoting manner to a depth where the cranial and caudal acetabular bone columns would just cover the outer rim of the acetabular component by a board‐certified surgeon (SEK) in accordance with previously recommended guidelines . After acquiring DIC images of the cup in isolation (see below), the cup was impacted with a spherical impactor covered with a Teflon film.…”

Radiographic evaluation of early periprosthetic acetabular bone contrast and prosthetic head acetabular coverage after uncemented and cemented total hip prosthesis in dogs

“…Nevertheless, bone-remodeling measurements performed around uncemented THA remain more precise than those made around cemented THA [19]. The dorsal border of the acetabulum, including the weight-bearing portion of the acetabular rim [37], was not evaluated in the present study, since the dorsal acetabular edge is expected to be partially reamed during surgery, and most importantly superimposed by the prosthetic implants on extended VD projection [38]. However, future assessment of periprosthetic acetabular bone GV on both VD and mediolateral projections of coxofemoral joints is strongly recommended to support the findings reported in the present study.…”

Inter- and intra-observer variability of radiography and computed tomography for evaluation of Zurich cementless acetabular cup placement ex vivo

“…One of the most commonly reported complications following total hip arthroplasty is luxation, reportedly accounting for 1.1% to 8.5% of cases (1,2,5,7,8,11). Postoperative cup-related complications for total hip arthroplasty include coxofemoral luxation, cup avulsion, aseptic loosening, and periprosthetic acetabular fractures (5,12). Each of these complications require surgical revision and each can be caused by improper cup placement (5,12).…”

“…Postoperative cup-related complications for total hip arthroplasty include coxofemoral luxation, cup avulsion, aseptic loosening, and periprosthetic acetabular fractures (5,12). Each of these complications require surgical revision and each can be caused by improper cup placement (5,12).…”