Long-term survival of the uncemented Balgrist total hip replacement cup

Abstract

Purpose The purpose of this study was to evaluate the longterm clinical and radiographic outcomes of the Balgrist total hip replacement cup. Methods We report the results of a retrospective review of 195 total hip prostheses with Balgrist cup implanted in 178 patients. There were 59 men and 119 women with a mean age at surgery of 52.3 years (range, 19-72). Cox regression was used to determine the influence of independent variables on the survivorship of the prosthesis. Results There were 117 (66 %) of 178 patients, and 131 (67 %) of 195 hips available for assessment at a mean follow-up of 17.4 years. A total of 21 patients (22 hips) were lost from follow-up (12 %). A total of 25 patients (27 hips) required some type of re-operation during the follow-up period. Eight of 27 re-operations (30 %) were directly caused by the Balgrist cup failure due to fatigue fracture of the metallic shell (n=5; 19 %), polyethylene wear (n=2; 7 %) and aseptic loosening (n=1; 4 %). The mean polyethylene wear rate was 0.068 mm/year (range, 0.008-0.230; SD=0.043). The risk of re-operation for any reason was decreased with dysplastic hip as a primary diagnosis (hazard ratio; HR=0.250; 95 % CI 0.086-0.725) and with greater age at the time of surgery (HR =0.923; 95 % CI 0.880-0.969). The 19-year survivorship with re-operation for any reason was 75.6 % (95 % CI 67.0-84.2). The 19-year survivorship with re-operation for the Balgrist cup failure was 90.5 % (95 % CI 83.4-97.6).Conclusions The Balgrist cup continues to provide excellent clinical and radiological outcomes. This is associated at least in part with a low polyethylene wear rate. The main reason for the Balgrist cup failure is fatigue fracture of the metallic shell.

Influence of trabecular bone quality and implantation direction on press‐fit mechanics

“…By eliminating impaction forces, Radial implantation might offer a more gentle insertion method and thereby reduce the risk of intraoperative damage to tissues in frail patients, and of component mal‐positioning . Radially expandable cups have already shown some clinical success . Radial implantation would require new designs, as well as patient‐specific pre‐operative planning.…”

“…Furthermore, cup orientation has been shown to be more variable for uncemented impaction than for cemented implantation (without impaction), suggesting that impaction could be related to mal‐positioning of implants . Radially expanding implants eliminate the necessity of impaction forces and have been used with some success to anchor acetabular shells . Such implants tend to employ sharp, macro‐scale, surface features that interdigitate with the bony bed, once the implant has been positioned and radially expanded.…”

“…[26][27][28] Radially expanding implants eliminate the necessity of impaction forces and have been used with some success to anchor acetabular shells. [29][30][31] Such implants tend to employ sharp, macro-scale, surface features that interdigitate with the bony bed, once the implant has been positioned and radially expanded. The use of radial expansion with standard micro-scale porous coatings might provide adequate stability in a design in which less radial expansion is necessary than that for a macroscale feature.…”

Characteristics of synovial fluid required for optimization of lubrication fluid for biotribological experiments

“…Patient characteristics, including gender, age, height, weight, body mass index (BMI), and joint localization are summarized in Table . The presence of aseptic loosening and/or osteolysis was confirmed/excluded using a standardized radiographic protocol in those who were not operated at the time of aspiration; in those who were operated, the radiographic findings were compared with intraoperative evaluation by a surgeon. In the case of discordance, the surgeon's view was superior and decisive for distribution into groups I or II.…”

System Analysis and Synthesis of Total Hip Joint Endoprosthesis

“…Constructions of endoprostheses and technologies of their implantation seen steady improvement with different viewpoints [11,41,42,44]. Thus have been developed and improved elements of endoprostheses, methods of their fixation, were used different materials and processing technologies of complex surfaces.…”