Results Best evidence analysis showed no difference in polyethylene wear rate , the frequency of cup migration , and aseptic loosening between monoblock and modular acetabular components .
No convincing evidence was found for the cl aim that lower frequencies of acetabular osteolysis are observed with the use of monoblock cups compared with modular uncemented cups .
Conclusions The purported benefits of monoblock cups were not substantiated by this systematic review of controlled studies in that polyethylene wear rates and frequencies of cup failure and acetabular osteolysis were similar to those observed with modular implants .
Background Monoblock acetabular components used in uncemented total hip arthroplasty ( THA ) have certain mechanical characteristics that potentially reduce acetabular osteolysis and polyethylene wear .
However , the degree to which they achieve this goal is not well documented .
Questions / purpose sThe purpose of this study was to use a systematic review of controlled trials to test the hypothesis that monoblock cups have superior ( 1 ) polyethylene wear rate ; ( 2 ) frequency of cup migration ; ( 3 ) frequency of acetabular osteolysis ; and ( 4 ) frequency of aseptic loosening compared with modular components used in uncemented THA .
Cementless coated and noncoated Mathys acetabular cups: radiographic and histologic evaluation.
This study evaluated 185 cementless Mathys coated and uncoated acetabular cups inserted for total hip replacement since September 1984 . All of the cups were high-density polyethylene .  Sixty were uncoated ( group A ) , 96 were coated with hydroxyapatite ( group B ) , and 29 were coated with titanium ( group C ) .  Cup survival was assessed clinical ly , histologically , and radiographically , and a computer-assisted EBRA method was used to evaluate cup migration . After a mean follow-up of 8 years , five cups in group A that had previously shown migration were revised as a result of aseptic loosening , while no loosening of hip sockets occurred in groups B and C. These results suggest that Mathys cups should be used only if coated with hydroxyapatite or titanium . Furthermore , the histologic evaluation in four cups from groups B and C revealed normal bone formation without inflammation or fibrotic tissue around the cups , promising long-term survival
Results Best evidence analysis showed no difference in polyethylene wear rate , the frequency of cup migration , and aseptic loosening between monoblock and modular acetabular components .
No convincing evidence was found for the cl aim that lower frequencies of acetabular osteolysis are observed with the use of monoblock cups compared with modular uncemented cups .
Conclusions The purported benefits of monoblock cups were not substantiated by this systematic review of controlled studies in that polyethylene wear rates and frequencies of cup failure and acetabular osteolysis were similar to those observed with modular implants .
Background Monoblock acetabular components used in uncemented total hip arthroplasty ( THA ) have certain mechanical characteristics that potentially reduce acetabular osteolysis and polyethylene wear .
However , the degree to which they achieve this goal is not well documented .
Questions / purpose sThe purpose of this study was to use a systematic review of controlled trials to test the hypothesis that monoblock cups have superior ( 1 ) polyethylene wear rate ; ( 2 ) frequency of cup migration ; ( 3 ) frequency of acetabular osteolysis ; and ( 4 ) frequency of aseptic loosening compared with modular components used in uncemented THA .