Ten-year results with the Morscher press-fit cup: an uncemented, non-modular, porous-coated cup inserted without screws Hydroxyapatite in Total Hip Arthroplasty: Clinical Results and Critical Issues Cross-linked Compared with Historical Polyethylene in THA: An 8-year Clinical Study Primary total hip arthroplasty with a cementless porous-coated anatomic total hip prosthesis: 10- to 12-year results of prospective and consecutive series. Primary Total Hip Arthroplasty with a Porous-Coated Acetabular Component. Seven-to-Ten-Year Results* Highly Crosslinked Polyethylene Does Not Reduce Aseptic Loosening in Cemented THA 10-year Findings of a Randomized Study Arthopor 2 acetabular component with screw fixation in primary hip arthroplasty: a 7- to 9-year follow-up study. Primary Total Hip Arthroplasty with a Second-Generation Cementless Total Hip Prosthesis in Patients Younger Than Fifty Years of Age The porous-coated anatomic total hip prosthesis, inserted without cement. A prospective study with a minimum of ten years of follow-up. Acetabular Polyethylene Wear and Acetabular Inclination and Femoral Offset Cementless Acetabular Replacement in the Young: A 5- to 10-Year Prospective Study A comparison of polyethylene wear rates between cemented and cementless cups. A prospective, randomised trial. Precoated femoral component in total hip arthroplasty. Results of 5- to 9-year followup. A Dual-mobility Cup Reduces Risk of Dislocation in Isolated Acetabular Revisions Effect of augmented cup fixation on stability, wear, and osteolysis: a 5-year follow-up of total hip arthroplasty with RSA. Ten-year survivorship of the Anatomique Benoist Girard I total hip arthroplasty. Matched-pair analysis of cemented and cementless acetabular reconstruction in primary total hip arthroplasty. Early experience with dual mobility acetabular systems featuring highly cross-linked polyethylene liners for primary hip arthroplasty in patients under fifty five years of age: an international multi-centre preliminary study Can Dual Mobility Cups prevent Dislocation in All Situations After Revision Total Hip Arthroplasty? No Increased Migration in Cups with Ceramic-on-Ceramic Bearing: An RSA Study Eight- to ten-year clinical and radiographic outcome of a porous tantalum monoblock acetabular component. The results of the titanium-coated RM acetabular component at 20 years: a long-term follow-up of an uncemented primary total hip replacement. Bioactive cement or ceramic/porous coating vs. conventional cement to obtain early stability of the acetabular cup. Randomised study of 96 hips followed with radiostereometry.
Total  hip arthroplasty ( THA )  with well design ed cementless acetabular implants has shown excellent results . The purpose of this study was to assess our clinical and radiological outcomes using an uncemented cup . We conducted a prospect i ve cohort study including all consecutive primary THAs performed with the Morscher press-fit cup , an uncemented non-modular acetabular component , between March 1996 and December 1998 . Patients were evaluated at ten years with clinical and radiological follow-up , patient satisfaction and question naire assessment using the Harris hip score ( HHS ) , Merle d’Aubigné and Postel score , the UCLA score , the 12-item short-form health survey ( SF-12 ) and a visual analog scale .  Five hundred sixty-one THAs were performed in 518 patients . At 120 months ( ± 7.3 months ) , 303 patients with 335 THAs were still available for follow-up . None of the patients had required cup revision for aseptic loosening . At ten years , the cup survivorship was 98.8 % ( 95 % CI 97.4–99.5 ) with cup revision for any cause as an endpoint . No radiolucencies were seen around the cups , but osteolytic defects involved 21 stems ( 8.3 % ) . Mean total linear polyethylene wear was 0.9 mm . The Morscher acetabular replacement cup provides excellent results at ten years . There were no revisions for aseptic loosening of the cup , and no osteolytic defects were found around the cup . Patient satisfaction was high and the clinical results were very good Surgeons who perform arthroplasties have posed some critical questions about hydroxyapatite . Does hydroxyapatite coating enhance bone ingrowth or ongrowth ? Will hydroxyapatite lead to increased polyethylene wear or an increased incidence of osteolysis ? Will the hydroxyapatite coating disappear , and if so , what will be left to maintain implant fixation ? A multicenter study of 316 hips ( 282 patients ) with a proximally hydroxyapatite coated stem and either a hydroxyapatite or porous coated cup were followed up 8.1 years ( range , 5.6 - 9.9 years ) . The average patient age was 50 years ( range , 16 - 81 years ) , and 61 % of the patients were male . One ( 0.3 % ) stem , three ( 2.7 % ) porous coated cups , and 25 ( 11.9 % ) hydroxyapatite coated cups were revised for aseptic loosening . Disappointing results on the acetabular side indicate that substrate design is critical . There were no cases of intramedullary femoral osteolysis , and the incidence of acetabular and proximal femoral osteolysis and polyethylene wear was no greater than that seen with other cementless or cemented components . Based on these clinical results and a critical review of the literature , it is concluded that hydroxyapatite coated hip components do enhance ingrowth or ongrowth with no increased incidence of osteolysis for as many as 10 years . Concern about the disappearance of the hydroxyapatite coating with time seems moot in light of the above clinical findings Abstract Wear particle-induced osteolysis is a major cause of aseptic loosening in THA . Increasing wear resistance of polyethylene ( PE ) occurs by increasing the cross-link density and early reports document low wear rates with such implants . To confirm longer-term reductions in wear we compared cross-linked polyethylene ( irradiation in nitrogen , annealing ) with historical polyethylene ( irradiation in air ) in a prospect i ve , r and omized clinical study involving 48 patients who underwent THAs with a minimum followup of 7 years ( mean , 8 years ; range , 7–9 years ) . The insert material was the only variable . The Harris hip score , radiographic signs of osteolysis , and polyethylene wear were recorded annually . Twenty-three historical and 17 moderately cross-linked polyethylene inserts were analyzed ( five patients died , three were lost to followup ) . At 8 years , the wear rate was lower for cross-linked polyethylene ( 0.088 ± 0.03 mm/year ) than for the historical polyethylene ( 0.142 ± 0.07 mm/year ) . This reduction ( 38 % ) did not diminish with time ( 33 % at 5 years ) . Acetabular cyst formation was less frequent ( 39 % versus 12 % ) , affected fewer DeLee and Charnley zones ( 17 % versus 4 % ) , and was less severe for the cross-linked polyethylene . The only revision was for an aseptically loose cup in the historical polyethylene group . Moderately cross-linked polyethylene maintained its wear advantage with time and produced less osteolysis , showing no signs of aging at mid-term followup . Level of Evidence : Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence We performed a prospect i ve study in 108 consecutive patients ( 116 hips ) who were followed for a minimum of 10 years ( 10 - 12 years ) after primary total hip arthroplasty using an uncemented porous-coated anatomic ( PCA ) hip prosthesis . The average age of the patients at operation was 48.4 years ( range , 19 - 85 years ) , and the diagnosis was avascular necrosis of the femoral head in 46 hips , neglected femoral neck fracture in 27 , osteoarthrosis secondary to childhood pyogenic arthritis in 24 , childhood tuberculous arthritis in 5 , and miscellaneous in 14 . The average preoperative Harris Hip Score was 55 points , which improved to 87 points at 11 years . Seventy-five hips ( 65 % ) were excellent , 11 ( 9 % ) were good , and 30 ( 39 % ) were poor . The overall rate of revision was 15 % ( 17 of 116 hips ) . The rate of revision of the femoral component was 11 % ( 13 of 116 hips ) , and the rate of revision of the acetabular component was 15 % ( 17 of 116 hips ) . The prevalence of thigh pain was 28 % at 11 years . The increase in the incidence of aseptic loosening of the femoral component was found to explain the high incidence of severe thigh pain at 11 years ' follow-up . At 11 years , there was femoral osteolysis in 69 hips ( 59 % ) and acetabular osteolysis in 65 hips ( 56 % ) . At 6 years , 20 hips ( 17 % ) showed definite wear of the polyethylene liner . At 11 years , 81 hips ( 70 % ) showed definite wear of the polyethylene liner . Because the complication rate of the PCA hip prosthesis with respect to loosening , osteolysis , and excessive wear in the polyethylene liner is high , we ab and oned the use of this implant One hundred and eighty-four patients who had been managed , between 1984 and 1985 , with a total of 204 consecutive primary total hip arthroplasties with insertion of a Harris-Galante type-I acetabular component without cement were prospect ively studied . There were eighty-two men ( 45 per cent ) and 102 women ( 55 per cent ) . The mean age at the time of the operation was fifty-two years ( range , twenty to eighty-four years ) . One hundred and fifty-seven patients ( 173 hips ) were available for clinical review at a mean of 104 months ( range , seventy-eight to 126 months ) . At this time , the mean preoperative Harris hip score of 52 points ( range , 12 to 79 points ) had improved to a mean of 90 points ( range , 44 to 100 points ) . Two patients ( two hips ) had had an exchange of an excessively worn polyethylene liner . One patient ( one hip ) had had débridement and grafting of an area of massive retroacetabular osteolysis . Two stable acetabular components ( 1 per cent ) had been revised at the time of femoral revision . None of the cups had been revised because of aseptic loosening . Radiographic examination of 150 patients ( 165 hips ) at a mean of 104 months ( range , seventy-eight to 126 months ) revealed that 156 cups ( 95 per cent ) were stable . Eight cups ( 5 per cent ) were considered to be possibly unstable , with a radiolucent line between the prosthesis and the bone that was one millimeter wide or less in at least four of five zones ; two of the eight had a complete radiolucent line in all zones . One component , which had been implanted with a bulk allograft from a femoral head , migrated more than two millimeters in the first two years and then stabilized without complication . Osteolysis was seen in seven acetabula ( 4 per cent ) and was limited to the periphery of the cup in six . Survivorship analysis at ten years revealed that the acetabular component had a 99 per cent chance of survival ( 95 per cent confidence interval , 0.98 to 1.0 ) with revision or aseptic loosening as the end point and a 97 per cent chance of survival ( 95 per cent confidence interval , 0.95 to 1.0 ) with revision , aseptic loosening , or reoperation because of a problem related to the acetabular component as the end point Background Polyethylene ( PE ) wear particles are believed to cause aseptic loosening and thereby impair function in hip arthroplasty .  Highly crosslinked polyethylene ( XLPE ) has low short- and medium-term wear rates . However , the long-term wear characteristics are unknown and it is unclear whether reduced wear particle burden improves function and survival of cemented hip arthroplasty . Questions / purpose sWe asked whether XLPE wear rates remain low up to 10 years and whether this leads to improved implant fixation , periprosthetic bone quality , and clinical function compared to conventional PE . Methods We r and omized 60 patients ( 61 hips ) to receive either PE or XLPE cemented cups combined with a cemented stem .  At 10 years postoperatively , 51 patients ( 52 hips ) were evaluated for polyethylene wear and component migration estimation by radiostereometry , for radiolucent lines , bone densitometry , and Harris hip and pain scores . Revisions were recorded . Results XLPE cups had a lower mean three-dimensional wear rate between 2 and 10 years compared to conventional PE hips : 0.005 mm/year versus 0.056 mm/year . We found no differences in cup migration , bone mineral density , radiolucencies , functional scores , and revision rate . There was a trend toward improved stem fixation in the XLPE group . The overall stem failure rate was comparably high , without influencing wear rate in XLPE hips . Conclusions XLPE displayed a low wear rate up to 10 years when used in cemented THA , but we found no clear benefits in any other parameters . Further research is needed to determine whether cemented THA design s with XLPE are less prone to stem loosening . Level of Evidence Level I , therapeutic study . See the Instructions for Authors for a complete description of levels of evidence The first 100 consecutive primary hip arthroplasties with the Arthopor 2 acetabular component ( Joint Medical Products , Stamford , CT ) with supplemental screw fixation performed by the senior author were prospect ively studied . The mean patient age was 57 years . Seventy-seven cemented and 23 cementless stems were placed , with 32-mm femoral heads used in most of the patients . Eighty-six hips were review ed at 7 - 8.8 years ( mean , 7.8 years ) . The mean Harris hip score at final follow-up evaluation was 94 points . No cups have been revised , although 2 cups in patients with radiation osteonecrosis were loose radiographically . One patient underwent revision of a severely worn liner . Despite a relatively high mean linear wear rate of 0.27 mm/y ( range , 0.13 - 0.57 mm/y ) , no radiographic evidence of pelvic osteolysis was seen . The Arthopor 2 cup performed well with respect to pelvic osteolysis , despite the presence of substantial polyethylene debris . The relatively high polyethylene wear rate is attributed in part to the younger patient population and the use of 32-mm femoral heads paired with thin polyethylene liners Background : The early experience with cementless total hip replacement led to design modifications to increase the initial press-fit and stability of the femoral component , to reduce the diameter of the femoral head , and to improve the acetabular component , including the locking mechanism of the shell and the quality of the polyethylene liner . We performed a prospect i ve study to assess the results in young patients who had been followed for a minimum of eight years after treatment with a primary total hip arthroplasty with a second-generation cementless prosthesis . Methods : Eighty patients ( 118 hips ) were included in the study . There were fifty-eight men and twenty-two women ; the mean age at the time of the operation was 46.8 years ( range , twenty-one to forty-nine years ) . We used a cementless Duraloc series-100 or 1200 acetabular component with or without screw fixation , a polyethylene liner with a 22-mm inner diameter , and a cementless Profile femoral component in all hips . The average duration of follow-up was 9.8 years ( range , eight to eleven years ) . Clinical follow-up ( with use of the Harris hip score ) and radiographic follow-up were performed at six weeks ; at three , six , and twelve months ; and yearly thereafter . Linear and volumetric wear were measured , and bone-remodeling and osteolysis were assessed . Results : The average Harris hip score improved from 48.8 points preoperatively to 92 points at the final follow-up examination . The prevalence of transitory thigh pain was 10 % ( twelve of 118 hips ) . There was no aseptic loosening . One hip was revised because of recurrent dislocation . The average amount of linear wear was 1.18 mm , and the average wear rate was 0.12 mm/yr . Fourteen hips ( 12 % ) had osteolysis in the calcar femorale and eleven hips ( 9 % ) had acetabular osteolysis , but all of the osteolytic lesions were < 1 cm 2 . Conclusions : The mechanical fixation of the anatomic fit cementless Profile stem was excellent in this study of young patients who were particularly difficult to treat because of a high prevalence of osteonecrosis and developmental dysplasia . Although there was no aseptic loosening of the components and a relatively low prevalence of osteolysis , there was a high rate of linear wear of the polyethylene liner . Level of Evidence : Therapeutic study , Level IV ( case series [ no , or historical , control group ] ) . See p. 2 for complete description of levels of evidence One hundred consecutive primary total hip arthroplasties performed with use of a porous-coated anatomic total hip prosthesis , fixed without cement , in ninety-one patients were followed prospect ively for a minimum of ten years . At the time of the most recent follow-up , twenty patients ( twenty-three hips ) had died and seventy-one patients ( seventy-seven hips ) were living . The average age of the living patients was sixty-six years ( range , thirty-two to ninety-two years ) , and their average Harris hip score was 84 points ( range , 33 to 100 points ) . Twelve percent ( nine ) of the seventy-seven hips were found to be associated with pain in the thigh when the patients were specifically question ed by the examiner . Eleven hips were revised during the follow-up period . Only the acetabular component was revised in six hips , only the femoral component was revised in one hip , and both the femoral and the acetabular components were revised in four hips . Of the ten acetabular revisions , one was performed because of acute dissociation of the component and eight , because of a combination of polyethylene wear , osteolysis , and loosening ; the tenth acetabular revision consisted of exchange of the liner and curettage and bone-grafting of the osteolytic area . Of the five femoral revisions , two were performed because of loosening and three , because of extensive osteolysis of the proximal aspect of the femur . Including the revised components , twelve acetabular components and five femoral components had radiographic evidence of aseptic loosening . Acetabular osteolysis occurred in seventeen hips . Femoral osteolysis occurred in thirty-nine hips : in the proximal aspect of thirty-one hips , in the distal aspect of four , and in both the proximal and the distal aspect of four . The durability of the femoral fixation documented in this study is especially encouraging in view of the fact that this was our initial experience with devices fixed without cement and that a so-called first-generation femoral component was used . However , the study also demonstrated that not all acetabular components fixed without cement function well over the long term and that specific design considerations ( adequate initial fixation , congruency between the liner and the shell , an optimum shell-liner capturing mechanism , and a smaller femoral head ) are warranted Abstract Restoration of femoral offset and acetabular inclination may have an effect on polyethylene ( PE ) wear in THA . We therefore assessed the effect of femoral offset and acetabular inclination ( angle ) on acetabular conventional ( not highly cross-linked ) PE wear in uncemented THA . We prospect ively followed 43 uncemented THAs for a minimum of 49 months ( mean , 64 months ; range , 49–88 months ) .  Radiographs were assessed for femoral offset , acetabular inclination , and  conventional PE wear . The mean ( ± st and ard deviation ) linear wear rate in all THAs was 0.14 mm/year ( ± 0.01 mm/year ) and the mean volumetric wear rate was 53.1 mm3/year ( ± 5.5 mm3/year ) . In THAs with an acetabular angle less than 45 ° , the mean wear was 0.12 mm/year ( ± 0.01 mm/year ) compared with 0.18 mm/year ( ± 0.02 mm/year ) in those with a reconstructed acetabular angle greater than 45 ° . Reproduction of a reconstructed femoral offset to within 5 mm of the native femoral offset was associated with a reduction in conventional PE wear ( 0.12 mm/year versus 0.16 mm/year ) . Careful placement of the acetabular component to ensure an acetabular angle less than 45 ° in the reconstructed hip allows for reduced conventional PE wear . Level of Evidence : Level II , prospect i ve study . See Guidelines for Authors for a complete description of levels of evidence This article presents a prospect i ve clinical and radiologic review of 55 total hip replacements in 50 patients in which the cementless Harris-Galante porous-coated acetabular component was used . All patients were 50 years of age or younger . The cups were inserted by 15 different surgeons . The minimum followup was 5 years , with a mean of 7 years . No acetabular component has been revised for loosening , and none have migrated . Three ( 5.5 % ) cups have progressive bone-component radiolucent lines , two ( 3.6 % ) of which are complete . Six ( 10.9 % ) acetabular liners have been replaced for excessive polyethylene wear , and an additional four ( 7.3 % ) show sufficient wear to produce obvious radiographic eccentricity of the femoral head . All of the revised liners had 32-mm femoral heads and an initial polyethylene thickness of less than 6 mm . Although the results reflect excellent fixation of this component in the medium term , the incidence of exchange of the polyethylene liner for excessive wear is unacceptably high . The reduction in polyethylene thickness associated with the use of a metal-backed component and a 32-mm articulation was one of the factors contributing to the accelerated wear patterns seen in this series We selected r and omly a consecutive series of 162 patients requiring hip replacement to receive either a cementless , hemispherical , modular , titanium acetabular cup or a cemented , all-polyethylene cup . These replacements were performed by two surgeons in four general hospitals . The same surgical technique was used and a 26 mm metal-head femoral component was used in every case . After exclusions , 115 hips were studied for differences in rates of wear and osteolysis . The mean clinical follow-up was eight years and the mean radiological follow-up , 6.5 years . The cementless cups  wore at a mean rate of 0.15 mm per year and the cemented cups at 0.07 mm per year . This difference was significant ( p < 0.0001 ) . Our findings in this mid-term study suggest that cementless cups  wear more than cemented cups One hundred nineteen consecutive primary hybrid total hip arthroplasties with a precoated femoral component were performed by one surgeon in 100 patients and followed up prospect ively . Ninety-eight hips in 82 patients ( mean age , 67 years ) were evaluated clinical ly and radiographically at a mean of 6.5 years ( range , 5 - 9 years ) . The hips were evaluated clinical ly using the Harris hip score , and radiographs were evaluated for femoral cement grade , loosening , and osteolysis . Ninety-five hips remained in place at the most recent followup . Two femoral components were revised for definite loosening , and one well fixed femoral component was removed because of late hematogenous infection . Excluding the three hips that were revised , the clinical result was excellent or good in 79 hips ( 83 % ) , fair in 12 hips ( 13 % ) , and poor in four hips ( 4 % ) . All other femoral components were well fixed . There were defects of the cement mantles ( C1 and C2 ) in 90 hips . No femoral component had a stem and cement radiolucent line . Focal femoral osteolysis was seen in only two hips . One acetabular component was removed at 5 years because of late hematogenous infection . One acetabular component had asymptomatic migration . The remaining 96 acetabular components were well fixed . Focal acetabular osteolysis was present in four hips . The mean linear polyethylene wear rate was 0.06 ( + /- 0.05 ) mm per year . In contrast to other reports of early failure and osteolysis , the use of a precoated femoral component in this study did not adversely affect the fixation of hybrid total hip arthroplasty , with definite failure of only 2 % ( two of 98 ) of the femoral components Background Isolated acetabular revisions using st and ard cups are at risk of dislocation . The introduction of a nonconstrained dual-mobility cup was design ed to improve prosthetic stability without increasing loosening rates , but it is unclear whether the risk of dislocation is reduced . Questions / purpose sWe therefore determined : ( 1 ) if the rate of dislocation in isolated acetabular revisions is lower with a dual-mobility cup , ( 2 ) implant survival , ( 3 ) patient function , and ( 4 ) radiographic incidence of migration , loosening , and osteolysis . Methods We prospect ively followed 33 selected patients who underwent isolated acetabular revisions with a minimum of 2 years ’ followup ( mean , 3 years ; range , 2–5 years ) . In 24 patients a stainless steel dual-mobility cup was cemented into an antiprotrusio cage , whereas in nine we used a hyaluronan dual-mobility revision cup with a foramen hook and superior and posterior flanges screw fixations . We determined Harris hip ( HHS ) and WOMAC scores and examined radiographs for migration , loosening , and osteolysis . Results There were no dislocations . Survivorship rates of the femoral and acetabular components were 97 % at 5 years ; the rerevision rate for any reason was 3 % . At last followup , the mean HHS increased from 48 points preoperatively to 86 points . No patients had progressive osteolysis , component migration , or loosening on radiographs . Conclusion In this select group of isolated acetabular revisions , our data suggest the use of a dual-mobility cup reduced the risk of dislocation without increasing loosening from 2 to 5 years . Level of Evidence Level IV , therapeutic study . See the Guidelines for Authors for a complete description of levels of evidence To evaluate different modes of cementless fixation of hemispherical cups , we operated on 87 hips in 81 patients using 4 different means of cup fixation . The hips were r and omly assigned to fixation with press-fit technique only ( PF ) , or with augmentation with screws ( S ) , pegs ( P ) , or hydroxyapatite ( HA ) coating . The patients were evaluated with radiostereometric analysis ( RSA ) for cup migration and wear , conventional radiography for osteolysis , and Harris Hip Score for clinical outcome over 5 years . The fixation of the cups did not differ between the groups , but HA showed a tendency to decrease proximal migration . HA-coated cups displayed the best interface with hardly any signs of radiolucent lines , indicating a superior sealing effect of the HA coating . Cups with screws or pegs had more radiolucent lines and osteolytic lesions than the other groups . Radiolucent lines were correlated to higher proximal migration , young age , and female gender ( r2=.2 ) . The wear rate of the ethylene oxide-sterilized polyethylene liner was high ( 0.2 mm/y ) but did not differ between the groups . Two cups with a perioperative fracture of the acetabular rim showed large initial migration but stabilized thereafter The Anatomique Benoist Girard ( ABG ) I total hip arthroplasty has been widely used in Europe since 1989 . Two recent midterm reports have shown high rates of component failure secondary to polyethylene wear . To further investigate this issue , our study prospect ively follows 157 consecutive primary total hip arthroplasties using the ABG I prosthesis at an average follow-up of 10 years .  Clinical outcomes have been excellent , although the incidence of thigh pain was 7.2 % . Radiographic evaluation of the cup showed eccentric polyethylene wear in 93.6 % of the patients . The average polyethylene linear wear was 2.40 mm , whereas the average annual wear rate was 0.25 mm/y . There were 7 hips ( 5.6 % ) with severe periacetabular osteolysis . Nine revisions were performed for loosening or wear . The overall component survival rate was 92.6 % . The overall survival rate was 92.6 % ( confidence interval , 78.55 - 96.47 ) for the acetabular component and 96.3 % ( confidence interval , 85.67 - 100 ) for the femoral component . Although the clinical and radiographic results of the ABG I total hip arthroplasty in this series have been acceptable , high rates of polyethylene wear , most likely related to sterilization by gamma-irradiation in air , have been the limiting factor in the long-term success of this design In a matched-pair study of primary total hip arthroplasty , 45 all-polyethylene cemented acetabular components were compared with 45 cementless , hemispheric , titanium acetabular components .  At 9 to 12 years , 1 of the cemented acetabular components was revised for aseptic loosening , and 14 ( 31 % ) were radiographically loose . Nine ( 20 % ) cemented acetabular components had pelvic osteolysis . In the cementless acetabular component group , 2 well-fixed components were revised . No components were radiographically loose , and 3 ( 7 % ) had pelvic osteolysis . Thirty-eight ( 97 % ) of the patients in each group were satisfied with the surgery . The clinical results of the cemented and cementless components were excellent . The cementless components had less loosening ( P < .001 ) than the cemented components Purpose To evaluate early performance of contemporary dual mobility acetabular systems with second generation annealed highly cross-linked polyethylene for primary hip arthroplasty of patients under 55 years of age . Methods A prospect i ve observational five years study across five centers in Europe and the USA of 321 patients with a mean age of 48.1 years was performed . Patients were assessed for  causes of revision , hip instability , intra-prosthetic dissociation , Harris hip score and radiological signs of osteolysis .  Results There were no dislocations and no intra-prosthetic dissociations . Kaplan Meier analysis demonstrated 97.51 % survivorship for all cause revision and 99.68 % survivorship for acetabular component revision at five years . Mean Harris hip score was 93.6 . Two acetabular shells were revised for neck-rim implant impingement without dislocation and ten femoral stems were revised for causes unrelated to dual mobility implants . Conclusion Contemporary highly cross-linked polyethylene dual mobility systems demonstrate excellent early clinical , radiological , and survivorship results in a cohort of patients that dem and high performance from their implants . It is envisaged that DM and second generation annealed HXLPE may reduce THA instability and wear , the two most common causes of THA revision in hip arthroplasty UNLABELLED The outcome of a single design of dual mobility cup was prospect ively evaluated in a continuous series of 994 revision THAs with respect to dislocation and intra-prosthetic dislocation ( IPD ) . At a 7.3-year mean follow-up , the dislocation rate was 1.5 % and the IPD rate was 0.2 % . The 2 IPD occurred in acetabular-only revisions and were related to a poor head-to-neck ratio with early impingement and wear at the polyethylene mobile component chamfer . Dual mobility cups demonstrated a low dislocation rate in revision THA but did not compensate for potential perioperative technical errors . In addition , IPD did not appear to be a concern with respect to the benefit in term of instability prevention though caution is advised in acetabular-only revision associated with a poor head-to-neck ratio . LEVEL OF EVIDENCE Therapeutic study -Level IV Ceramic-on-ceramic hip replacements might stress the bone interface more than a metal-polyethylene because of material stiffness , microseparation , and sensitivity to impingement . To ascertain whether this potentially increased stress caused an increased cup migration we compared a ceramic-on-ceramic with a metal-on-polyethylene implant for cup migration . Sixty one patients ( 61 hips ) undergoing THA for osteoarthritis were  r and omized to ceramic on ceramic ( Ce/Ce ) or cobalt-chromium on cross-linked polyethylene bearings ( PE ) in the same uncemented cup shell . Migration was followed with RSA . At 2 years we observed similar mean cup translations in the 3 directions ( 0.07 - 0.40 mm vs. 0.05 - 0.31 mm , Ce/Ce vs. PE ) , as well as similar rotations around the 3 axes ( 0.31 - 0.92 ° vs. 0.57 - 1.40 ° ) . WOMAC and SF-36 scores were also similar and no radiolucent lines or osteolysis found . The large migration seen in some cups in both implant groups will require close monitoring to ascertain the reasons . Mean proximal wear of the polyethylene liners measured 0.016 mm between 2 and 24 months . Our data suggest there is no increased cup migration in the ceramic-on-ceramic implant compared with the metal-on-polyethylene , and they seem an equally safe choice . However , the low wear measured with the more versatile and less expensive cross-linked polyethylene makes it a strong contender . Levels of Evidence : Therapeutic Level I. See the Guidelines for Authors for a complete description of levels of evidence In a prospect i ve study , the authors used a porous tantalum monoblock acetabular component for primary total hip arthroplasty between November 1997 and June 1999 . A total of 156 consecutive primary total hip arthroplasty were done in 143 patients younger than 75 years . A total of 151 hips had a follow-up time from 8 to 10 years . The average preoperative total Harris hip score of 44.0 + /- 13.8 increased to 97.0 + /- 6.2 at the latest follow-up . The average preoperative Oxford hip score of 43.3 + /- 6.5 improved to 13.9 + /- 2.3 at the latest follow-up . Radiographic evaluation including the Ein-Bild-Röntgen-Analyse ( EBRA ) digital system showed no radiographic evidence of gross polyethylene wear , progressive radiolucencies , osteolytic lesions , acetabular fracture , or component subsidence . There were 7 ( 4.5 % ) postoperative complications all unrelated to the acetabular component In a prospect i ve study , 93 unselected consecutive uncemented hip arthroplasties were performed in 80 patients using the  titanium-coated RM acetabular component and the CLS femoral component .  The mean age of the patients at operation was 52 years ( 28 to 81 ) . None were lost to follow-up . In the 23 patients who had died ( 26 hips ) only one acetabular component had been revised . In the 57 living patients ( 67 hips ) , 13 such revisions had been performed . Of the 14 revisions , seven were for osteolysis , five for loosening and two for infection . Survival analysis of this implant showed a total probability of survival of 83 % ( 95 % confidence interval 73 to 90 ) , with all revisions as the endpoint , and a probability of 94 % ( 95 % confidence interval 87 to 98 ) with revision for aseptic loosening as the endpoint , indicating reliable long-term fixation of the titanium-coated RM acetabular component Ninety patients ( 96 hips ) scheduled for THA were stratified to fixation of the acetabular component in three main groups of about equal size . Fluoride cement , porous coated press-fit cup with ceramic coating or Palacos cum Gentamicin cement were used . All patients received Spectron EF stem .  The migration of the cups and the femoral head penetration into the socket were measured with radiostereometric analysis . At 2 years the choice of fixation did not influence the migration or rotation of the cup .  Patients with compromised bone quality showed increased three-dimensional ( 3D or total ) migration . Proximal and 3D penetration rates were increased in cemented compared with the uncemented cups ( p<0.001 ) , which probably not could be related to the choice of fixation . Appearance of radiolucent lines was almost equal in the two cemented groups . Uncemented cups had less radiolucent lines at 2 years . Fluoride containing cement or uncemented fixation did not improve the early postoperative stability of the socket
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 .