Reproducibility of femoral offset following short stem and straight stem total hip arthroplasty. Comparison of Bone Remodeling Between an Anatomic Short Stem and a Straight Stem in 1-Stage Bilateral Total Hip Arthroplasty. [Periprosthetic femoral bone reaction after total hip arthroplasty with preservation of the collum femoris : CT-assisted osteodensitometry 1 and 3 years postoperatively]. Bone remodelling around the Metha short stem in total hip arthroplasty: a prospective dual-energy X-ray absorptiometry study Bone remodelling after femoral short stem implantation in total hip arthroplasty: 1-year results from a randomized DEXA study Effect of robotic milling on periprosthetic bone remodeling. No Difference in Periprosthetic Bone Loss and Fixation Between a Standard-Length Stem and a Shorter Version in Cementless Total Hip Arthroplasty. A Randomized Controlled Trial. [Two-year results of a modular short hip stem prosthesis--a prospective study]. Highly Crosslinked Polyethylene Does Not Reduce Aseptic Loosening in Cemented THA 10-year Findings of a Randomized Study The effect of surface coating of femoral prostheses implanted without cement: a 2- to 4-year follow-up study. Evaluation of a Femoral Stem with Reduced Stiffness: A Randomized Study with Use of Radiostereometry and Bone Densitometry Ultrashort versus Conventional Anatomic Cementless Femoral Stems in the Same Patients Younger Than 55 Years Antero-lateral minimal invasive (ALMI) approach for total hip arthroplasty technique and early results A prospective cohort study on the short collum femoris-preserving (CFP) stem using RSA and DXA Ten-year results with the Morscher press-fit cup: an uncemented, non-modular, porous-coated cup inserted without screws Primary total hip arthroplasty with a proximally porous-coated femoral stem. Clinical and radiographic outcomes of total hip arthroplasty with insertion of an anatomically designed femoral component without cement for the treatment of primary osteoarthritis. A study with a minimum of six years of follow-up. Cyclic therapy with etidronate has a therapeutic effect against local osteoporosis after cementless total hip arthroplasty. No adverse effects of early weight bearing after uncemented total hip arthroplastyA randomized study of 20 patients Stress-related femoral cortical and cancellous bone density loss after collum femoris preserving uncemented total hip arthroplasty: a prospective 7-year follow-up with quantitative computed tomography Poor outcome of the PCA and Harris-Galante hip prostheses. Randomized study of 171 arthroplasties with 9-year follow-up. [Effect of alendronate on periprosthetic bone loss after cemented primary total hip arthroplasty: a prospective randomized study]. Second-generation Extensively Porous-coated THA Stems at Minimum 10-year Followup
Bone stock-preserving short stem prostheses have gained importance in  total hip arthroplasty ( THA ) with the use of minimally invasive surgical procedures . Because of their metaphyseal fixation and their dependency on the calcar radius , it is unknown whether the femoral offset can be reproduced with the same accuracy following short stem vs st and ard stem THA . This study clarifies whether it is possible to restore the femoral offset using a short stem prosthesis ( Fitmore ; Zimmer , Warsaw , Indiana ) compared with a conventional straight stem prosthesis ( CLS ; Zimmer ) following minimally invasive implantation using an anterolateral approach . In a prospect i ve , r and omized , double-blinded study , 80 patients underwent THA using a short stem ( SS group ; n=40 ) or CLS implant ( control group ; n=40 ) . Follow-up examinations were conducted 6 weeks postoperatively . Radiological and functional outcomes were measured . Subjective assessment of quality of life was evaluated using the Harris Hip Score ( HHS ) , the Short Form 36-item health survey ( SF-36 ) , and the Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) . Pre- and postoperative comparison of the groups ' change in offset showed no significant differences ( SS group difference from pre- to postoperative , 6.1±6.5 mm ; control group difference from pre- to postoperative , 6.5±7.1 mm ; P=.93 ) . Group comparison after 6 weeks revealed no significant differences in HHS , SF-36 , or WOMAC . Based on these data , an equivalent reproducibility of the femoral offset was demonstrated following short stem and straight stem THA using a minimally invasive anterolateral approach . If the long-term results of short stems show a comparable survival , they represent a sensible alternative to st and ard stems BACKGROUND Femurs of dysplastic hips exhibit specific abnormalities , and use of modular or specially design ed components is recommended . An anatomic short stem was previously design ed specifically for dysplastic hips using 3-dimensional data acquired from dysplastic patients . To investigate effects of stem geometry on bone remodeling , we undertook a prospect i ve , r and omized study of patients who had undergone 1-stage bilateral total hip arthroplasty ( THA ) with the anatomic short stem on one side and a conventional straight stem on the other . METHODS The study included 36 patients who underwent the above THA procedure . We assessed bone mineral density as well as the presence of cancellous condensation or bony atrophy due to stress shielding based on the analysis of Gruen 's zones and newly defined equal-interval zones , at an average follow-up period of 9.2 years . RESULTS All stems were bone ingrown stable . Cancellous condensation was observed more proximally , and areas of bone atrophy were narrower on the anatomic short stem side than on the straight stem side . Bone mineral density values reflected results of cancellous condensation and stress shielding and were higher in more proximal zones on the anatomic short stem side than on the straight stem side . CONCLUSION Although radiographic results indicated good midterm outcomes of THA with both stems , the loading pattern differed . The anatomic short stem achieved its design purpose in terms of proximal fixation and load transfer and led to better preservation of the proximal femur BACKGROUND Short-stemmed cementless femoral components in total hip arthroplasty have been design ed to preserve the proximal femoral bone stock by load transfer to the femoral metaphysis . An in vivo method of computed tomography-assisted ( CT ) osteodensitometry after total hip arthroplasty is presented which differentiates between cortical and cancellous bone density ( BD ) changes around uncemented femoral components . PATIENTS AND METHODS Cortical and cancellous periprosthetic femoral BD ( mg Ca HA/ml ) was determined prospect ively in 31 patients at day 10 , 1 year and 3 years after total hip arthroplasty with preservation of the collum femoris ( C.F.P.-stem , Link , Hamburg , Germany ) using computed tomography-assisted osteodensitometry .  Clinical results ( Harris hip score ) and plain x-rays were assessed in all cases . RESULTS Progressive proximal cortical BD loss was observed between the 1 year ( Ø -8 % ) and 3 year ( Ø -22 % ) postoperative measurements . Distal to the trochanter minor no significant cortical BD changes were observed . Proximal cancellous BD decreased progressively between the 1 year ( Ø -33 % ) and 3 year ( Ø -45 % ) analyses . The Harris hip score improved from 45 points pre-operatively to 93 points at the 3 year follow-up . All x-rays showed signs of stable ingrowth . CONCLUSION Periprosthetic CT osteodensitometry has the technical ability to discriminate between cortical and cancellous bone structures with respect to strain-adapted remodeling . Progressive proximal cortical and cancellous BD loss indicates that metaphyseal fixation can not be achieved with the analyzed C.F.P. stem design . The lack of cortical BD loss below the trochanter minor suggests diaphyseal fixation of the implanted stem Purpose On the basis of positive clinical results with mid- and long-term follow-up using the Mayo short stem , the Metha neck-preserving stem ( BBraun , Aesculap , Tuttlingen , Germany ) was introduced . The purpose of this study was to vali date the implant design by direct acquisition of bone remodelling data from total hip arthroplasty ( THA ) recipients using dual-energy X-ray absorptiometry ( DEXA ) . Methods After power analysis , 25 patients were included in this prospect i ve study . Patients were examined clinical ly and underwent DEXA examinations preoperatively and postoperatively at one week , six months and one and two years after THA . Gruen zones were adapted to the short stem design ( R1–R7 ) . Results The Harris Hip Score ( HHS ) increased significantly by 31 points . No stem had to be revised . Bone mineral density ( BMD ) in the greater trochanter decreased significantly from 0.78 g/cm2 postoperatively to 0.72 g/cm2 two years after surgery . Marginal changes were seen in the lateral distal regions ( R4–R5 ) . In the minor trochanter region , BMD increased significantly after two years by 12.9 % . In the calcar region , BMD exceeded the baseline value by 6.1 % two years after implantation . Conclusions Stress shielding seems to occur at the greater trochanter due to the vast cross-section of the implant . However , the aim of proximal load transfer of the Metha stem seems to be partially achieved . DEXA analysis revealed a concentrated load distribution on the medial portion of the femur , which is an important region to guarantee long-term implant survival Introduction Short stem prostheses have been developed to preserve proximal femoral bone stock . This prospect i ve , r and omized study compared periprosthetic bone remodelling following short and straight stem implantation 1 year after surgery . Material s and methods One hundred and forty-four consecutive patients undergoing total hip arthroplasty were r and omized to either a Fitmore short or a cementless straight stem ( both Zimmer , Winterthur , Switzerl and ) . Periprosthetic bone mineral density ( BMD ) was measured using dual-energy X-ray absorptiometry performed the day before surgery and at 7 days , 3 months and 1 year postoperatively . Furthermore , the HHS and the WOMAC were obtained . Results One hundred and thirty-eight patients completed 1-year follow-up . Periprosthetic BMD changes at 1 year were most pronounced in the proximal medial region of interest ( ROI ) 7 with −17.2 % after short stem and −16.7 % after straight implantation ( p = 0.67 ) . However , there was significantly less BMD reduction in ROI 6 following short ( −4.7 % ) versus straight stem ( −10.8 % ) implantation ( p = 0.01 ) . There were no significant differences between the two groups in terms of the HHS and the WOMAC either before or after surgery . Conclusion One year after surgery , both stems showed an implant-specific periprosthetic bone remodelling . Nevertheless , proximal load transfer was more pronounced after short stem implantation than with a straight stem The ROBODOC system has provided better fit and fill of the stem and less destruction of the bony architecture than with manual surgery . These benefits might affect femoral periprosthetic bone remodeling . We evaluated the effects of robotic milling in cementless total hip arthroplasty ( THA ) in a longitudinal 24-month follow-up study using dual energy X-ray absorptiometry ( DEXA ) and plain radiographs of 29 patients ( 31 hips ) after ROBODOC THA and 24 patients ( 27 hips ) after manual THA with the same stem design . To minimize the influence of other factors on bone remodeling , only female osteoarthritis patients , who had no drugs that might affect bone metabolism were enrolled . Significantly less bone loss occurred at the proximal periprosthetic areas in the ROBODOC group . In zone 1 , the decrease was 15.5 versus 29.9 % using conventional rasping ; in zone 7 , the loss was 17.0 % with ROBODOC compared to 30.5 % with conventional rasping ( p < 0.05 ) . On radiographs , endosteal spot welds in the proximal medial portion were more pronounced in the ROBODOC group ( 48 vs. 11 % in the conventional group , p < 0.05 ) . Our results suggest that robotic milling is effective in facilitating proximal load transfer around the femoral component and minimizing bone loss after cementless THA BACKGROUND Cementless femoral stems in total hip arthroplasty provide dependable clinical and radiographic results in the treatment of osteoarthritis . Stem length might affect the preservation of proximal bone stock and stability . We hypothesized that a shorter stem decreases proximal bone loss without affecting implant stability . METHODS We r and omly assigned 60 patients aged between 50 and 70 years to either a st and ard cementless femoral stem or a 35-mm shorter version . Patients were followed with dual-energy X-ray absorptiometry , radiostereometric analysis , Harris hip score , Western Ontario and McMaster Universities Osteoarthritis Index score , and clinical follow-up at 3 , 6 , 12 , and 24 months . The trial is registered on Clinical Trials.gov/. RESULTS After 24 months , short stems had on average 3.8 % ( 95 % confidence interval , 1.2%-8.9 % ) more bone loss in zone 1 compared to st and ard stems ( P = .14 ) . In zone 7 , the bone loss was on average 6.5 % ( 95 % confidence interval , 6.6%-19.7 % ) higher compared to st and ard stems ( P = .33 ) . After 24 months , st and ard stems had migrated 0.93 mm ( range , 0.25 - 4.66 mm ) and short stems 0.93 mm ( range , 0.17 - 2.96 mm ; Student t-test after log transformation , P = .3 ) . Patient-reported outcome measures were similar in both groups . One patient in the st and ard stem group was diagnosed with infection , one with a posterior dislocation , and one with a deep venous thrombosis . No stems were revised . CONCLUSION There were no statistically significant differences in periprosthetic bone loss or fixation between the stems at 24 months AIM The short-term results of a prospect i ve , consecutive series of 50 cementless modular short hip stem endoprostheses  are reported . METHOD 48 cases were available for clinical and radiological follow-up at an average time of 2.4 years post-op . One patient did not consent to a follow-up investigation , 1 early revision was necessary 4 weeks post-op after a fall precipitating a periprosthetic fracture . RESULTS The average age at the time of THA was 54 years and the Harris hip score reached 95 points at the time of follow-up . One implant had aseptic loosening and 1 implant was revised due to a failure of the modular titanium neck adapter . An equal number of patients received modular neck adapters with neutral or 7.5 degrees retroversion . No 140 degrees neck and no anteverted neck adapters were used . Radiological results of the 2/3 porous coated hip stem showed a metaphyseal bone remodelling with hypertrophies in coated Gruen zones 3 ( 17 % ) and 6 ( 46 % ) and marked spot welds and increased bone density ( 86 % ) in the distal area of the coating . Primary implant migration between 2 and 10 mm was present in 7 cases due to a low osteotomy and implant position combined with an implant undersizing and lack of proximal-lateral support . At the time of the last follow-up these cases had no clinical symptoms with an average HHS of 96 points and with full bony integration . CONCLUSION Our results support the use of the investigated short hip stem for THA when the femoral bone quality and morphology support the metaphyseal anchoring concept . The surgical technique must avoid a stem position without proximal-lateral cortical contact to the femoral osteotomy , as this reduces primary implant stability . Further follow-up is necessary to vali date the long-term success of this procedure 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 A r and omized , concurrently controlled , prospect i ve , single-blinded , multicenter study was done to evaluate the effect of proximal surface coating of a femoral prosthesis on clinical and radiographic results of  cementless total hip arthroplasty ( THA ) .  The Profile femoral prosthesis ( DePuy , Warsaw , IN ) , an anatomic titanium alloy stem , was used in one of three configurations : ( 1 ) smooth , ( 2 ) porous coated , or ( 3 ) hydroxyapatite ( HA ) coated .  Ninety-one cases were enrolled in the study , with seven cases lost to follow-up and 79 cases available for clinical review with 24- to 48-month follow-up . The study shows that HA-coated stems performed as well , if not better than , porous-coated or smooth stems . Results show HA-costed stems with statistically superior total Harris hip scores ( microHA = 96.0 ) than smooth stems ( microS = 85.1 ) ( Student 's t-test , P = 0.004 ) . This was primarily due to differences between the functional score of the two groups ( microHA - 31.6 ; microS = 27.9 , P = 0.003 ) . Porous-coated stems were intermediate in performance ( microPC = 89.8 ) , with hip scores that were statistically indistinguishable from both smooth and HA-coated stems . Our data support the hypothesis that clinical differences exist and are attributable to the type of surface coating used for the cementless femoral components in THA Background : Femoral stems with reduced stiffness were introduced in total hip arthroplasty to facilitate proximal load transfer and thereby reduce periprosthetic bone loss . Poor fixation and unacceptably high revision rates turned out to be a major problem with these prostheses . The purpose of the present study was to evaluate the early performance of a low-modulus stem ( one that is less stiff ) with the potential to address the problem of fixation by the use of a surface coating . The coating consisted of a titanium porous mesh proximally covered with a mixture of hydroxyapatite and tricalcium phosphate . Methods : Thirty-nine men and twenty-six women ( sixty-eight hips ) with noninflammatory arthritis were studied . The patients were r and omized to receive either a porous-coated composite stem with reduced stiffness ( Epoch ) or a stiff stem with a porous coating ( Anatomic ) . Both stems were inserted without cement , had a ceramic coating on the proximal two-thirds , and were supplied with tantalum beads . At the time of the operation , tantalum markers were also placed into the proximal part of the femur . The patients were followed for up to two years after the operation and were evaluated with use of repeated radiostereometric measurements , measurements of bone-mineral density , conventional radiography , and Harris hip scores . Results : Both stems showed optimum fixation with median subsidence and stem rotations that were close to zero . Repeated measurements of bone-mineral density revealed early loss of bone mineral in all Gruen regions in both treatment groups . The loss of bone mineral around the Epoch stems was significantly reduced at two years in Gruen regions 1 , 2 , 6 , and 7 ( p < 0.0005 to 0.04 ) . Measurements on postoperative radiographs showed no difference in stem positioning or fill , but the Epoch stems had significantly more endocortical contact on both the anteroposterior ( p < 0.0005 ) and the lateral radiograph ( p = 0.02).At two years postoperatively , the Epoch stems had fewer sclerotic lines surrounding the stem ( p £ 0.002 ) and less sclerosis at the tip of the prosthesis ( p = 0.001 ) compared with the Anatomic stems . The clinical results in terms of the Harris hip score , which was determined in all hips , and pain or discomfort , which was evaluated in thirty-seven hips treated at the same hospital , were not found to be different , with the numbers available . Conclusions : Contrary to previous studies of other design s with reduced stiffness , the Epoch stem achieved excellent primary fixation . Despite this rigid fixation , the proximal loss of bone-mineral density was less than that associated with the stem with a stiffer design . These results should encourage additional long-term studies with a larger patient population Background Because the clinical and radiographic performance of an ultrashort anatomic cementless stem has been investigated in only two r and omized controlled studies , well- design ed trials should aim for a thorough comparison of the outcomes of ultrashort anatomic cementless and conventional anatomic cementless stems . Questions / purpose sThe purpose s of this study were to compare ( 1 ) the clinical results , including Harris hip score , thigh pain , and WOMAC index score , ( 2 ) radiographic results , ( 3 ) bone mineral density ; and ( 4 ) proportions of patients undergoing revision of a THA using an ultrashort anatomic cementless stem versus a conventional anatomic cementless stem  in the same patients who underwent bilateral sequential THAs under the same anesthetic . Methods Two hundred patients ( mean age , 53 years ; range , 26–54 years ) who underwent bilateral sequential THAs received an ultrashort anatomic cementless stem in one hip and a conventional anatomic cementless stem in the contralateral hip . From January 2004 to December 2005 , we performed 524 same-day bilateral short and conventional anatomic cementless THAs  in 262 patients , of whom 212 ( 81 % ) participated in this study . Five patients were lost to followup before 2 years , five were lost between 2 to 10 years , and two were lost between 10 to 13 years , leaving 200 patients . Patients who had end-stage bilateral hip disease and were younger than 55 years were selected for inclusion . The predominant diagnoses were osteonecrosis ( 118 patients , 59 % ) and osteoarthritis ( 44 patients , 22 % ) . One hundred thirty-eight were men and 62 were women . At the time of each followup , the patients were assessed clinical ly and radiographically . In addition , each patient completed the WOMAC and the University of California Los Angeles ( UCLA ) activity scores . The minimum followup was 10 years ( mean , 11.8 years ; range , 10–13 years ) . Followups were done in person , with all images and followup clinic notes . Based on the power analysis , we estimated a sample size of 178 hips was needed in each group to detect a 3-point difference in the Harris hip score with 80 % power . Results At the latest followup , there were no differences between the two groups regarding the mean Harris hip scores ( 94 versus 94 points ; p = 0.189 ) , mean WOMAC scores ( 17 versus 16 points ; p = 0.191 ) , or mean UCLA activity scores ( 9 versus 9 points ; p = 0.381 ) . Two patients in the ultrashort stem group and one patient in the conventional stem group had severe ( 9 points ) thigh pain , and 30 patients ( 15 % ) in the conventional stem group had mild thigh pain ( 2 or 3 points ) after vigorous exercise . Bone mineral density in the ultrashort and conventional stem groups , respectively , was greater in the ultrashort stem group than in the conventional stem group . Bone mineral density in Zone 1 at 12 years was 3.29 versus 1.88 g/cm2 ( p = 0.021 ) , and 2.97 versus 0.91 g/m2 in Zone 7 ( p = 0.001 ) . With the numbers available , there were no differences between the stem design s in terms of the proportion undergoing revision ( one hip , 0.5 % , in the short-stem group versus one hip , 0.5 % , in the conventional group ; p = 1.881 ) . Conclusions At followup into the second decade , ultrashort stems showed no differences from conventional cementless stems in terms of vali date d outcomes scores or fixation , although less stress shielding was observed . Reduction of stress shielding may reduce the long-term risk of periprosthetic fracture , but this was not shown in our study .Level of Evidence Level I , therapeutic study Introduction : Minimally invasive surgery represents one of the most recent techniques to have emerged within THA . In conventional THA , the incision typically measures 15–20 cm . Minimal invasive approach defined as less invasive to the skin , muscles , or bone may reduce complications and improve recovery time . A number of different approaches and methods have been described in literature . Purpose : This is a prospect i ve study describing the technique and early results of the modified antero-lateral minimal invasive ( ALMI ) approach and comparing our results to the results of other investigators interested in minimal invasive THA . Material s and methods : Seventy-five consecutive primary total hip arthroplasties ( cemented and cementless ) were done through a modified ALMI approach ( 6–8 cm ) , in which we kept the hip abductors intact . Neither special instruments nor specially design ed prostheses were needed . Minimum follow-up was 12 months . Results : The mean Harris hip score for patients after 12-month follow-up was 90 while the mean Merle d’Abugine mean score was 16.5 . Both scores reached almost the maximum values within 3 months after surgery . The cup abduction angle for 70 % patients was between 35 ° and 45 ° . No femoral stem mal-alignment was recorded . The mean operative time of cemented prosthesis was 65 min while that of the cementless prosthesis was 55 min . No wound complications or dislocations were recorded . All the patients were allowed to weight bear in the second post-operative day and involved in an early rehabilitation program . Conclusion : ALMI hip approach with sparing of hip abductors is safe and gives excellent orientation for positioning of prosthesis components . It also allows early and smooth post-operative rehabilitation with fast recovery of the patient in terms of weight bearing Background and purpose Short femoral stems have been introduced in total hip arthroplasty in order to save proximal bone stock . We hypothesized that a short stem preserves periprosthetic bone mineral density ( BMD ) and provides good primary stability . Methods We carried out a prospect i ve cohort study of 30 patients receiving the collum femoris-preserving ( CFP ) stem .  Preoperative total hip BMD and postoperative periprosthetic BMD in Gruen zones 1–7 were investigated by dual-energy x-ray absorptiometry ( DXA ) , stem migration was analyzed by radiostereometric analysis ( RSA ) , and the Harris hip score ( HHS ) was determined . Results 2 patients were excluded intraoperatively and 1 patient was revised due to a deep infection , leaving 27 patients for analysis . The mean HHS increased from 49 ( 24–79 ) preoperatively to 99 ( 92–100 ) after 2 years . DXA after 1 year showed substantial loss of BMD in Gruen zone 7 ( –31 % ) , zone 6 ( –19 % ) , and zone 2 ( –13 % , p < 0.001 ) compared to baseline BMD determined immediately postoperatively . The bone loss in these regions did not recover after 2 years , whereas the more moderate bone loss in Gruen zones 1 , 3 , and 5 partially recovered . There was a correlation between low preoperative total hip BMD and a higher amount of bone loss in Gruen zones 2 , 6 and 7 . RSA showed minor micromotion of the stem : mean subsidence was 0.13 ( 95 % CI : –0.28 to 0.01 ) mm and mean rotation around the longitudinal axis was 0.01º ( 95 % CI : –0.1 to 0.39 ) after 2 years . Interpretation We conclude that substantial loss in proximal periprosthetic BMD can not be prevented by the use of a novel type of short , curved stem , and forces appear to be transmitted distally . However , the stems showed very small migration — a characteristic of stable uncemented implants 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 BACKGROUND The use of cementless , proximally porous-coated femoral stems for total hip arthroplasty has increased in popularity . The purpose of the present report was to examine the five to ten-year results associated with the use of a so-called second-generation circumferentially proximally porous-coated titanium-alloy stem . METHODS Between 1991 and 1994 , 123 Harris-Galante Multilock femoral stems were implanted in 101 patients . The average age of the patients at the time of surgery was 53.8 years . The patients were followed prospect ively and were reevaluated at a minimum of five years postoperatively . No patient was lost to follow-up . Twenty-five patients ( thirty hips ) were interviewed by telephone , and four patients ( five hips ) died during the study period because of problems that were unrelated to the operation . The remaining seventy-two patients ( eighty-eight hips ) had a minimum of five years of clinical and radiographic follow-up . RESULTS The average duration of follow-up was seventy-eight months . At the time of the most recent follow-up , the average Harris Hip Score was 95 points . Eighty-seven ( 99 % ) of eighty-eight stems were biologically stable , with eighty-four hips ( 95 % ) having osseous ingrowth and three hips ( 3 % ) having stable fibrous fixation . One stem was revised because of loosening . Thirty-three hips ( 38 % ) had minimal proximal osteolysis , and no hip had diaphyseal osteolysis . Seventy-two hips ( 82 % ) had some degree of stress-shielding in the proximal metaphysis , but only two hips had cortical resorption . None of these patients required additional surgery , and all reported a satisfactory outcome . CONCLUSIONS Given the young age and high activity level of these patients , this stem fared well : the levels of patient function and satisfaction were high , the rates of loosening and revision were very low , and distal osteolysis did not occur . Osseous fixation occurred reliably . Proximal stress-shielding was seen but did not seem to be clinical ly important We evaluated the clinical and radiographic outcomes of 100 consecutive primary total hip arthroplasties in which a proximally coated anatomically design ed femoral component was fixed without cement for the treatment of primary osteoarthritis . The minimum duration of follow-up was six years ( average , 7.1 years ) . The eighty-eight patients who had the arthroplasties were followed prospect ively with a st and ard clinical evaluation that involved use of the Harris hip score and a radiographic evaluation based on the criteria of the Hip Society . Bone ingrowth was evaluated with the method of Engh et al. The average age of the patients at the time of the operation was 62.6 years ( range , thirty-nine to eighty-four years ) . Fifty-one patients were men and thirty-seven were women . The average preoperative Harris hip score was 48 points , with an average pain score of 15 points and an average function score of 26 points . Nonmechanical complications that necessitated a revision operation included one deep hematogenous infection , one late periprosthetic fracture , and a 0.5-inch ( 1.27-centimeter ) limb-length discrepancy . At the time of the most recent follow-up , the average Harris hip score was 96 points , with an average pain score of 42 points and an average function score of 45 points . The prevalence of pain in the anterior part of the thigh was 5 percent ( five hips ) . One patient had a revision of the femoral component because of aseptic loosening , and one had a revision of the acetabular component because of recurrent dislocations . Radiographic assessment revealed consistent evidence of proximal bone ingrowth . No complete radiolucent line was identified , except around the stem that had loosened . Twenty-seven femoral components were associated with slight pedestal formation . No osteolytic lesion of the femur was identified . Nonprogressive pelvic osteolysis was identified in four hips , but none of the lesions were more than two millimeters in diameter . None of the acetabular components migrated , and no radiolucent line of more than two millimeters in thickness was seen around any acetabular cup . The data from this study , in which the minimum duration of follow-up was six years , indicate that the anatomically design ed prosthesis can provide good results , with low prevalences of pain in the thigh and loosening of the component , in younger , active patients Proximal bone resorption around the femoral stem is one of the major complications of cementless total hip arthroplasty ( THA ) . The potential complications result ing from proximal bone resorption include femoral fracture and late stem loosening . The purpose of this study was to evaluate the effects of cyclic therapy with etidronate on periprosthetic bone mineral density ( BMD ) after cementless THA . Fifty-two patients who had undergone cementless THA were r and omized for this study . Group A consisted of 30 hips in 29 patients without osteoactive drugs . Group B consisted of 23 hips in 23 patients with cyclic therapy with etidronate  ( i.e. , 400 mg/day of oral etidronate for 2 weeks followed by 12 weeks of 500 mg/day of calcium lactate and repeated every 14 weeks ) , one of whom was excluded from the study because of side effects attributed to the drug .  Periprosthetic BMD in seven regions of interest based on the zones of Gruen et al. ( Clin . Orthop . 141 ( 1979 ) , 17 - 27 ) was measured with dual energy X-ray absorptiometry ( DXA ) at 3 weeks , 6 months , and 12 months postoperatively . The postoperative decreases of BMD in group B were significantly lower than those in group A in zones 1 and 7 ( P < 0.05 and P < 0.05 , respectively ) at 6 months and in zones 1 , 2 , 6 , and 7 ( P < 0.05 , P < 0.05 , P < 0.05 , and P < 0.001 , respectively ) at 12 months . The BMD change appeared to be stabilized at 6 months in all zones in group B , while in group A there was a progressive decrease of average BMD ( 6.1 % ) in zone 7 between 6 months and 12 months . These findings suggested that cyclic therapy with etidronate may help to reduce the resorptive changes in the proximal part of the femur after cementless THA . Further follow-up study with larger population s will be required to define the potential efficacy of intermittent cyclic etidronate therapy on postoperative bone loss BACKGROUND Few guidelines are available whether early weight-bearing after an  uncemented total hip arthroplasty ( THA ) can be recommended or not . Stability and ingrowth may be jeopardized by immediate loading of the implant while functional recovery may be promoted and periprosthetic demineralization reduced . PATIENTS AND METHODS We did a prospect i ve study of 20 patients who were operated on with a hydroxyapatite-coated ( HA ) , uncemented total hip arthroplasty with a tapered stem because of unilateral arthrosis , and r and omized the patients to the immediate ( I ) or late ( L ) weight-bearing ( after 3 months ) group . The shoe on the operated side was equipped with an auditory device signaling when the patient placed a load on the extremity . The clinical assessment was done with the Harris hip score at the time of the operation and after 12 and 24 months . Radiographs and dual-energy x-ray absorptiometry ( DEXA ) were evaluated for migration , femoral remodeling and bone mineral density ( BMD ) after 3 , 6 , 12 and 24 months .  Tc-scintigraphy  was done after 6 , 12 and 24 months . RESULTS Postoperatively , the Harris hip score showed no group difference . After 3 months , we noted a large reduction in BMD around the stem prosthesis . This was most marked in the proximal regions and the bone loss was significantly larger in zone 1 , 4 and 5 in the L group . Distally , the BMD normalized with time , but the loss of bone persisted in the proximal zones after 24 months . An initial increase in the scintigraphic uptake ratio in all zones in both groups declined with time , but it was still increased on the operated side after 24 months . Several radiographic signs of bone remodeling were seen , but the patterns were similar in both groups . INTERPRETATION We found no adverse effect of immediate weight bearing with this prosthesis Purpose Bone loss around uncemented femoral components is suspected to precede implant loosening and contribute to problems in revision surgery .  Short-stemmed cementless femoral components are design ed to preserve proximal femoral bone stock and ultimately the longevity of the prosthesis . Methods With quantitative computed tomography-assisted osteodensitometry , we prospect ively analyzed femoral cortical and cancellous bone density ( BD ) and contact area changes of an uncemented collum femoris preserving stem ( n = 38 ) 10 days , 1 , 3 and 7 years post-operatively . Results Seven years post-operatively  , cancellous BD ( mg CaHA/mL ) had decreased by as much as −66 % and cortical BD by up to −27 % at the metaphyseal portion of the femur ; the decrease was progressive between the 1- and 3-year examinations and halted thereafter . Contact area ( in % out of a possible 100 % ) decreased proximally between the 1- and 3-year follow-up . Conclusion Proximal cortical and cancellous bone density loss and decrease of contact area indicate that metaphyseal fixation can not be achieved . The lack of cortical BD loss and increase of contact area values below the trochanter minor suggest diaphyseal fixation 155 patients ( 171 hips ) with a mean age of 50 years ( 24 - 64 ) were r and omized to uncemented PCA ( 84 hips ) or Harris-Galante type I ( 87 hips ) total hip arthroplasty .  Clinical and radiographic evaluations were done regularly . The improvements in the Harris hip and pain scores did not differ . Osteolysis developed in 5 PCA and 17 Harris-Galante hips . 13 hips in the PCA and 16 in the Harris-Galante ( HG ) group were revised because of mechanical failures and 1 hip ( HG ) because of infection after a mean follow-up of 9 years . Decreased 10-year survival rate , based on revision as end-point , was noted for the PCA ( 85 % ) , compared with the Harris-Galante cup ( 99 % ) . The corresponding survival rate of the PCA stem ( 96 % ) was higher than that observed for the Harris-Galante design ( 86 % ) . When radiographic failures were included , the survival rates of the 4 different components dropped to between 73 % and 94 % . These findings indicate that further revisions will be necessary and continuous radiographic follow-up is indicated to enable revision before severe bone destruction has occurred . Although the PCA and the Harris-Galante design s differed as regards the survival of the individual components , the overall clinical and radiographic survival rates of these cementless total hip arthroplasties were poor PURPOSE OF THE STUDY Bone remodeling and osteolysis around total hip prostheses , with its inevitable corollary , prosthesis loosening , remains a difficult problem in orthopedic surgery . Alendronate ( bisphosphonate ) has proven its efficacy for the treatment of osteoporosis of the lumbar spine and femoral neck . A few in vitro studies have pointed out its inhibiting effect on particle-induced osteolysis . In vivo , one study has demonstrated its usefulness in preventing osteolysis around non-cemented total hip arthroplasties ( THA ) . The purpose of this work was to study the efficacy of this agent for the prevention of changes in peri-prosthetic bone mineral density ( BMD ) after primary THA . MATERIAL AND METHODS The study series included 38 patients with degenerative hip disease who underwent THA . The patients were r and omized in double-blind fashion to two treatment arms : 10 alendronate and 600 mg calcium per day for 2 years ( 20 patients ) or placebo and 600 mg calcium per day for 2 years ( 18 patients ) . Conventional x-rays and x-ray biphotonic absorptiometry ( DPX ) was performed on day four postop and at 3 , 6 , 12 , and 24 months postop . The periprosthetic zones described by Grüen were used for analysis . RESULTS DPX demonstrated a significant reduction in BMD in all patients included in the study . The bone loss was the same in both groups during the early postoperative period reaching maximum loss at 3 months . Differences were observed after this time . In the placebo group , bone loss reached a plateau at 6 months then BMD started to increase progressively , reaching 12.7 % bone loss at 2 years follow-up ( p<0.002 ) . In the alendronate group , there was no plateau , BMD increased continuously starting from three months and reached 6.857 % bone loss at 2 years ( p<0.003 ) . DISCUSSION Administration of alendronate led to a significant reduction in peri-prosthetic bone loss at 2 years follow-up . These results are the first to our knowledge demonstrating the beneficial effect in vivo of alendronate on bone behavior around cemented THAs . CONCLUSION This beneficial effect observed in vivo should be confirmed in further studies including a larger number of patients and longer follow-up . The action of alendronate could facilitate and even retard revision surgery by preserving bone stock The relatively high prevalence of thigh pain and stress shielding associated with the AML porous-coated cementless femoral component led to the development of the Prodigy ® , a femoral component with more extensive porous-coating and a distal polished bullet tip with medial diaphyseal relief to potentially decrease the flexural rigidity . We prospect ively evaluated a cohort of 100 consecutive cementless total hip arthroplasties performed using this device . The minimum followup was 10 years ( mean , 11.4 years ; range , 10–12 years ) . At 10-year followup , 69 of the 86 patients ( 82 hips ) were living , 14 patients with 15 hips were deceased , and three patients with three hips were lost to followup . No hips required a stem revision . Two patients ( two hips ) complained of thigh pain . All hips were bone ingrown . Distal tip radiolucencies and osteolysis occurred in 13 hips ( 17 % ) and none , respectively . Twenty-one hips ( 28 % ) demonstrated moderate or severe stress shielding . Only further followup will determine if this could be a clinical problem or one with revision surgery . These results encourage the authors to continue using second-generation extensively coated stems in their primary total hip arthroplasty constructs . Level of Evidence : Level III , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence
Our results suggest that compared with CS , SS may provide superior bone remodelling and similar survival rates and clinical outcomes .
However , the short-term follow-up of the included studies was inadequate to determine the long-term performance of SS
OBJECTIVE Cementless total hip arthroplasty (  THA ) is associated with reliable clinical results and high patient satisfaction .
Short-stem prostheses ( SS ) were design ed to achieve superior preservation of proximal bone stock and stability compared with those of conventional-stem prostheses ( CS ) .
This meta- analysis was conducted to determine the proximal bone remodelling , revision rate , Harris Hip Score , radiolucent line and maximum total point motion values of both SS and CS for primary THA .