human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Benefits of a direct anterior approach ( DAA ) versus a posterior-lateral ( PA ) approach to THA were assessed in a single-surgeon , IRB-approved , prospect i ve , r and omized clinical study . Subjects ( 43 DAA and 44 PA ) were evaluated at 6 weeks , and 3 , 6 and 12 months . The primary end point was ability to climb stairs normally and walk unlimited at each time point . Secondary end points included assessment by several outcome instruments . DAA subjects performed better during the immediate post-operative period ; they had lower VAS pain scores on the first post-operative day , more subjects climbing stairs normally and walking unlimited at 6 weeks , and higher HOOS Symptoms scores at 3 months . There were no significant differences between groups at later time points . Findings confirm previous reports of benefits of DAA versus PA in early post-operative phases The advantages of minimally invasive surgical approaches for total hip arthroplasty are reported to include reduced blood loss , less pain , and shorter hospital stays , which combine to afford a faster recovery1 - 4 . However , other studies have failed to show any significant advantage over the use of st and ard surgical approaches ( Fig. 1)5 - 8 . Reported disadvantages of minimally invasive techniques are the substantial learning curve required and an increased risk of early complications3,9 - 12 . In addition , the long-term outcomes of minimally invasive procedures in terms of implant fixation and longevity remain unproven . Fig. 1 The st and ard direct lateral approach to the hip previously described by Frndak et al.21 is performed with the patient in the lateral decubitus position . ( Printed with permission of Joint Implant Surgeons , Inc. ) There are three basic categories of so-called minimally invasive total hip arthroplasty approaches : an abbreviated incision ( small incision ) , modifications of st and ard approaches with smaller incisions and less soft-tissue dissection ( less invasive ) , and novel approaches that reportedly do not cut muscle ( minimally invasive ) . We have had a broad experience , over the past seven years , with a less invasive modification of the direct lateral approach ( a modified Hardinge approach ) ( Fig. 2 ) . We previously reported less blood loss and a shorter hospital stay in association with this approach13 . Others have argued that the less invasive direct lateral approach does not provide an advantage over the traditional approach5 . Importantly , the soft-tissue dissection still requires removing and repairing the abductor musculature . Fig. 2 The less invasive direct lateral approach is performed with the patient in the lateral decubitus position . This approach employs an abbreviated skin and fascial incision with a limited abductor muscle dissection13 . ( Printed with permission of Joint Implant Surgeons , Inc. ) Several recent reports have The benefits of different surgical approaches for total hip arthroplasty continue to be debated . One hundred patients were prospect ively enrolled and r and omized into 2 groups . One group underwent total hip arthroplasty through a single-incision modified Smith-Peterson approach , whereas the other group  underwent total hip arthroplasty through a direct lateral approach . All patients received the same postoperative protocol . Evaluation included operative time , estimated blood loss , analgesia requirement , transfusions , and length of stay . Functional outcome was assessed preoperatively and postoperatively . Up to 1-year follow-up , the direct anterior group demonstrated significantly better improvement in both the mental and physical health dimensions of Short Form-36 and Western Ontario McMaster Osteoarthritis Index compared with direct lateral approach group . At 2 years , the results in both groups were the same Background The tissue sparing surgery ( TSS ) concept means not only smaller incisions but also less tissue disruption , allowing decreased blood loss and improved function . However , TSS techniques can result in more complications related to the learning curve . The aim of this study was to compare the learning curve of an experienced surgeon with different TSS approaches for total hip replacement ( THR ) from a clinical and surgical point of view , focussing especially on complications related to the use of different geometric stems . Material s and methods Sixty patients scheduled to be operated for a primary THR were enrolled in the study and were r and omly assigned to surgery by one of three different TSS approaches : lateral with mini incision ( group A ) , minimally invasive anterior ( group B ) and minimally invasive antero-lateral ( group C ) . Results from the three TSS groups were compared with a control group of 149 patients ( group D ) . Results Our results reveal significantly reduced blood loss in the TSS groups compared with the control group , with no differences between the TSS groups . We found better early functional scores in the two minimally invasive groups ( anterior and anterolateral ) , and a lower rate of complications with the antero-lateral TSS approach . Conclusion The antero-lateral TSS approach seems to be safer and less dem and ing than st and ard THR surgery , and is suitable for use with different stems Background Newer surgical approaches to THA , such as the direct anterior approach , may influence a patient ’s time to recovery , but it is important to make sure that these approaches do not compromise reconstructive safety or accuracy . Questions / purpose sWe compared the direct anterior approach and conventional posterior approach in terms of ( 1 ) recovery of hip function after primary THA  , ( 2 ) general health outcomes , ( 3 ) operative time and surgical complications , and ( 4 ) accuracy of component placement . Methods In this prospect i ve , comparative , nonr and omized study of 120 patients ( 60 direct anterior THA , 60 posterior THAs )  , we assessed functional recovery using the VAS pain score , timed up and go ( TUG ) test , motor component of the Functional Independence Measure ™ ( M-FIM ™ ) , UCLA activity score , Harris hip score , and patient-maintained subjective milestone diary and general health outcome using SF-12 scores . Operative time , complications , and component placement were also compared . Results Functional recovery was faster in patients with the direct anterior approach on the basis of TUG and M-FIM ™ up to 2 weeks ; no differences were found in terms of the other metrics we used , and no differences were observed between groups beyond 6 weeks . General health outcomes , operative time , and complications were similar between groups . No clinical ly important differences were observed in terms of implant alignment . Conclusions We observed very modest functional advantages early in recovery after direct anterior THA compared to posterior-approach THA . R and omized trials are needed to vali date these findings , and these findings may not generalize well to lower-volume practice setting s or to surgeons earlier in the learning curve of direct anterior THA.Level of Evidence Level II , therapeutic study . See Instructions for Authors for a complete description of levels of evidence Background Minimally invasive surgery ( MIS ) can lead to early recovery , but its postoperative effect is short after total hip arthroplasty for osteoarthritis . Because bipolar hemiarthroplasty ( BHA ) for femoral neck fractures is preferred for elderly patients , early functional recovery may prevent the rapid progression of disuse atrophy , and an MIS surgical approach may improve subsequent hip joint function . Methods MIS-BHA was performed using the direct anterior approach , without muscle or tendon detachment . A total of 83 patients who underwent BHA from April 2007 to February 2009 were assigned to MIS-BHA or conventional BHA . Selection of patients for MIS-BHA was not r and omized . Hip joint function was evaluated with the Hospital for Special Surgery ( HSS ) system at 1 month and 1 year after surgery . Results There were no significant differences in age , sex , height , weight , body mass index , time from admission to surgery , or preinjury HSS scores between two groups . HSS scores were higher with MIS-BHA ( 24.2 vs. 20.2 ; P = 0.01 ) at 1 month but were similar 1 year after surgery ( 29.9 vs. 27.2 ; P = 0.10 ) . Conclusions The effectiveness of MIS-BHA for femoral neck fracture is limited to the early postoperative period . Therefore , MIS-BHA does not appear to be appropriate for treatment of femoral neck fractures Anterior supine intermuscular total hip arthroplasty ( THA ) performed on a fracture table has been increasingly used for primary THA . Accurate cup placement , low incidence of dislocation , shorter hospital stay , and faster return of function are potential benefits of the technique . However , a high complication rate , particularly during a surgeon 's learning curve , has been reported . A retrospective analysis of 61 consecutive anterior supine intermuscular primary THAs with at least 6-month follow-up was performed . All procedures were performed using the anterior supine intermuscular approach with cementless implants under fluoroscopic guidance on a fracture table . Prospect ively collected data were retrospectively review ed to evaluate the early complication rate and radiographic accuracy of implant placement . Five ( 8.2 % ) intraoperative complications were observed : including 3 trochanteric fractures and 2 calcar fractures , 4 of which required cable fixation during the index procedure . One nondisplaced trochanteric fracture was treated conservatively . One patient sustained an injury of the lateral femoral cutaneous nerve . Postoperative complications included 1 anterior dislocation , 1 infected superficial hematoma , 1 stem subsidence , and 1 loose stem , with the latter 2 presenting as increasing thigh pain postoperatively and requiring stem revision . The overall complication rate was 16.4 % ( 10/61 ) . Overall , 3 patients ( 4 hips ; 6.5 % ) required reoperation . No femoral or sciatic nerve injuries occurred , and no patient was diagnosed with venous thromboembolism . All intraoperative fractures occurred during the first 32 cases , and none during the last 29 cases . A potentially high incidence of complications with the anterior supine intermuscular THA exists during a surgeon 's learning curve in an academic setting Background and purpose There is still conflicting evidence about the true benefit of minimally invasive ( MI ) techniques in total hip replacement ( THR ) . The aim of this prospect i ve study was to evaluate the safeness of a MI approach during the learning curve of a single surgeon . Second , clinical and radiographic results among the  MI THR group were compared with the results using a st and ard transgluteal ( Bauer ) approach . Methods 86 primary unilateral total hip arthroplasties ( THAs ) through a MI , anterior ( Micro-hip ® ) approach were performed by a single senior surgeon ( ES ) , representing a consecutive series of patients after beginning with the MI technique . Cases were compared to a matched cohort of patients who were treated with a st and ard transgluteal ( Bauer ) approach .  Operation time , incision length , perioperative blood loss , haemoglobin level and blood transfusions were monitored . Complications were documented and followed up 1 year postoperatively . The Harris Hip Score ( HHS ) , range of motion , use of analgetics , the Trendelenburg sign , sensibility of the lateral femoral cutaneous nerve and the acetabular/femoral component placement as well as potential heterotopic ossifications were analysed in both the groups after 12 months postoperatively . Results 74 MI THR patients and 60 st and ard THR patients were available for the one year follow-up . Operative time was significantly longer in the MI group , reduction in the haemoglobin level during the first 24 h was significant and the length of skin incision was significantly shorter . No significant differences were found for HHS , range of motion , use of analgetics , the Trendelenburg sign , and the acetabular/femoral component placement , heterotopic ossifications and intra- and postoperative complications . Sensibility of the lateral femoral cutaneous nerve was affected in three patients in the MI group . Radiographic evaluation revealed no component migration , implant subsidence or radiolucency signs in both the groups . DicussionConsistent with recent meta- analysis we found reduced blood loss , similar clinical /radiographic outcome and similar complication rates compared to st and ard THA . Our study shows , that MI THR is a safe procedure during the learning curve of an experienced surgeon Introduction The direct anterior approach ( DAA ) is generally accepted method for minimal invasive arthroplasty of the hip . As good results for total hip arthroplasty are already published , there is a lack of evidence for the implantation of bipolar hip hemiarthroplasty ( BHH ) in elderly patients with osteoporosis after femoral neck fracture . Material s and methods For hip arthroplasty using a direct anterior approach ( DAA ) in elderly patients with femoral neck fractures , a number of modifications of the original technique are being described . The modified DAA considers in particular the co-morbidity and the bone quality of the geriatric patient population . A consecutive series of 16 hemiarthroplasties using this technique is presented . In all 16 cases , the BHH was implanted in modified DAA technique . Mobility measured by 4-item Barthel Index , pain via visual analogue scale ( VAS ) , duration of surgery , external length of incision and blood loss were evaluated . Results There was no major operative complication during the procedures . The pain level decreased from 7 ( preoperatively ) to 0 at postoperative day 40 . The Barthel Index increased from 5 at first postoperative day to 40 at day 40 . Early postoperative mobilisation is efficiently accelerated . Mean operating time was 71 min ; the medium skin incision length was 8 cm . The mean haemoglobin level decreased from 118 g/dl preoperatively to 101 g/dl at first postoperative day . Conclusion The described modifications of the DAA help to implant a BHH gently in elderly patients with increasing risk of complications like iatrogenic fractures , wound or prosthesis infections and haematoma . This will hopefully lead to a faster rehabilitation and lower mortality rate for patients with femoral neck fractures in the future A prospect i ve study including 1764 hips has been carried out to evaluate the frequency of dislocation while using the Hueter 
    Output:
    
agent
Thus , while DAA hip arthroplasty can be successfully performed , it is not without complications .
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Benefits of a direct anterior approach ( DAA ) versus a posterior-lateral ( PA ) approach to THA were assessed in a single-surgeon , IRB-approved , prospect i ve , r and omized clinical study . Subjects ( 43 DAA and 44 PA ) were evaluated at 6 weeks , and 3 , 6 and 12 months . The primary end point was ability to climb stairs normally and walk unlimited at each time point . Secondary end points included assessment by several outcome instruments . DAA subjects performed better during the immediate post-operative period ; they had lower VAS pain scores on the first post-operative day , more subjects climbing stairs normally and walking unlimited at 6 weeks , and higher HOOS Symptoms scores at 3 months . There were no significant differences between groups at later time points . Findings confirm previous reports of benefits of DAA versus PA in early post-operative phases The advantages of minimally invasive surgical approaches for total hip arthroplasty are reported to include reduced blood loss , less pain , and shorter hospital stays , which combine to afford a faster recovery1 - 4 . However , other studies have failed to show any significant advantage over the use of st and ard surgical approaches ( Fig. 1)5 - 8 . Reported disadvantages of minimally invasive techniques are the substantial learning curve required and an increased risk of early complications3,9 - 12 . In addition , the long-term outcomes of minimally invasive procedures in terms of implant fixation and longevity remain unproven . Fig. 1 The st and ard direct lateral approach to the hip previously described by Frndak et al.21 is performed with the patient in the lateral decubitus position . ( Printed with permission of Joint Implant Surgeons , Inc. ) There are three basic categories of so-called minimally invasive total hip arthroplasty approaches : an abbreviated incision ( small incision ) , modifications of st and ard approaches with smaller incisions and less soft-tissue dissection ( less invasive ) , and novel approaches that reportedly do not cut muscle ( minimally invasive ) . We have had a broad experience , over the past seven years , with a less invasive modification of the direct lateral approach ( a modified Hardinge approach ) ( Fig. 2 ) . We previously reported less blood loss and a shorter hospital stay in association with this approach13 . Others have argued that the less invasive direct lateral approach does not provide an advantage over the traditional approach5 . Importantly , the soft-tissue dissection still requires removing and repairing the abductor musculature . Fig. 2 The less invasive direct lateral approach is performed with the patient in the lateral decubitus position . This approach employs an abbreviated skin and fascial incision with a limited abductor muscle dissection13 . ( Printed with permission of Joint Implant Surgeons , Inc. ) Several recent reports have The benefits of different surgical approaches for total hip arthroplasty continue to be debated . One hundred patients were prospect ively enrolled and r and omized into 2 groups . One group underwent total hip arthroplasty through a single-incision modified Smith-Peterson approach , whereas the other group  underwent total hip arthroplasty through a direct lateral approach . All patients received the same postoperative protocol . Evaluation included operative time , estimated blood loss , analgesia requirement , transfusions , and length of stay . Functional outcome was assessed preoperatively and postoperatively . Up to 1-year follow-up , the direct anterior group demonstrated significantly better improvement in both the mental and physical health dimensions of Short Form-36 and Western Ontario McMaster Osteoarthritis Index compared with direct lateral approach group . At 2 years , the results in both groups were the same Background The tissue sparing surgery ( TSS ) concept means not only smaller incisions but also less tissue disruption , allowing decreased blood loss and improved function . However , TSS techniques can result in more complications related to the learning curve . The aim of this study was to compare the learning curve of an experienced surgeon with different TSS approaches for total hip replacement ( THR ) from a clinical and surgical point of view , focussing especially on complications related to the use of different geometric stems . Material s and methods Sixty patients scheduled to be operated for a primary THR were enrolled in the study and were r and omly assigned to surgery by one of three different TSS approaches : lateral with mini incision ( group A ) , minimally invasive anterior ( group B ) and minimally invasive antero-lateral ( group C ) . Results from the three TSS groups were compared with a control group of 149 patients ( group D ) . Results Our results reveal significantly reduced blood loss in the TSS groups compared with the control group , with no differences between the TSS groups . We found better early functional scores in the two minimally invasive groups ( anterior and anterolateral ) , and a lower rate of complications with the antero-lateral TSS approach . Conclusion The antero-lateral TSS approach seems to be safer and less dem and ing than st and ard THR surgery , and is suitable for use with different stems Background Newer surgical approaches to THA , such as the direct anterior approach , may influence a patient ’s time to recovery , but it is important to make sure that these approaches do not compromise reconstructive safety or accuracy . Questions / purpose sWe compared the direct anterior approach and conventional posterior approach in terms of ( 1 ) recovery of hip function after primary THA  , ( 2 ) general health outcomes , ( 3 ) operative time and surgical complications , and ( 4 ) accuracy of component placement . Methods In this prospect i ve , comparative , nonr and omized study of 120 patients ( 60 direct anterior THA , 60 posterior THAs )  , we assessed functional recovery using the VAS pain score , timed up and go ( TUG ) test , motor component of the Functional Independence Measure ™ ( M-FIM ™ ) , UCLA activity score , Harris hip score , and patient-maintained subjective milestone diary and general health outcome using SF-12 scores . Operative time , complications , and component placement were also compared . Results Functional recovery was faster in patients with the direct anterior approach on the basis of TUG and M-FIM ™ up to 2 weeks ; no differences were found in terms of the other metrics we used , and no differences were observed between groups beyond 6 weeks . General health outcomes , operative time , and complications were similar between groups . No clinical ly important differences were observed in terms of implant alignment . Conclusions We observed very modest functional advantages early in recovery after direct anterior THA compared to posterior-approach THA . R and omized trials are needed to vali date these findings , and these findings may not generalize well to lower-volume practice setting s or to surgeons earlier in the learning curve of direct anterior THA.Level of Evidence Level II , therapeutic study . See Instructions for Authors for a complete description of levels of evidence Background Minimally invasive surgery ( MIS ) can lead to early recovery , but its postoperative effect is short after total hip arthroplasty for osteoarthritis . Because bipolar hemiarthroplasty ( BHA ) for femoral neck fractures is preferred for elderly patients , early functional recovery may prevent the rapid progression of disuse atrophy , and an MIS surgical approach may improve subsequent hip joint function . Methods MIS-BHA was performed using the direct anterior approach , without muscle or tendon detachment . A total of 83 patients who underwent BHA from April 2007 to February 2009 were assigned to MIS-BHA or conventional BHA . Selection of patients for MIS-BHA was not r and omized . Hip joint function was evaluated with the Hospital for Special Surgery ( HSS ) system at 1 month and 1 year after surgery . Results There were no significant differences in age , sex , height , weight , body mass index , time from admission to surgery , or preinjury HSS scores between two groups . HSS scores were higher with MIS-BHA ( 24.2 vs. 20.2 ; P = 0.01 ) at 1 month but were similar 1 year after surgery ( 29.9 vs. 27.2 ; P = 0.10 ) . Conclusions The effectiveness of MIS-BHA for femoral neck fracture is limited to the early postoperative period . Therefore , MIS-BHA does not appear to be appropriate for treatment of femoral neck fractures Anterior supine intermuscular total hip arthroplasty ( THA ) performed on a fracture table has been increasingly used for primary THA . Accurate cup placement , low incidence of dislocation , shorter hospital stay , and faster return of function are potential benefits of the technique . However , a high complication rate , particularly during a surgeon 's learning curve , has been reported . A retrospective analysis of 61 consecutive anterior supine intermuscular primary THAs with at least 6-month follow-up was performed . All procedures were performed using the anterior supine intermuscular approach with cementless implants under fluoroscopic guidance on a fracture table . Prospect ively collected data were retrospectively review ed to evaluate the early complication rate and radiographic accuracy of implant placement . Five ( 8.2 % ) intraoperative complications were observed : including 3 trochanteric fractures and 2 calcar fractures , 4 of which required cable fixation during the index procedure . One nondisplaced trochanteric fracture was treated conservatively . One patient sustained an injury of the lateral femoral cutaneous nerve . Postoperative complications included 1 anterior dislocation , 1 infected superficial hematoma , 1 stem subsidence , and 1 loose stem , with the latter 2 presenting as increasing thigh pain postoperatively and requiring stem revision . The overall complication rate was 16.4 % ( 10/61 ) . Overall , 3 patients ( 4 hips ; 6.5 % ) required reoperation . No femoral or sciatic nerve injuries occurred , and no patient was diagnosed with venous thromboembolism . All intraoperative fractures occurred during the first 32 cases , and none during the last 29 cases . A potentially high incidence of complications with the anterior supine intermuscular THA exists during a surgeon 's learning curve in an academic setting Background and purpose There is still conflicting evidence about the true benefit of minimally invasive ( MI ) techniques in total hip replacement ( THR ) . The aim of this prospect i ve study was to evaluate the safeness of a MI approach during the learning curve of a single surgeon . Second , clinical and radiographic results among the  MI THR group were compared with the results using a st and ard transgluteal ( Bauer ) approach . Methods 86 primary unilateral total hip arthroplasties ( THAs ) through a MI , anterior ( Micro-hip ® ) approach were performed by a single senior surgeon ( ES ) , representing a consecutive series of patients after beginning with the MI technique . Cases were compared to a matched cohort of patients who were treated with a st and ard transgluteal ( Bauer ) approach .  Operation time , incision length , perioperative blood loss , haemoglobin level and blood transfusions were monitored . Complications were documented and followed up 1 year postoperatively . The Harris Hip Score ( HHS ) , range of motion , use of analgetics , the Trendelenburg sign , sensibility of the lateral femoral cutaneous nerve and the acetabular/femoral component placement as well as potential heterotopic ossifications were analysed in both the groups after 12 months postoperatively . Results 74 MI THR patients and 60 st and ard THR patients were available for the one year follow-up . Operative time was significantly longer in the MI group , reduction in the haemoglobin level during the first 24 h was significant and the length of skin incision was significantly shorter . No significant differences were found for HHS , range of motion , use of analgetics , the Trendelenburg sign , and the acetabular/femoral component placement , heterotopic ossifications and intra- and postoperative complications . Sensibility of the lateral femoral cutaneous nerve was affected in three patients in the MI group . Radiographic evaluation revealed no component migration , implant subsidence or radiolucency signs in both the groups . DicussionConsistent with recent meta- analysis we found reduced blood loss , similar clinical /radiographic outcome and similar complication rates compared to st and ard THA . Our study shows , that MI THR is a safe procedure during the learning curve of an experienced surgeon Introduction The direct anterior approach ( DAA ) is generally accepted method for minimal invasive arthroplasty of the hip . As good results for total hip arthroplasty are already published , there is a lack of evidence for the implantation of bipolar hip hemiarthroplasty ( BHH ) in elderly patients with osteoporosis after femoral neck fracture . Material s and methods For hip arthroplasty using a direct anterior approach ( DAA ) in elderly patients with femoral neck fractures , a number of modifications of the original technique are being described . The modified DAA considers in particular the co-morbidity and the bone quality of the geriatric patient population . A consecutive series of 16 hemiarthroplasties using this technique is presented . In all 16 cases , the BHH was implanted in modified DAA technique . Mobility measured by 4-item Barthel Index , pain via visual analogue scale ( VAS ) , duration of surgery , external length of incision and blood loss were evaluated . Results There was no major operative complication during the procedures . The pain level decreased from 7 ( preoperatively ) to 0 at postoperative day 40 . The Barthel Index increased from 5 at first postoperative day to 40 at day 40 . Early postoperative mobilisation is efficiently accelerated . Mean operating time was 71 min ; the medium skin incision length was 8 cm . The mean haemoglobin level decreased from 118 g/dl preoperatively to 101 g/dl at first postoperative day . Conclusion The described modifications of the DAA help to implant a BHH gently in elderly patients with increasing risk of complications like iatrogenic fractures , wound or prosthesis infections and haematoma . This will hopefully lead to a faster rehabilitation and lower mortality rate for patients with femoral neck fractures in the future A prospect i ve study including 1764 hips has been carried out to evaluate the frequency of dislocation while using the Hueter 
    Output:
    