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: Background For total hip arthroplasty ( THA ) , minimally invasive surgery ( MIS ) uses a smaller incision and less muscle dissection than the classic approach ( CLASS ) , and may lead to faster rehabilitation . Questions / purpose sDoes minimally invasive hip arthroplasty result in superior clinical outcomes ? Patients and Methods In this double-blind r and omized controlled trial , 120 consecutive primary noncemented THAs in 120 patients were assigned to one of two groups ( MIS or CLASS ) . The r and omization sequence was stratified for two groups of surgeons , ie , those using a posterolateral approach ( PL-CLASS or PL-MIS ) and those using an anterolateral approach ( AL-CLASS or AL-MIS ) . Length of the incisions was 18 cm for the CLASS procedures . MIS incisions were extended at the skin level to 18 cm at the end of the procedure . The primary end point was the Harris hip score ( HHS ) at 6 weeks postoperatively . Patient-centered question naires were obtained preoperatively and after 6 weeks and 1 year . Results For the patients in the MIS group ( average 7.8 cm incision length ) , statistically significant increased mean HHSs were seen compared with the CLASS group at 6 weeks and 1 year . This difference was small and mainly caused by the favorable results of the PL-MIS . In the MIS group , surgical time was longer . A learning curve was observed based on operation time and complication rate . Although not statistically significant , the perioperative complication rate was rather high in the ( anterolateral ) MIS group . Conclusions The minimal invasive approach in THA did not show a clinical ly relevant superior outcome in the first postoperative year . Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence Introduction Minimally invasive total hip arthroplasty ( THA ) is cl aim ed to be superior to the st and ard technique , due to the potential reduction of soft tissue damage via a smaller and tissue-sparing approach . As a result of the lack of objective evidence of fewer muscle and tendon defects , controversy still remains as to whether minimally invasive total hip arthroplasty truly minimizes muscle and tendon damage . Therefore , the objective was to compare the influence of the surgical approach on abductor muscle trauma and to analyze the relevance to postoperative pain and functional recovery . Material s and methods Between June 2006 and July 2007 , 44 patients with primary hip arthritis were prospect ively included in the study protocol . Patients underwent cementless unilateral total hip arthroplasty either through a minimally invasive anterolateral approach ( ALMI ) ( n = 21 ) or a modified direct lateral approach ( mDL ) ( n = 16 ) . Patients were evaluated clinical ly and underwent MR imaging preoperatively and at 3 and 12 months postoperatively . Clinical assessment contained clinical examination , performance of abduction test and the survey of a function score using the Harris Hip Score , a pain score using a numeric rating scale ( NRS ) of 0–10 , as well as a satisfaction score using an NRS of 1–6 . Additionally , myoglobin and creatine kinase were measured preoperatively , and 6 , 24 and 96 h postoperatively . Evaluation of the MRI images included fatty atrophy ( rating scale 0–4 ) , tendon defects ( present/absent ) and bursal fluid collection of the abductor muscle . Results Muscle and tendon damage occurred in both groups , but more lateral gluteus medius tendon defects [ mDL 3/12mth . : 6 (37%)/4 ( 25 % ) ; ALMI : 3 (14%)/2 ( 9 % ) ] and muscle atrophy in the anterior part of the gluteus medius [ mean-st and ard ( 12 ) : 1.75 ± 1.8 ; mean-MIS ( 12 ) : 0.98 ± 1.1 ] were found in patients with the mDL approach . The clinical outcome was also poorer compared to the ALMI group . Significantly , more Trendelenburg ’s signs were evident and lower clinical scores were achieved in the mDL group . No differences in muscle and tendon damage were found for the gluteus minimus muscle . A higher serum myoglobin concentration was measured 6 and 24 h postoperatively in the mDL group ( 6 h : 403 ± 168 μg/l ; 24 h : 304 ± 182 μg/l ) compared to the ALMI group ( 6 h : 331 ± 143 μg/l ; 24 h : 268 ± 145 μg/l ) . Conclusion Abductor muscle and tendon damage occurred in both approaches , but the gluteus medius muscle can be spared more successfully via the minimally invasive approach and is accompanied by a better clinical outcome . Therefore , going through the intermuscular plane , without any detachment or dissection of muscle and tendons , truly minimizes perioperative soft tissue trauma . Furthermore , MRI emerges as an important imaging modality in the evaluation of muscle trauma in THA BACKGROUND AIMS Evaluation of : 1 . early clinical and radiographic results of  total hip arthroplasty ( THA ) through a st and ard lateral direct approach , 2 . early clinical and radiographic results of THA through a minimal lateral approach , 3 . comparison of the results of THA in these two groups . MATERIAL AND METHODS 120 THAs ( 60 cementless and 60 cemented ) done in 120 patients due to degenerative changes were evaluated prospect ively . 60 THAs were done through a minimal lateral approach and constituted a study group . 60 THAs were done through a direct lateral approach and constituted a control group . The mean age of the 120 patients ( 98 women and 22 men ) was 45 y.o . ( range : 32 - 67 y.o . ) . The duration of follow-up in the study group was from 6 to 12 months ( mean : 8.5 months ) . The duration of follow-up in the control group was from 10 to 16 months ( mean : 10.5 months ) . Mean preoperative functional status of the study group was 44.5 points according to the Harris hip score . Radiographic evaluation of the results was done according to the criteria of the Joint Committee of the Hip Society , AAOS and SICOT . RESULTS 6 months after THA , clinical results were 92 pts in the study group and 88 pts in the control group . Radiographic outcomes were very good in all 120 patients from both arms : there were no differences between the control and study group . The incidence of complications was similar in both groups . CONCLUSIONS Minimally invasive THA demonstrated its value in the treatment of  degenerative changes of the hip joint  with regard to short-term outcomes . The clinical and radiographic outcomes were comparable between the st and ard and minimally invasive approaches . Success with THA using a minimally invasive approach depends on excellent operative technique and experience with st and ard hip approaches rather than on the use of special instruments Minimally invasive total hip arthroplasty  using a short skin incision is a subject of much debate in the literature . The present study estimates the possible minimal length of the exposure in an unselected patient cohort and compares the lateral mini-incision technique and traditional total hip arthroplasty ( THA ) .  One hundred and two patients were divided into three groups according to the type of surgery and length of incision : mini-incision ( less than 10  cm ) was performed in 38 patients ; midi-incision ( 10–14 cm ) in 43 ; and  st and ard-incision ( longer than 14 cm ) in 21 patients . No statistical difference was found with regard to intraoperative and total blood loss , the rate of complications , and postoperative recovery . Significantly decreased body mass index ( BMI ) , shorter operative time , and higher number of hips with malpositioning of the acetabular cup were found in the mini-incision group . These patients , however , experienced less pain in the early postoperative period and were highly satisfied with the cosmetic results . The length of incision was shortened and optimized ( less than 14 cm ) in 82 % of patients , and mini-incision was performed in 38 patients of this unselected cohort . Because of the underst and able dem and of the patients for less invasive intervention , the surgeon should use a smaller but not necessarily mini-incision with minimal soft tissue trauma that still allows him to perform the procedure well , without compromising the type of implants and the otherwise excellent long-term results . R and omized prospect i ve studies are needed to explore the real value of the minimally invasive total hip arthroplasty . RésuméLa chirurgie arthroplastie de la hanche par voie mini invasive est un sujet de débat et de controverse dans la littérature . Cette étude a pour but d’estimer la longueur minimale de la voie d’abord sur une suite de patients non sélectionnés et de comparer la technique de mini incision avec la technique d’incision traditionnelle antérolatérale .  Cent deux patients ont été divisés en trois groupes , en fonction du type de chirurgie et en fonction de la longueur d’incision . Premier groupe : mini incision moins de 10 cm chez 38 patients , deuxième groupe : incision moyenne 10 à 14 cm chez 43 patients et troisième groupe : incision st and ard , supérieure à 14 cm chez 21 patients . Aucune différence statistique n’a été trouvée pour la perte sanguine et sur le taux des complications post-opératoires . Dans le groupe des mini incisions peu de sujets avaient une surcharge pondérale , par contre , il existait un gr and nombre de hanches avec une mal position de la cupule . Ces patients ont cependant présenté moins de douleur dans la période post-opératoire et ont été très satisfaits du résultat cosmétique . La longueur de l’incision dans la chirurgie prothétique de la hanche peut être raccourcie et la longueur optimum peut être de moins de 14 cm chez 82 % des patients . Une mini incision a été réalisé dans cette série , chez 38 patients du fait de la dem and e des patients pour une chirurgie mini invasive , les chirurgiens ont utilisé une petite incision avec un minimum de traumatisme des tissus mous . Cette mini incision doit donc permettre au chirurgien de réaliser son intervention correctement sans compromission sur le type d ’ implants , ni sur la qualité des résultats à long terme . Il n’y a pas besoin pour cela nécessairement d’une mini incision néanmoins des études prospect ives r and omisées doivent être réalisées pour explorer le vrai résultat de la chirurgie arthroplastie par voie mini invasive Patients are inquiring about  mini-incision primary total hip arthroplasty  with increasing frequency . There are no published r and omized controlled trials to substantiate cl aims that the mini-incision direct lateral approach is better than a st and ard approach . The purpose of our study was to review our initial experience with the mini-incision technique through the direct lateral approach , with the intent of implementing a r and omized controlled trial if the approach could be shown as safe and effective . Of importance was determining if there is any difference in component positioning and if there is any difference in intraoperative or postoperative complications between the two groups . We retrospectively compared a consecutive series of 87 primary total hip arthroplasties . Thirty-four total hip arthroplasties were done using a mini-incision direct lateral approach . The mean abduction angle was 45 ° for both groups . The femoral stem alignment was within five degrees of neutral in 97 % of the mini group and 94 % of the st and ard group . There were no dislocations , infections , neurologic or wound complications . There were no differences in medical complications or blood transfusions . A significant decrease was found regarding body mass index , which reflects the bias in patient selection and lack of r and omization . We conclude that it is safe to continue further study with this approach because as there was no increase in complications or component malpositioning . Level of Evidence : Therapeutic study , Level III ( retrospective comparative study ) . See the Guidelines for Authors for a complete description of levels of evidence BACKGROUND Minimally invasive total hip arthroplasty has stirred substantial controversy with regard to whether it provides superior outcomes compared with total hip arthroplasty performed through longer incisions . The orthopaedic literature is deficient in well- design ed scientific studies to support the clinical superiority of this approach . The objective of this study was to compare the results of a single mini-incision approach with those of a st and ard-incision total hip arthroplasty in the early postoperative period . METHODS Two hundred and nineteen patients ( 219 hips ) admitted for unilateral total hip arthroplasty between December 2003 and June 2004 were r and omized to undergo surgery through a short incision of < or=10 cm or a st and ard incision of 16 cm .  All patients were blinded to the size of the incision for the duration of the hospital stay . The anesthetic , analgesic , and postoperative physiotherapy protocol s were st and ardized , with the staff also blinded to the technique used . A single surgeon , who had performed more than 300 short-incision hip replacements prior to the start of this study and who performs an average of 415 primary total hip replacements a year , performed all procedures through a single-incision posterior approach using a cementless cup and cemented stem . RESULTS The two groups were matched for age , grade according to the system of the American Society of Anesthesiologists , and body mass index . No significant difference was detected with respect to postoperative hematocrit , blood transfusion requirements , 
    Output:
    
agent
There was no major difference in the rate of complications .
Conclusions Short-term recovery favors limited incision over st and ard incision THA .
***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: Background For total hip arthroplasty ( THA ) , minimally invasive surgery ( MIS ) uses a smaller incision and less muscle dissection than the classic approach ( CLASS ) , and may lead to faster rehabilitation . Questions / purpose sDoes minimally invasive hip arthroplasty result in superior clinical outcomes ? Patients and Methods In this double-blind r and omized controlled trial , 120 consecutive primary noncemented THAs in 120 patients were assigned to one of two groups ( MIS or CLASS ) . The r and omization sequence was stratified for two groups of surgeons , ie , those using a posterolateral approach ( PL-CLASS or PL-MIS ) and those using an anterolateral approach ( AL-CLASS or AL-MIS ) . Length of the incisions was 18 cm for the CLASS procedures . MIS incisions were extended at the skin level to 18 cm at the end of the procedure . The primary end point was the Harris hip score ( HHS ) at 6 weeks postoperatively . Patient-centered question naires were obtained preoperatively and after 6 weeks and 1 year . Results For the patients in the MIS group ( average 7.8 cm incision length ) , statistically significant increased mean HHSs were seen compared with the CLASS group at 6 weeks and 1 year . This difference was small and mainly caused by the favorable results of the PL-MIS . In the MIS group , surgical time was longer . A learning curve was observed based on operation time and complication rate . Although not statistically significant , the perioperative complication rate was rather high in the ( anterolateral ) MIS group . Conclusions The minimal invasive approach in THA did not show a clinical ly relevant superior outcome in the first postoperative year . Level of Evidence Level I , therapeutic study . See Guidelines for Authors for a complete description of levels of evidence Introduction Minimally invasive total hip arthroplasty ( THA ) is cl aim ed to be superior to the st and ard technique , due to the potential reduction of soft tissue damage via a smaller and tissue-sparing approach . As a result of the lack of objective evidence of fewer muscle and tendon defects , controversy still remains as to whether minimally invasive total hip arthroplasty truly minimizes muscle and tendon damage . Therefore , the objective was to compare the influence of the surgical approach on abductor muscle trauma and to analyze the relevance to postoperative pain and functional recovery . Material s and methods Between June 2006 and July 2007 , 44 patients with primary hip arthritis were prospect ively included in the study protocol . Patients underwent cementless unilateral total hip arthroplasty either through a minimally invasive anterolateral approach ( ALMI ) ( n = 21 ) or a modified direct lateral approach ( mDL ) ( n = 16 ) . Patients were evaluated clinical ly and underwent MR imaging preoperatively and at 3 and 12 months postoperatively . Clinical assessment contained clinical examination , performance of abduction test and the survey of a function score using the Harris Hip Score , a pain score using a numeric rating scale ( NRS ) of 0–10 , as well as a satisfaction score using an NRS of 1–6 . Additionally , myoglobin and creatine kinase were measured preoperatively , and 6 , 24 and 96 h postoperatively . Evaluation of the MRI images included fatty atrophy ( rating scale 0–4 ) , tendon defects ( present/absent ) and bursal fluid collection of the abductor muscle . Results Muscle and tendon damage occurred in both groups , but more lateral gluteus medius tendon defects [ mDL 3/12mth . : 6 (37%)/4 ( 25 % ) ; ALMI : 3 (14%)/2 ( 9 % ) ] and muscle atrophy in the anterior part of the gluteus medius [ mean-st and ard ( 12 ) : 1.75 ± 1.8 ; mean-MIS ( 12 ) : 0.98 ± 1.1 ] were found in patients with the mDL approach . The clinical outcome was also poorer compared to the ALMI group . Significantly , more Trendelenburg ’s signs were evident and lower clinical scores were achieved in the mDL group . No differences in muscle and tendon damage were found for the gluteus minimus muscle . A higher serum myoglobin concentration was measured 6 and 24 h postoperatively in the mDL group ( 6 h : 403 ± 168 μg/l ; 24 h : 304 ± 182 μg/l ) compared to the ALMI group ( 6 h : 331 ± 143 μg/l ; 24 h : 268 ± 145 μg/l ) . Conclusion Abductor muscle and tendon damage occurred in both approaches , but the gluteus medius muscle can be spared more successfully via the minimally invasive approach and is accompanied by a better clinical outcome . Therefore , going through the intermuscular plane , without any detachment or dissection of muscle and tendons , truly minimizes perioperative soft tissue trauma . Furthermore , MRI emerges as an important imaging modality in the evaluation of muscle trauma in THA BACKGROUND AIMS Evaluation of : 1 . early clinical and radiographic results of  total hip arthroplasty ( THA ) through a st and ard lateral direct approach , 2 . early clinical and radiographic results of THA through a minimal lateral approach , 3 . comparison of the results of THA in these two groups . MATERIAL AND METHODS 120 THAs ( 60 cementless and 60 cemented ) done in 120 patients due to degenerative changes were evaluated prospect ively . 60 THAs were done through a minimal lateral approach and constituted a study group . 60 THAs were done through a direct lateral approach and constituted a control group . The mean age of the 120 patients ( 98 women and 22 men ) was 45 y.o . ( range : 32 - 67 y.o . ) . The duration of follow-up in the study group was from 6 to 12 months ( mean : 8.5 months ) . The duration of follow-up in the control group was from 10 to 16 months ( mean : 10.5 months ) . Mean preoperative functional status of the study group was 44.5 points according to the Harris hip score . Radiographic evaluation of the results was done according to the criteria of the Joint Committee of the Hip Society , AAOS and SICOT . RESULTS 6 months after THA , clinical results were 92 pts in the study group and 88 pts in the control group . Radiographic outcomes were very good in all 120 patients from both arms : there were no differences between the control and study group . The incidence of complications was similar in both groups . CONCLUSIONS Minimally invasive THA demonstrated its value in the treatment of  degenerative changes of the hip joint  with regard to short-term outcomes . The clinical and radiographic outcomes were comparable between the st and ard and minimally invasive approaches . Success with THA using a minimally invasive approach depends on excellent operative technique and experience with st and ard hip approaches rather than on the use of special instruments Minimally invasive total hip arthroplasty  using a short skin incision is a subject of much debate in the literature . The present study estimates the possible minimal length of the exposure in an unselected patient cohort and compares the lateral mini-incision technique and traditional total hip arthroplasty ( THA ) .  One hundred and two patients were divided into three groups according to the type of surgery and length of incision : mini-incision ( less than 10  cm ) was performed in 38 patients ; midi-incision ( 10–14 cm ) in 43 ; and  st and ard-incision ( longer than 14 cm ) in 21 patients . No statistical difference was found with regard to intraoperative and total blood loss , the rate of complications , and postoperative recovery . Significantly decreased body mass index ( BMI ) , shorter operative time , and higher number of hips with malpositioning of the acetabular cup were found in the mini-incision group . These patients , however , experienced less pain in the early postoperative period and were highly satisfied with the cosmetic results . The length of incision was shortened and optimized ( less than 14 cm ) in 82 % of patients , and mini-incision was performed in 38 patients of this unselected cohort . Because of the underst and able dem and of the patients for less invasive intervention , the surgeon should use a smaller but not necessarily mini-incision with minimal soft tissue trauma that still allows him to perform the procedure well , without compromising the type of implants and the otherwise excellent long-term results . R and omized prospect i ve studies are needed to explore the real value of the minimally invasive total hip arthroplasty . RésuméLa chirurgie arthroplastie de la hanche par voie mini invasive est un sujet de débat et de controverse dans la littérature . Cette étude a pour but d’estimer la longueur minimale de la voie d’abord sur une suite de patients non sélectionnés et de comparer la technique de mini incision avec la technique d’incision traditionnelle antérolatérale .  Cent deux patients ont été divisés en trois groupes , en fonction du type de chirurgie et en fonction de la longueur d’incision . Premier groupe : mini incision moins de 10 cm chez 38 patients , deuxième groupe : incision moyenne 10 à 14 cm chez 43 patients et troisième groupe : incision st and ard , supérieure à 14 cm chez 21 patients . Aucune différence statistique n’a été trouvée pour la perte sanguine et sur le taux des complications post-opératoires . Dans le groupe des mini incisions peu de sujets avaient une surcharge pondérale , par contre , il existait un gr and nombre de hanches avec une mal position de la cupule . Ces patients ont cependant présenté moins de douleur dans la période post-opératoire et ont été très satisfaits du résultat cosmétique . La longueur de l’incision dans la chirurgie prothétique de la hanche peut être raccourcie et la longueur optimum peut être de moins de 14 cm chez 82 % des patients . Une mini incision a été réalisé dans cette série , chez 38 patients du fait de la dem and e des patients pour une chirurgie mini invasive , les chirurgiens ont utilisé une petite incision avec un minimum de traumatisme des tissus mous . Cette mini incision doit donc permettre au chirurgien de réaliser son intervention correctement sans compromission sur le type d ’ implants , ni sur la qualité des résultats à long terme . Il n’y a pas besoin pour cela nécessairement d’une mini incision néanmoins des études prospect ives r and omisées doivent être réalisées pour explorer le vrai résultat de la chirurgie arthroplastie par voie mini invasive Patients are inquiring about  mini-incision primary total hip arthroplasty  with increasing frequency . There are no published r and omized controlled trials to substantiate cl aims that the mini-incision direct lateral approach is better than a st and ard approach . The purpose of our study was to review our initial experience with the mini-incision technique through the direct lateral approach , with the intent of implementing a r and omized controlled trial if the approach could be shown as safe and effective . Of importance was determining if there is any difference in component positioning and if there is any difference in intraoperative or postoperative complications between the two groups . We retrospectively compared a consecutive series of 87 primary total hip arthroplasties . Thirty-four total hip arthroplasties were done using a mini-incision direct lateral approach . The mean abduction angle was 45 ° for both groups . The femoral stem alignment was within five degrees of neutral in 97 % of the mini group and 94 % of the st and ard group . There were no dislocations , infections , neurologic or wound complications . There were no differences in medical complications or blood transfusions . A significant decrease was found regarding body mass index , which reflects the bias in patient selection and lack of r and omization . We conclude that it is safe to continue further study with this approach because as there was no increase in complications or component malpositioning . Level of Evidence : Therapeutic study , Level III ( retrospective comparative study ) . See the Guidelines for Authors for a complete description of levels of evidence BACKGROUND Minimally invasive total hip arthroplasty has stirred substantial controversy with regard to whether it provides superior outcomes compared with total hip arthroplasty performed through longer incisions . The orthopaedic literature is deficient in well- design ed scientific studies to support the clinical superiority of this approach . The objective of this study was to compare the results of a single mini-incision approach with those of a st and ard-incision total hip arthroplasty in the early postoperative period . METHODS Two hundred and nineteen patients ( 219 hips ) admitted for unilateral total hip arthroplasty between December 2003 and June 2004 were r and omized to undergo surgery through a short incision of < or=10 cm or a st and ard incision of 16 cm .  All patients were blinded to the size of the incision for the duration of the hospital stay . The anesthetic , analgesic , and postoperative physiotherapy protocol s were st and ardized , with the staff also blinded to the technique used . A single surgeon , who had performed more than 300 short-incision hip replacements prior to the start of this study and who performs an average of 415 primary total hip replacements a year , performed all procedures through a single-incision posterior approach using a cementless cup and cemented stem . RESULTS The two groups were matched for age , grade according to the system of the American Society of Anesthesiologists , and body mass index . No significant difference was detected with respect to postoperative hematocrit , blood transfusion requirements , 
    Output:
    