Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA , with no difference in complication rates and risk for acetabular outliers .
Strong evidence exists that there is no difference in physical functioning , measured either by question naires or by gait analysis .
Moderate evidence was found for a shorter length of hospital stay after MIS THA .
Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period , but that effect diminished after three months postoperatively .
Strong evidence was found for an increase in operative time for CAS THA , and limited evidence was found for a decrease in intraoperative blood loss .
Furthermore , strong evidence was found for no difference in complication rates , as well as for a significantly lower risk for acetabular outliers .
Conclusions The results indicate that MIS THA is a safe surgical procedure , without increases in operative time , blood loss , operative complication rates and component malposition rates .
However , the beneficial effect of MIS THA on functional recovery has to be proven .
The results also indicate that CAS THA , though result ing in an increase in operative time , may have a positive effect on operative blood loss and operative complication rates .
More importantly , the use of CAS results in better positioning of acetabular component of the prosthesis
Background Both minimally invasive surgery ( MIS ) and computer-assisted surgery ( CAS ) for total hip arthroplasty ( THA ) have gained popularity in recent years .
We conducted a qualitative and systematic review to assess the effectiveness of MIS , CAS and computer-assisted MIS for THA .
Greater accuracy in positioning of the acetabular cup by using an image-free navigation system
In a prospect i ve and r and omised clinical study ,  acetabular cups were implanted free-h and  ( control group n=22 )  or with computer assistance using an image-free navigation system ( study group n=23 ) . The cup position was determined postoperatively on pelvic CT . An average inclination of 42.3 ° ( range : 30 ° –53 ° ; SD±7.0 ° ) and an average anteversion of 24.0 ° ( range : −3 ° to 51 ° ; SD±15.0 ° ) were found in the control group , and an average inclination of 45.0 ° ( ranage : 40 ° –50 ° ; SD±2.8 ° ) and an average anteversion of 14.4 ° ( range : 5 ° –25 ° ; SS±5.0 ° ) in the computer-assisted study group . The deviations from the desired cup position ( 45 ° inclination , 15 ° anteversion ) were significantly lower in the computer-assisted study group ( p<0.001 each ) . While only 11/22 of the cups in the control group were within the Lewinnek safe zone , 21/23 of the cups in the study group were placed in this target region (p=0.003).RésuméDans un étude clinique prospect i ve et r and omisé , les cupules acétabulaires ont été implantées de façon habituelle ( n=22 ; groupe témoin ) ou avec assistance d’un ordinateur qui utilise un système de navigation image — libre ( n=23 ; groupe d’étude ) . La place de la cupule a été déterminée après l’opération sur un scanner pelvien . Une inclinaison moyenne de 42,3 ° ( 30 ° à 53 ° ; ±7.0 ° ) et une antéversion moyenne de 24,0 ° ( −3 ° à 51 ° ; ±15.0 ° ) ont été trouvées dans le groupe témoin et une inclinaison moyenne de 45,0 ° ( 40 ° à 50 ° ; ±2.8 ° ) et une antéversion moyenne de 14,4 ° ( 5 ° à 25 ° ; ±5.0 ° ) dans le groupe de l’étude assistée par ordinateur . Les déviations par rapport à la position désirée de la cupule ( 45 ° d’inclinaison , 15 ° d’antéversion ) étaient notablement inférieures dans le groupe de l’étude assistée par ordinateur ( p<0.001 chacun ) . Alors que seulement 11 des 22 cupules du groupe témoin étaient dans la zone sûre de Lewinnek , 21 des 23 cupules du groupe d’étude ont été placées dans cette région cible ( p=0.003 )
Strong evidence was found for a decrease in operative time and intraoperative blood loss for MIS THA , with no difference in complication rates and risk for acetabular outliers .
Strong evidence exists that there is no difference in physical functioning , measured either by question naires or by gait analysis .
Moderate evidence was found for a shorter length of hospital stay after MIS THA .
Conflicting evidence was found for a positive effect of MIS THA on pain in the early postoperative period , but that effect diminished after three months postoperatively .
Strong evidence was found for an increase in operative time for CAS THA , and limited evidence was found for a decrease in intraoperative blood loss .
Furthermore , strong evidence was found for no difference in complication rates , as well as for a significantly lower risk for acetabular outliers .
Conclusions The results indicate that MIS THA is a safe surgical procedure , without increases in operative time , blood loss , operative complication rates and component malposition rates .
However , the beneficial effect of MIS THA on functional recovery has to be proven .
The results also indicate that CAS THA , though result ing in an increase in operative time , may have a positive effect on operative blood loss and operative complication rates .
More importantly , the use of CAS results in better positioning of acetabular component of the prosthesis
Background Both minimally invasive surgery ( MIS ) and computer-assisted surgery ( CAS ) for total hip arthroplasty ( THA ) have gained popularity in recent years .
We conducted a qualitative and systematic review to assess the effectiveness of MIS , CAS and computer-assisted MIS for THA .