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 .
Responsiveness and clinically important differences for the WOMAC and SF-36 after hip joint replacement.
OBJECTIVES To study responsiveness and establish the minimal clinical ly important differences ( MCID ) and minimal detectable change ( MDC ) in patients undergoing total hip replacement ( THR )  using the Short Form 36 ( SF-36 ) and the Western Ontario and McMaster Universities Osteoarthritis Index ( WOMAC ) . METHODS We conducted a prospect i ve observational study in three public hospitals of all consecutive patients with a diagnosis of hip osteoarthritis ( OA ) on waiting lists to undergo THR .  Patients completed the SF-36 and the  WOMAC  ( subscales transformed to 0 to 100 ) , which measured the health-related quality of life ( HRQoL ) , before intervention and 6 months and 2 years later , and additional transitional questions , which measured the changes in the joint 6 months postoperatively . RESULTS Improvements at 6 months after a THR were between 37 ( stiffness ) and 39 points ( pain ) , depending on the WOMAC domain . The SF-36 domains also showed improvements : physical function ( 31.91 ) , physical role ( 33.71 ) , and bodily pain ( 29.77 ) . From 6 months to 2 years , improvements ranged from 2 to 5 points , except for role physical ( 13.25 ) . A ceiling effect was detected on some WOMAC domains as well as a floor effect on the SF-36 . The MCID ranged from 25.91 ( stiffness ) to 29.26 ( pain ) on the WOMAC and from 10.78 ( physical role ) to 20.40 ( physical function ) on the SF-36 . The MDC ranged from 21.38 ( pain ) to 27.98 ( stiffness ) on the WOMAC and from 18.99 ( physical function ) to 42.05 ( social function ) on the SF-36 . CONCLUSIONS These values indicate expected gains after THR . However , the MCID and MDC values must be viewed cautiously due to the uncertainty of these estimators and should not be considered as absolute thresholds
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 .