We found moderate to strong evidence that no adverse effects on subsidence and osseous integration of the femoral stem after uncemented THA occur after immediate UWB .
The aim of this systematic review was to find evidence -based support in the literature to allow immediate unrestricted weight bearing after  primary uncemented total hip arthroplasty ( THA ) .
Accelerated rehabilitation programs for THA are becoming increasingly popular to shorten hospital stay and to facilitate rapid restoration of function .
The goals of these rehabilitation programs could be more easily achieved if immediate unrestricted weight bearing ( UWB ) could be allowed after a THA .
So far , however , immediate weight bearing is frequently contraindicated in widely accepted protocol s for uncemented THA due to fear for subsidence and absence of osseous integration of the femoral stem .
Thus , frequently protected weight bearing and restricted activities are still advocated for at least 6 weeks after surgery .
In addition , we analyzed the literature to come to a recommendation on gait pattern and walking aid .
No adverse effects of early weight bearing after uncemented total hip arthroplastyA randomized study of 20 patients
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
We found moderate to strong evidence that no adverse effects on subsidence and osseous integration of the femoral stem after uncemented THA occur after immediate UWB .
The aim of this systematic review was to find evidence -based support in the literature to allow immediate unrestricted weight bearing after  primary uncemented total hip arthroplasty ( THA ) .
Accelerated rehabilitation programs for THA are becoming increasingly popular to shorten hospital stay and to facilitate rapid restoration of function .
The goals of these rehabilitation programs could be more easily achieved if immediate unrestricted weight bearing ( UWB ) could be allowed after a THA .
So far , however , immediate weight bearing is frequently contraindicated in widely accepted protocol s for uncemented THA due to fear for subsidence and absence of osseous integration of the femoral stem .
Thus , frequently protected weight bearing and restricted activities are still advocated for at least 6 weeks after surgery .
In addition , we analyzed the literature to come to a recommendation on gait pattern and walking aid .