We found that there was no significant benefit from using PS instrumentation in primary knee arthroplasty to aid in the positioning of either the tibial or femoral components .
Furthermore sagittal plane tibial component positioning was worse in the PS than the traditional ST group .
Our results suggest that at present PS instrumentation is not superior to ST instrumentation in primary total knee arthroplasty .
OBJECTIVE The aim of this study was to review the radiological alignment outcomes of patient Specific ( PS ) cutting blocks and St and ard Instrumentation in Primary Total Knee Arthroplasty .
METHODS We hypothesized that the use of PS techniques would significantly improve sagittal , coronal and rotational alignment of the prosthesis on short term .
Coronal alignment correlates with outcome after total knee arthroplasty: five-year follow-up of a randomized controlled trial.
In a prospect i ve r and omized control trial comparing computer-assisted vs conventional total knee arthroplasty  , we previously reported that patients with coronal alignment within 3 ° of neutral had superior international knee society and Short-Form 12 ( SF-12 ) physical scores at 6 weeks , 3 months , 6 months , and 12 months after surgery . Computer-assisted total knee arthroplasty achieved greater accuracy in implant alignment , and this correlated with better knee function and quality of life . At 5 years , 90 of 111 patients assessed in our original study were review ed . Coronal alignment within 3 ° of neutral continued to be correlated with superior International Knee Society and SF-12 scores . Coronal alignment greater than 3 ° was associated with a significant decline in SF-12 mental health scores
We found that there was no significant benefit from using PS instrumentation in primary knee arthroplasty to aid in the positioning of either the tibial or femoral components .
Furthermore sagittal plane tibial component positioning was worse in the PS than the traditional ST group .
Our results suggest that at present PS instrumentation is not superior to ST instrumentation in primary total knee arthroplasty .
OBJECTIVE The aim of this study was to review the radiological alignment outcomes of patient Specific ( PS ) cutting blocks and St and ard Instrumentation in Primary Total Knee Arthroplasty .
METHODS We hypothesized that the use of PS techniques would significantly improve sagittal , coronal and rotational alignment of the prosthesis on short term .