The majority of adverse events associated with CNTKA were minor and comparable with those seen with conventional TKA .
Clinical outcomes were comparable between the two techniques , with longer-term follow-up suggesting that CNTKA provided no benefit over conventional TKA in terms of sustained functional improvements .
At present , it is unclear whether the significant improvements shown in radiological outcomes after CNTKA translate to measurable clinical benefits .
BACKGROUND Conventional total knee arthroplasty ( TKA ) and the more recently available computer-navigated total knee arthroplasty ( CNTKA ) use alternative methods to achieve correct limb alignment .
This systematic review was undertaken to assess the safety and effectiveness of CNTKA compared with conventional TKA .
Computer-assisted techniques versus conventional guides for component alignment in total knee arthroplasty: a randomized controlled trial.
BACKGROUND Optimal alignment of the prosthesis in total knee arthroplasty results in improved patient outcomes . The goal of this study was to determine the most accurate technique for component alignment in total knee arthroplasty by comparing computer-assisted surgery with two conventional techniques involving use of an intramedullary guide for the femur and either an intramedullary or an extramedullary guide for the tibia . METHODS One hundred and seven patients were r and omized prior to surgery to one of three arms :  computer-assisted surgery for both the femur and the tibia ( the computer-assisted surgery group ) , intramedullary guides for both the femur and the tibia ( the intramedullary guide group ) , and an intramedullary guide for the femur and an extramedullary guide for the tibia ( the extramedullary guide group ) . Measurements of alignment on hip-to-ankle radiographs and computed tomography ( CT ) scans made three months after surgery were evaluated . The operative times and complications were compared among the three groups . RESULTS The coronal tibiofemoral angle demonstrated , on average , less malalignment in the computer-assisted surgery group ( 1.91 ° ) than in the extramedullary ( 3.22 ° ) and intramedullary ( 2.59 ° ) groups ( p = 0.007 ) . The coronal tibiofemoral angle was > 3 ° of varus or valgus deviation in 19 % ( seven ) of the thirty-six patients treated with computer-assisted surgery compared with 38 % ( thirteen ) of the thirty-four in the extramedullary guide group and 36 % ( thirteen ) of the thirty-six in the intramedullary guide group ( p = 0.022 ) . The increase in accuracy with computer-assisted surgery came at a cost of increased operative time . The operative time for the computer-assisted surgery group averaged 107 minutes compared with eighty-three and eighty minutes , respectively , for the surgery with the extramedullary and intramedullary guides ( p < 0.0001 ) . There was no significant difference in any of the outcomes between the intramedullary and extramedullary guide groups . CONCLUSIONS This study provides evidence that the implant alignment with computer-assisted total knee arthroplasty , as measured with radiography and computed tomography , is significantly improved compared with that associated with conventional surgery with intramedullary or extramedullary guides . This finding adds to the body of evidence showing an improved radiographic outcome with computer-assisted surgery compared with that following conventional total knee arthroplasty
The majority of adverse events associated with CNTKA were minor and comparable with those seen with conventional TKA .
Clinical outcomes were comparable between the two techniques , with longer-term follow-up suggesting that CNTKA provided no benefit over conventional TKA in terms of sustained functional improvements .
At present , it is unclear whether the significant improvements shown in radiological outcomes after CNTKA translate to measurable clinical benefits .
BACKGROUND Conventional total knee arthroplasty ( TKA ) and the more recently available computer-navigated total knee arthroplasty ( CNTKA ) use alternative methods to achieve correct limb alignment .
This systematic review was undertaken to assess the safety and effectiveness of CNTKA compared with conventional TKA .