There were no significant differences regarding the biomechanical axis or frontal femoral and individual tibial component alignment .
Conclusion This systematic review and meta- analysis demonstrate that alignment with MRI-based PSI is at least as good as , if not better than , that with CT-based PSI .
Purpose Patient-specific instruments ( PSIs ) are already in relatively common use , and their post-operative radiographic results are equal to those for total knee arthroplasty ( TKA ) with conventional instrumentation .
PSI use requires a preoperative MRI scan , CT scan , or a combination of MRI and a long-leg st and ing radiograph .
However , there is no consensus as to which of these modalities , MRI or CT , is the preferred imaging modality when performing TKA with PSIs .
A radiological analysis of the difference between MRI- and CT-based patient-specific matched guides for total knee arthroplasty from the same manufacturer: a randomised controlled trial.
AIMS This prospect i ve r and omised controlled trial was design ed to evaluate the outcome of both the MRI- and CT-based patient-specific matched guides ( PSG ) from the same manufacturer . PATIENTS AND METHODS A total of 137 knees in 137 patients ( 50 men , 87 women ) were included , 67 in the MRI- and 70 in the CT-based PSG group . Their mean age was 68.4 years ( 47.0 to 88.9 ) . Outcome was expressed as the biomechanical limb alignment ( centre hip-knee-ankle : HKA-axis ) achieved post-operatively , the position of the individual components within 3 ° of the pre-operatively planned alignment , correct planned implant size and operative data ( e.g. operating time and blood loss ) . RESULTS The patient demographics ( e.g. age , body mass index ) , correct planned implant size and operative data were not significantly different between the two groups . The proportion of outliers in the coronal and sagittal plane ranged from 0 % to 21 % in both groups . Only the number of outliers for the posterior slope of the tibial component showed a significant difference ( p = 0.004 ) with more outliers in the CT group ( n = 9 , 13 % ) than in the MRI group ( 0 % ) . CONCLUSION The post-operative HKA-axis was comparable in the MRI- and CT-based PSGs , but there were significantly more outliers for the posterior slope in the CT-based PSGs . TAKE HOME MESSAGE Alignment with MRI-based PSG is at least as good as , if not better , than that of the CT-based PSG , and is the preferred imaging modality when performing TKA with use of PSG . Cite this article : Bone Joint J 2016;98-B:786 - 92
There were no significant differences regarding the biomechanical axis or frontal femoral and individual tibial component alignment .
Conclusion This systematic review and meta- analysis demonstrate that alignment with MRI-based PSI is at least as good as , if not better than , that with CT-based PSI .
Purpose Patient-specific instruments ( PSIs ) are already in relatively common use , and their post-operative radiographic results are equal to those for total knee arthroplasty ( TKA ) with conventional instrumentation .
PSI use requires a preoperative MRI scan , CT scan , or a combination of MRI and a long-leg st and ing radiograph .
However , there is no consensus as to which of these modalities , MRI or CT , is the preferred imaging modality when performing TKA with PSIs .