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 .
Accuracy of CT-based patient-specific guides for total knee arthroplasty in patients with post-traumatic osteoarthritis
Abstract Published clinical trials who studied the accuracy of patient-specific guides ( PSG ) for total knee arthroplasty exclude patients with articular deformity of the knee joint . We prospect ively analysed a series of 30 patients with post-traumatic osteoarthritis of the knee joint with use of PSG . At 1 year post-operative , the achieved biomechanical ( HKA ) axis and varus/valgus of the femur and tibia components were measured on anterior – posterior ( AP ) long-st and ing weight-bearing radiographs . Flexion/extension of the femoral and AP slope of the tibia component was measured on st and ard lateral radiographs . Percentages > 3 ° deviation of the pre-operative planned HKA axis and individual implant components were considered as outliers . Approved and used implant size , median blood loss ( ml ) and operation time ( min ) were obtained from the operation records . Pre- and 1-year post-operative patient-reported outcome measures ( PROMs ) were performed . Eighty-three per cent of the patients had a HKA axis restored <3 ° of the pre-operative planned alignment . Varus/valgus outliers were 0.0 and 6.7 % for the femoral and tibial components , respectively . Percentages of outliers of flexion/extension were 36.7 % for the femoral component and 10.0 % for the AP slope of the tibial component . Median blood loss was 300 ml ( 50–700 ) , while operation time was 67 min ( 44–144 ) . In 20 % of all cases , the approved implant size was changed into one size smaller . One-year post-operative PROMs improved significantly . We conclude that the accuracy of CT-based PSG is not impaired in patients with post-traumatic osteoarthritis and this modality can restore biomechanical limb alignment
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 .