Accuracy of MRI-based Patients Matched Instruments vs Jig-based Instruments in Total Knee Arthroplasty (TKA)

Accuracy of MRI-based Patients Matched Instruments and Jig-based Instruments in Total Knee Arthroplasty

Total knee arthroplasty (TKA) is the common and effective procedure for treatment of end-staged knee osteoarthritis. Postoperative alignment of TKA is one of the important factors which effects on survival of prosthesis. High percentage of misalignment has been reported in conventional technique with using the jig based instruments. Several methods and devices were established to solve this problem. Customized or patient matched instruments were the novel technology that made from magnetic resonance imaging (MRI) of lower limb. With using special software to calculate the alignment axis, it was thought that accurate alignment can be achieved by using this instruments. Therefore, the study aimed to compare the accuracy of MRI based patient matched instruments and jig based instruments in TKA.

Inclusion Criteria:

• Patients diagnosed primary osteoarthritis of knee and planned to undergo total knee arthroplasty

Exclusion Criteria:

• Previous complex surgery of the affected knee
• Metalic implant in the affected lower limb
• Patients who unable or contraindicated to perform MRI
• Extra-articular deformities of the affected lower limb
• Extensive bone loss of distal femur or/and proximal tibia
• More than 30 degrees of knee flexion contracture
• Unable to perform TKA within 12 weeks after MRI