Abstract
Purpose: The purpose of this study is to evaluate the efficacy of radiographic and computed tomography pre-operative planning and postoperative results of total knee arthroplasty.
Material and methods: 110 procedures of Corin MTK total knee arthroplasty were performed since July 1998.
A strict radiological and CT evaluation was done prior to and following the surgery and accompanied the clinical evaluation and follow up. A cohort of 32 patients is presented in details regarding the imaging pre-operative planning and the post-operative results.
The radiological data included: 1. Angle of frontal deformity; 2. Angle of instability; 3. Fi-Fc – distance from the tip of the fibular head to the distal part of the lateral femoral condyle; 4. Frontal inclination angle of tibial component; 5. Frontal inclination angle of femoral component; 6. Sagital posterior inclination of tibial component; 7. Sagital posterior inclination angle of the femoral component; 8. The distance from the patella to the knee center of motion.
The computed tomography data included: 1. The actual dimensions of the patella, tibia and femur; 2. The preoperative angle between the posterior condylar line and anterior condylar line; 3. The angle between the posterior condylar line and the trans-epicondylar line; 4. The angle of external rotation of the femoral component; 5. The angle of external rotation of the tibial component; 6. The distance of lateralization of the femoral and tibial components.
Results: The desired value of external rotation of the femoral component was 6–8°. Measuring the pre-operative angle between the posterior condylar line and the trans-epicondylar line helped to determine the degree of external rotation intraoperatively. The mean external rotation of the femoral component in our cohort was 6.73.
Measuring the angle of external rotation of the tibial component preop helped to determine the extent of external rotation of the tibial component intraoperatively.
A significant decrease of the postop Q angle was noticed in all patients.
Conclusion: Radiographic and computed tomography postoperative data reflects the value of the preoperative planning of total knee arthroplasty.
The abstracts were prepared by Orah Naor. Correspondence should be addressed to him at the Israel Orthopaedic Association, PO Box 7845, Haifa 31074, Israel.
