Aims: 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: 124 procedures of Corin MTK total knee arthroplasty were pre-formed since July1998.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 transepicondylar 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 6–80. Measuring the pre operative angle between the posterior condylar line and the transepi-condylar 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 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.

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.

Objective: To point out the strict rules of surgical technique required for the success of newly applied advanced technology.

Materials: 73 hips in 70 patients, aged 23 to 71 years old, underwent total hip arthroplasty using ceramic bearing surfaces implants. 62 were a primary procedure, and 11 were revision surgery.

Results: One complication of fracture of posterior ace-tabular wall was registered in a patient with ankylosing spondylitis, four early dislocations that were reduced closed, and one case of late postoperative death in a cardiac high-risk patient. No other complications were recorded since the first operation in May 1999. All patients had remarkable pain relief, improved range of motion and improved function.

Discussion: The tribological properties of the ceramic articulating surfaces favors them as the preferred technology for future orthopaedic implants. By reducing wear to a minimum the choice of ceramics seems to be justified. The main concern is fragility versus toughness. We have formulated ten rules of proper surgical technique concerning: accurate fit of the components, accurate orientation of the components, stability of the joints, adequate tissue tension, caring for debris and prevention of metal transfer due to ceramic-metal touch.

Conclusions: While our clinical experience is still short term, it appears that applying a rigorous and uncompromising surgical technique with ceramic bearing surfaces is essential for the clinical success of this potent bio-material.

Based on our experience, our recommendations are that:

Ceramic bearing surfaces T.H.A.-s should be performed in specialized centers.

Objective: To present our innovative surgical technique that simultaneously provides optimal femorotibial tracking and patellofemoral tracking in total knee arthroplasty.

Material and methods: A total of 127 patients underwent total knee arthroplasty using new criteria for femoral, tibial and patellar preparation and placement of their respective components. The technique consisted of intraoperative determination of the rotation of the femoral and tibial components, lateralization of the femoral and tibial components and medialization of the patellar component, thus reducing the Q-angle. It provided excellent tracking of the tibiofemoral and patellofemoral joints without retinacular release.

Results: At a follow up of up to 3 years, 90% of patients gained up to 120 degrees of motion within first 6 months. Rest pain score [10-0] improved from 5.2 to 0.8. Activity pain score [10-0] improved from 9.0 to 2.0. Stair climbing [0–10] improved from 2.8 to 7.1. Walking score improved from 3.2 to 7.3. ADL function improved from 4.3 to 7.1. Our complications included 1 case of postoperative traumatic fracture of the patella, that healed spontaneously, 1 deep infection which responded well to open lavage, and 6 cases of delayed wound healing that required secondary closure. One patient died of unrelated cause. No fracture, loosening, component failure or instability was recorded. None of the implants required removal.

Conclusion: Implementation of our 10 rules concept of surgical technique gave early excellent results, and we recommend it as a technique universally applicable in total knee arthroplasty.