To identify the presence of the Adamkiewica artery before operating spine tumor patients and avoid neurological complications as well as evaluate the impact on surgical strategy.

All tumor patients requiring spinal fixation from Feb 2002 to March 2006 were prospectively enrolled in the study. Included patients either had a primary spine tumor or a spine metastasis. Patients underwent a selective arteriography of the level above, the level below and the level involved by the tumor in order to document any Adamkiewicz artery (AKA).

Eighteen patients were enrolled. Six had a primary tumor and twelve had a metastasis between levels T1 to L3. There were no complications related to the radiological procedure. For ten (55%) of patients, the AKA was identified during the selective arteriogram. In seven of the twelve (58%) metastatic cases the AKA was found adjacent to the involved level. In 60% of cases the AKA was found on the left side. In all cases where the AKA was found, the surgical strategy was modified in order to preserve the AKA. No patients had permanent neurological complications.

The location of the AKA is extremely variable. in more than half our cases, the AKA was found immediately adjacent to the involved level. This could suggest a vascular explanation for the location of tumors in the spine. The vicinity of the AKA to the tumor site may explain why neurological complications are frequent when operating such spine cases.

To prospectively evaluate the accuracy as well as patient outcome of computer-assisted total knee replacement in a multi-centric randomised study.

Two hundred and ninety-five patients in six European centers were randomised between two groups: One hundred and forty-seven in the conventional surgery group and one hundred and forty-eight in the computer assisted surgery. Radiological as well as clinical data (SF-36 and KSS scores) were collected preoperatively as well as six weeks and six months postoperatively. A multilevel mixed-effects linear regression for nested variable with random-effects was used to estimate the effect of the independent variable (type of surgery: conventional surgery vs computer assisted surgery) on each of the dependent variables at six weeks and six months post-operatively.

Mechanical axis was statistically better in the navigation group at six weeks (p=0,01) and six months (p=0,04). Similar results are found for the femoral component at six months (p=0,001). At six months, there were statistically greater improvements in the following SF-36 scales for the computer assisted group: bodily pain (p=0,03), role emotional (p=0,03), mental health (p< 0,001), physical health dimension (p=0,01), mental health dimension (p=0,005) and global SF36 score (p=0,002). While a difference in operating time was noted (p< 10-5), the blood losses where similar for both groups (p=0.8).

Computer assisted surgery improves the accuracy in total knee arthroplasty, especially for the mechanical axis and the femoral component orientation. These improvements result in better quality of life for the patient at six months postoperatively. Level of Evidence: I – High-quality randomised controlled trial with statistically significant difference.