Assessment of the antero-posterior and rotational stability of the anterior cruciate ligament analogue in a guided motion bi-cruciate stabilized total knee arthroplasty.

Abnormal knee kinematics and sagittal instability after most knee replacements are due in part to deficient anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) function. The guided motion bi-cruciate stabilized knee replacement aspires to stabilize the knee posteriorly and anteriorly by means of a cam-post mechanism. This investigation studies the ACL-stabilizing function of that mechanism in early flexion, and 25 knees that had undergone replacement with this implant were studied. Antero-posterior laxity at 15 degrees flexion was adequately restored for 76% (16/21) of the knees (side-to-side difference <3 mm on KT assessment), and 72% (18/25) knees exhibited a positive pivot shift test. The findings of this study suggest excellent early clinical outcomes for this implant, but the goal of replicating ACL function has only been partially achieved.

[Quality assessment indicators of cardiac surgeons' work; the validity of mortality rates]. / Rapportcijfers voor de hartchirurg; validiteit van waargenomen verschillen in sterfte.

OBJECTIVE: To determine the possibility of comparing the mortality rates of patients operated by different heart surgeons with each other. DESIGN: Retrospective cohort study. SETTING: Academic Medical Centre, Amsterdam, the Netherlands. PATIENTS AND METHODS: Clinical information, operation data and follow-up data on 783 patients who had undergone cardiac valve replacement, were collected from the clinical records. Aortic valve replacement had been performed in 446 patients (1979-1986) and mitral valve replacement in 337 patients (1980-1990). RESULTS: The one-year mortality rate was higher among patients operated on by heart surgeon A than among patients operated on by the other heart surgeons from the same team, viz. 16.4% and 9.5%, respectively, an absolute difference of 6.9%. The 95% confidence interval of the difference was 1.7-12.9. However, it was also found that the risk profiles of these patients of surgeon A differed from those of the other patients. After multivariate correction for this difference in risk profile, the difference in mortality was no longer statistically significant. CONCLUSION: The differences in mortality observed in our study could not be attributed to difference in quality of the heart surgeons, but were related with the risk profiles of the patients operated by one of them. Thorough analysis with correction for risks is necessary for the assessment of the quality of care, if the conclusions are not to be misleading.

Single-institution effectiveness assessment of open-heart surgery in octogenarians.

OBJECTIVE: To determine short- and long-term outcome of open-heart surgery in octogenarians. METHODS: We reviewed the medical charts of 130 consecutive octogenarians undergoing open-heart surgery. Patients with significant comorbidity were excluded from the study. The effect of cardiac and operative risk factors on mortality and morbidity was evaluated. General practitioners and cardiologists were contacted in order to obtain information on the patients' current medical and functional status. RESULTS: Operative mortality for valve replacement (VR) and coronary artery bypass grafting (CABG) was 11.5%. Four-year survival was 73.5% with 75.9% still living independently. The relative risk for operative mortality was 4.3 in case of extracorporeal bypass time exceeding 95 min and 3.6 in case of significant left main stem disease. The risk of late death increased 2.5 times at a left ventricular ejection fraction lower than 50%. CONCLUSIONS: Our data match the results of similar studies involving large numbers of patients. When a multicenter data bank is missing, the evaluation of a relatively small patient group can yield information that may be as useful to patient and physician as information obtained by large studies. Open-heart surgery in octogenarians carries an acceptable mortality risk and its effectiveness in terms of improved quality of life is good.