Prospective cohort study.
Objective. To determine the predictors of serum chromium levels after stainless steel posterior spinal instrumentation for adolescent idiopathic scoliosis.
Summary of Background Data. Abnormally elevated serum chromium levels have been detected in patients with adolescent idiopathic scoliosis after stainless steel instrumentation. check details To date, the relationship among serum chromium levels, time of implantation, and implant characteristics (including surface area, rod length, numbers of hooks, screws, and cross connectors)
has not been studied.
Methods. Thirty patients with adolescent idiopathic scoliosis undergoing posterior instrumented spinal arthrodesis using stainless steel implants between 1998 and 2002 were prospectively studied. Serum chromium levels were measured between October 2006 and June 2007. Postoperative radiographs were used to measure rod lengths, number of hooks, screws, cross-connectors, and cables. The surface area of each component and the total surface area for each patient were calculated. Possible associations between serum chromium levels, time of implantation, and implant characteristics were investigated.
Results. Implant exposure, whether expressed in the form of total metal implant surface area, rod length, or number of metal interfaces, was
found to be positively associated with serum chromium levels. Specifically, chromium levels increased by a multiplicative factor of 1.0060 for every additional square centimeter of total metal implant surface area (P = 0.02). In addition, the chromium level was found to decrease by a multiplicative factor of 0.7766 for every PCI-34051 cell line additional year since surgery (P = 0.02).
Conclusion. After adjusting for the number of years since surgery, metal implant exposure is positively associated with elevated serum chromium levels in adolescent idiopathic scoliosis patients with stainless
steel posterior spinal implants. This is the first study to identify statistically significant positive associations between specific spinal implant characteristics (other than corrosion identified by radiographs) and serum chromium levels.”
“Background: Limited information is available on the association between vitamin B-12 status and intake from different dietary Veliparib datasheet sources.
Objective: We investigated the relation of dietary intake of different food items with plasma vitamin B-12 concentrations in the general population.
Design: A cross-sectional, population-based study of 5937 subjects in 2 age groups (47-49 and 71-74 y) from the Hordaland Homocysteine Study in Norway was conducted by using a food-frequency questionnaire and measurements of plasma vitamin B-12 concentrations.
Results: A significant difference in plasma vitamin B-12 concentrations was observed with increasing total vitamin B-12 intake. A plateau was reached at an intake of approximate to 10 mu g/d.