Infection rate of VEPTR©-Implants in children with severe spinal and thoracic deformitiesResearch Project | 01.10.2009 - 30.09.2011 Background: Spinal and thoracic deformities in children can be treated with vertical expandable prosthetic titanium ribs (VEPTR©, Synthes GmbH®) to stimulate thoracic and spinal growth. With these implants children s symptoms and conditions can be slowed, halted or even reversed. Because of the dynamic character of the deformity and the growth of the children, the implants have to be lengthened about every half a year. With each operation there is a small risk of infection, which might increase with number of previous surgeries. Implant associated infections are often not clinical apparent and only found in microbiological analysis. To objectify the infection rate, identify potential precursors of infections and the relevance of asymptomatic infections in children with these implants a prospective study is conducted. Hypothesis: Patients with VEPTR©-implants have asymptomatic implant-associated infections. Objective: To objectify the infection rate, we will analyze, during lengthening operation, removed implant-parts microbiological. Design: Prospective case-control study. Study population: We will prospectively include all patients who undergo lengthening operation after VEPTR©-Implantation at the University Children´s Hospital Basel (UKBB). Patients will be excluded if obvious contamination of explanted components occurred in the operation room. It is expected that 4 procedures can be included per month in the study. The study may be extended if the desired patient population (>120 procedures) is not reached within the study period. Methods: All patients and the operating surgeon fill out a questionnaire analyzing clinical signs of infection. A blood sample analyzed for CRP and white blood count is taken prior to operation during anesthesia. All anyway removed implant parts are transported to a microbiology laboratory in a sterile container and treated by sonication. The resulting sonicate fluid will be used for microbial detection by culture and molecular techniques. For potentially later histologic work up, tissue probes are taken and stored in Formalin. The infection rate will be quantified and the microbiological results will be related to clinical findings, laboratory data, operation kind and numbers. Further on the germ spectrum will be analyzed. Hypothesis: We anticipate that the total infection rate lies about 5-10% and increases with number of previous surgeries. Significance: We anticipate that: we will objectify (a) the total infection rate of patients with VEPTR©-implants, and (b) risk factors for infection, especially with low-virulent germs. The natural history (c) of the infection in asymptomatic patients will be followed to analyze its relevance, and (d) treatment regimes can be developed. The public health relevance of this work is significant since these findings: (a) may influence our management of patients with these implants, and (b) may lead to the development of improved implant designs.Members (1) Carol-Claudius HaslerPrincipal InvestigatorResearch Groups Computational Spine Biomechanics Kinderorthopädie (Hasler)
Infection rate of VEPTR©-Implants in children with severe spinal and thoracic deformitiesResearch Project | 01.10.2009 - 30.09.2011
Background: Spinal and thoracic deformities in children can be treated with vertical expandable prosthetic titanium ribs (VEPTR©, Synthes GmbH®) to stimulate thoracic and spinal growth. With these implants children s symptoms and conditions can be slowed, halted or even reversed. Because of the dynamic character of the deformity and the growth of the children, the implants have to be lengthened about every half a year. With each operation there is a small risk of infection, which might increase with number of previous surgeries. Implant associated infections are often not clinical apparent and only found in microbiological analysis. To objectify the infection rate, identify potential precursors of infections and the relevance of asymptomatic infections in children with these implants a prospective study is conducted. Hypothesis: Patients with VEPTR©-implants have asymptomatic implant-associated infections. Objective: To objectify the infection rate, we will analyze, during lengthening operation, removed implant-parts microbiological. Design: Prospective case-control study. Study population: We will prospectively include all patients who undergo lengthening operation after VEPTR©-Implantation at the University Children´s Hospital Basel (UKBB). Patients will be excluded if obvious contamination of explanted components occurred in the operation room. It is expected that 4 procedures can be included per month in the study. The study may be extended if the desired patient population (>120 procedures) is not reached within the study period. Methods: All patients and the operating surgeon fill out a questionnaire analyzing clinical signs of infection. A blood sample analyzed for CRP and white blood count is taken prior to operation during anesthesia. All anyway removed implant parts are transported to a microbiology laboratory in a sterile container and treated by sonication. The resulting sonicate fluid will be used for microbial detection by culture and molecular techniques. For potentially later histologic work up, tissue probes are taken and stored in Formalin. The infection rate will be quantified and the microbiological results will be related to clinical findings, laboratory data, operation kind and numbers. Further on the germ spectrum will be analyzed. Hypothesis: We anticipate that the total infection rate lies about 5-10% and increases with number of previous surgeries. Significance: We anticipate that: we will objectify (a) the total infection rate of patients with VEPTR©-implants, and (b) risk factors for infection, especially with low-virulent germs. The natural history (c) of the infection in asymptomatic patients will be followed to analyze its relevance, and (d) treatment regimes can be developed. The public health relevance of this work is significant since these findings: (a) may influence our management of patients with these implants, and (b) may lead to the development of improved implant designs.
