Bacterial adhesion to orthopaedic implant materials and a novel oxygen plasma modified PEEK surface.

Despite extensive use of polyetheretherketone (PEEK) in biomedical applications, information about bacterial adhesion to this biomaterial is limited. This study investigated Staphylococcus aureus and Staphylococcus epidermidis adhesion to injection moulded and machined PEEK OPTIMA(®) using a custom-built adhesion chamber with medical grade titanium and Thermanox for comparison. Additionally, bacterial adhesion to a novel oxygen plasma modified PEEK was also investigated in both a pre-operative model in physiological saline, and additionally in a post-operative model in human blood plasma. In the pre-operative model, the rougher machined PEEK had a significantly greater number of adherent bacteria compared to injection moulded PEEK. Bacterial adhesion to titanium and Thermanox was similar. Oxygen plasma surface modification of PEEK did not lead to a significant change in bacterial adhesion in the pre-operative contamination model, despite observed changes in surface characteristics. In the post-operative contamination model, S. aureus adhesion was increased from 5×10(5) CFU cm(-2) to approximately 1.3×10(7) CFU cm(-2) on the modified surfaces due to differential protein adhesion during the conditioning period. However, S. epidermidis adhesion to modified PEEK was less than to unmodified PEEK in the post-operative model. These results illustrate the importance of testing bacterial adhesion of several strains in both a pre-operative and post-operative, clinically relevant bacterial contamination model.

[Deep vein thrombosis associated with osteoarticular infection in two siblings with anti-thrombin III deficiency]. / Trombosis venosa profunda asociada a infección osteoarticular en dos hermanos con deficiencia de antitrombina III.

The development of deep vein thrombosis in an osteoarticular infection in children is rare. We report the case of two siblings with an osteoarticular infection in the hip and in the knee, respectively, who developed deep vein thrombosis and, in one sibling, pulmonary thromboembolism. The only hematological alteration found was reduction of anti-thrombin III in both patients. This reduction was acquired and secondary to sepsis due to Staphylococcus aureus. Anti-thrombin III levels recovered after 2 weeks of treatment. The association of deep vein thrombosis and osteoarticular infection with sepsis should lead to suspicion of hematological deficiencies, including acquired anti-thrombin III deficiency.

Trombosis venosa profunda asociada a infección osteoarticular en dos hermanos con deficiencia de antitrombina III / Deep vein thrombosis associated with osteoarticular infection in two siblings with anti-thrombin III deficiency

La aparición de trombosis venosa profunda en la infección osteoarticular en niños es una asociación rara. Comunicamos el caso de dos hermanos con infección osteoarticular de la cadera y de la rodilla, respectivamente, que desarrollaron trombosis venosa profunda, y en uno de ellos, tromboembolismo pulmonar. Sólo se encontró como alteración hematológica disminución de la antitrombina III (AT III) en los dos pacientes. Esta disminución fue adquirida y secundaria a la sepsis que presentaron por Staphylococcus aureus. Las concentraciones de AT III se recuperaron a las 2 semanas de tratamiento. La asociación de trombosis venosa profunda e infección ostearticular con sepsis debe hacernos pensar en deficiencias hematológicas, entre ellas la deficiencia adquirida de AT III

The development of deep vein thrombosis in an osteoarticular infection in children is rare. We report the case of two siblings with an osteoarticular infection in the hip and in the knee, respectively, who developed deep vein thrombosis and, in one sibling, pulmonary thromboembolism. The only hematological alteration found was reduction of anti-thrombin III in both patients. This reduction was acquired and secondary to sepsis due to Staphylococcus aureus. Anti-thrombin III levels recovered after 2 weeks of treatment. The association of deep vein thrombosis and osteoarticular infection with sepsis should lead to suspicion of hematological deficiencies, including acquired anti-thrombin III deficiency