Partially biodegradable polyacrylic-polyester composites for internal bone fracture fixation

New partially resorbable composite formulations based on components used in surgery were synthesized in rod form (length 15-20 mm, diameter 4 mm). The biostable components were poly(methyl methacrylate) in hydrophobic implants and poly(2-hydroxy ethyl methacrylate) in hydrophilic ones. The biodegradable components were commercially available suture yarn made from poly (alpha-hydroxy esters): polyglycolide, a polyester derived from glycolic acid; and a copolyester of glycolic and lactic acids, polyglactin 910. Biodegradation in phosphate-buffered solution at pH 7.0 and 37 +/- 0.5 degrees C was analysed gravimetrically. There was no measurable loss of mass after treatment for 20-25 d. Composite microstructure was examined by phase-contrast, cross-polarized light microscopy.