Biodegradable self-reinforced polyglycolide (SR-PGA) composite rods coated with slowly biodegradable polymers for fracture fixation: strength and strength retention in vitro and in vivo

Abstract The strength retention of coated and uncoated self-reinforced polyglycolide (SR-PGA) rods was evaluated after immersion in distilled water at 37°C and after implantation in the subcutis of rabbit. Slowly biodegradable coatings improved only the in-vitro strength retention of SR-PGA osteosynthesis implants. In the in-vivo environment the rods lost their strength in 5–6 weeks, and there was no significant difference in the strength retention between coated and uncoated rods. The SR-PGA rods lost their strength considerably faster in vivo than in vitro.