Screw Fixation in Cancellous Osteoporotic Bone – First in Vitro Results with a Novel Augmentation Material

摘要: Background: Screw fixation during internal of osteoporotic fractures can be difficult due to severe reduction bone mass and structure in these patients. Material Methods: The use PMMA-bone cement anchor implants patients a “combined osteosynthesis” has empirically been developed. irreversibility this methodology is currently limiting it exceptional salvage cases pathological fractures. A new degradable screw augmentation material was therefore developed on the basis alkylene bis(oligolactoyl)methacrylates. mechanical properties polymer were tested by pull-out torque tests augmenting cancellous stainless steel screws non-osteoporotic bovine blocks polypropylene blocks. In tests, improved significantly material. Results: maximum force obtained showed an 256% increase compared standard system. torques measured up 400% higher than for vitro degradation kinetics standardized system showing almost linear weight loss 2–3% per week between weeks 2 16. Conclusion: For further development vivo models must They should include either considerable overdrilling normal or human bone.