A feasibility study on long-distance bone cement injection during vertebral augmentation

Abstract

Objective To compare the pressure with long-distance vs conventional bone cement injection during vertebral augmentation, and to investigate the feasibility of long-distance bone cement injection during this procedure. Methods Bone cement was injected into a plastic container under room temperature (20 ℃) using mechanical testing machine at a constant velocity to mimic the clinical vertebral augmentation. Injection force was measured according to the forward length of injection rods: 30 mm, 60 mm, 90 mm, 120 mm and 150 mm. The mean pressures with long-distance vs conventional bone cement injection were compared. The bone cement injection started at 7 min after the powder-liquid mixture, at a velocity of 0.05 ml/s, sustained up to the end of three syringes (each syringes contains 1.5 ml cement). All of the injection pressures were measured for three times respectively with two injection methods. Results The mean pressure and maximum pressure with the long-distance vs conventional bone cement injection for the first syringe was (14.93 ± 4.31) N vs (7.83 ± 4.36) N; for the second syringe, (24.93 ± 9.47) N vs (8.96 ± 6.43) N; for the third syringe, (32.87 ± 13.16) N vs (13.27 ± 5.73) N (all P<0.05). Conclusion Long-distance bone cement injection yields pressure that is higher than conventional cement injection yet still within the strength range of an average person. The modified vertebral augmentation device is structurally stable for use in long-distance bone cement injection. Key words: Fracture, compression; Vertebroplasty; Pressure