system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: METHODS, OBJECTIVE, BACKGROUND, METHODS, RESULTS. Meshes: .
user
Does an In Vitro Evaluation of Fracture Reduction Achieved by Inflatable Bone tamp under Simulated Physiological Load? Context: An in vitro biomechanical study. To determine the fracture reduction achieved by a novel inflatable bone tamp under simulated physiological load. Previous biomechanical studies have showed that kyphoplasty allows near total restoration of lost vertebral height in unloaded conditions and partial height restoration under simulated physiological loads. Clinically, loss of reduction has been observed after bone tamp deflation, prior to cement injection. The present study evaluated fracture reduction achieved by an inflatable bone tamp during kyphoplasty while maintaining physiological load. Comparison to commercially available inflatable bone tamp was also performed. Eighteen osteoporotic vertebral bodies (T11-L4) were alternately assigned to one of the two treatment groups: Group A - AFFIRM™ (Algea Thearpies, a division of Globus Medical Inc., Audubon, PA); and Group B - KYPHON (Kyphon Inc., Sunnyvale, CA). The vertebral bodies were compressed axially on an MTS Bionix 858 machine at a rate of 5 mm/min until compressed to 40% of the initial anterior height. Load versus displacement was recorded. The fractured VBs then underwent kyphoplasty with cement augmentation. The augmented vertebral bodies were then re-compressed and anterior vertebral body height (mm) and wedge angle (degrees) was measured initially, after mechanically creating an anterior wedge fracture, and after repairing the compression fracture. Each vertebral body was subjected to 111 N load to simulate in vivo physiologic loading during inflation and cement augmentation. The vertebral height, wedge angle, cement volume, and inflation pressures were compared between the treatment groups using an unpaired t-test (P<0.05). Failure loads were compared between intact and repaired VBs using a paired t-test (P<0.05). Average lost height restored in Group A was 29%, and 30% in Group B compared to the compressed state. Similar trends were observed in the mean changes of vertebral body wedge angle in both the groups. No significant difference in mean inflation pressures (Group A 182±33 psi; Group B 175±37 psi) were found between the two groups. Average percentage increase in failure load was 218% and 241% for Group A and B, respectively. Mean injected cement volume was 6.65±0.65 cc and 6.73±0.41 cc for Group A and B, respectively.
assistant
Some height restoration was observed using the two bone tamps in fractured vertebral bodies under simulated physiological load. The fracture reduction achieved by the two inflatable bone tamps was equivalent. No significant difference between mean inflation pressures and failure load was demonstrated between the two groups. Final Decision: yes