Biomechanical analysis of a novel bone cement bridging screw system for the treatment of Kummell disease: a finite element analysis.

When bone cement is used to strengthen the vertebrae in patients with Kummell disease (KD), loosening and displacement of cement are common complications that can cause poor results. We developed a bone cement bridging screw system to avoid this complication. This three-dimensional finite element study aims to analyze the biomechanical properties of the novel bridging screw system and compare it to single vertebroplasty and vertebroplasty combined with pediculoplasty. After the effective establishment of a KD three-dimensional finite element model, the stability of the bone cement in the five treatment methods was analyzed and compared on four aspects. According to the calculation results of the maximum von Mises stress of bone cement and the relative displacement ratio of bone cement, it was determined that the stability of the bone cement was significantly improved when combined with the bridging screw system or pediculoplasty. In addition, according to the calculation results of the maximum von Mises stress of the inferior endplate of T12 and the displacement load ratio of the bone cement, we further found that after using the bridging screw system, the bone cement in the vertebral body has the best stability, and the risk of bone cement loosening or displacement is the lowest. In conclusion, for treating KD with bone cement augmentation, the bone cement bridging screw system combined with vertebroplasty has better stability and safety than ordinary single vertebroplasty and vertebroplasty combined with pediculoplasty. This treatment approach has the most robust ability to avoid loosening and displacement of bone cement.