2022, Vol. 26 ›› Issue (21): 3381-3388

Biomechanical properties of a novel bone cement screw and traditional methods for Kummell’s disease

Zhan Yi1, 2, Kang Xin1, Wang Yuhang1, Zhang Haiping1, He Simin1, Sun Honghui1, Hao Dingjun1, Wang Biao1   

Abstract: BACKGROUND: The serious complication of bone cement displacement is easy to occur when Kummell’s disease is treated with common bone cement filling method.
OBJECTIVE: To analyze the biomechanical properties of the novel bone cement screw system, percutaneous vertebroplasty and percutaneous vertebroplasty combined with percutaneous pediculoplasty in treatment of Kummell’s disease with three-dimensional finite element method.
METHODS: The collected CT data in Kummell’s disease patients were imported into Mimics image processing software to read the images. A three-segment three-dimensional finite element model of T12, L1, and L2 vertebrae was established (L1 was the diseased segment), and a novel cement screw model was reconstructed with Creo software. The three-dimensional finite element model of Kummell’s disease was repaired and treated with five options: novel unilateral cement screw placement, novel bilateral cement screw placement, percutaneous vertebroplasty combined with unilateral percutaneous pediculoplasty, and percutaneous vertebroplasty combined with bilateral percutaneous pediculoplasty, and pure percutaneous vertebroplasty. Maximum equivalent stress of T12 inferior endplate, maximum Von-Mises of bone cement, relative displacement of bone cement, and stability of bone cement under flexion, extension, left flexion, right flexion, and rotation conditions were analyzed.
RESULTS AND CONCLUSION: (1) There was little change in the stress distribution of the inferior endplate of T12 under different schemes, and the maximum Von-Mises of inferior endplate of T12 of percutaneous vertebroplasty combined with unilateral and bilateral percutaneous pediculoplasty group was larger under different working conditions. The maximum Von-Mises of inferior endplate of T12 of other groups was smaller. (2) The maximum Von-Mises of bone cement of percutaneous vertebroplasty group was obviously larger than that of the other four schemes, and its stress distribution was not uniform. (3) The bone cement displacement of percutaneous vertebroplasty group was the largest under most working conditions, and the relative displacement of the bone cement in the other schemes was different under different working conditions. The relative displacement of the bone cement in the novel unilateral and bilateral cement screw groups was small under flexion, extension and lateral flexion. Under the rotation, there was no significant difference in the relative displacement of the bone cement between the novel unilateral and bilateral cement screw group and the percutaneous vertebroplasty combined with unilateral and bilateral percutaneous pediculoplasty group. (4) The cement displacement load ratio of novel unilateral and bilateral bone cement screw group was higher than those of other schemes. (5) Results showed that for the treatment of Kummell’s disease, the use of a novel bone cement screw treatment will have a more stable structure, can effectively avoid bone cement displacement. However, this study requires clinical confirmation of its practicability in the treatment of Kummell’s disease.
Key words: Kummell’s disease, novel bone cement screw, thoracolumbar vertebrae, finite element analysis, internal fixation, biomechanics