Clinical Study Of Bone-filled Mesh Bag Vertebroplasty Combined With ¹²⁵Ⅰ Seed Implantation In The Treatment Of Spinal Metastases With Posterior Vertebral Body Defects

Objective（s）:To investigate the feasibility,safety,and clinical efficacy of bone-filled mesh bag vertebral body molding combined with ¹²⁵Ⅰ seeds implantation in the treatment of posterior vertebral defects caused by spinal metastases.Methods:A retrospective analysis was conducted on 62 patients with posterior vertebral defects caused by spinal metastases who underwent surgical treatment in the Department of Orthopedics at our hospital from May 2018 to August 2022.According to the difference in treatment methods,these patients were divided into two groups:the PVPI group（observation group）with 32 cases and the MPVPI group（study group）with30 cases.The visual analog scale（VAS）and the Karnofsky Performance Status（KPS）scores were compared between the two groups on postoperative day 1,1 month,3months,and 6 months after surgery.The postoperative complications and long-term survival time were also compared.Statistical analysis of the general data and index changes and differences between the two groups were performed using t-tests and variance analysis,and the survival rates of the patients were analyzed by the Kaplan-Meier log-rank test and Cox regression analysis.Results:Intraoperative blood loss:The control group had a mean intraoperative blood loss of 7.27±3.511 ml,while the study group had a mean intraoperative blood loss of11.7±17.54 ml.There was no statistically significant difference in intraoperative blood loss between the study and control groups（P>0.05）.Changes in VAS score:1)There was no significant difference in preoperative VAS score between the PVPI group and the MPVPI group（P>0.05）,with mean scores of7.031±0.809 and 7.067±0.727,respectively.2)On the first day after surgery,the mean VAS scores for the PVPI and MPVPI groups were 3.781±0.960 and 3.366±1.663,respectively,and there was no significant difference in scores between the two groups（P>0.05）.3)One month after surgery,the mean VAS scores for the PVPI and MPVPI groups were 3.839±1.461 and 3.3±1.969,respectively,and there was no significant difference in scores between the two groups（P>0.05）.4)Three months after surgery,the mean VAS scores for the PVPI and MPVPI groups were 3.417±1.730 and2.542±1.936,respectively,and there was no significant difference in scores between the two groups（P>0.05）.5)Six months after surgery,the mean VAS scores for the PVPI and MPVPI groups were 3.05±1.830 and 2.095±1.688,respectively,and there was no significant difference in scores between the two groups（P>0.05）.The changes in Karnofsky Performance Status（KPS）were as follows:the mean KPS score in the PVPI group was 63.438±9.877 before surgery,while it was62.33±11.742 in the MPVPI group.Comparison revealed no significant difference in the preoperative KPS score between the two groups（P>0.05）.On the first day after surgery,the mean KPS score was 65±10.000 in the PVPI group and 65±12.042 in the MPVPI group.Comparison revealed no significant difference in the KPS score between the two groups on the first day after surgery（P>0.05）.At one month after surgery,the mean KPS score was 67.742±10.383 in the PVPI group and 66.333±17.026 in the MPVPI group.Comparison revealed no significant difference in the KPS score between the two groups at one month after surgery（P>0.05）.At three months after surgery,the mean KPS score was 70±10.801 in the PVPI group and 71.667±16.750 in the MPVPI group.Comparison revealed no significant difference in the KPS score between the two groups at three months after surgery（P>0.05）.At six months after surgery,the mean KPS score was 71.5±13.143 in the PVPI group and 78.571±12.066 in the MPVPI group.Comparison revealed no significant difference in the KPS score between the two groups at six months after surgery（P>0.05）.Complication profile:Among the 41 treated vertebral levels in the PVPI group,15（36.6%）demonstrated cement leakage,of which 7 levels（17.1%）showed paravertebral soft tissue leakage and 8 levels（19.6%）had intradiscal leakage.In the MPVPI group,3 of the 42 treated vertebral levels（7.1%）had cement leakage,all of which were paravertebral soft tissue leaks.The difference in cement leakage rates between the two groups was statistically significant（P<0.05）.However,none of the patients in either group experienced cement syndrome.No postoperative complications such as spinal cord or nerve root compression symptoms,radiation-induced myelopathy,infection,nerve paralysis,or nerve root pain syndrome were observed in any of the patients.Conclusion（s）:1.Patients with vertebral metastases with posterior vertebral body defects can effectively alleviate pain symptoms,improve functional status,and quality of life,regardless of whether they receive PVPI or MPVPI treatment.2.Both PVPI and MPVPI are effective methods for treating vertebral metastases with posterior vertebral body defects,but mesh-bag PVPI has a lower incidence of bone cement leakage and fewer postoperative complications,making it safer and more reliable.3.Compared to traditional PVPI procedures,MPVPI has shown feasibility in the treatment of vertebral posterior defect metastatic tumors by modifying surgical instruments.The operational requirements are relatively simple,which has expanded the surgical indications for this type of patients.