Efficacy and Safety of the Safe Triangular Working Zone Approach in Percutaneous Vertebroplasty for Spinal Metastasis

Clinical benefits of CT-guided microwave ablation combined with percutaneous vertebroplasty for spinal metastases: Local tumor control and a multivariate analysis of bone cement leakage

BACKGROUND AND PURPOSE

CT-Guided Microwave Ablation Combined with Percutaneous Vertebroplasty for Spinal Metastases is an emerging minimally invasive therapeutic option. This study aimed to compare the clinical efficacy and risk factors for bone cement leakage in CT-guided percutaneous vertebroplasty (PVP) with or without microwave ablation (MWA) in the treatment of spinal metastases.

MATERIALS AND METHODS

A retrospective analysis was conducted on 69 patients with 104 vertebral metastases treated between January 2019 and December 2022, divided into two groups: PVP group(n = 23, 37 vertebrae) underwent PVP alone, and MWA + PVP group(n = 46, 67 vertebrae) underwent MWA combined with PVP. Postoperative pain, daily living capabilities, and other parameters were compared, and CT and MRI were used to assess bone cement leakage and tumor control. Logistic regression analysis was used to evaluate the risk factors for leakage.

RESULTS

The technical success rate was 100 % for both groups.The Visual Analog Scale（VAS), Daily Morphine Consumption(DMC), Oswestry Disability Index(ODI), and Activity of Daily Living Scale(ADL) scores at various postoperative time points in both the PVP and MWA + PVP groups showed significant improvements compared to preoperative levels (P < 0.05). However, there were no significant differences between the two groups within 12 weeks (P > 0.05), but at the 24-week follow-up, the MWA + PVP group exhibited superior scores (P < 0.05).At the 24-week postoperative follow-up, the local tumor control rates for patients and lesions in the PVP group were 78.26 % (18/23) and 78.38 % (29/37), respectively, while those in the MWA + PVP group were 91.30 % (42/46) and 91.04 % (61/67), respectively. PVP group had mild bone cement leakage in 64.80 % of vertebrae, compared to 22.30 % in MWA + PVP group. Multifactorial logistic analysis revealed that microwave ablation is an independent protective factor against bone cement leakage, cortical bone cement leakage, and vascular bone cement leakage, with an approximately consistent odds ratio (OR) of 0.2 for its protective effect, and these associations were statistically significant (P-values of 0.008, 0.005, and 0.007, respectively).Conversely, Pathological fractures (OR = 29.6,P < 0.001)and posterior vertebral wall ruptures（OR = 17.3,P = 0.01） were two independent risk factors for bone cement leakage, and the volume of bone cement injected was an independent risk factor for spinal canal bone cement leakage （OR = 1.7, P = 0.01）.

CONCLUSION

Compared with PVP alone, MWA combined with PVP in the treatment of spinal metastases not only demonstrates more pronounced tumor control efficacy but also effectively reduces the risk of bone cement leakage. This finding offers a novel perspective for the minimally invasive treatment of spinal metastases and provides robust clinical evidence for optimizing treatment regimens and enhancing patients' quality of life. It holds promise as one of the significant options in the therapeutic arsenal against spinal metastases.

Incidence of Cement Leakage and Potential Risk Factors in Surgery for Spinal Metastasis: A Systematic Review and Meta-Analysis

OBJECTIVES

The current meta-analysis was performed to gather available evidence regarding the incidence and risk factors of cement leakage (CL) in patients undergoing surgical procedures for spinal metastasis.

METHODS

Two authors independently searched the PubMed, Embase, and CENTRAL databases. Clinical studies reporting the incidence or risk factors of CL were included for analysis. The primary outcome analyzed was the incidence of various types of CL. Random-effects or fixed-effects single-proportion meta-analyses were conducted to pool the available evidence, based on the heterogeneity test. Subgroup analyses were conducted based on surgical procedures (percutaneous vertebroplasty, percutaneous kyphoplasty, and others). Risk factors of CL were synthesized narratively to identify the most commonly accepted factors.

RESULTS

A total of 26 studies, involving 2551 patients, were included. The number of operated spine segments was reported in 23 studies, accounting for 4101 vertebrae. The pooled incidences of general, intradiscal, paravertebral, spinal canal, and intravascular CLs were 0.18 (95% confidence interval [CI], 0.11-0.28), 0.14 (95% CI, 0.08-0.21), 0.13 (95% CI, 0.06-0.21), 0.11 (95% CI, 0.05-0.19), and 0.12 (95% CI, 0.08-0.17), respectively. Subgroup analyses revealed significantly different incidences of general CL (0.37 vs. 0.06 vs. 0.09, P < 0.01), intradiscal CL (0.22 vs. 0.06 vs. 0.12, P < 0.01), paravertebral CL (0.25 vs. 0.03 vs. 0.06, P < 0.01), and vascular CL (0.14 vs. 0.03 vs. 0.15, P < 0.01) among the three groups. Posterior wall disruption, pathologic fracture, and the number of treated vertebral levels were the most commonly identified independent risk factors for general CL. Posterior wall disruption was determined as a common significant risk factor for spinal canal CL.

CONCLUSIONS

This review provides insights into the incidence and risk factors associated with CL in surgical procedures for spinal metastasis. Understanding these risk factors can contribute to the development of tailored strategies aimed at minimizing CL occurrence and optimizing surgical outcomes for patients undergoing spinal metastatic surgery.

The role of minimally invasive surgery within a multidisciplinary approach for patients with metastatic spine disease over a decade: A systematic review

BACKGROUND

Metastatic spine disease (MSD) occurs commonly in cancer patients causing pain, spinal instability, devastating neurological compromise, and decreased quality of life. Oncological patients are often medically complex and frail, precluding them form invasive procedures. To address this issue, minimally invasive spinal surgery (MISS) techniques are desirable. The aim of this study is to review published peer-reviewed literature and ongoing clinical trials to provide current state of the art.

METHODS

A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, assessing MISS in MSD patients for the period 2013-2023. Innovations under development were assessed by querying and reviewing data from currently enrolling U.S. registered clinical trials.

RESULTS

From 3,696 articles, 50 studies on 3,196 patients focused on spinal oncology MISS. The most commonly reported techniques were vertebral augmentation (VA), percutaneous spinal instrumentation, and radiofrequency ablation (RFA). Surgical instrumentation/stabilization techniques were reported in 10/50 articles for a total of 410 patients. The majority of studies focused on pain as a primary outcome measure, with 28/50 studies reporting a significant improvement in pain following intervention. In the United States, 13 therapeutic trials are currently recruiting MSD patients. Their main focus includes radiosurgery, VA and/or RFA, and laser interstitial thermal therapy.

CONCLUSIONS

Due to their medical complexity and increased fragility, MSD patients may benefit from minimally invasive approaches. These strategies are effective at mitigating pain and preventing neurological deterioration, while providing other advantages including ease to start/resume systemic/radiotherapy treatment(s).