Percutaneous bipolar radiofrequency ablation for spine metastatic lesions

Is Radiofrequency Ablation Superior to Intra-Articular Injections for the Treatment of Symptomatic Knee Osteoarthritis?-A Systematic Review

The radiofrequency ablation (RFA) is considered a valid, minimally invasive treatment modality for the management of symptomatic knee osteoarthritis (OA). The aim of this study was to compare the outcomes of RFA with that of commonly used intra-articular injections for the persistent knee pain due to OA. Medline/Pubmed and Scopus databases were systematically searched up to April 2023 to identify studies comparing the effect of RFA and intra-articular injections (IAIs) on knee OA. Nine studies including 899 patients fulfilled the eligibility criteria and were included in the systematic review. The RFA procedure was related with improved knee pain relief compared to IAIs at 3-, 6- and 12-month follow-up (p < 0.001). Similarly, functional improvement was greater in RFA treatment than that observed after hyaluronic acid (HA), steroid or platelet-rich plasma (PRP) injections (Visual Analogue Scale p < 0.001, Numeric Rating Scale p = 0.019, Western Ontario and McMaster University Osteoarthritis Index p = 0.012). The overall procedural complication rate of RFA was 10.2% and was higher than steroid (p = 0.023) and PRP (p = 0.017) injections. However, no severe adverse events were reported. For patients with symptomatic knee OA, RFA seems to be more effective than IAIs in alleviating pain and improving joint function, despite the relatively higher incidence of non-serious adverse events. However, due to the limited number of studies and patients, this result should be interpreted with caution and not be generalized to the entire knee OA population.

Musculoskeletal oncology and thermal ablation: the current and emerging role of interventional radiology

The role of interventional radiology (IR) is expanding. With new techniques being developed and tested, this radiology subspecialty is taking a step forward in different clinical scenarios, especially in oncology. Musculoskeletal tumoral diseases would definitely benefit from a low-invasive approach that could reduce mortality and morbidity in particular. Thermal ablation through IR has already become important in the palliation and consolidation of bone metastases, oligometastatic disease, local recurrences, and treating specific benign tumors, with a more tailored approach, considering the characteristics of every patient. As image-guided ablation techniques lower their invasiveness and increase their efficacy while the collateral effects and complications decrease, they become more relevant and need to be considered in patient care pathways and clinical management, to improve outcomes. We present a literature review of the different percutaneous and non-invasive image-guided thermal ablation methods that are currently available and that could in the future become relevant to manage musculoskeletal oncologic diseases.

Risk factors for pulmonary cement embolism after percutaneous vertebroplasty and radiofrequency ablation for spinal metastases

Objective

Pulmonary cement embolism is a rare but underestimated complication of vertebroplasty due to the relative lack of study and examination. This study aims to investigate the incidence of pulmonary cement embolism in patients with spinal metastasis who undergo PVP with RFA and to analyze the relative risk factors.

Methods

A total of 47 patients were retrospectively included and classified into pulmonary cement embolism (PCE) group and non-pulmonary cement embolism (NPCE) group by comparing pre- and postoperative pulmonary CT scan images. The demographic and clinical information of the patients was obtained. Demographic data in the two groups were compared using the chi-square test for qualitative data and the unpaired t test for quantitative data. Multiple logistic regression analysis was used to identify risk factors related to pulmonary cement embolism.

Results

Pulmonary cement embolism was detected in 11 patients (23.4%), and all patients were asymptomatic and followed up regularly. Risk analysis showed that multiple segments (≥3, p=0.022), thoracic vertebrae (p=0.0008), and unipedicular puncture approach (p=0.0059) were risk factors for pulmonary cement embolism. There was a high incidence of pulmonary cement embolism if bone cement leaked into the para vertebral venous plexus in the thoracic vertebra (p<0.0001). Vein leakage of cement was related to the integrity of the vertebral cortex.

Conclusion

The number of involved vertebrae, lesion location, and puncture approach are independent risk factors for pulmonary cement embolism. There was a high incidence of pulmonary cement embolism if bone cement leaked into the para vertebral venous plexus in the thoracic vertebra. Surgeons should consider these factors when formulating therapeutic strategies.

Vertebral Body Bone Ablation with and without a Saline-Infused System in a Porcine Model

The purpose of this study was to evaluate the effect of bone radiofrequency (RF) ablation in the spine with and without controlled saline infusion. RF ablation with and without controlled saline infusion was performed in the vertebral bodies of 2 swine with real-time temperature and impedance recordings. Histology and magnetic resonance (MR) imaging results were reviewed to evaluate the ablation zone size, breach of spinal canal, and damage to the spinal cord and nerves. There was no difference in maximum and mean temperatures between controlled saline and noninfusion groups. The impedance and power output were not significantly different between the groups. MR imaging and histopathology demonstrated ablation zones confined within the vertebral bodies. Ablation zone size correlated on MR imaging and histopathology by groups. No ablation effect, breach of posterior cortex, spinal cord injury, or nerve or ganglion injury was observed at any level using MR imaging or histology. Controlled saline infusion does not appear to impact bone RF ablation and, specifically, does not increase the ablation zone size.

Update on Interventional Radiology of the Spine

Interventional radiologists now perform spinal interventions routinely for diagnostic and therapeutic purposes. New technologies for the management of spine pathologies have emerged with promising results in terms of safety and efficacy. Interventional radiology techniques in the spine include percutaneous biopsy and therapies for intervertebral disk herniation or spinal stenosis, facet and sacroiliac joint pathologies, vertebral and sacral fractures, and metastases. These techniques can also be easily combined one with the other or to further therapeutic approaches including systemic therapies, surgical approaches, and radiotherapy. This review provides a comprehensive overview of current percutaneous imaging-guided interventional radiology techniques in the spine. It will help readers become familiar with the most common indications, learn about different technical considerations during performance, and review the available evidence. Controversies concerning new products and technical approaches are also addressed.

Severe contracture in the lower extremity resulting from an osteoid osteoma of the lumbar spine in close proximity to neural elements in an adolescent: a case report

CASE

We report a rare case of a right-sided L4-5 facet osteoid osteoma in a 11-year-old female who presented with lower extremity pain, contractures, and gait disturbance in the setting of failed radiofrequency ablation. After open excision and single-level posterolateral fusion with instrumentation, her symptoms resolved and her spinopelvic parameters normalized.

CONCLUSIONS

This case highlights the contracture that may occur as a result of neurogenic pain from an osteoid osteoma in close proximity to neural structures.