O-arm navigated excision and vertebroplasty of pediatric aggressive vertebral hemangioma with compressive myelopathy: A case report

Abstract

Introduction

Vertebral hemangioma (VH) is the most common angiomatous tumor usually asymptomatic and is incidentally noticed on MRI. The incidence of VH is rare in the pediatric population. The extraosseous extension is termed an Aggressive Vertebral Hemangioma (AVH) and these often need surgical management. Intraoperative stereotactic navigation for tumor excision helps in planning- localizing the tumor and delineating its margins.

Case presentation

A 14-year-old boy presented with thoracic myelopathy signs. The MRI scan suggests T1 and T2 hyperintense signals within the T6 vertebral body with extramedullary extradural space occupying the lesion. The CT scan showed a “polka dot” appearance. Preoperative endovascular embolization followed by surgical decompression with posterior instrumented stabilization under O-arm navigation and tumor excision was planned. Cystic extradural lesion excised and vertebroplasty done at T6 level. Histopathology slides confirmed hemangioma.

Discussion

The most common age of involvement is between 30 and 70 years it is rarely seen in the pediatric age group. To the best of our knowledge, fewer than 20 cases of pediatric aggressive vertebral hemangiomas have been reported. Based on a review of pediatric AVH only 4 patients have been treated with preoperative vascular embolization followed by surgical decompression and stabilization. O-arm navigated AVH excision and vertebroplasty has never been described in the literature; this being the first case. It also aids in the identification of tumor margins along with real-time monitoring of adequate resection.

Introduction

Vertebral hemangioma (VH) is the most common angiomatous tumor with an incidence of 10–12% of the population based on large autopsy series as observed by Fox and Onofrio [1]. The incidence of VH is more in adults as compared to the pediatric population [2]. It is a benign vascular tumor that develops from malformed vascular endothelium and is composed of slow-flowing venous channels [3]. These lesions are usually asymptomatic and are incidentally noticed on MRI. Symptoms develop in case of extraosseous extensions or in case of a pathological fracture. 1% of VH has extraosseous extension and is termed as Aggressive Vertebral Hemangioma (AVH) which can lead to varied symptoms based on the site of involvement as per F J Cloran et al. [4]. Vertebroplasty is an alternative treatment option that is avoided in AVH due to the risk of epidural leakage of cement [5]. O-Arm (Medtronic, Minneapolis, USA) is a third-generation spine navigation system, which incorporates intraoperative CT scanners combined with the computer software system. This system comes with a set of navigated instruments, which allows the surgeon to access real-time, three-dimensional images of the spine in relation to the surgical instruments which assist in accurate pedicle screw insertion. This navigation system also plays an important role in planning- localizing tumor margins, and monitoring the cement spread increasing the safety of the procedure [6]. We are reporting a rare case of an aggressive vertebral hemangioma in the T-6 vertebra in a pediatric patient presenting with compressive thoracic myelopathy. O-arm navigated AVH excision and vertebroplasty has never been described in the literature; this being the first case of AVH treated with preoperative vascular embolization, followed by laminectomy, instrumented fusion, and vertebroplasty under the assistance of O-arm and navigation.

Case presentation

A 14-year-old boy presented in the spine outpatient clinic of a tertiary care orthopedic hospital with complaints of mid-back pain for 6 months and gait instability for 1 month. On examination, the patient had axial tenderness over spinous processes in the thoracic region. The neurological examination documented signs of thoracic myelopathy including both lower limb spasticity, brisk knee and ankle jerk with ill-sustained ankle clonus with positive Babinski sign. The patient was unable to walk without support with hypoesthesia below the T6 dermatome with sacral sparing and intact bladder and bowel function. Neurological Examination as per International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) has been mentioned in Table 1.

Table 1.

Patient’s neurological examination and the score calculation as per International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI).

Component	Region	Score on Right side	Score on Left side	Total
Motor	Upper Extremity	50	50	100
	Lower Extremity	17	17	34
Sensory	Light Touch	35	41	76
	Pin Prick	40	43	83
Neurological Level of Injury		T 6
ASIA Impairment Score (AIS)		D

The patient was investigated with a plain thoracolumbar radiograph (Fig. 1A, B) which was suggestive of a sclerotic lesion in the T6 vertebral body with prominent trabecular markings. The coronal and sagittal alignment of the vertebral column was well maintained. The MRI thoracolumbar spine (Fig. 2A–G) was suggestive of a T2 hyperintense signal within the T6 vertebral body with trabecular prominence and extramedullary extradural space-occupying lesion originating from the left pedicle and causing spinal cord compression with features of spinal cord edema. T1 images also showed hyperintensity suggestive fat content of the tumor [3]. Post-contrast images (Fig. 2C, F, G) confirmed the enhancement of the lesion. CT scan (Fig. 1C–F) showed trabecular prominence in sagittal and coronal sections, axial sections showed a “polka dot” appearance of the vertebral body with an ossified lesion within the vertebral canal adjacent to the left pedicle causing bony canal stenosis.

Fig. 1. Pre-operative Xray and CT scan of the thoracic spine.

A, B AP and Lateral X-Ray dorsal spine- T 6 vertebra (white triangle) prominent trabeculae with maintained vertebral body height. C – Coronal, F- Sagittal CT scan cuts – (white arrow) radio dense prominent trabeculae. D, E Axial CT scan cuts- Polka dot appearance, ossified extraosseous extension of tumor (black arrow).

Fig. 2. Pre-operative MRI of the thoracic spine.

A T1 WI sagittal cut – T6 hyperintensity (white triangle) suggesting fat-containing tissue, B T2 – hyperintense T6 body (black triangle) suggestive of fat, edema, and vascular content, C Post-contrast sagittal (white arrow) (F) coronal (yellow arrow) showing homogenous enhancement within the body and extraosseous extension of tumor, D T1 axial cut (White asterisk) hypointense extraosseous extension of tumor with polka dot sign in body, E T2 axial cut with epidural hyperintense tumor with cord compression. G Axial post-contrast cut- (Black asterisk) showing epidural hyperintense tumor with polka dot sign in body.

Surgical decompression with T5-T6 laminectomy and tumor excision with posterior instrumented stabilization T5-T7 was planned after relevant blood investigations and written informed consent. Preoperative embolization of the branch of the feeding vessel to the tumor was done with polyvinyl alcohol particles (Fig. 3A, B), a day before surgery. Under general anesthesia, in a prone position posterior, midline exposure was done. A minimally invasive reference array (MIRA) was attached to the T4 spinous process and navigated instruments were verified. The first 3-D O-arm scan was done, followed by T5 and T7 bilateral pedicle screw insertion under navigation guidance. (Fig. 3D). Pedicle entry and screw tract were created with navigated instruments in the T6 vertebra, and the integrity of the pedicle walls was confirmed with pedicle sound. Jamshidi needles were inserted within the tract through T6 pedicles and their position was confirmed with intraoperative fluoroscopy (Fig. 4A). Vertebroplasty cement was injected through the needles and cement spread and position was confirmed which was found to be satisfactory. T5 and T6 laminectomy was done with bur and nibbler. The cystic extradural lesion was identified within the spinal canal, which was removed in a piecemeal manner and the cord was decompressed (Fig. 3C). The wound closed in layers over the drain.

Fig. 3. Intraoperative endovascular embilisation, clinical and navigation screen.

A Pre-embolism digital subtraction angiography (DSA) showing vascular blush, B Post-endovascular embolism DSA with complete embolization of the feeding vessel. C intraoperative image – complete excision of T5, T6 laminae with T6 partial pedicle excision and epidural tumor excision. D Intraoperative navigation T5 left pedicle probing with the navigated probe with screw length estimation.

Fig. 4. Intraoperative CT image, Postoperative Xray and Histopathology images.

A Intraoperative 3D CT with Jamshidi needle in-situ confirming position of needles and screws, B, C AP and lateral view of postoperative x-ray with T6 vertebroplasty and T5, T7 pedicle screw in situ. D Histopathology slide- dilated capillaries, cavernous spaced (Black triangle black arrow), trabecular bone (black asterisk) confirming vertebral hemangioma.

On POD-1 icing and light joint compression exercises were started, and the patient was made to stand with support with TLSO on POD-2. On POD-7 task-oriented exercises for reducing the spasticity were introduced. A motor learning program was introduced to improve the gait on POD-15. During the entire rehabilitation program, the Patient started walking with minimal support on 12 weeks follow-up. In 6 months follow-up spasticity disappeared and normal bladder bowel function was maintained.

Histopathology slides (Fig. 4D) of the lesion showed bits of trabecular bone with intervening areas of nodular collection of dilated capillaries and a few cavernous spaces suggestive of osseous hemangioma. On 6 month follow-up, the patient was neurologically normal, and a review CT scan and MRI scan done after 1 year (Fig. 5) showed no signs of recurrence with satisfactory implant position and Bridwell grade 3 fusion.

Fig. 5. One year follow-up CT scan images.

A–C 1-year follow-up CT scan coronal, sagittal, and axial cut- with vertebroplasty cement in acceptable position, D, E T2 WI axial and sagittal cut- adequately decompressed cord without tumor recurrence, F 3D CT scan showing acceptable implant position.

Discussion

Extraosseous extension, vertebral fracture, or intradural extension of vertebral hemangioma is labeled as an AVH. 1% of VH are aggressive which can lead to symptoms like progressive mechanical back pain, myelopathy, claudication, and radiculopathy depending on the level and size of involvement as per F J Cloran et al. [4]. Thoracic vertebrae are the most commonly involved site followed by lumbar vertebrae. Both the anterior vertebral body and posterior elements can harbor AVH [4, 5]. The most common age of involvement is between 30–70 years; it is rarely seen in the pediatric age group. To the best of our knowledge, fewer than 20 cases of pediatric aggressive vertebral hemangiomas have been reported till now [6–17]. In pregnant women, more aggressive forms of VH are seen due to higher levels of circulating estrogen and progesterone within the body [17].

Pankaj Singh et al. [12] published the largest series of pediatric AVH of 7 patients, all of them underwent decompression and stabilization, but before surgery, all of them were treated with intralesional ethanol injection. The complication observed by them was intraoperative hypotension in 2 patients. However, Doppman et al. [18] treated adult AVH patients with intralesional ethanol injection and observed late pathological fracture of an involved vertebra [7, 8, 13].

Based on a review of pediatric AVH, only 4 patients have been treated with preoperative vascular embolization followed by surgical decompression and stabilization [7, 8, 13]. Endovascular embolization in the preoperative period helps in controlling intraoperative bleeding. Kato et al. [8] performed preoperative endovascular embolization before corpectomy but noted intraoperative blood loss to the tune of 1500–3000 ml. In the reported case endovascular embolization was performed 24 h before the surgery, which reduced vascularity and allowed intraoperative blood loss to be limited to 480 ml. Epidural spread of vertebroplasty cement is also prevented by preoperative endovascular embolism [19]. Torrential bleeding was one of the most dreadful complications of piecemeal resection, but with preoperative endovascular embolization, bleeding is significantly reduced leading to frequent piecemeal resections [5].

Polymethyl Methacrylate (PMMA) cement can be injected into the hemangioma as it provides hemostatic embolization, structural support to prevent pathological collapse, and significant pain relief in AVH [19]. Cement leakage into epidural space is a dreadful complication of vertebroplasty in AVH, which can be avoided by monitoring the cement spread within the void in the vertebral body due to which percutaneous procedure is contraindicated in patients with AVH especially when there is an extradural extension. Intraoperative Computed Tomography Navigation by O-arm plays an important role in monitoring the spread of cement increasing the safety of the procedure. The navigation system also aids in the identification of tumor margins with the help of navigated pedicle sound ensuring the adequacy of tumor resection avoiding breaches in the walls of the vertebral body and making it feasible for vertebroplasty. The usefulness of O-arm in increasing the accuracy of pedicle screws in complex clinical situations like deformity or dysplasia has been proven [20]. However, the limitation of O-arm navigation is that it cannot assist in the identification and excision of soft tissue components of the tumor [21].

Conclusion

Aggressive Vertebral Hemangioma is a rare tumor and its incidence in the pediatric age group is unique. Epidural extension of the tumor causes myelopathy and radiculopathy which needs surgical decompression and fusion. Preoperative endovascular embolization reduces intraoperative blood loss and allows piecemeal resection. O-arm navigation helps in accurate screw placement and real-time assessment of adequate tumor excision and intraoperative confirmation of vertebroplasty cement placement.

Author contributions

AK: Conceptualization, Methodology, Supervision, project administration; NS: Data curation, writing draft, visualization; SA: Modification of primary draft, investigation, review and editing, project administration; PB: Supervision, project administration; review and editing, SH and PS: Supervision, project administration. All authors read and approved the final manuscript.

Funding:

The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Data availability

Data is not a part of a public repository.

Competing interest

The authors have no relevant financial or non-financial interests to disclose.

Consent to participate

Informed consent was obtained from all individual participants included in the study.

Ethics committee approval

Approval of the institutional Ethics Committee (Sancheti Hospital Institutional Ethics Committee) has been obtained.

Guidelines

This care report has been prepared in accordance with the CARE – Case report guidelines and the Declaration of Helsinki.

Supplementary information

The online version contains supplementary material available at 10.1038/s41394-025-00717-x.