Percutaneous radiofrequency ablation of osteoid osteoma

Outcomes of Osteoid Osteoma Treated by Percutaneous CT-Guided Radiofrequency Ablation

Introduction Osteoid osteomas are the most frequent true benign bone tumor in the adolescent age group and the third most prevalent benign bone tumor overall. This study was designed to assess the effectiveness of the procedure and correlate it with the analgesia offered because of the significant burden of this illness and new literature supporting the successful outcomes of image-guided percutaneous radiofrequency ablation (RFA) in osteoid osteoma. Methodology  This hospital-based interventional trial was carried out in a tertiary care referral center. Forty-two patients with osteoid osteoma, ranging in age from 9 to 30, were included in the study. The patients received RFA guided by computed tomography (CT), and they were postoperatively monitored at one, two, and four weeks and three, six months, and 12 months. A numerical pain scale (NPS) was used to evaluate the patient's pain both before and after the procedure. The preoperative and postoperative results were contrasted. Results A total of 42 participants were enrolled in the study. Eight (19.05%) women and 34 (80.95%) men made up the group. Complete pain alleviation (NPS=0) was attained in 42.8% and 96.4% of the study group in the first and second weeks post-procedure. Almost all patients began protected weight-bearing at one week, according to their level of pain tolerance. Osteoid osteoma of the talus was a remnant lesion in one patient that required further treatment after two weeks. During the duration of the follow-up, no problems were recorded. Conclusion Percutaneous CT-guided RFA of osteoid osteoma is a safe, minimally invasive procedure and greatly reduces the duration of hospitalization. It has excellent functional outcomes and no known complications.

Osteoid Osteoma of the Hand: Surgical Treatment versus CT-Guided Percutaneous Radiofrequency Thermal Ablation

(1) Background: Osteoid osteoma (OO) is one of the most common benign bone tumors. This type of osteogenic tumor is generally characterized by a well-defined lytic area with a vascularized central nidus surrounded by sclerosis and bone thickening. The wrist and hand bones are infrequent sites for osteoid osteoma: only 10% of the cases arise in these areas. Standard treatments are surgical excision and radio-frequency ablation (RFA), both with advantages and disadvantages. This study aimed to compare the two techniques to prove if RFA could be a potential alternative to surgery in the treatment of OO of the hand. (2) Methods: Patients treated for OO of the hand between January 2011 and December 2020 were evaluated and data was collected regarding the lesions' characteristics and the treatment outcome. Each patient was followed up for 24 months and VAS pain (Visual Analogue Scale), DASH (Disability of the Arm, Shoulder and Hand), and PRWE (Patient-Related Wrist Evaluation) scores were collected. (3) Results: A total of 27 patients were included in the study: 19 surgical and 8 RFA. Both treatments showed a significant improvement in pain and functionality. Surgery was associated with a higher complication rate (stiffness and pain), while RFA was associated with a higher recurrence rate (2/8 patients). RFA allowed for a speedier return to work. (4) Conclusions: We believe that osteoid osteoma treatment with RFA in the hand should be an available alternative to surgery as it allows rapid pain relief and a swift return to work. Surgery should be reserved for cases of diagnostic uncertainty or periosteal localization.

Recent Advances in the Treatment of Bone Metastases and Primary Bone Tumors: An Up-to-Date Review

In the last decades, the treatment of primary and secondary bone tumors has faced a slow-down in its development, being mainly based on chemotherapy, radiotherapy, and surgical interventions. However, these conventional therapeutic strategies present a series of disadvantages (e.g., multidrug resistance, tumor recurrence, severe side effects, formation of large bone defects), which limit their application and efficacy. In recent years, these procedures were combined with several adjuvant therapies, with different degrees of success. To overcome the drawbacks of current therapies and improve treatment outcomes, other strategies started being investigated, like carrier-mediated drug delivery, bone substitutes for repairing bone defects, and multifunctional scaffolds with bone tissue regeneration and antitumor properties. Thus, this paper aims to present the types of bone tumors and their current treatment approaches, further focusing on the recent advances in new therapeutic alternatives.

CT-guided radiofrequency ablation in osteoid osteoma: Result from a tertiary cancer centre in India

AIMS

The aim of this study is to evaluate the clinical efficacy of computed tomography (CT)-guided radiofrequency (RF) ablation as a minimally invasive therapy for osteoid osteoma.

MATERIALS AND METHODS

This is a retrospective analysis of prospectively maintained data of 43 symptomatic osteoid osteoma patients who were treated by radiofrequency ablation (RFA). Forty out of 43 patients were naive cases and underwent primary treatment for osteoid osteoma with RFA, whereas 3 patients included in the study underwent RFA for local recurrence after having undergone surgical treatment. Diagnosis was based on clinical and characteristic imaging findings, and biopsy was done for cases with atypical presentation. Pre and post procedure Visual Analog Score (VAS) was documented in all cases. Monopolar RFA system was used in all patients, and the electrode was placed within the lesion nidus under CT guidance coaxially through 11G introducer needle. Ablation was performed at 90° C for 5 min.

RESULTS

Technical success rate of intranidal placement of electrode was 100%. The primary clinical success in our study was 97.7% (42 of 43), and the secondary clinical success was 100%. Pre and postprocedure VAS score in our study group was 7.8 and 0.4, respectively. Mean follow-up period in our study was 48 months (Range: 4-129 months). One patient had recurrence of pain 4 years after treatment and was treated successfully by a second session. Minor complications were seen in 3 patients with two cases of RF pad burns and one case of skin burn at the treatment site, and these were managed conservatively. No patients developed temporary/permanent neurological deficits, and no procedure-related mortality was seen in our study.

CONCLUSION

CT-guided percutaneous RFA is a simple, safe, minimally invasive, and highly effective treatment option for osteoid osteoma with good long-term pain control and potentially low disease recurrence.

Osteoid Osteoma: An Updated Review of Epidemiology, Pathogenesis, Clinical Presentation, Radiological Features, and Treatment Option

Osteoid osteoma, the third most common benign bone tumor, usually occurs in the cortex of long bones. It consists of a radiolucent nidus surrounded by reactive osteosclerosis. Generally, osteoid osteoma affects young males. Nocturnal pain that eases with salicylates or nonsteroidal anti-inflammatory drugs (NSAID) is the typical clinical presentation. Sometimes, it remains undiagnosed for a long time. Plain radiography and computed tomography are usually sufficient for the diagnosis of osteoid osteoma. Initial treatment includes salicylates and NSAID because the tumor often regresses spontaneously over 2-6 years. Surgical treatment is indicated in case of unresponsive pain to medical therapy, no tolerance of prolonged NSAID therapy due to side effects, and no willingness to activity limitations. Nowadays, minimally invasive techniques have replaced open surgery and are considered the gold standard of surgical treatment. Although cryoablation seems superior in terms of the nerve damage and immunotherapy effect, radiofrequency ablation is the preferred technique.

Effectiveness and reliability of traditional open surgery in atypical localizations of osteoid osteoma

Objectives

This study aims to evaluate traditional open surgery results of osteoid osteomas (OOs) in atypical localizations and explore whether open surgery can be a safe alternative in localizations where radiofrequency ablation (RFA) may not be suitable.

Patients and methods

A total of 26 patients (20 males, 6 females; mean age 23.3±14.2 years; range, 4 to 65 years) having OO in atypical localizations between January 2008 and January 2017 were retrospectively evaluated. All patients underwent traditional open surgery under anesthesia. All patients were followed-up, and their clinical success and complications were evaluated. The pain intensity was assessed using the visual analog scale (VAS).

Results

The postoperative first year VAS score was 0.2±0.5 (range, 0-2) (p<0.005). None of the patients showed any complications. No recurrences were reported at the end of the first year. All patients were relieved from pain due to OO in atypical localizations.

Conclusion

Although RFA has been accepted as the preferred treatment for OO, traditional open surgery may still be used for OO in atypical localizations yielding perfect clinical results with fewer complications. It is a safe alternative for localizations such as carpal bones, distal ulna, hand and foot where RFA complications can be seen more frequently. In these localizations, traditional open surgery can be recommended as the first treatment choice.

Osteoid osteoma: lower back pain combined with scoliosis

Osteoid osteoma is a small benign bone tumor that is primarily localized in long bone; lumbar osteoid osteoma combined with scoliosis has rarely been reported. Here, we describe a 9-year-old boy who complained of back pain and scoliosis. He underwent nidus resection and did not experience complications or osteoid osteoma recurrence. His pain and scoliosis were relieved after the operation. The findings in this case indicate that resection of osteoid osteoma is an effective and safe method of treatment. The lumbar spine is the most common location of osteoid osteoma, which causes painful scoliosis. Nidus resection can provide relief of back pain and scoliosis.

3D imaging and stealth navigation instead of CT guidance for radiofrequency ablation of osteoid osteomas: a series of 52 patients

Background

Osteoid osteomas are benign bone neoplasms that may cause severe pain and limit function. They are commonly treated by radiofrequency ablation (RFA) through a needle inserted into the nidus of the lesion under CT guidance, which is associated with exposure of young patients to relatively high dose of radiation. The objective of this study was to investigate the amount of radiation, effectiveness and safety of an alternative imaging approach, the 3D image-guided (O-arm) technology and the Stealth navigation.

Methods

We retrospectively reviewed 52 electronic medical files of patients (mean age 24.7 years, range 8–59 years) who were treated with thermal ablation of benign osteoid osteomas guided by the navigated O-arm-assisted technique in our institution between 2015 and 2017. Data were extracted on the associated complications, the reduction in pain at 3 months and one year postoperatively, and the amount of radiation administered during the procedure.

Results

The level of pain on a visual analogue scale decreased from the preoperative average of 7.73 to 0 at the 3-month follow-up. The mean dose-length product was 544.7 mGycm² compared to the reported radiation exposure of 1971–7946 mGycm² of CT-guided radio ablations. The one intra-operative complication was a superficial burn in the subcutaneous lesion in a tibia that was treated locally with no major influence on recovery.

Conclusions

RFA ablation guided by 3D O-arm stealth navigation is as effective as the traditional CT-guided technique with the advantage of lower radiation exposure.

Trial registration

Retrospective study number 0388–17-TLV at Tel Aviv Sourasky Medical Center IRB, approved at 25.10.17.

Phase I/II Study of Radiofrequency Ablation for Painful Bone Metastases: Japan Interventional Radiology in Oncology Study Group 0208

PURPOSE

A prospective multicenter phase I/II trial was performed to evaluate the clinical safety and efficacy of radiofrequency ablation (RFA) for metastatic bone tumors.

MATERIALS AND METHODS

Thirty-three patients (27 men, 6 women, mean age 61 years) with metastatic bone tumors were enrolled. In phase I, nine patients were enrolled, and the safety of RFA was evaluated. In phase II, 23 patients were included, and an intent-to-treat analysis was performed. The primary endpoint was to evaluate the treatment's safety. The secondary endpoint was to evaluate the efficacy of pain relief at 1 week after RFA.

RESULTS

RFA was performed in 32 of 33 enrolled patients. No serious complications were observed during the phase I, so phase II was performed. Four patients exhibited adverse events, including one case each of Grade 3 pain and, Grade 2 hypotension, and one patient developed Grade 1 burns at the grounding pad and puncture site. One patient died of liver failure on day 7 after RFA due to the progression of the primary lesion. The efficacy was excellent (no increase in analgesic dosage, post-RFA VAS score of 0-2 or decreased by not less than 5 compared to before RFA) in 20 patients (60.6%), good (no increase in analgesic dosage, post-RFA VAS score decreased by not less than 2 but by < 5 compared to before RFA) in 3 (9.1%), and poor in 10 patients (30.3%). Thus, the response rate was 69.7%.

CONCLUSION

RFA is a safe and effective method for treating painful metastatic bone tumors.

Percutaneous radiofrequency ablation in osteoid osteoma: Tips and tricks in special scenarios

OBJECTIVES

To define specific characteristics of osteoid osteomas treated with radiofrequency ablation, that may benefit from special technical recommendations.

METHODS

Retrospective analysis of all radiofrequency ablations performed by our group from January 2001 to March 2015. A descriptive study was conducted. We compared our results with the available literature to determine the most frequent special scenarios.

RESULTS

207 radiofrequency ablations were performed in 200 patients. We defined the following scenarios: osteoid osteomas located in the spine, close to neurovacular structures, osteoid osteomas in small bones (hands and feet), intra-articular, deeply located or superficial and lesions with extensive periosteal reaction.

CONCLUSIONS

The scenarios defined required special considerations and technical variations. Implementing the different tips and tricks shown in the article, the most complex osteoid osteomas could be successfully ablated.

Femur shaft fracture following osteoid osteoma radiofrequency ablation

Introduction

Radiofrequency ablation is an effective modality in treating osteoid osteoma while avoiding the complications of an open procedure. Its complications are usually self-limited consisting mostly of local skin burns. This report presents a major complication, a femur shaft fracture following an osteoid osteoma radiofrequency ablation. The fracture occurred approximately one year after the ablation at the site of the osteoid osteoma.

Discussion

Few case reports have been published regarding subtrochanteric femur fracture after ablation of an osteoid osteoma. To our knowledge this is the first report of a femoral shaft fracture following an ablation. Another unique characteristic of the presented case is the late presentation, approximately one year following ablation. Factors which may have contributed to the fracture include lateral entry point of the drill which may have weakened the femur when taking its biological and mechanical properties into account, and the fact that the patient was a soldier who was allowed to continue his military training only six weeks after the ablation.

Conclusion

Radiofrequency ablation is an effective and relatively safe technique in treating osteoid osteomas, however the physician should be aware of the fracture risk involved, consider mechanical and biologic factors of the bone prior to drilling, and be very conservative when recommending return to high level activity. In addition, a close follow-up should be carried on after the procedure in order to supervise bone remodeling.

CT-guided radiofrequency ablation of osteoid osteoma using a multi-tined expandable electrode system

BACKGROUND AND AIM OF THE WORK

Radiofrequency ablation (RFA) is the gold standard for the treatment of symptomatic osteoid osteoma (OO) as RFA yields both a high success and low complication rate. It has been widely utilized over the years, but recurrences of OO after this treatment have been documented. These recurrences may be the result of various factors, including incomplete tumor ablation, and are significantly higher in lesions greater than 10 mm. Thus, the need to induce thermal ablation in a wider area led us to use a Multi-Tined Expandable Electrode System (MTEES). In this study we examined the efficacy and safety of RFA using a MTEES in symptomatic OO.

METHODS

Between January 2005 and June 2007, 16 patients with symptomatic OO were treated by CT-guided percutaneous RFA using a MTEES. The diameter of OO ranged from 6 to 15 mm (mean 10±2.6 mm). Patients were evaluated for clinical outcomes, complications and recurrence. Pain evaluation was assessed preoperatively, 2 weeks postoperatively and at last follow-up.

RESULTS

Clinical follow-up was available for all patients at a mean of 84.3 months (range 73-96 months). Mean preoperative VAS score was 7.4 (range 5-9), two weeks after the procedure mean VAS score was 0.3 (range 0-1) with a mean change of -7.06 points (p<0.0001). At the last follow-up a complete relief from pain has been observed in all patients. No major and minor complications were observed nor recurrences.

CONCLUSIONS

RFA using a MTEES has been effective, safe and reliable for the treatment of OOs. This system, by increasing the size of the necrosis, could be a viable alternative to the single needle electrode in lesions larger than 10 mm, reducing the risk of recurrence.

[The intraarticular osteoid osteoma : A diagnostic and therapeutic challenge]

Intra- and, respectively, periarticular osteoid osteoma are accompanied by sympathical arthritis which itself can irreversibly destroy the cartilage of the joint. In contrast to other locations, intra- and periarticular osteoid osteoma are rare. Reactive and symptomatic accompanying arthritis may lead to irreversible cartilage destruction especially in chronic courses. Therefore early diagnosis and therapy is crucial. We present a case report and discuss these rare tumors by reviewing the literature.

Osteoid osteoma - radiofrequency ablation treatment guided by computed tomography: a case series

The osteoid osteoma is a benign primary bone tumor that affects mainly males in the second and third decades of life. Radiographic findings show a radiolucent nidus surrounded by reactive sclerotic bone, particularly in the long bones of the lower extremity. Clinically, it presents persistent pain, which is worse at night and improves with salicylates. It can be a self-limiting injury, with an average duration of three years, but because of pain intensity and intolerance to prolonged use of nonsteroidal anti-inflammatories, surgical treatment is an option. The diagnosis is suspected according to the history and radiographic findings, and the confirmation is made by histological analysis. The traditional surgical treatment is the complete excision of the nidus, but some disadvantages have been described, such as difficulties in localizing the lesion and risk of fracture during the procedure, hospital stay for pain control, and unfavorable esthetic outcome. The authors report a series of cases treated with thermal radiofrequency ablation guided by computed tomography in this service. It is a safe and an effective percutaneous method that aims to cure, minimizing the trauma and morbidity when compared with the conventional block-resection method.

A large osteoid osteoma of the mandibular condyle causing conductive hearing loss: a case report and review of literature

Osteoid osteomas are benign skeletal neoplasms that are commonly encountered in the bones of the lower extremities, but are exceedingly rare in jaw bones with a prevalence of less than 1%. This unique clinical entity is usually seen in younger individuals, with nocturnal pain and swelling as its characteristic clinical manifestations. The size of the lesion is rarely found to be more than 2 cm. We hereby report a rare case of osteoid osteoma originating from the neck of the mandibular condyle that grew to large enough proportions to result in conductive hearing loss in addition to pain, swelling and restricted mouth opening. In addition, an effort has been made to review all the documented cases of osteoid osteomas of the jaws that have been published in the literature thus far.

Remodeling of the Cervical Facet Joint After Minimally Invasive Microendoscopic Resection for Cervical Osteoid Osteoma

STUDY DESIGN

Case report and systematic review of the literature.

OBJECTIVE

To describe a rare case of remodeling of the cervical facet joint after the microendoscopic resection of an osteoid osteoma.

SUMMARY OF BACKGROUND DATA

Osteoid osteoma, the third most common benign bone tumor, is often treated by image-guided percutaneous removal of the nidus. However, percutaneous resection poses technical difficulties when the tumor is located near the spinal cord or nerve roots. To our knowledge, there are no reports describing postoperative remodeling of the cervical facet joint after surgical resection of an osteoid osteoma.

METHODS

A 13-year-old boy was presented with neck pain that became worse at night. Computed tomography showed an osteoid osteoma in the right 7th cervical superior articular process. We successfully resected the nidus of the osteoid osteoma using minimally invasive microendoscopy.

RESULTS

The patient was symptom-free at the 1-year follow up, and computed tomography images showed new bone formation at the C6/7 facet joint.

CONCLUSION

This case indicates that microendoscopic resection is safe and effective for treating a cervical osteoid osteoma. This technique allowed total resection of the nidus with only minimal damage to the adjacent soft tissue and bone, and induced remodeling of the resection site.Level of Evidence: 4.

Long-term clinical outcomes of dual-cycle radiofrequency ablation technique for treatment of osteoid osteoma

PURPOSE

Radiofrequency ablation technique for treatment of OO including ablation time and temperature vary greatly between and within reported studies. This study evaluates the immediate and long-term efficacy and complication rate of a two sequential RFA technique for OO.

MATERIALS AND METHODS

We retrospectively reviewed medical records and attempted interview follow-up for 25 patients treated with RFA for OO. Each treatment included 2 consecutive RFAs at 90 °C for 6 min with inter-ablation cooling to 40 °C and occasional inter-ablation probe adjustment. Additionally, we statistically compared the proportion of successful ablations using the DCRFA technique with published studies that utilized alternative OO ablation procedures.

RESULTS

Long-term follow-up was obtained for 24 patients (96 %). Mean patient age at DCRFA was 17.2 years (range, 2.2-50.0 years). Mean time to follow-up was 60 ± 42 months (range 12-152 months). No acute DCRFA-related complications nor long-term recurrences were reported. All 24 interviewed patients reported partial relief of pre-procedural pain within 1 day of DCRFA and total relief within 1 week of DCRFA. One patient ultimately developed a major late complication (complex regional pain syndrome of the left ankle) after DCRFA of a cuboid lesion. Additionally, the DCRFA success rate was significantly higher when compared to two other published OO RFA treatment results.

CONCLUSION

DCRFA employing two sequential 6-min cycles is an effective treatment of OO. The 100 % primary success rate, 0 % long-term recurrence rate, and low complication rate compare favorably and may be superior to results of prior reports.

Osteoid osteoma presenting as thoracic scoliosis

BACKGROUND CONTEXT

Osteoid osteoma of the thoracic spine is relatively uncommon and is often difficult to diagnose, especially when patients do not complain of pain.

PURPOSE

This study aims to describe an unusual case of scoliosis caused by osteoid osteoma of the thoracic spine that was challenging to diagnose.

STUDY DESIGN/SETTING

A case report of a 12-year-old girl who presented with scoliosis caused by osteoid osteoma of the thoracic spine without apparent pain was carried out.

METHODS

Diagnosis of the lesion was made using computed tomography (CT) and magnetic resonance imaging as well as the Scoliosis Research Society-22 (SRS-22) patient-based questionnaire.

RESULTS

A preoperative CT myelogram revealed a mass lesion in the lamina of the 10th thoracic vertebra that was considered to be osteoid osteoma. This diagnosis was histologically confirmed following tumor excision. The patient's spinal deformity and SRS-22 scores were both improved at 5 months postoperatively.

CONCLUSIONS

Osteoid osteoma of the thoracic spine may present as non-painful scoliosis. Tumor resection is effective. Clinicians should bear this uncommon lesion in mind during recommended CT examination before scoliosis surgery.

Paediatric musculoskeletal interventional radiology

Interventional radiology technique is now well established and widely used in the adult population. Through minimally invasive procedures, it increasingly replaces surgical interventions that involve higher percentages of invasiveness and, consequently, of morbidity and mortality. For these advantageous reasons, interventional radiology in recent years has spread to the paediatric age as well. The aim of this study was to review the literature on the development, use and perspectives of these procedures in the paediatric musculoskeletal field. Several topics are covered: osteomuscle neoplastic malignant and benign pathologies treated with invasive diagnostic and/or therapeutic procedures such as radiofrequency ablation in the osteoid osteoma; invasive and non-invasive procedures in vascular malformations; treatment of aneurysmal bone cysts; and role of interventional radiology in paediatric inflammatory and rheumatic inflammations. The positive results that have been generated with interventional radiology procedures in the paediatric field highly encourage both the development of new ad hoc materials, obviously adapted to young patients, as well as the improvement of such techniques, in consideration of the fact that childrens' pathologies do not always correspond to those of adults. In conclusion, as these interventional procedures have proven to be less invasive, with lower morbidity and mortality rates as well, they are becoming a viable and valid alternative to surgery in the paediatric population.

Osteoid osteoma treated with radiofrequency ablation

Purpose. Our aim is to evaluate the results of treatment with computed tomography (CT) guided percutaneous radiofrequency ablation for osteoid osteomas which were localized in a difficult area for operation. Materials and Methods. Glenoid, distal tibia, humerus shaft, proximal humerus, and in third finger of the hand proximal phalanx were involved in one patient. Proximal femur was involved in three patients, distal femur was involved in three patients, and proximal tibia was involved in two patients. 9 males and 4 females were aged 4 to 34 years (mean age: 18.5 years). All patients had pain and were evaluated with X-rays, CT, bone scintigraphy, and MRI. In all patients, RF ablation was performed with local anesthesia. The lesion heated to 90°C for 6 minutes. Results. All of the patients achieved complete pain relief after ablation and were fully weight bearing without any support. In all patients, there was soft tissue edema after the procedure. During follow-up, all patients were free from the pain and there was no sign about the tumor. There was no other complication after the process. Conclusion. CT guided RFA is a minimally invasive, safe, and cost-effective treatment for osteoid osteoma placed in difficult area for surgery.

Percutaneous image-guided ablation of bone and soft tissue tumours: a review of available techniques and protective measures

Background

Primary or metastatic osseous and soft tissue lesions can be treated by ablation techniques.

Methods

These techniques are classified into chemical ablation (including ethanol or acetic acid injection) and thermal ablation (including laser, radiofrequency, microwave, cryoablation, radiofrequency ionisation and MR-guided HIFU). Ablation can be performed either alone or in combination with surgical or other percutaneous techniques.

Results

In most cases, ablation provides curative treatment for benign lesions and malignant lesions up to 3 cm. Furthermore, it can be a palliative treatment providing pain reduction and local control of the disease, diminishing the tumour burden and mass effect on organs. Ablation may result in bone weakening; therefore, whenever stabilisation is undermined, bone augmentation should follow ablation depending on the lesion size and location.

Conclusion

Thermal ablation of bone and soft tissues demonstrates high success and relatively low complication rates. However, the most common complication is the iatrogenic thermal damage of surrounding sensitive structures. Nervous structures are very sensitive to extremely high and low temperatures with resultant transient or permanent neurological damage. Thermal damage can cause normal bone osteonecrosis in the lesion’s periphery, surrounding muscular atrophy and scarring, and skin burns. Successful thermal ablation requires a sufficient ablation volume and thermal protection of the surrounding vulnerable structures.

Teaching points

• Percutaneous ablations constitute a safe and efficacious therapy for treatment of osteoid osteoma.

• Ablation techniques can treat painful malignant MSK lesions and provide local tumour control.

• Thermal ablation of bone and soft tissues demonstrates high success and low complication rates.

• Nerves, cartilage and skin are sensitive to extremely high and low temperatures.

• Successful thermal ablation occasionally requires thermal protection of the surrounding structures.

Percutaneous CT-guided radiofrequency thermocoagulation in the treatment of osteoid osteoma: a 87 patient series

INTRODUCTION

Osteoid osteoma is a painful, benign bone tumor that mainly affects young people. Thermocoagulation is one of the recommended percutaneous treatment methods. This study sought to assess its efficacy and identify risk factors for osteoma recurrence.

METHODS

Results were analyzed retrospectively for a group of 87 patients treated by thermocoagulation between 2002 and 2011. The recurrence rate was calculated and analyzed relative to patient and tumor characteristics. The treatment efficacy was determined and methods to prevent complications were analyzed.

RESULTS

The mean follow-up time was 34 months. The average patient age was 23 years. There were seven complications including three patients with delayed wound healing, mainly at tibial sites. The recurrence rate was 10.4%. The success rate for first-line treatment was 89.6% and it was 97.5% for second-line treatment. Analysis of patient characteristics and tumor locations revealed no risk factors for recurrence.

CONCLUSION

Percutaneous thermocoagulation is a reliable and effective technique that provides fast, long-lasting pain relief. However recurrence can occur even after the nidus is completely resected. These recurrences can be effectively managed by repeat treatment. Recent technical improvements have reduced the risk of thermocoagulation-related complications.

LEVEL OF EVIDENCE

IV.

Efficacy of magnetic thermoablation using SPIO in the treatment of osteoid osteoma in a bovine model compared to radiofrequency and microwave ablation

PURPOSE

To evaluate heating efficacy of superparamagnetic iron oxide nanoparticles (SPIO) for electromagnetic ablation (EMA) of osteoid osteoma (OO) using an ex vivo model compared to radiofrequency ablation (RFA) and microwave ablation (MWA).

METHODS

A model for OO using sliced bovine tibia and sliced muscle tissue was developed. A bone cavity filled with either a mixture of SPIO and agarose or pure agarose (control group) was established. EMA was performed using an experimental system, RFA and MWA using clinically approved systems, and the ablation protocols recommended by the vendor. For temperature measurements, fiberoptic temperature probes were inserted inside the cavity, on the outside of the periosteum, and at a 5 mm distance to the periosteum.

RESULTS

Maximum temperatures with or without SPIO in the nidus were as follows: EMA: 79.9 ± 2.5/22.3 ± 0.7 °C; RFA: 95.1 ± 1.8/98.6 ± 0.9 °C; MWA: 85.1 ± 10.8/83.4 ± 9.62 °C. In RFA with or without SPIO significantly higher temperatures were achieved in the nidus compared to all other groups (p < 0.05). In MWA significantly higher temperatures were observed in the 5 mm distance to the periosteum compared to EMA and RFA with or without SPIO (p < 0.05). In MWA temperature decrease between nidus and the 5 mm distance to the periosteum was significantly lower than in RFA with or without SPIO (p < 0.0001). In MWA without SPIO temperature decrease was significantly lower than in the EMA group (p < 0.05).

CONCLUSION

In the experimental setting, ablation of OO is safe and effective using EMA. It is less invasive than RFA and MWA, and it theoretically allows repeated treatments without repeated punctures. In comparison, the highest temperatures in the nidus are reached using RFA.

Osteoid osteoma treated by percutaneous thermal ablation: when do we fail? A systematic review and guidelines for future reporting

PURPOSE

Osteoid osteoma (OO) is a painful benign bone tumor of the young that is widely treated by percutaneous thermal ablation (PTA) with success rates close to 100%. Nevertheless, some patients have recurrences. We reviewed the literature to understand whether these are true recurrences or incomplete treatments; to analyze safety and efficacy during long-term follow-up in a extremely large cohort of patients; to detail best-practice suggestions from the largest clinical trials as well as report their complications; and to recommend standards for future reporting.

MATERIALS AND METHODS

This study followed the Cochrane's guidelines for Systematic Reviews of Interventions. Inclusion criteria were as follows: (1) prospective or retrospective cohort study for PTA of OO under computed tomography (CT) guidance; (2) CT or magnetic resonance diagnosis; (3) radiofrequency ablation or interstitial laser ablation technique; (4) English language; (5) population <10 patients; (6) follow-up ≥12 months; and (7) original research. Risk of bias was assessed with a modified Newcastle-Ottawa Scale.

RESULTS

Two hundred fourteen articles were initially found. After applying the criteria mentioned previously, 27 PTA articles concerning 1,772 patients were chosen for inclusion. No exclusions were made due to risk of bias.

CONCLUSION

The investigators proved the long-term efficacy and superiority of PTA for OO compared with other techniques. In 5% of patients, however, the technique failed, and the researchers did not offer detailed exhaustive explanations. Future clinical trials for OO ablation should consider reporting essential procedure details and follow-up findings to allow for a meta-analysis. We provide both recommended standards for future reporting and suggestions for the prevention of recurrence.

Microendoscopic excision of C2 osteoid osteoma: a technical report

STUDY DESIGN

Case report and description of technique.

OBJECTIVE

To describe a microendoscopic posterior approach for excision of an osteoid osteoma of C2.

SUMMARY OF BACKGROUND DATA

Microendoscopic techniques are widely used in the management of degenerative disorders of the spine. This is the first report of their use in the management of an osteoid osteoma via the posterior approach.

METHODS

A 12-year-old-boy presented with left-sided neck pain of 3-month duration. Investigations revealed an osteoid osteoma of C2 lamina-lateral mass complex. The patient underwent a posterior microendoscopic excision using 18-mm diameter METRx system (Medtronic Sofamor Danek, Memphis, TN) of tubular retractors. A postoperative computed tomographic scan was done and preoperative and postoperative visual analogue scale and Neck Disability Index were evaluated. The patient was periodically followed up for 1 year.

RESULTS

The postoperative computed tomographic scan revealed complete excision of the tumor. The visual analogue scale score for neck pain improved from 3/5 (preoperative) to 0/5 (postoperative) and Neck Disability Index from 33.33 (preoperative) to 0 (postoperative) at 1-year follow-up.

CONCLUSION

Microendoscopic techniques can be extended to excise lesions of the spine. It is a safe procedure in experienced hands. The advantages are minimal morbidity, minimal postoperative pain and discomfort, less analgesic dependence, and better cosmesis. The authors recommend this technique for accessible lesions involving the spine.

Percutaneous navigation surgery of osteoid osteoma of the femur neck

Surgery on benign bone tumors such as osteoid osteoma does not necessarily require bone exposure through a surgical incision. In most reported cases of the osteoid osteoma resection through computer-assisted surgery, registration and surgery were performed by exposing the bone. We have succeeded in performing percutaneous registration and navigated burr excision of the osteoid osteoma using computer-assisted navigation.

Treatment of osteoid osteoma with CT-guided percutaneous radiofrequency thermoablation

Osteoid osteoma is a benign bone tumor with a male predominance occurring mainly in children and young adults. The most common symptom is intermittent pain that worsens at night and is at least partially relieved by nonsteroidal anti-inflammatory drugs. The purpose of this study was to assess the long-term effectiveness of computed tomography-guided percutaneous radiofrequency thermoablation in patients with a minimum follow-up of 2 years. Twenty patients with osteoid osteoma (15 men and 5 women) with a mean age of 20.7 years (range, 4-61 years; 12 patients aged 20 years or younger) underwent computed tomography-guided percutaneous radiofrequency thermoablation. Lesion sites were the femur (n=9), tibia (n=7), pelvis (n=1), talus (n=1), cuneiform bone (n=1), and humerus (n=1). Mean follow-up was 44 months (range, 3-106 months). Pain relief was significant in 95% of patients; it disappeared within 24 hours in 14 patients, within 3 days in 4, and within 7 days in 1. The patient with persistent symptoms underwent another percutaneous radiofrequency thermoablation procedure that was successful. The difference between pre- and postoperative pain was significant (P ≤ .01). No recurrences occurred. Computed tomography-guided percutaneous radiofrequency thermoablation is a safe, minimally invasive, and economical procedure with high technical and clinical success rates, and it effectively and durably enhances quality of life.

Radiofrequency ablation of osteoid osteoma: outcomes from the West of Scotland

Background

Osteoid osteoma is a classically described benign bone tumour. Traditionally, the surgical treatment of choice was excision, but this can have significant morbidity. Percutaneous radiofrequency ablation (RFA) has grown in popularity as an alternative treatment. This study reports the outcomes using this technique in our regional bone tumour unit.

Methods

Between May 2003 and October 2007, 14 patients underwent CT-guided RFA. All patients were subsequently offered follow-up in the out-patient clinic. Outcomes were taken from the Scottish Bone Tumour Registry database.

Results

Eleven patients (78.6%) had complete resolution of symptoms after one RFA. Three (21.4%) cases were unsuccessful but one of these was due to technical failure. All three of the above patients had complete relief of symptoms after one further RFA. One (7.1%) patient initially had complete relief of symptoms, but suffered recurrence after 9 months. This patient also had a second curative treatment.

Conclusion

Percutaneous RFA for osteoid osteoma is an attractive treatment due to its efficacy and low morbidity. Our results showed a primary success rate of 78.6%, a secondary success rate of 100% (after one additional procedure). Our results add to the growing literature supporting RFA as the preferred treatment for osteoid osteoma.

Case report: Osteoid osteoma of the acetabulum treated with arthroscopy-assisted radiofrequency ablation

BACKGROUND

Osteoid osteomas consist of a nidus surrounded by reactive sclerotic bone. The diagnosis typically is based on imaging and clinical presentation involving nocturnal pain. Removal of the lesion is essential and currently is performed mainly with image-guided, minimally invasive techniques. We describe a case involving an osteoid osteoma of the acetabular fossa, treated with arthroscopy-assisted radiofrequency ablation.

CASE DESCRIPTION

A 47-year-old woman presented with a 9-month history of right groin pain and limited motion. The CT and MR images showed synovitis around the ligamentum teres and a nidus of the acetabular fossa, surrounded by sclerotic bone and protruding from the inner part of the lamina quadrilateral. Synovectomy and debridement of the ligamentum teres were performed, followed by radiofrequency ablation of the osteoid osteoma under direct arthroscopic observation of the hip, avoiding resection of the normal bone around the nidus and preserving the integrity of the quadrilateral lamina and cartilage. The patient had complete pain relief the next day with minimal morbidity and rapid functional restoration. At the 22-month clinical followup, the patient was asymptomatic, and the CT and MR images obtained 1 year after surgery showed no pathologic signs or synovitis.

LITERATURE REVIEW

Our case was the fifth such case to be treated with hip arthroscopy and the first of these to our knowledge to be treated with the arthroscopy-assisted radiofrequency ablation technique.

PURPOSES AND CLINICAL RELEVANCE

Arthroscopy-assisted radiofrequency ablation is a combined treatment technique that may be used for intraarticular lesions of the hip that otherwise would require a difficult approach and jeopardize damage to cartilage and bone and also treat concomitant synovitis.

Radiofrequency ablation in experimental bone metastases using a controlled and navigated ablation device

BACKGROUND

Radiofrequency ablation is a minimal invasive therapy in the treatment of bone metastases. In this study we present a new ablation system enabling an ablation in multiple directions and with an adaptable size and shape.

MATERIAL AND METHODS

VX-2 tumor was used for the induction of experimental bone metastases in the femur of six New Zealand white rabbits. X-ray imaging as well as CT and MRI scans before and after treatment was carried out. After detecting bone tumor, radiofrequency ablation was performed. The ablation instrument contained a 10 g bipolar, articulated extendable electrode and a proprietary generator with an impedance controlled algorithm. All bones and the soft tissue were examined histologically.

RESULTS

All animals developed local bone tumor. Mean duration until first osteolytic lesions on CT-scans was 48±14 days. The mean lesion area was 26 mm(2). No systemic tumor spread was seen. 6 radiofrequency procedures were carried out with a mean application time of 6 min±2:30 and an average temperature in the region of effect of 55 °C±4. MRI imaging demonstrated an ablation zone of 23±6 mm around the electrode. Histopathology showed an extensive heat necrosis with no remaining tumor cells in the ablation area.

CONCLUSION

Radiofrequency ablation is a quickly developing treatment option on the field of minimal invasive bone tumor therapy. The electrode enables an ablation adapted to size and shape of the metastases. Further clinical studies are necessary to test and enhance this radiofrequency system.

Osteoid osteoma: can impedance levels in radiofrequency thermocoagulation predict recurrence?

Objective. To evaluate rise in impedance during percutaneous radiofrequency thermocoagulation (PRFTC) of osteoid osteomas as a predictor of local recurrence. Design and Patients. A prospective study of 23 patients (24 PRFTC procedures) with minimum of 2.25-year followup (average 3.3 years). Average age 19.6 years (range 4–44), sex ratio 15 : 8 (male : female), 16 nondiaphyseal, 7 diaphyseal. Results. In 19 procedures, an increase in impedance was measured—no recurrences have occurred in this group to date. In 5 procedures, no increase in impedance was seen (3 non-diaphyseal, 2 diaphyseal), and 1 recurrence has been seen in this group to date. This difference is statistically significant with a P value of .05.

Radiofrequency ablation for non-spinal osteoid osteomas in 557 patients

OBJECTIVES

To present the results of biopsy and computed tomography (CT) guided radiofrequency ablation (RFA) for non-spinal osteoid osteomas, and compare the results before and after procedural modifications.

METHODS

We retrospectively studied 557 patients with non-spinal osteoid osteomas treated with biopsy and CT-guided RFA. In 68 patients we used 3-mm CT at 2-mm intervals, 19 G/5-mm active tip electrodes, and one 4-minute ablation at 90-93°C. In 489 patients we used contiguous 1-mm CT, 20 G/5-15-mm electrodes, ablation maintaining 60°C for 2 min followed by 14-15 min at 90-93°C, and multiple ablations in the same session for large and multiform lesions.

RESULTS

533/557 patients (96%) remained asymptomatic and 24/557 (4%) had recurrence; repeat RFA was successful in 22/24 patients (92%). Biopsy was non-diagnostic in 82%. With the modifications performed, success improved from 79% to 98%, recurrences reduced from 21% to 2% and complications from 5.9% to 0.2% (p < 0.001). All patients with large and multiform lesions treated with one ablation had recurrence, compared to no patient with similar lesions and multiple ablations in the same session.

CONCLUSION

Electrode parameters, duration of ablation, morphology and size of osteoid osteomas are important for RFA. The above modifications are recommended for improved outcome.

Percutaneous radiofrequency ablation for osteoid osteoma: How we do it

AIMS AND OBJECTIVES

To describe our technique for performing radiofrequency ablation (RFA) in osteoid osteoma and to evaluate the results of treatment.

MATERIALS AND METHODS

We evaluated 40 patients in whom RFA was performed for osteoid osteomas between October 2005 and February 2008. The lesions were located in the femur (n = 22), tibia (n = 10), humerus (n = 2), acetabulum (n = 2), radius (n = 1), fibula (n = 1), patella (n = 1), and calcaneum (n = 1). The procedure was performed using a standard technique.

RESULTS

Technical success was achieved in all patients, with intranidal localization of the needle and complete ablation. All patients were fully weight bearing 2-3 h after the procedure. Successful pain relief was achieved in all patients within 48 h. Immediate complications included a case of minor thermal skin burn and a small cortical chip fracture, which healed on its own. There were no delayed complications. The average follow-up period was 12 months. Two patients (5% of cases) had recurrence of pain after intervals of 5 and 8 months, respectively, following the ablation; this was due to recurrence of the lesion. Complete pain relief was however achieved after a second ablation in both cases. Thus, our primary and secondary clinical success rates were 95 and 100%, respectively.

CONCLUSION

RFA is a safe, quick, minimally invasive, and extremely effective method for the management of osteoid osteomas.

Therapeutic response to radiofrequency ablation of neoplastic lesions: FDG PET/CT findings

Ablation of neoplastic lesions by using radiofrequency energy is gaining popularity in clinical practice because of the minimally invasive nature of radiofrequency ablation (RFA). Primary and secondary tumors of the liver and lung are treated with RFA when surgery is precluded because of comorbidity. Benign bone tumors are also treated with RFA to relieve pain and prevent further tumor growth. Differentiation between postablation tissue changes and residual disease is difficult with morphologic imaging modalities such as ultrasonography, computed tomography (CT), and magnetic resonance (MR) imaging, thus limiting the use of these modalities to detection of residual disease early after RFA. Fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) is a functional imaging modality that can be used to study the effects and efficacy of RFA. Lesions that show increased FDG uptake at PET become completely photopenic immediately after RFA, a finding that is suggestive of the completeness of ablation. Focal areas of increased FDG uptake within the ablated zone are suggestive of residual disease. Reactive tissue changes such as inflammation are depicted in the periphery of the ablated lesion and show a uniform low-grade FDG uptake, which can be differentiated from the focal, nodular intense uptake in areas of residual disease. Use of combined FDG PET/CT to detect residual disease early after RFA allows ablation to be repeated, if necessary, to obtain the maximum therapeutic benefit. Note that FDG uptake in the complications sometimes associated with RFA can be a cause of potential false-positive PET results.

Osteoid osteoma of the femoral head treated by radiofrequency ablation: a case report

Introduction

We present a case report highlighting the unusual location and atypical imaging characteristics of an osteoid osteoma in the juxta-articular region of the femoral head, and treatment of the condition with radiofrequency ablation. This treatment option is low in both risk and morbidity and is therefore the best option in lesions that are difficult to access surgically because of the risks involved.

Case presentation

A 40-year-old Indian man from West Bengal presented to our facility with a history of progressively severe left hip pain of insidious onset, requiring analgesics. Imaging with plain radiographs, computed tomography and magnetic resonance imaging confirmed findings of osteoid osteoma in a subarticular location in the femoral head, although imaging features were atypical due to the intra-articular subchondral location.

Conclusion

Radiofrequency ablation is a newer treatment modality for osteoid osteoma that, being minimally invasive, offers comparable results to surgery with a significantly lower morbidity. To the best of our knowledge, treatment of osteoid osteoma in the foveal region of the femoral head with radiofrequency ablation has not been reported to date. We wish to highlight the successful outcome in our index case using this technique.

Osteoid osteoma near the intervertebral foramen may induce radiculopathy through tumorous inflammation

Osteoid osteoma of the spine is a relatively rare bone-forming tumor. Pain that is worse at night and relieved by aspirin and muscle contracture are the most characteristic symptoms of spinal osteoid osteoma. Although radicular pain occasionally occurs in spinal osteoid osteoma, spinal cord and nerve root compression is absent in most cases. Although radicular pain appears to be associated with tumorous inflammation, there have been no presentations of histological findings of inflammation around the nerve root. We present here two rare cases of spinal osteoid osteoma causing radiculopathy and the first histological evidence of tumorous inflammation as a cause of radiculopathy in osteoid osteoma near the intervertebral foramen.

Percutaneous radiofrequency ablation of osteoid osteomas with use of real-time needle guidance for accurate needle placement: a pilot study

PURPOSE

To evaluate the accuracy and technical success of positioning a radiofrequency ablation (RFA) electrode in osteoid osteomas by use of a new real-time needle guidance technology combining cone-beam computed tomography (CT) and fluoroscopy.

MATERIALS AND METHODS

Percutaneous RFA of osteoid osteomas was performed in five patients (median age 18 years), under general anesthesia, with the use of cone-beam CT and fluoroscopic guidance for electrode positioning. The outcome parameters were technical success, meaning correct needle placement in the nidus; accuracy defined as the deviation (in mm) from the center of the nidus; and clinical outcome at follow-up.

RESULTS

In all five cases, positioning was possible within 3 mm of the determined target location (median nidus size 6.8 mm; range 5-10.2 mm). All procedures were technically successful. All patients were free of pain at clinical follow-up. No complications were observed.

CONCLUSION

Real-time fluoroscopy needle guidance based on cone-beam CT is a useful tool to accurately position radiofrequency needles for minimally invasive treatment of osteoid osteomas.

Radiofrequency ablation of osteoid osteoma in atypical locations: a case series

BACKGROUND

Osteoid osteoma has a nidus surrounded by sclerotic bone with a size usually less than 20 mm. Its diagnosis is made on typical presentation of nocturnal pain and imaging findings. Excision of the niduses, which are often small and difficult to precisely identify, sometimes may result in resection of surrounding normal bone. Minimally invasive percutaneous treatments have been used to try to minimize resection of normal bone. Although minimally invasive radiofrequency ablation generally relieves pain, its ability to relieve pain is less well known in locations other than lower extremity long bones.

QUESTIONS/PURPOSES

We determined the pain relief and complication rates after radiofrequency ablation of osteoid osteomas presenting in atypical locations and followed patients to assess possible recurrence or late complications.

PATIENTS AND METHODS

We retrospectively reviewed 21 patients with osteoid osteomas in unusual locations (eg, hip, radioulnar joint, and proximal phalanx) in whom we used radiofrequency ablation. Postoperative activities were not restricted for any of the patients. We assessed the time for patients to become symptom free, their activity status, and possible recurrence or complications. The minimum clinical followup was 12 months (mean, 27.8 months; range, 12-37 months).

RESULTS

All patients became symptom free within 24 hours to 1 week. During followup, none of the patients experienced recurrence or any major complications.

CONCLUSIONS

Radiofrequency ablation for osteoid osteomas in unusual locations reliably relieves pain with few complications and recurrences at short-term followup.

LEVEL OF EVIDENCE

Level IV, case series. See Guidelines for Authors for a complete description of level of evidence.

Osteoid osteomas in common and in technically challenging locations treated with computed tomography-guided percutaneous radiofrequency ablation

OBJECTIVE

To evaluate the efficacy of computed tomography (CT)-guided radiofrequency (RF) ablation for the treatment of osteoid osteomas in common and in technically challenging locations.

MATERIALS AND METHODS

Twenty-three patients with osteoid osteomas in common (nine cases) and technically challenging [14 cases: intra-articular (n = 7), spinal (n = 5), metaphyseal (n = 2)] positions were treated with CT-guided RF ablation. Therapy was performed under conscious sedation with a seven-array expandable RF electrode for 8-10 min at 80-110 degrees C and power of 90-110 W. The patients went home under instruction. A brief pain inventory (BPI) score was calculated before and after (1 day, 4 weeks, 6 months and 1 year) treatment.

RESULTS

All procedures were technically successful. Primary clinical success was 91.3% (21 of total 23 patients), despite the lesions' locations. BPI score was dramatically reduced after the procedure, and the decrease in BPI score was significant (P < 0.001, paired t-test; n-1 = 22) for all periods during follow up. Two patients had persistent pain after 1 month and were treated successfully with a second procedure (secondary success rate 100%). No immediate or delayed complications were observed.

CONCLUSION

CT-guided RF ablation is safe and highly effective for treatment of osteoid osteomas, even in technically difficult positions.

Role of intraoperative 3D C-arm-based navigation in percutaneous excision of osteoid osteoma of long bones in children

Failures of treatment of osteoid osteoma (OO) are related to errors in exact localization and incomplete excision of the nidus. We report the successful percutaneous excision of OO in five patients (upper end of femur - 3, tibia - 2). All patients had a minimally invasive reflective array fixed to the same bone followed by registration of anatomy by Iso-C three-dimensional (3D) C-arm. A tool navigator was used to plan the keyhole incision then a sleeve was introduced which allowed the usage of burr and curette to remove the tumor. After excision, the 3D C-arm was again used intraoperatively to confirm the complete eradication of the nidus. Adequate material for histology was obtained in four patients that confirmed the diagnosis of OO. In one child postexcision scans were successful in identifying incomplete removal requiring further excision of the nidus. All patients achieved excellent pain relief and were asymptomatic at an average follow-up of 3.2 years. 3D C-arm-based navigation offers the advantage of excellent localization, percutaneous excision, and intraoperative confirmation of adequate excision.