[Challenges to endoprosthetic reconstruction after tumor resection around the knee : Management of intra- and postoperative complications]. / Herausforderungen in der Tumorendoprothetik des Kniegelenks : Management von intra- und postoperativen Komplikationen.

BACKGROUND: The good functional outcomes of endoprosthetic knee reconstructions combined with modern oncosurgical concepts have resulted in a decreased rate of primary amputations following tumor resection in the region of the knee, thereby improving the quality of life of affected patients. OBJECTIVE: This study aimed to reappraise complications which are more common than in conventional arthroplasties performed for arthritis or trauma due to the complexity of the surgical procedures, the size of the endoprosthetic reconstructions, and neo-/adjuvant therapies. MATERIAL AND METHODS: Possible intra- and postoperative complications and treatment options are presented. RESULTS: Typical intraoperative complications include malalignment (axis, length, rotation) in implant positioning, unplanned soft tissue defects, impaired implant fixation due to poor bone stock, periprosthetic fractures, vessel/nerve injuries, and lesions/defects of the extensor mechanism. The relevant postoperative complication profile is characterized by local recurrences, periprosthetic infections, thromboembolic events, and mechanical failures (loosening, failure of the constraining mechanism). CONCLUSION: Depending on anatomic conditions and the systemic oncological status of the patient, these complications represent tremendous challenges to reconstructive management. Knowledge of the potential problems enables them to be avoided. This requires profound experience in oncosurgery and tumor endoprosthesis revisions.

Skeletal metastatic disease of the femur: results by management with intramedullary nailing.

PURPOSE OF THE STUDY This study aimed to analyse the outcome following intramedullary nailing for metastases of the femur in a large cohort with special regard to mechanical, implant associated complications and patient survival. Furthermore, we aimed to identify factors influencing the overall survival. MATERIAL AND METHODS All patients (n = 74) that underwent intramedullary nailing for metastatic disease of the femur between 2004 and 2008 and were retrospectively reviewed. Data were recorded from the patients' medical record and the outpatients' clinics files. Details about the tumour biology, the surgery performed as well as the postoperative care were documented. Survival data were extracted from patient records or obtained via communication with outpatient oncologists or the community registration office. RESULTS 74 (28 (37.8%) male, 46 (62.2%) female; p = 0.048) patients with a mean age of 64.4 ± 11.7 years were included. Breast (25, 33.8%), lung (18, 24.3%), bone marrow (7, 9.5%) and kidney (6, 8.1%) were the primary tumours in more than 75% of all patients. The mean overall survival was 17.5 (95% CI: 9.6 - 25.5) months. Patients with osseous metastases had a significant longer survival than patients with visceral and/or cerebral metastases (p = 0.025 and p = 0.032). CONCLUSION Intramedullary nailing represents a valuable fixation method for pathologic fractures or impending fractures of the femur in patients with an advanced stage of metastatic disease. It provides adequate stability to outlast the patient s remaining life-span. However, the balance must be found between therapeutic resignation and surgical overtreatment since operative treatment may be accompanied with serious complications. Key words: bone metastases, intramedullary nailing, metastatic disease, cement augmentation, osteolytic defect.

[Benign cystic bone lesions]. / Benigne zystische Knochenläsionen.

BACKGROUND: Bone cysts are benign tumor-like lesions which often present as a fluid-containing cavity in the bone. They can occur in the skeletal bone as solitary or sometimes multiple bone lesions. OBJECTIVES: This review discusses the diagnostics, radiological appearance and therapeutic strategies of the most important benign cystic bone lesions, such as simple bone cysts, aneurysmal bone cysts, intraosseous ganglia, epidermoid cysts and subchondral cysts. The differential diagnoses with respect to cystoid formations and tumors with cystic components are discussed. METHOD: A selective literature search was performed taking own experiences into consideration. RESULTS: These tumor-like lesions can have the radiological appearance of bone tumors but show no autonomic, stimulus-independent growth and can resolve spontaneously. In the majority of cases open biopsy is necessary to confirm the diagnosis. In some cases no surgical intervention is necessary (e.g. do not touch and leave me alone lesions), whereas in other cases the focus of treatment is on the prevention and therapy of pathological fractures as well as prevention of recurrence. CONCLUSION: Cystic bone formations are among the most commonly occurring non-traumatic bone lesions. To eliminate differential diagnostic unclarity, histological investigation of biopsy material is essential. In terms of surgical intervention there exists a trend towards multimodal therapy mostly based on a meticulous curretage.

Postinterventional MRI findings following MRI-guided laser ablation of osteoid osteoma.

OBJECTIVE: To evaluate postinterventional magnetic resonance imaging (MRI) characteristics following MRI-guided laser ablation of osteoid osteoma (OO). MATERIALS AND METHODS: 35 patients treated with MRI-guided laser ablation underwent follow-up MRI immediately after the procedure, after 3, 6, 12, 24, 36, and up to 48 months. The imaging protocol included multiplanar fat-saturated T2w TSE, unenhanced and contrast-enhanced T1w SE, and subtraction images. MR images were reviewed regarding the appearance and size of treated areas, and presence of periablation bone and soft tissue changes. Imaging was correlated with clinical status. RESULTS: Mean follow-up time was 13.6 months. 28/35 patients (80%) showed a postinterventional "target-sign" appearance consisting of a fibrovascular rim zone and a necrotic core area. After an initial increase in total lesion diameter after 3 months, a subsequent progressive inward remodeling process of the zonal compartments was observed for up to 24 months. Periablation bone and soft tissue changes showed a constant decrease over time. MR findings correlated well with the clinical status. Clinical success was achieved in 32/35 (91%). CONCLUSIONS: Evaluation of long-term follow-up MRI after laser ablation of OO identified typical postinterventional changes and thus may contribute to the interpretation of therapeutic success and residual or recurrent OO in suspected cases.

[Management of complications following resection and defect reconstruction of tumors near the hip joint]. / Komplikationsmanagement nach Resektion und Defektrekonstruktion hüftgelenknaher Tumoren.

BACKGROUND: Tumorous destruction of the periacetabular region and the proximal femur are a consequence of either primary malignant bone tumor manifestation or metastatic disease, which is observed much more frequently and occurs typically in these skeletal segments. Pathological fractures of the proximal femur and periacetabular regions of the pelvis have a high incidence and ultimately lead to severe pain and immobilization. TREATMENT METHODS: Advanced resection techniques and different types of defect reconstruction, allowing for oncologically sufficient resection of extensive tumors have contributed to a marked increase in the limb salvage rate. However, these procedures are associated with an increasing rate of several, sometimes severe intraoperative and postoperative complications. COMPLICATIONS: Compared to elective total hip arthroplasty, the rate of postoperative deep infections, dislocations, the incidence of pathological and periprosthetic fractures and the prevalence of deep vein thrombosis are increased with high rates of postoperative mortality and local tumor recurrence, being the most serious complications. Pelvic involvement and subsequent periacetabular resection have the highest complication rate when compared to proximal femur resection with endoprosthetic treatment. CONCLUSION: In order to minimize the risk of these intraoperative and postoperative complications wide resection and advanced reconstruction as well as complicated palliative stabilization due to malignant bone tumor growth around the hip joint should be performed in musculoskeletal tumor centers with profound expertise in osteosynthetic and endoprosthetic reconstruction of the pelvis and the proximal femur. Only in specialized centers an effective, multidisciplinary emergency management of these complications and, more importantly, reliable prevention of complications can be ensured.

Surgical management and outcome of skeletal metastatic disease of the humerus.

PURPOSE OF THE STUDY Evaluation of outcome after surgical treatment of humerus metastases with a focus on tumour and patient derived factors, timing and strategy of intervention, surgical outcome and complications. MATERIAL AND METHODS Sixty-fie patients with a mean age of 64.3 years (range 25-89) with 66 metastases of the humerus were surgically treated in a 7-year time-period and retrospectively reviewed. RESULTS Renal cell carcinoma and breast cancer were the most abundant types of primary tumour. The mean time from diagnosis of primary tumour to fist metastasis was 14.5 months (range 0-173). The mean time from diagnosis of metastasis to surgery was 21.4 months (range 0-173). 38/28 intramedullary nails/locking plates were used for 58/8 manifest/impending pathological fractures. Mean cumulative survival was 16.3 months and implant failure rate was 6.1% with a mean time from initial surgery to revision of 22.2-20.6 months. CONCLUSIONS Our data indicate that treatment with intramedullary fiation or cement augmented plate osteosynthesis is successful for the vast majority of patients, but thorough clinical evaluation and precise decision making adapted to the patient's estimated life expectancy must be applied to avoid overtreatment or risk of implant failure. Key words: bone metastases, skeletal metastatic disease, humerus metastasis, pathologic fracture, impending fracture.

[Flap coverage of soft tissue defects after total knee arthroplasty]. / Lappenplastiken bei Weichteildefekten nach endoprothetischem Kniegelenkersatz.

Due to the marginal periarticular soft tissue envelope and the high risk of concomitant soft tissue or periprosthetic infection with the presence of exposed metal or bone, soft tissue defects after total knee arthroplasty are always a relevant surgical problem. Specific patient-related, intra- and postoperative risk factors have been identified and need to be considered during the course of treatment. Often a profound management of underlying infection must accompany the staged defect treatment which could require a prosthesis explantation with secondary revision in the case of a deep infection and involvement of the prosthesis. Four stages of soft tissue defects have been introduced (types A-D) and criteria for differentiation are the overall soft tissue coverage, the exposure, respectively, necrosis of the extensor mechanism, preservation or involvement of the joint capsule and/or an accompanying septic loosening of the prosthesis. The concept of plastic coverage follows a stage-adapted algorithm and includes secondary wound healing and mesh coverage for superficial defects, fasciocutaneous flaps for moderate defects and pedicled or free muscle flaps for deep defect situations with extension into the joint capsule. Crucial factors for a successful therapy include the early identification and precise analysis of defect characteristics, the careful preparation of the wound bed with serial debridements and the diligent flap coverage with early consultation of plastic-surgical expertise.

Radiofrequency ablation of osteoid osteomas: analgesia and patient satisfaction in long-term follow-up.

PURPOSE: To review the long term clinical outcomes in the treatment of osteoid osteoma (OO) using radiofrequency ablation (RFA). MATERIALS AND METHODS: Our retrospective study included 59 patients who were treated in the period from April 2001 to December 2012 due to a symptomatic OO using RFA. Here, the occurrence of complications and postoperative recurrence, as well as postoperative patient satisfaction were examined. Patients satisfaction was assessed by means of a telephone interview with the visual analogue scale (VAS). RESULTS: Mean follow-up was 50 months (2 - 116 months). The average size of the nidus was 6 mm (range 2 - 14 mm). After initial radiofrequency ablation 11.8 % (7/59) of patient showed a recurrence of symptoms. Symptoms could successfully be treated by a second ablation in 5 patients. Assisted success rate was therefore 96.6 % (57/59). The complication rate was 5.1 % (2 major and one minor complication). Furthermore we report a very high patient satisfaction and acceptance of therapy. CONCLUSION: RFA is a very successful therapy of symptomatic OOs with a high patient satisfaction. KEY POINTS: ▶ Osteoid osteomas (OO) are rare benign bone tumors of the childhood and adolescence. ▶ Treatment of OOs with minimal-invasive radiofrequency ablation (RFA) shows a high patient satisfaction. ▶ RFA is by now the standard therapy of symptomatic OOs.

[Solitary spinal metastases. Is aggressive surgical management justified?]. / Solitäre Metastasen der Wirbelsäule. Indikationen für eine aggressive chirurgische Therapie?

Advances in oncological and surgical therapies have led to a significant increase in life expectancy of cancer patients and also prolonged survival of patients with isolated or multiple metastases. Among the skeletal manifestations the spine is the most often affected site. Using novel imaging techniques with higher resolution and use of metabolic signatures, the screening of cancer patients has improved considerably. Consequently, the diagnosis of metastases is becoming increasingly more sensitive. Therefore, but also due to more effective polychemotherapy protocols, singular or solitary metastases are more frequently observed either in the early stages or as a result of a controlled malignant tumor entity (stable disease). The questions whether a solitary metastasis really exists (illusion or reality?) and its radical oncological and surgical treatment as a circumscribed singular tumor manifestation, is really relevant for the overall prognosis, remains controversial. However, it seems evident that a biologically favorable underlying tumor biology, radical treatment of the primary tumor and a long metastasis-free interval are valid predictors of a good oncological outcome. In the presence of a solitary metastasis under these circumstances (typical example: solitary metastasis of renal cell carcinoma many years after radical tumor nephrectomy) a radical surgical procedure (en bloc spondylectomy) can significantly improve the long-term prognosis of this patient group in combination with adjuvant chemotherapy and/or radiotherapy. However, a thorough evaluation of the overall survival prognosis, a detailed and complete staging followed by a treatment consensus in the interdisciplinary tumor board has to precede any therapeutical decisions.

[Manifestation of osteosarcoma of chronic osteomyelitis: 2 case reports]. / Osteosarkommanifestation bei chronischer Osteomyelitis: 2 Fallberichte.

The treatment and outcome of two patients suffering from osteosarcoma of the lower extremity evolving many years after manifestation of chronic osteomyelitis are reported. After neoadjuvant polychemotherapy in one patient en bloc resection, interposition of a cement spacer and stabilization was performed in both cases. After eradication of infections final segmental reconstruction was accomplished by knee arthrodesis using rotation plasty of the split femoral condyle, free local fibula transposition and gastrocnemius muscle transfer. A custom-made diaphyseal replacement (3D-rapid prototyping titanium mesh) was used for defect reconstruction. After 1 year postoperative follow-up and restaging both patients showed no evidence of recurrent disease and had no local or systemic signs of infection.

Radiofrequency ablation of osteoid osteomas: analgesia and patient satisfaction in long-term follow-up.

PURPOSE: To review the long term clinical outcomes in the treatment of osteoid osteoma (OO) using radiofrequency ablation (RFA). MATERIALS AND METHODS: Our retrospective study included 59 patients who were treated in the period from April 2001 to December 2012 due to a symptomatic OO using RFA. Here, the occurrence of complications and postoperative recurrence, as well as postoperative patient satisfaction were examined. Patients satisfaction was assessed by means of a telephone interview with the visual analogue scale (VAS). RESULTS: Mean follow-up was 50 months (2 ­116 months). The average size of the nidus was 6mm (range 2 ­ 14 mm). After initial radiofrequency ablation 11.8 % (7/59) of patient showed a recurrence of symptoms. Symptoms could successfully be treated by a second ablation in 5 patients. Assisted success rate was therefore 96.6 % (57/59). The complication rate was 5.1 % (2 major and one minor complication). Furthermore we report a very high patient satisfaction and acceptance of therapy. CONCLUSION: RFA is a very successful therapy of symptomatic OOs with a high patient satisfaction. KEY POINTS: Osteoid osteomas (OO) are rare benign bone tumors of the childhood and adolescence. Treatment of OOs with minimal-invasive radiofrequency ablation (RFA) shows a high patient satisfaction. RFA is by now the standard therapy of symptomatic OOs.

[Biomechanical aspects of complex reconstructions following radical resection of thoracolumbar spinal tumors]. / Biomechanische Aspekte radikaler Resektionen und deren Rekonstruktion an der thorakolumbalen Wirbelsäule.

The total number of spinal tumors has increased over the past decade. However, the average survival time of tumor patients has increased due to improvements in the multidisciplinary treatment regimes. Therefore, radical tumor resection and complex reconstruction were developed in spinal surgery. Various reconstructive options for the throracolumbar spine are nowadays available and are depicted in this article. The success of complex reconstructive surgery relies on biomechanical principles and reconstruction is dependent on the size and location of the lesion, bone porosity and implant systems used. Special emphasis of this article focuses on en bloc vertebrectomy which is the most radical approach of spinal tumor surgery. The biomechanical aspects of different types of lesions and the reconstructive options are discussed in the context of the currently published literature.

[Surgical management of thoracolumbar spinal sarcoma]. / Chirurgisches Management von Sarkomen der thorakolumbalen Wirbelsäule.

Primary malignant tumors of the thoracolumbar spine are very rare. The most common entities are chordoma, followed by osteosarcoma, Ewing's sarcoma and chondrosarcoma. Detailed imaging and a sequential biopsy are the most important diagnostic steps. The surgical staging system of Weinstein and Boriani permits a precise analysis of tumor expansion. Therapy under a multimodal concept consists of (neo-) adjuvant therapy and possible radiation. The surgical therapy should be performed as an en bloc excision with sufficient resection borders. The reconstruction of the defects must include methods of vertebral body replacement and long posterior instrumentation. En bloc spondylectomy is a very demanding technique and demands strict indications, close cooperation with adjacent specialties and exact planning of the operation. Only in this manner is the operation possible and offers the only sufficient form of resection. The execution of the en bloc spondylectomy should be left to spine centers with great experience, as they could also guarantee the respective complication management.

[Multisegmental en bloc spondylectomy. Indications, staging and surgical technique]. / Multisegmentale En-bloc-Spondylektomie. Indikation, Staging und chirurgische Technik.

OBJECTIVE: Description of the surgical technique including approaches and spinal reconstruction principles for patients scheduled for multilevel en bloc excision of vertebral tumors (multisegmental total en bloc spondylectomy) with the aim to attain tumor-free margins and minimize the risk of local and systemic tumor recurrence. Restoration of biomechanically sufficient spinal stability. Functional preservation and/or regaining of adequate neurological function. INDICATIONS: Primary malignant and benign, aggressive spinal tumors. Solitary metastatic tumors of biologically and prognostically favorable primary tumor (good prognostic scores). Extracompartmental, multisegmental vertebral tumor manifestations according to Tomita type 6. CONTRAINDICATIONS: Diffuse spinal/vertebral tumor spread according to Tomita type 7 (disseminated spinal metastatic disease). Detection of distant metastases in the staging investigation. Biologically unfavorable tumor entities or primary systemic malignant tumors/diffuse disseminated malignoma (Tomita score < 4-5 points, Tokuhashi score < 12 points). SURGICAL TECHNIQUE: Depending on tumor growth, sequential performance of the anterior and posterior approach for local tumor release and preparation/replacement of encased large vessels. Posterior approach via dorsomedial incision and exposure of the posterior vertebral elements. Costotransversectomy, resection of the facets, resection of paravertebral rib segments. Laminectomy in the tumor-free lamina segment, resection of the ligamentum flavum and paradural ligation of affected nerve roots, bilateral ligation of the segmental arteries. Digital extrapleural palpation and dissection to the anterior vertebral body parts. Insertion of S-shaped spatulas ventral to the anterior aspect of the spine, and dissection of the disc spaces and the posterior longitudinal ligament. Instrumentation of pedicle screws and unilateral rod fixation, mobilization and careful, manual turning out/rotation of the affected vertebral segments around the longitudinal axis of the spinal cord. Interpositioning of a carbon-composite cage from posterior filled with autologous bone. Completion of the posterior stabilization, soft tissue closure, Goretex patch fixation if required in cases of chest wall resections. POSTOPERATIVE MANAGEMENT: Intensive care monitoring with balanced volume replacement/transfusion. Postoperative adjuvant radiotherapy or chemotherapy, depending on the protocol and resection margins.

Surgical management of recurrent thoracolumbar spinal sarcoma with 4-level total en bloc spondylectomy: description of technique and report of two cases.

INTRODUCTION: The descriptions of total spondylectomy and further development of the technique for the treatment of vertebral sarcomas offered for the first time the opportunity to achieve oncologically sufficient resection margins, thereby improving local tumor control and overall survival. Today, single level en bloc spondylectomies are routinely performed and discussed in the literature while only few data are available for multi-level resections. However, due to the topographic vicinity of the spinal cord and large vessels, the multisegmental resections are technically demanding, represent major surgery and only few case reports are available. Surgical options are even more limited in cases of revision surgery and local recurrences when en bloc spondylectomy was considered to be not feasible due to high risk of vital complications in expanding resection margins. Deranged anatomy, implants in situ and extensive intra-/paraspinal scar tissue formation resulting from previously performed approaches and/or radiation are considered the principal complicating factors that usually hold back spine surgeons to perform revision for resection leaving the patient to palliative treatment. METHODS: We present two patient cases with previously performed piecemeal vertebrectomy in the thoracic spine due to a solitary high-grade spinal sarcoma. After extensive re-staging, both patients underwent a multi (4)-level en bloc spondylectomy in our department (one patient with combined en bloc lung resection). Except a local wound disturbance, there was no severe intra- or postoperative complication. RESULTS: After multilevel en bloc spondylectomy both patients showed a good functional outcome without neurological deficits, except those resulting from oncologically scheduled resection of thoracic nerve roots. After a median follow-up of 13 months, there was no local recurrence or distant metastasis. The reconstruction using a posterior screw rod system that is interconnected to an anterior vertebral body replacement with a carbon composite cage showed no implant failure or loosening. In summary, the approach of a multilevel en bloc surgery for revision and oncologically sufficient resection in cases of spinal sarcoma recurrences seems possible. However, interdisciplinary decision making in a tumor board, realistic evaluation of surgical resectability to attain tumor free margins, advanced experiences in spinal reconstructions and involvement of vascular, visceral and thoracic surgical expertise are essential preconditions for acceptable oncological and functional outcome.

Minimally invasive combined anterior kyphoplasty for osteolytic C2 and C5 metastases.

Kypho- and vertebroplasty are widely accepted for treating patients suffering from pathologic thoracolumbar lesions, in particular diffuse metastatic-induced fractures. They provide rapid pain relief and the restoration of spinal stability. In the cervical spine, attempts have been made to use cement augmentation for these indications. However, the cervical spine's anatomy complicates the transpedicular approach, as well as the pre-formation of a vertebral body cavity and the application of bone cement. We report the case of a 46-year-old woman suffering from symptomatic C2 and C5 osteolysis caused by metastatic breast cancer. Following a surgical staging and classification (Tokuhashi-Score) that indicated palliative procedures, we performed a C2 and C5 kyphoplasty using one minimal-invasive anterior approach through a small incision. We observed an uneventful procedure and postoperative course as well as immediate pain relief and patient mobilization. Last patient follow-up at 3 months showed an excellent outcome. Our observations showed cervical spine kyphoplasty via a minimally invasive anterior approach to be feasible, successful and safe surgical method in the interdisciplinary palliative treatment.

Limb-salvage reconstruction with MUTARS hemipelvic endoprosthesis: a prospective multicenter study.

BACKGROUND: Limb-sparing surgery with hemipelvic megaprosthetic replacement is often limited by the high rate of associated complications. The aim of this evaluation was to assess clinical and oncological findings with respect to type, treatment and outcome of post-operative complications. METHODS: First results of 40 patients treated with individual MUTARS hemipelvic endoprostheses were evaluated in a prospective multicenter study. RESULTS: The mean follow-up period of the 27 male and 13 female patients was 24 months (range 1-61). The diagnosis was, in 29 cases, a primary bone or soft tissue sarcoma, in 11 patients, a metastasis. Clinical evaluation showed a mean Enneking score of 50% (range 10-70%). The oncological outcome revealed 25 patients (62.5%) alive with no evidence of disease. Seventeen of them had a primary tumour, eight a metastatic malignancy. Seven patients (17.5%) had died of their disease and eight (20%) were still alive but had developed a metastases and/or had had a recurrence of the primary tumour. The one- and two-year overall survival rate of the patients was 89% (+/- 0.10) and 81% (+/- 0.19), respectively. Post-operative complications occurred in 75% of the patients, predominantly wound-related disorders. The rate of implant revision was 22.5% with three septic and six aseptic cases of implant loosening. The estimated three-year-survival rate of the implant was 61.4% [CI95%: 0.36;0.87]. CONCLUSIONS: Periacetabular endoprosthetic replacement showed an acceptable functional and oncological outcome but had a high complication rate owing, predominantly, to infection. The indication for hemipelvic prosthesis in patients with a metastatic disease must be considered seriously.

Bone sarcoma of the spine.

Primary malignant bone tumors of the vertebral column, i.e., bone sarcomas of the spine, are inherently rare entities. Vertebral osteosarcomas and chordomas represent the largest groups, followed by the incidence of chondro-, fibro-, and Ewing's sarcomas. Detailed clinical and neurological examination, complete radiographic imaging [radiographs, computed tomography (CT), magnetic resonance imaging (MRI)], and biopsy are the decisive diagnostic steps. Oncosurgical staging for spinal tumors can serve as a decision-guidance system for an individual's oncological and surgical treatment. Subsequent treatment decisions are part of an integrated, multimodal oncological concept. Surgical options comprise minimally invasive surgery, palliative stabilization procedures, and curative, wide excisions with complex reconstructions to attain wide or at least marginal resections. The most aggressive mode of surgical resection for primary vertebral column tumors is the total en bloc vertebrectomy, i.e., single- or multilevel en bloc spondylectomy. En bloc spondylectomy involves a posterior or combined anterior/posterior approach, followed by en bloc laminectomy, circumferential (360 degrees) vertebral dissection, and blunt ventral release of the large vessels, intervertebral discectomy and rotation/ en bloc removal of the vertebra along its longitudinal axis. Due to the complex interdisciplinary approach and the challenging surgical resection techniques involved, management of vertebral bone sarcomas is recommended to be performed in specific musculoskeletal tumor centers.

MR-guided laser ablation of osteoid osteoma in an open high-field system (1.0 T).

Computed tomography is the standard imaging modality to minimize the extent of surgical or ablative treatment in osteoid osteomas. In the last 15 years, since a description of thermal ablation of osteoid osteomas was first published, this technique has become a treatment of choice for this tumor. We report the case of a 20-year-old man with an osteoid osteoma treated with laser ablation in an open high-field magnetic resonance imaging scanner (1.0 T). The tumor, located in the right fibula, was safely and effectively ablated under online monitoring. We describe the steps of this interventional procedure and discuss related innovative guidance and monitoring features and potential benefits compared with computed tomographic guidance.