Image guided radiofrequency thermo-ablation therapy of chondroblastomas: should it replace surgery?

Benign Bone Tumors Beyond Osteoid Osteoma: Percutaneous Minimally Invasive Image-Guided Interventions

Painful benign bone tumors often adversely influence quality of life primarily due to skeletal-related events such as unremittable pain, pathologic fracture, neurologic deficit, as well as skeletal growth disturbance. Substantial advances in percutaneous minimally invasive interventions for treatment of painful benign bone tumors beyond osteoid osteoma have been established as safe, efficacious, and durable treatments to achieve definitive cure. This article details the available armamentarium and most recent advances in minimally invasive percutaneous interventions and the role of radiologists for the management of patients with benign bone tumors beyond osteoid osteoma.

Use of a Cannulated, Percutaneous Expandable Reamer for Physeal Sparing Excision of a Femoral Head Chondroblastoma

The treatment of chondroblastoma in the epiphysis of the femoral head in skeletally immature individuals is challenging and often requires surgical hip dislocation. We present a unique method of percutaneous use of an expandable reamer (X-REAM, Wright Medical) to treat a chondroblastoma of the femoral head in a 9-year-old boy without requiring surgical hip dislocation. The described technique provides access to the tumor in the proximal femoral epiphysis and local tumor control. However, the approach involves placing a cannula through the epiphyseal plate, resulting in partial premature epiphyseal closure. At 5 years after surgery, the patient has an asymptomatic leg-length discrepancy and radiographic evidence of premature physeal closure, but no restrictions on activity or evidence of local recurrence. A percutaneous expandable reamer can be used to treat chondroblastoma of the femoral head while avoiding surgical hip dislocation.

Benign Bone Tumors: State of the Art in Minimally Invasive Percutaneous Interventions

Painful benign bone tumors most commonly affect pediatric patients and young adults. They may be associated with skeletal-related events such as intractable pain, pathologic fracture, neurologic deficit as a consequence of nerve or spinal cord compression, as well as growth disturbance. Consequently, they often result in diminished activity and adversely affect quality of life. There have been substantial recent advances in percutaneous minimally invasive image-guided interventions for treatment of painful benign bone tumors including thermal ablation (radiofrequency ablation, cryoablation, microwave ablation, laser photocoagulation, and high-intensity focused US ablation), chemical (alcohol) ablation, cementoplasty, and intralesional injections. The safety, efficacy, and durability of such interventions have been established in the recent literature and as such, the role of musculoskeletal interventional radiologists in the care of patients with benign bone lesions has substantially expanded. The treatment goal of minimally invasive musculoskeletal interventions in patients with benign bone tumors is to achieve definitive cure. The authors detail the most recent advances and available armamentarium in minimally invasive image-guided percutaneous interventions with curative intent for the management of benign bone tumors. ^© RSNA, 2022.

Chondroblastoma Affecting the Apophysis of the Greater Trochanter in a Child

Chondroblastomas are rare primary bone tumours typically affecting the epiphyses and less frequently the apophyses of the growing skeleton. Most cases are treated by intralesional curettage with or without local adjuvants and this technique can produce good long-term outcomes. Herein, we describe a case of chondroblastoma of the greater trochanter in a 12-year-old male child that was treated by intralesional curettage and grafting with calcium phosphate bone cement (Neocement Inject® P, Bioceramed, Loures, Portugal). A brief review of the literature is also presented.

Radio Frequency Ablation for the Treatment of Appendicular Skeleton Chondroblastoma: Is It an Excellent Alternative? Systematic Review and Meta-Analysis

Radio frequency ablation (RFA) is a minimally invasive technique that has become recognized in clinical practice for treating chondroblastoma, although curettage with bone graft is the standard treatment. Chondroblastoma is a locally aggressive cartilaginous bone tumor, representing nearly 5% of benign bone tumors. Chondroblastoma shows a preference toward the epiphysis or apophysis of long bones, but it was also reported in vertebrae and flat bones. The management of chondroblastoma could be challenging due to the risk to injure the epiphyseal plate or difficult location. The aim of this study was to determine if RFA is a suitable alternative to curettage with bone graft for the treatment of chondroblastoma. Moreover, there will be an evaluation of RFA's effectiveness in terms of symptoms relief; we also define the proper size of the lesion to be treated with RFA, and discuss the complications after the procedure, including the recurrence rate. Furthermore, we review the best imaging method to evaluate the therapeutic response of RFA and for the detection of residual disease early after the ablation. A comprehensive PubMed and Google Scholar search followed the Preferred Reporting Items for Systematic Review and Meta-Analysis 2020 checklist guidelines. Ninety-seven patients were identified after reviewing the available full texts of nine articles. The results of the current review provide further evidence to support the use of RFA as an alternative option to surgery.

Direct femoral head approach without surgical dislocation for femoral head chondroblastoma: a report of two cases

BACKGROUND

Chondroblastomas are rare, benign, locally aggressive lesions that appear in the epiphysis. Surgery for femoral head chondroblastoma (FHCB) is difficult. Conventional treatment with curettage via a drilled tunnel along the femoral neck can damage the growth plate and is associated with high local recurrence rates. The trapdoor procedure, which directly facilitates lesion access from the femoral head articular surface, can reduce local recurrence and avoid growth plate damage, although it requires surgical dislocation. Little is known about the long-term results of this direct articular surface approach, and there are no case reports on trapdoor procedures without dislocation.

CASE PRESENTATION

We report two cases (patients aged 12 and 15 years) of FHCB presented with coxalgia treated using the trapdoor procedure without surgical dislocation. Both surgeries were performed with patients in the semi-lateral position. The hip joint was exposed via an anterior approach, and a capsulotomy was performed at the superior rim of the acetabulum, followed by the external rotation of the hip joint. With a fine osteotome, a rectangular flap (trapdoor) was opened on the cartilage surface in the lateral non-weight-bearing area, and curettage of the lesion followed by bone and/or bone substitute grafting was performed. Subsequently, the trapdoor was replaced in its original position. There has been no local recurrence or femoral head aseptic necrosis after more than 6 and 12 years for patients 1 and 2, respectively. Both patients had musculoskeletal tumor society scores of 100% at follow-up and are enjoying a normal active life.

CONCLUSIONS

This direct femoral head approach without dislocation may be a simple treatment alternative for FHCB.

Computer 3D modeling of radiofrequency ablation of atypical cartilaginous tumours in long bones using finite element methods and real patient anatomy

BACKGROUND

Radiofrequency ablation (RFA) is a minimally invasive technique used for the treatment of neoplasms, with a growing interest in the treatment of bone tumours. However, the lack of data concerning the size of the resulting ablation zones in RFA of bone tumours makes prospective planning challenging, needed for safe and effective treatment.

METHODS

Using retrospective computed tomography and magnetic resonance imaging data from patients treated with RFA of atypical cartilaginous tumours (ACTs), the bone, tumours, and final position of the RFA electrode were segmented from the medical images and used in finite element models to simulate RFA. Tissue parameters were optimised, and boundary conditions were defined to mimic the clinical scenario. The resulting ablation diameters from postoperative images were then measured and compared to the ones from the simulations, and the error between them was calculated.

RESULTS

Seven cases had all the information required to create the finite element models. The resulting median error (in all three directions) was -1 mm, with interquartile ranges from -3 to 3 mm. The three-dimensional models showed that the thermal damage concentrates close to the cortical wall in the first minutes and then becomes more evenly distributed.

CONCLUSIONS

Computer simulations can predict the ablation diameters with acceptable accuracy and may thus be utilised for patient planning. This could allow interventional radiologists to accurately define the time, electrode length, and position required to treat ACTs with RFA and make adjustments as needed to guarantee total tumour destruction while sparing as much healthy tissue as possible.

Surgical hip dislocation for treatment of femoral head chondroblastoma: efficacy and safety

PURPOSE

Femoral head chondroblastoma poses a surgical challenge. Anatomical limitations may lead to increased risk of local recurrence, damage to the articular cartilage, growth disturbances, and/or avascular necrosis (AVN). We are presenting our results with surgical hip dislocation approach with the aim to evaluate its efficacy in preventing recurrence and its safety, preserving a functional hip joint and avoiding complications.

PATIENTS AND METHODS

Ten patients were managed using surgical hip dislocation with direct access to femoral head lesions, extended curettage through a modified trapdoor approach, and cement reconstruction. These were six males and four females, with a mean age of 17 ± 2.7 years (range: 14-20) and a mean follow-up of 34 ± 12 months (range: 17-57). The lesion extended into the neck in 60% of patients with the physis being either closed in seven or closing in three patients.

RESULTS

We had a single case (10%) of recurrence at the trochanters for which re-curettage was done. However, all patients had their hips preserved with good function at the latest follow-up, and no serious complications recorded. The Musculoskeletal Tumor Society score improved significantly from a pre-operative median of 23.5 (range: 16-28) to a post-operative median of 29 (range: 26-30) (P = 0.005).

CONCLUSION

This report describes a safe reproducible approach to effectively manage these locally aggressive lesions with good short-term results. This is done while maintaining the integrity of the articular surface, growth plate, as well as preserving the femoral head blood supply.

Chondroblastoma treatment by radiofrequency thermal ablation: Initial experience and implementation

PURPOSE

To present our experience on the implementation of radiofrequency thermal ablation (RFA) for the treatment of chondroblastoma.

MATERIALS AND METHODS

This case series includes 12 patients (10 males) with chondroblastoma using RFA under CT guidance. Tumours were located in the humeral head (3), femoral head (2), distal femoral epiphysis (4), tibial epiphysis (2) and calcaneus (1). Tumour size ranged from 12 to 60 mm (median: 33 mm). According to tumour size and location, monopolar electrode's active tip ranged from 1 to 3 cm. Dry and perfused ablation mode was used to treat smaller (6) and larger (6) lesions, respectively. Cementation was also made in 5 cases. Technical success was considered if the tumour was treated according to the protocol and complete ablation was achieved. Clinical success was assessed according to a visual analogue scale.

RESULTS

Technical success was achieved in 11 of 13 cases (83%) afters the first treatment. After a second treatment in the 2 failed cases, pain control was achieved in all cases eventually (100% of clinical success). Follow-up MRI demonstrated resolution of oedema in all cases, as well as a necrotic area extending beyond the outer edge of the lesion in all cases except one. Radiography or CT showed stability of the lesions, with increased sclerosis and no cortex collapse. In one case, a 4 cm shortening of the humerus was observed at the end of skeletal development (7 years after treatment). In another case, early hip osteoarthritis was developed (15 years after treatment). No other long-term complications were observed.

CONCLUSION

Successful treatment of chondroblastoma can be achieved by RFA. Cementoplasty adds strength to the ablated bone in weight bearing areas. MRI hallmarks associated with clinical success were resolution of bone marrow edema, and area of necrosis extending beyond the tumour edge. Radiography and CT proved to be useful in demonstrating cortex integrity.

Percutaneous cryoablation of chondroblastoma and osteoblastoma in pediatric patients

BACKGROUND

To review the safety and efficacy of percutaneous cryoablation for the treatment of chondroblastoma and osteoblastoma in the pediatric and adolescent population.

MATERIALS AND METHODS

A retrospective review from 2016 to 2020 was performed to evaluate clinical and imaging response to percutaneous cryoablation in 11 symptomatic patients with diagnosis of chondroblastoma and osteoblastoma treated from two pediatric hospitals with at least 12-month follow-up. Technical success (correct needle placement and potential full coverage of the tumor with the planned ablation zone) and clinical success (relief of the symptoms) were evaluated. The primary objective was to alleviate pain related to the lesion(s). Immediate and late complications were recorded. Patients were followed in clinic and with imaging studies such as MRI or CT for a minimum of 6 months.

RESULTS

A total of 11 patients were included (mean 14 years, age range 9-17; male n = 8). Diagnoses were osteoblastoma (n = 4) and chondroblastoma (n = 7). Locations were proximal humerus (n = 1), femur condyle (n = 1), and proximal femur (n = 1) tibia (n = 3), acetabulum (n = 3), thoracic vertebra (n = 1) and lumbar vertebra (n = 1). Cryoablation was technically successful in all patients. Clinical success (cessation of pain) was achieved in all patients. No signs of recurrence were observed on imaging follow-up in any of the patients. One of the patients developed periprocedural right L2-L3 transient radiculopathy as major immediate complication.

CONCLUSIONS

Percutaneous image-guided cryoablation can be considered potentially safe and effective treatment for chondroblastoma and osteoblastoma in children and adolescents.

Surgical treatment of benign osteolytic lesions in the femoral head and neck: a systematic review

Background and objectives

Treatment of benign osteolytic lesions in the femoral head and neck can be extremely challenging, particularly in children with open physis or for aggressive tumors with pathological fracture. There remains the difficult management decision as to whether to perform complete excision of the involved area or only curettage. Moreover, there is no agreed consensus on the optimal approach to lesion access when performing curettage, which included the transcervical, open and direct approach. The current systematic review aims to provide guidance for selection of surgical methods in clinical practice by comparing the advantages and drawbacks of different procedures.

Methods

A comprehensive literature search of PubMed, Embase and Web of Science databases were executed for human studies restricted to the English language. The search was filtered to include studies published from January 1980 to January 2020.

Results

A total of 33 articles including 274 patients were enrolled in the final analysis. The most common diagnosis was chondroblastoma (CBT) (104, 38.0%), followed by giant cell tumor (GCT) (56, 20.4%). There were 57 (20.8%) patients with pathological fracture. Intralesional curettage was performed in 257 (93.8%) patients with the local recurrence of 12.5% at the mean follow-up of 51.5 months. The patients who were presented with open physis or curetted via transcervical approach developed higher local recurrence in patients with CBT (P < 0.001). The local recurrence rate of GCT is 33.3% after curettage, while 8 of 9 (88.9%) patients with fracture were treated successfully with joint preservation. Two of 45 (4.4%) patients developed avascular necrosis (AVN) of femoral head after surgical hip dislocation. The reported Musculoskeletal Tumor Society (MSTS) Score was comparable among patients with different approaches to curettage.

Conclusion

The majority of benign osteolytic lesions in the femoral head and neck can be treated with intralesional curettage with acceptable local tumor control and satisfactory function. The incidence of local recurrence might be decreased dramatically for lesion access under direct visualization. The native joint maintenance could be achieved even in patients with aggressive lesions presenting pathological fracture.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04442-y.

Bone Tumours of the Talus: 18-Year Cohort of Patients With Rare Osteoid Lesions

Background Bone tumours of the talus are a rare cause of ankle pain. This study aims to provide additional clinical clarity regarding the presentation and management of a minimally researched topic. Methods Sixteen patients were diagnosed with bone tumour of the talus between 2002 and 2020 following referral for ankle pain. Symptoms, diagnosis, and management were retrospectively reviewed. Patients were actively followed up until consistently symptom-free and consenting to discharge (mean of 2.9 years). An open appointment was offered to all patients to reattend the unit if symptoms recurred. Results The most common diagnosis was osteoid osteoma/osteoblastoma (nine patients), chondroblastoma (four patients), a giant cell tumour of bone, a chondral lesion in Ollier's disease and a rare metastatic renal cancer case. The mean age of onset was 29 years. Thirteen patients experienced ankle pain without a clear precipitating cause. Night pain was less common in osteoid osteoma/osteoblastoma than usually observed in the literature. The mean delay in diagnosis was two years, often due to an incorrect diagnosis of soft tissue injury. Plain radiographs are insufficient to identify most lesions. Ten patients underwent computed tomography (CT)-guided radiofrequency ablation and five patients had open surgical curettage. Ollier's disease was managed with orthotics. The five cases of recurrence across four patients were managed operatively. Conclusions Patients are usually young and healthy with benign disease, but talus tumours can cause significant functional impairment. Unexplained ankle pain should be extensively examined and be further investigated with magnetic resonance imaging (MRI) and CT scanning to avoid missing these rare tumours.

Chondroblastoma: Is intralesional curettage with the use of adjuvants a sufficient way of therapy?

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Chondroblastoma represents a rare pathology.

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An aggressive intralesional curettage leads to low recurrence rates.

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Hydrogen peroxide as adjuvant lowers the risk of local recurrence.

Background

Chondroblastoma is a rare benign cartilaginous bone tumor that represents 1–2% of all primary bone tumors. It is characterized by aggressive growth, possible recurrence after surgical treatment and, in rare cases, metastasis. Surgical management is the primary treatment and includes intralesional curettage with or without adjuvants. Local recurrence rates vary between less than 10% up to more than 30%.

Methods

In this retrospective study between 2009 and 2020 we analysed 38 cases of chondroblastoma with a mean follow-up of 27.9 months who underwent a surgical treatment in our institution. Epidemiological data, radiographic and histological examinations, different surgical techniques, complications and local recurrence were evaluated to comment on the question if curettage with or without adjuvants is a sufficient way of therapy.

Results

The study includes 25 male (65.8%) and 13 female (34.2%) patients with a mean age of 17.2 (11–51) years. The most common location of manifestation was the proximal epiphyseal humerus (34.2%), followed by the proximal tibia (26.3%) and the distal femur (15.8%). Joint involvement occurred in 28 patients (73.7%). In all cases intralesional curettage was performed; in 25 cases (65.8%) the resulting cavity was filled with bone substitute, in 7.9% (3 cases) with bone cement and in 10.5% (4 cases) with autogenous bone graft. Adjuvant hydrogen peroxide was used in 64.9% of the cases. The overall recurrence rate was 39.5% (15 cases). The following subgroup analysis showed a recurrence rate of 100% (4/4 cases) after curettage and defect reconstruction with autogenous bone. In the case of intralesional curettage and filling of the cavity with bone substitute but without use of adjuvant the recurrence rate was 50% (4/8 cases). A low recurrence rate of 11.8% (2 cases) was observed in the case of intralesional curettage, using hydrogen peroxide as adjuvant (17 cases) and bone substitute for defect reconstruction.

Conclusions

Chondroblastoma represents a rare pathology. Therapeutically an aggressive intralesional curettage with use of hydrogen peroxide as adjuvant and filling up the defect with bone substitute leads to low recurrence rates.

Surgical treatment of chondroblastoma using extended intralesional curettage with phenol as a local adjuvant

PURPOSE

The aim of this study is to report the clinical and radiological outcomes following surgical treatment of chondroblastoma by means of an extended intralesional curettage using high-speed burr, with phenol as a local adjuvant which is followed by the implantation of synthetic bone graft, aiming to lower the recurrence rate of this tumor.

PATIENTS AND METHODS

This retrospective study included 20 patients with chondroblastoma lesions during the period between 2000 and 2015.

RESULTS

Fifteen males and five females were followed up for a mean of 63.35 (26-144) months with average age at the time of presentation was 20.8 (range: 12-32) years. Nineteen patients (95%) were complaining of pain at the time of presentation, and the lesion was discovered accidently in one patient. The mean operative time was 138.5 min (75-250). At the most recent follow-up, all patients had regained full physical function without pain at the operation site.

CONCLUSION

The aggressive treatment of chondroblastoma by an extended intralesional curettage using high-speed burr with phenol as a local adjuvant seems effective in lowering the incidence of local recurrence and secondary more aggressive surgeries. Implantation of the bone defects that result from curettage with the synthetic bone substitutes is a good alternative due to rapid restoration of the mechanical strength with good remodeling.

Radiofrequency ablation of atypical cartilaginous tumors in long bones: a retrospective study

Purpose: To determine the size of the ablation zone after radiofrequency ablation (RFA) of atypical cartilaginous bone tumors (ACT) using temperature-controlled 20 and 30 mm RFA straight non-cooled electrodes.Materials and methods: Sixteen patients with ACT in their long bones, who had undergone a single-session single-application CT-guided temperature-controlled RFA, were included retrospectively in the study. Tumors with a diameter of 10-25 mm were treated with 20 mm electrodes (n = 10), and tumors of 25-35 mm, with 30 mm electrodes (n = 6). The ablated zone was measured after three months on MRI images.Results: All the tumors were within the ablated zone on the 3-month follow-up MRI scan. The mean ablation time with the electrode, at a target temperature of 90 °C, was 7.6 minutes (range 6-10). The median of the largest ablation diameters, on applying the 20 and 30 mm electrodes, were 42 mm (IQR 8.5, range 30-51 mm) and 44.5 mm (IQR 4.5, range 42-63 mm), respectively.Conclusions: All the retrospectively viewed tumors in the long bones of ACT patients treated with RFA were completely ablated. The ablation zone diameters in the bones were larger than expected, when compared to other tissues, such as the liver.

Navigation-assisted surgery for chondroblastoma arising in the femoral head: A case report

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We reported the first case to use navigation for the femoral head chondroblastoma.

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Visualization of tumor on navigation helps to minimize unnecessary destruction.

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Navigation assistance is an optimal surgical option for chondroblastoma in the femoral head.

Introduction

Surgery for chondroblastoma in the femoral head is challenging due to its inaccessibility, with high risk of local recurrence and poor functional outcomes reported. We herein report the first case of chondroblastoma in the femoral head treated by navigation-assisted surgery.

Presentation of case

A 12-year-old girl presented with persistent left hip pain and limited hip range of motion. Imaging studies revealed a well-defined osteolytic lesion in the left femoral head accompanied by extensive intra-osseous oedematous change. The bone lesion was radiologically diagnosed as chondroblastoma. With navigation assistance, curettage was performed via the anterior approach. The tumor was fully accessible from the femoral neck. After curettage, the bony defect was filled with bone substitute. The pathological diagnosis was chondroblastoma. The post-operative course was uneventful. Thirty months postoperatively, the patient was free of pain with full hip range of motion, and MR images showed no evidence of recurrence or osteonecrosis.

Discussion

This case is the first to use a navigation system for the treatment of chondroblastoma in the femoral head. The navigation system can minimize damage to intact structures and increase the efficiency of curettage by visualizing access to the tumor.

Conclusion

Navigation assistance is an optimal surgical option for chondroblastoma in the femoral head.

Clinical outcomes of chondroblastoma treated using synthetic bone substitute: risk factors for developing radiographic joint degeneration

Background

Chondroblastoma (CB) is a rare locally aggressive bone tumor that commonly occurs in the epiphysis or apophysis of long bones. Although surgical treatment of CB carries potential risk for physeal or articular cartilage damage, risk factors for joint degeneration have not been well described. In addition, we have mainly used synthetic bone substitute (SBS) to fill the bone defect after intralesional curettage as treatment for CB. This study thus aimed to evaluate the incidence of and risk factors for adjacent-joint radiographic degeneration after SBS treatment for CB.

Methods

We retrospectively reviewed 48 patients treated for CB at our institutions between 1996 and 2017. Clinical data, radiographic images, treatments, and local recurrence were analyzed.

Results

We identified 40 patients [29 males and 11 females with a mean age of 19 years (range, 8–35 years)] who received SBS to fill the defect after curettage with a minimum follow-up of 1 year. The mean follow-up period was 71 months (range, 13–239 months). A total of 8 patients (20%) developed local recurrence. Radiographic analysis showed that 5 patients (16.7%) developed radiographic joint degeneration. Joint degeneration was significantly associated with the affected joint (p = 0.004).

Conclusions

Curettage and SBS filling had been found to be a reasonable treatment method for CB, which commonly occurs in the epiphysis or apophysis. Radiographic joint degeneration was not uncommon after CB treatment, especially in the talus and proximal humerus.

Chondroblastoma in pelvis and extremities- a signle centre study of 177 cases

Introduction

Chondroblastoma is a rare benign bone tumour that usually occurs in children and young adults. They are cartilaginous tumours arising in the epiphysis or apophysis of a long bone. The tumour is classified as benign, although rare cases of pulmonary metastases have been reported. The aims of this study were to describe clinical, radiographic characteristics of chondroblastoma; to analyse the local recurrence rate and complications associated with surgery.

Material and methods

This retrospective study included 177 patients, who had been diagnosed with a chondroblastoma in extremity between 1990 and 2015.

Results

The most common site was proximal tibia 20%, followed by proximal humerus 19%, proximal femur 18%, distal femur 16% and foot 15%. One patient has died of the disease and one patient is alive after being operated for lung metastases. There was local recurrence in 25/177 (14%) patients. The median time to local recurrence was 10 months (range 3–158 months). The most common site for local recurrence was proximal tibia (22.2%). The proximal femur was the location in 32/178 (18%) of the cases. 18/32 (56%) were in the greater trochanter and 14/32 (44%) in the femoral head. The mean age was lower in tumours located in femoral head when compared to the greater trochanter; 19.5 years and 13.9 years respectively (p = =0.004). Tumours located in greater trochanter were all curetted without further complications. Local recurrence was seen more often in femoral head tumours, though without statistical significance; 3/14 (21%) and none, respectively (p = =0.073).

Conclusions

Chondroblastoma is a rare benign to intermediate grade bone tumour with a potential to metastasise. Femoral head chondroblastoma is rare, presenting 4.5% of all chondroblastoma cases. Around 50% of the chondroblastoma in femoral head. occur in patients with open growth plates.

Long-term follow-up of custom cross-pin fixation of 56 tumour endoprosthesis stems: a single-institution experience

AIMS

Aseptic loosening is a major cause of failure in cemented endoprosthetic reconstructions. This paper presents the long-term outcomes of a custom-designed cross-pin fixation construct designed to minimize rotational stress and subsequent aseptic loosening in selected patients. The paper will also examine the long-term survivorship and modes of failure when using this technique.

PATIENTS AND METHODS

A review of 658 consecutive, prospectively collected cemented endoprosthetic reconstructions for oncological diagnoses at a single centre between 1980 and 2017 was performed. A total of 51 patients were identified with 56 endoprosthetic implants with cross-pin fixation, 21 of which were implanted following primary resection of tumour. Locations included distal femoral (n = 36), proximal femoral (n = 7), intercalary (n = 6), proximal humeral (n = 3), proximal tibial (n = 3), and distal humeral (n = 1).

RESULTS

The median follow-up was 132 months (interquartile range (IQR) 44 to 189). In all, 20 stems required revision: eight for infection, five for structural failure, five for aseptic loosening, and two for tumour progression. Mechanical survivorship at five, ten, and 15 years was 84%, 78%, and 78%, respectively. Mechanical failure rate varied by location, with no mechanical failures of proximal femoral constructs and distal femoral survivorship of 82%, 77%, and 77% at five, ten, and 15 years. The survivorship of primary constructs at five years was 74%, with no failure after 40 months, while the survivorship for revision constructs was 89%, 80%, and 80% at five, ten, and 15 years.

CONCLUSION

The rate of mechanical survivorship in our series is similar to those reported for other methods of reconstruction for short diaphyseal segments, such as compressive osseointegration. The mechanical failure rate differed by location, while there was no substantial difference in long-term survival between primary and revision reconstructions. Overall, custom cross-pin fixation is a viable option for endoprosthetic reconstruction of short metaphyseal segments with an acceptable rate of mechanical failure. Cite this article: Bone Joint J 2019;101-B:724-731.

Modified trapdoor procedures by surgical dislocation approach to treat chondroblastoma of the femoral head

AIMS

The aim of this study was to evaluate the efficacy of the surgical dislocation approach and modified trapdoor procedure for the treatment of chondroblastoma of the femoral head.

PATIENTS AND METHODS

A total of 17 patients (ten boys, seven girls; mean age 16.4 years (11 to 26)) diagnosed with chondroblastoma of the femoral head who underwent surgical dislocation of the hip joint, modified trapdoor procedure, curettage, and bone grafting were enrolled in this study and were followed-up for a mean of 35.9 months (12 to 76). Healing and any local recurrence were assessed via clinical and radiological tests. Functional outcome was evaluated using the Musculoskeletal Tumour Society scoring system (MSTS). Patterns of bone destruction were evaluated using the Lodwick classification. Secondary osteoarthritis was classified via radiological analysis following the Kellgren-Lawrence grading system. Steinberg classification was used to evaluate osteonecrosis of the femoral head.

RESULTS

The epiphyseal plate was open, closing, and closed in five, five, and seven patients, respectively. In total, eight, six, and three patients were classified as having Lodwick classification IA, IB, and IC, respectively. Allogeneic and autogenous bone grafting was used in 13 and four patients, respectively. All patients had good bone healing and no local recurrence was observed. One patient developed osteonecrosis of the femoral head (Steinberg IA) and one developed secondary osteoarthritis of the hip joint (Kellgren-Lawrence Grade II). The mean postoperative MSTS functional score was 27.7 (24 to 30).

CONCLUSION

Surgical dislocation and modified trapdoor procedures are safe and effective techniques for treating chondroblastoma in the femoral head. Cite this article: Bone Joint J 2019;101-B:732-738.

Percutaneous Cryotherapy for Treatment of Chondroblastoma: Early Experience

Surgical curettage is currently the standard of care for the chondroblastoma, but in peri-articular tumors it is limited by its morbidity. In this preliminary report, we evaluate the feasibility of percutaneous cryotherapy as an alternative ablative treatment for chondroblastoma. Three patients with a chondroblastoma treated by CT scan-guided cryotherapy are presented in this article. Pain permanently disappeared 2 days after the procedure. No local tumor recurrence or cartilage damage was observed by MRI performed 1 year after the intervention. This preliminary case report suggests that percutaneous cryotherapy may be a possible alternative to the current standard of care in chondroblastoma. Further studies are needed to evaluate if this technique offers similar anti-tumoral efficacy while providing better pain relief and less morbidity than curettage.

What Happens to the Articular Surface After Curettage for Epiphyseal Chondroblastoma? A Report on Functional Results, Arthritis, and Arthroplasty

BACKGROUND

Chondroblastoma is an uncommon, benign, but locally aggressive bone tumor that occurs in the apophyses or epiphyses of long bones, primarily in young patients. Although some are treated with large resections, aggressive curettage and bone grafting are more commonly performed to preserve the involved joint. Such intralesional resection may result in damage to the growth plate and articular cartilage, which can result in painful arthritis. Prior studies have focused primarily on oncologic outcomes rather than long-term joint status and functional outcomes.

QUESTIONS/PURPOSES

(1) What local complications can be expected after aggressive intralesional curettage of epiphyseal chondroblastoma? (2) What is the joint survival of a joint treated in this way for chondroblastoma? (3) What additional procedures are used in treating symptomatic joint osteoarthritis after treatment of the chondroblastoma? (4) What are the functional outcomes in this group of patients?

METHODS

A retrospective study of our prospectively collected database between 1975 and 2013 was done. We found 64 patients with a diagnosis of chondroblastoma of bone. After applying our selection criteria, 53 patients were involved in this study. We excluded seven patients with tumors initially treated with en bloc resection (five located in the extremities and two in the axial skeleton) and two patients with apophyseal tumors. One patient who underwent nonsurgical treatment and one patient lost to followup were also excluded. The mean age was 18 years (range, 11-39 years); the minimum followup was 2 years with a mean followup 77 months (range, 24-213 months). We analyzed all patients with a diagnosis of epiphyseal chondroblastoma of the limb treated with aggressive curettage and joint preservation surgery. During the period in question, our general indications for curettage were patients with active, painful tumors and those with more aggressive ones that remained intracompartmental, whereas initial wide en bloc resection was indicated in patients who had tumors with an extracompartmental extension breaching the adjacent joint cartilage and massive articular destruction. The tumor location was the distal femur in 14 patients, proximal tibia in 11, proximal humerus in 10, proximal femur in eight, the talus in seven, and elsewhere in the lower extremity in three. Local complications including joint degeneration and tumor recurrence were evaluated. Based on radiographic analysis, secondary osteoarthritis was classified by using the Kellgren-Lawrence grading system from Grade 0 to Grade IV. Patients who underwent joint replacement resulting from advanced symptomatic osteoarthritis were considered to have had joint failure for purposes of survivorship analysis, which was estimated using the Kaplan-Meier method. Functional results were evaluated with the Musculoskeletal Tumor Society functional score by the treating surgeon, who transcribed the results on the digital records every 6 months of followup.

RESULTS

Twenty-two patients (42%) developed 26 local complications. The most common local complication was osteoarthritis in 20 patients (77% [20 of 26 complications]); tumor recurrence was observed in four patients; an intraarticular fracture and superficial infection treated with surgical débridement and antibiotics developed in one patient each. Joint survival was 90% at 5 years (95% confidence interval [CI], 76%-100%) and 74% at 10 years (95% CI, 48%-100%). Proximal femoral tumor location was associated with lower survivorship of the joint than other locations showing a 5-year survival rate of 44% (95% CI, 0%-88%; p = 0.000). Of the 20 patients with osteoarthritis, four were symptomatic enough to undergo joint replacement, all of which were for tumors in the proximal femur. The mean Musculoskeletal Tumor Society functional score was 28 of 30 points (93%).

CONCLUSIONS

Osteoarthritis was a frequent complication of aggressive curettage of epiphyseal chondroblastoma, and tumors located in the proximal femur appeared to be at particular risk of secondary osteoarthritis and prosthetic replacement. Because chondroblastoma is a tumor that disproportionately affects younger patients, the patient and surgeon should be aware that arthroplasty at a young age is a potential outcome for treatment of proximal femoral chondroblastomas.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Percutaneous Image-Guided Musculoskeletal Tumor Treatments

OBJECTIVE

The purpose of this article is to review the current guidelines and recommendations for percutaneous image-guided treatment of musculoskeletal tumors.

CONCLUSION

With the ongoing technologic advances, it is essential that the musculoskeletal interventionalist is familiar with the current tools and techniques available for the treatment of soft-tissue and bone tumors. Fortunately, many of these tools are readily available in a standard interventional radiology department and can be easily applied to the musculoskeletal system.

Interventional articular and para-articular knee procedures

The knee is a common area of the body to undergo interventional procedures. This article discusses image-guided interventional issues specific to the knee area. The soft tissues in and around the knee are frequently affected by sport-related injuries and often need image-guided intervention. This article details the specific technical issues related to intervention in these soft tissues, including the iliotibial tract, fat pads, patellar tendon and other tendons, bursae and the meniscus. Most often, simple procedures such as injection and aspiration are performed without image guidance. Rarely image-guided diagnostic arthrography and therapeutic joint injections are necessary. The technique, indications and diagnostic considerations for arthrography are discussed in this article. Primary bone and soft-tissue tumours may involve the knee and adjacent soft tissues. Image-guided biopsies are frequently necessary for these lesions; this article details the technical issues related to image-guided biopsy around the knee. A number of newer ablation treatments are now available, including cryoablation, high-frequency ultrasound and microwave ablation. Radiofrequency ablation, however, still remains the most commonly employed ablation technique. The indications, technical and therapeutic considerations related to the application of this technique around the knee are discussed here. Finally, we briefly discuss some newer, but as of yet, unproven image-guided interventions for osteochondral lesions and Brodie's abscess.

Radiofrequency thermo-ablation of PVNS in the knee: initial results

INTRODUCTION

Pigmented villonodular synovitis (PVNS) is normally treated by arthroscopic or open surgical excision. We present our initial experience with radiofrequency thermo-ablation (RF ablation) of PVNS located in an inaccessible location in the knee.

MATERIALS

Review of all patients with histologically proven PVNS treated with RF ablation and with at least 2-year follow-up.

RESULTS

Three patients met inclusion criteria and were treated with RF ablation. Two of the patients were treated successfully by one ablation procedure. One of the three patients had a recurrence which was also treated successfully by repeat RF ablation. There were no complications and all patients returned to their previous occupations following RF ablation.

CONCLUSION

In this study we demonstrated the feasibility of performing RF ablation to treat PVNS in relatively inaccessible locations with curative intent. We have also discussed various post-ablation imaging appearances which can confound the assessment for residual/recurrent disease.