We treated 58 patients with osteoid osteoma by CT-guided radiofrequency ablation (RF). In 16 it followed one or two unsuccessful open procedures. It was performed under general anaesthesia in 48, and spinal anaesthesia in ten. The nidus was first located by thin-cut CT (2 to 3 mm) sections. In hard bony areas a 2 mm coaxial drill system was applied. In softer areas an 11-gauge Jamshidi needle was inserted to allow the passage of a 1 mm RF probe into the centre of the nidus. RF ablation was administered at 90°C for a period of four to five minutes. Three patients had recurrence of pain three, five and seven months after treatment, respectively, and a second percutaneous procedure was successful. Thus, the primary rate of success for all patients was 95% and the secondary rate was 100%. One minor complication was encountered. CT-guided RF ablation is a safe, simple and effective method of treatment for osteoid osteoma

We treated 106 patients with a peripheral osteoid osteoma by conventional surgical methods; 81 had curettage and 25 en-bloc resection. The rate of local recurrence after curettage was 12% and after en-bloc resection 4.5%. Postoperative fractures were observed in 3% after curettage and in 4.5% after en-bloc resection. We compared our findings with those reported in the literature after minimally invasive treatment and concluded that curettage can be regarded as the treatment of choice in patients in whom minimally invasive methods do not offer any advantage, for example, for subperiosteal tumours which are readily accessible, or when the diagnosis is unclear and further histological analysis is required

We report the results of a prospective study of 23 patients in which interstitial laser photocoagulation (ILP) was used to treat an osteoid osteoma. ILP is a technique in which tumour tissue is destroyed by direct heating using low-power laser light energy delivered by thin (400 μm) optical fibres which are introduced percutaneously into the tumour under image guidance. Pain was evaluated before operation and at the latest follow-up using a visual analogue scale with 0 denoting no pain and 10 the worst pain imaginable. The mean follow-up was for 15 months. The results showed that the mean pain score decreased from 7.5 before operation to 0.95 at the latest follow-up. Fourteen patients had no pain and eight had minor discomfort, not requiring analgesia. One patient required a second procedure because placement of the fibre had not been accurate enough and one developed recurrent symptoms eight months after treatment. All patients were satisfied with the operation because of the rapid resolution of pain, the minimally invasive nature of the procedure, and the fact that there was no postoperative restriction of activity

Osteoid osteoma is treated primarily by radiofrequency (RF) ablation. However, there is little information about the distribution of heat in bone during the procedure and its safety. We constructed a model of osteoid osteoma to assess the distribution of heat in bone and to define the margins of safety for ablation. Cavities were drilled in cadaver bovine bones and filled with a liver homogenate to simulate the tumour matrix. Temperature-sensing probes were placed in the bone in a radial fashion away from the cavities. RF ablation was performed 107 times in tumours < 10 mm in diameter (72 of which were in cortical bone, 35 in cancellous bone), and 41 times in cortical bone with models > 10 mm in diameter. Significantly higher temperatures were found in cancellous bone than in cortical bone (p <  0.05). For lesions up to 10 mm in diameter, in both bone types, the temperature varied directly with the size of the tumour (p < 0.05), and inversely with the distance from it. Tumours of > 10 mm in diameter showed a trend similar to those of smaller lesions. No temperature rise was seen beyond 12 mm from the edge of a cortical tumour of any size. Formulae were developed to predict the expected temperature in the bone during ablation. Cite this article: Bone Joint J 2014; 96-B:677–83

Atypical cartilaginous tumours are usually treated by curettage. The purpose of this study was to show that radiofrequency ablation was an effective alternative treatment.

We enrolled 20 patients (two male, 18 female, mean age 56 years (36 to 72) in a proof-of-principle study. After inclusion, biopsy and radiofrequency ablation were performed, followed three months later by curettage and adjuvant phenolisation. The primary endpoint was the proportional necrosis in the retrieved material. Secondary endpoints were correlation with the findings on gadolinium enhanced MRI, functional outcome and complications.

Our results show that 95% to 100% necrosis was obtained in 14 of the 20 patients. MRI had a 91% sensitivity and 67% specificity for detecting residual tumour after curettage. The mean functional outcome (MSTS) score six weeks after radiofrequency ablation was 27.1 (23 to 30) compared with 18.1 (12 to 25) after curettage (p < 0.001). No complications occurred after ablation, while two patients developed a pathological fracture after curettage.

We have shown that radiofrequency ablation is capable of completely eradicating cartilaginous tumour cells in selective cases. MRI has a 91% sensitivity for detecting any residual tumour. Radiofrequency ablation can be performed on an outpatient basis allowing a rapid return to normal activities. If it can be made more effective, it has the potential to provide better local control, while improving functional outcome.

Cite this article: Bone Joint J 2014;96-B:1540–5.

We investigated the eventual diagnosis in patients referred to a tertiary centre with a possible diagnosis of a primary bone malignancy.

We reviewed our database from between 1986 and 2010, during which time 5922 patients referred with a suspicious bone lesion had a confirmed diagnosis. This included bone sarcoma in 2205 patients (37%), benign bone tumour in 1309 (22%), orthopaedic conditions in 992 (17%), metastatic disease in 533 (9%), infection in 289 (5%) and haematological disease in 303 (5%). There was a similar frequency of all diagnoses at different ages except for metastatic disease. Only 0.6% of patients (17 of 2913) under the age of 35 years had metastatic disease compared with 17.1% (516 of 3009) of those over 35 years (p < 0.0001). Of the 17 patients under 35 years with metastatic disease, only four presented with an isolated lesion, had no past history of cancer and were systematically well.

Patients under the age of 35 years should have suitable focal imaging (plain radiography, CT or MRI) and simple systemic studies (blood tests and chest radiography). Reduction of the time to biopsy can be achieved by avoiding an unnecessary investigation for a primary tumour to rule out metastatic disease.

Pathological fractures in children can occur as a result of a variety of conditions, ranging from metabolic diseases and infection to tumours. Fractures through benign and malignant bone tumours should be recognised and managed appropriately by the treating orthopaedic surgeon. The most common benign bone tumours that cause pathological fractures in children are unicameral bone cysts, aneurysmal bone cysts, non-ossifying fibromas and fibrous dysplasia. Although pathological fractures through a primary bone malignancy are rare, these should be recognised quickly in order to achieve better outcomes. A thorough history, physical examination and review of plain radiographs are crucial to determine the cause and guide treatment. In most benign cases the fracture will heal and the lesion can be addressed at the time of the fracture, or after the fracture is healed. A step-wise and multidisciplinary approach is necessary in caring for paediatric patients with malignancies. Pathological fractures do not have to be treated by amputation; these fractures can heal and limb salvage can be performed when indicated.

Between 1988 and 2006, 18 patients had a custom-made endoprosthetic replacement of the distal humerus for bone tumours at our institution. There were 11 primary malignant neoplasms, six secondary deposits, and one benign aggressive tumour. The mean follow-up was for 4.4 years (1 to 18.2). Complications occurred in nine patients and included aseptic loosening in three (16.6%), local recurrence in two (11%), infection in two (11%), neuropraxia of the radial nerve in one (5.5%) and a peri-prosthetic fracture in one (5.5%). Excision was inadequate in four patients (22%), all of which developed local recurrence and/or metastases. There were seven deaths from the primary disease after a mean of 2.3 years (1 to 5), one of whom had an above-elbow amputation for local recurrence seven months before death. The remaining six had satisfactory elbow function at their last follow-up. The 11 living patients were evaluated using the Musculoskeletal Tumour Society and Toronto Extremity Salvage scoring systems. The mean scores achieved were 76% (67% to 87%) and 73% (59% to 79%), respectively. Overall, 17 of 18 patients had significant improvement in the degree of their pain following operation.

Custom-made endoprosthetic reconstruction of the elbow for bone tumours is a viable treatment in carefully selected patients. It maintains satisfactory function and provides good pain relief.

The most appropriate protocol for the biopsy of musculoskeletal tumours is controversial, with some authors advocating CT-guided core biopsy. At our hospital the initial biopsies of most musculoskeletal tumours has been by operative core biopsy with evaluation by frozen section which determines whether diagnostic tissue has been obtained and, if possible, gives the definitive diagnosis. In order to determine the accuracy and cost-effectiveness of this protocol we have undertaken a retrospective audit of biopsies of musculoskeletal tumours performed over a period of two years.

A total of 104 patients had biopsies according to this regime. All gave the diagnosis apart from one minor error which did not alter the management of the patient. There was no requirement for re-biopsy. This protocol was more labour-intensive and 38% more costly than CT-guided core biopsy (AU$1804 vs AU$1308). However, the accuracy and avoidance of the anxiety associated with repeat biopsy outweighed these disadvantages.