Controversies in orthopaedic oncology.

Chondrosarcoma is the second most common surgically treated primary bone sarcoma. Despite a large number of scientific papers in the literature, there is still significant controversy about diagnostics, treatment of the primary tumour, subtypes, and complications. Therefore, consensus on its day-to-day treatment decisions is needed. In January 2024, the Birmingham Orthopaedic Oncology Meeting (BOOM) attempted to gain global consensus from 300 delegates from over 50 countries. The meeting focused on these critical areas and aimed to generate consensus statements based on evidence amalgamation and expert opinion from diverse geographical regions. In parallel, periprosthetic joint infection (PJI) in oncological reconstructions poses unique challenges due to factors such as adjuvant treatments, large exposures, and the complexity of surgery. The meeting debated two-stage revisions, antibiotic prophylaxis, managing acute PJI in patients undergoing chemotherapy, and defining the best strategies for wound management and allograft reconstruction. The objectives of the meeting extended beyond resolving immediate controversies. It sought to foster global collaboration among specialists attending the meeting, and to encourage future research projects to address unsolved dilemmas. By highlighting areas of disagreement and promoting collaborative research endeavours, this initiative aims to enhance treatment standards and potentially improve outcomes for patients globally. This paper sets out some of the controversies and questions that were debated in the meeting.

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.

Bone biopsy results in patients with a history of malignancy: a case series of 378 patients.

OBJECTIVE: The value of a bone biopsy in patients who present with a bone lesion and past medical history of malignancy is uncertain. The objective of this study was to evaluate the outcome of bone biopsies in patients with a history of a malignancy undergoing bone biopsy of a lesion in a regional bone tumour unit. Secondary outcomes include the assessment of survival in the different outcome groups. MATERIALS AND METHODS: This was a retrospective study of patients, with a previous malignancy and suspicious bone lesions, who underwent bone biopsy for final diagnosis between March 2010 and September 2019. Results of the biopsy were summarized into 3 groups: confirmed original malignancy, confirmed benign diagnosis, and confirmed new malignancy. Survival analysis of each group was also undertaken. RESULTS: A total of 378 patients met the inclusion criteria (mean age 64 years, 216 females (57%)). In 250 cases (66%), the original malignancy was confirmed on the bone biopsy; in 128 cases, an alternative diagnosis was confirmed (benign diagnosis in 69 (18%)), and 59 had a new malignancy (16%). Survival was significantly greater for those in whom a benign diagnosis was confirmed (logrank test p = 0.0100). CONCLUSION: This study shows that for patients presenting with a suspicious bone lesion, together with a history of malignancy, in a third of cases, the bone biopsy will confirm an alternative diagnosis of a benign lesion or a new malignancy. Survival of these patients will vary significantly depending on the biopsy outcome.

Prediction of pathological fracture in patients with metastatic disease of the lower limb.

The aim of this study was to investigate if the risk of pathological fracture can be predicted with the proportion of body weight that can be put through the affected leg in patients with metastatic bone disease of the lower limb. A prospective observational study was conducted in patients with metastatic disease in the lower limb. Receiver Operator Characteristic curves were used to identify the optimum threshold level of single stance weight bearing to predict fracture and compared to the Mirels score. Patients who underwent surgery could weight bear significantly less than those who did not have surgical intervention. The optimum threshold to predict pathological fracture was 85% of total body weight. No patient below the threshold level of 85% single stance body weight sustained a pathological fracture. The use of single stance body weight can be a useful in conjunction with the Mirels score to predict pathological fracture. If less than 85% of total body weight can be put through the affected limb, the risk of fracture increases, and consideration of treatment is suggested.

Osteobastoma of the Talus: A case report and review of the literature.

Osteoblastoma is benign bone forming tumour with rare malignant transformation. The common locations include spine, proximal humerus and hip. It rarely affects the talus. A case of osteoblastoma of the talus in a 33-years old healthy male who presented to the foot and ankle clinic in October 2015 complaining of pain of the right ankle for 12 months following football injury is discussed.

Unusual lesions mimicking impingement syndrome in the shoulder joint - Think medially.

Impingement syndrome is usually caused by irritation of the rotator cuff within the sub acromial space and this includes the coraco-acromial arch (Acromion and Coraco-acromial ligament), the acromio-clavicular joint and occasionally the coracoid. Iatrogenic causes such as sutures, pins, plates or wires left from previous surgery can cause similar symptoms. We present a series of four cases mimicking "classical" impingement symptoms/signs in which the causal pathology was identified outside the sub-acromial space. Magnetic Resonance Imaging (MRI) showed lesions that were present in the supra-spinatus fossa but were causing pressure effects on the sub-acromial space, namely - a ganglion cyst in one case, lipomata in two other cases, and a glomus tumour. A ganglion cyst and glomus tumour mimicking impingement syndrome is a rare reported case to our knowledge. These are unusual causes that should be considered when investigating classical impingement syndrome and particularly those who may have failed to respond to decompression surgery. They highlight the potential value of looking beyond the sub-acromial space for causal lesions and in these cases, at a time when limited ultrasound investigation has become increasingly popular; MRI has clearly played an important and was essential in planning surgery as these lesions would not have been identified on USS. Even though the symptoms were classical.

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.

Accuracy of magnetic resonance imaging in planning the osseous resection margins of bony tumours in the proximal femur: based on coronal T1-weighted versus STIR images.

OBJECTIVE: Assessment of the extent of tumours using magnetic resonance imaging (MRI) is the basis for bone resection in limb-salvage surgery. We aimed to compare the accuracy of T1-weighted MRI and STIR sequences in measuring the extent of proximal femoral tumours, using the macroscopic specimens as the gold standard for comparison. MATERIALS AND METHODS: We compared single coronal T1-weighted with STIR sequences in 34 proximal femoral tumours, using bivalved resected macroscopic tumours for comparison. After randomisation, four observers measured longitudinal osseous tumour extent using MRI and specimen photographs on two separate occasions, 3 weeks apart. RESULTS: There were 25 metastatic tumours, 8 chondrosarcomas and 1 myeloma. Eight patients presented with pathological fractures. The Pearson's correlation coefficient for comparison of T1 with macroscopic tumours was 0.91 (95% confidence interval [CI]: 0.83 to 0.96) for all observers and 0.90 (95% CI: 0.81 to 0.95) for STIR images. This difference was not statistically significant, and T1 and STIR sequence measurements had similar precision and accuracy. Bland-Altman plots showed T1-weighted imaging to be unbiased, whereas STIR sequences were biased and had systematic error. Moreover, STIR measurements overestimated tumour size by 6.4 mm (95% CI: -26.9 to 39.7 mm) and 2 patients were outliers. T1 measurements were closer to the macroscopic measurements with a mean difference of 1.3 mm (95% CI: -28.9 mm to 31.5 mm), with 3 patients falling outside of this. The variance was greater for STIR measurements. This difference between T1 and STIR measurements was statistically significant (p = 0.000003). The intra-observer reliability between separate measurements for MRI and specimen photographs achieved interclass correlation coefficients of 0.97, 0.96 and 0.95 (T1, STIR and macroscopic tumour respectively). T1 had greater interobserver correlation than for STIR and macroscopic tumour measurements (0.88 vs 0.85 and 0.85 respectively). These differences in interclass correlation were not statistically significant. CONCLUSION: This study has shown T1-weighted MRI sequences to be unbiased compared with STIR sequences at determining intra-osseous tumour extent. STIR overestimates the length of bone tumours. T1 is therefore preferred for pre-operative planning for the resection of bone tumours.

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

OBJECTIVE: To assess the safety and effectiveness of image-guided radiofrequency ablation (RF ablation) in the treatment of chondroblastomas as an alternative to surgery. MATERIALS AND METHODS: Twelve patients with histologically proven chondroblastoma at our institution from 2003 to date. We reviewed the indications, recurrences and complications in patients who underwent RF ablation. RESULTS: Twelve patients were diagnosed with chondroblastoma. Out of these, 8 patients (6 male, 2 female, mean age 17 years) with chondroblastoma (mean size 2.7 cm) underwent RF ablation. Multitine expandable electrodes were used in all patients. The number of probe positions needed varied from 1 to 4 and lesions were ablated at 90 °C for 5 min at each probe position. The tumours were successfully treated and all patients became asymptomatic. There were no recurrences. There were 2 patients with knee complications, 1 with minor asymptomatic infraction of the subchondral bone and a second patient with osteonecrosis/chondrolysis. CONCLUSION: Radiofrequency ablation appears to be a safe and effective alternative to surgical treatment with a low risk of recurrence and complications for most chondroblastomas. RF ablation is probably superior to surgery when chondroblastomas are small (less than 2.5 cm) with an intact bony margin with subchondral bone and in areas of difficult surgical access.

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.

The outcome of locking plate fixation for the treatment of periarticular metastases.

Periarticular bone metastasis may be treated with endoprosthetic reconstruction. The extensive surgery required may not, however, be appropriate for all patients. Our aim was to establish whether locking plates provide good functional outcomes and a durable construct when used in the management of metastatic disease. Prospective data collection was performed. Twenty one patients underwent surgery for periarticular metastatic tumours. The median duration of followup for surviving patients is one year. There have been no cases of implant failure and no requirement for revision surgery. Pain relief was excellent or good in the majority of patients. Patients who had sustained a fracture prior to fixation had restoration of their WHO performance status. All patients had a dramatic improvement in their MSTS scores. The median pre-operative score was 15% (0%-37%) improving to a median score of 80% (75%-96%) post operatively. Locking plates were found to provide reliable fixation and excellent functional restoration in selected patients suffering from periarticular metastatic bone disease.