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.

MUTARS® Humero pro Femur replacement: A novel reconstructive procedure after malignant bone tumor resection of the femur in young children.

Limb-preserving surgery in young children suffering malignant bone tumor of the femur is challenging due to the specific anatomical conditions. Extendable tumor endoprostheses are often oversized, while custom-made endoprostheses do not provide the intraoperatively required variability regarding reconstruction length. Allo- and autograft replacements, on the other hand, show high complication and revision rates. We report a novel reconstructive procedure after resection of malignant bone tumors of the femur in young children, and present our preliminary results of this technique.

Aneurysmal bone cyst of the pelvis and sacrum: a single-center study of 17 cases.

BACKGROUND: The aneurysmal bone cyst (ABC) is a benign, but locally aggressive cystic lesion of the bone. It usually occurs in the metaphysis of long bones of adolescents and young adults but can also affect the pelvis. METHODS: This single-center study is a retrospective review of 17 patients with primary ABCs of the pelvis. It examines the importance of polidocanol instillations as minimally invasive treatment option for ABCs of the pelvis compared to intralesional curettage or marginal resection. RESULTS: Seventeen patients with the diagnosis of a primary ABC of the pelvis were included in the study. Six patients were male (35%) and 11 patients female (65%); the mean age was 18 (9-49) years. The mean follow-up time was 50 months (12-136 months). The most common location of manifestation was the pubis (6; 35%), followed by the ilium (6; 35%), the sacrum (3; 18%) and the ischium (2; 12%). Eight patients were treated by intralesional curettage with the use of adjuvants, one patient by marginal resection, seven by sequential instillation of polidocanol and one patient by simple observation. Five patients received an additional transarterial embolization. After intralesional curettage local recurrence was detected in 4/8 cases (50%). After instillation therapy six patients (86%) had a stable disease without recurrence, only one patient (14%) had a persistent disease with need of additional treatment and was therefore converted to intralesional curettage without local recurrence in the follow-up. CONCLUSIONS: Sequential instillations of polidocanol are a promising, minimally invasive treatment method for ABCs of the pelvis and can be well combined with transarterial embolization.

Giant cell tumor of bone: A single center study of 115 cases.

BACKGROUND: Giant cell tumor of bone (GCTB) is a locally aggressive bone tumor that represents about 4-5% 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 may include intralesional curettage with adjuvants or, in rare cases, wide resection. In recent years the monoclonal antibody denosumab has been introduced as a potential (neo-)adjuvant systemic treatment option for patients with borderline resectable or unresectable lesions. Currently several studies reported that the use of denosumab prior to curettage possibly increase the risk of local recurrence. METHODS: In this retrospective study we reviewed 115 cases of GCT with a mean follow-up of 65.6 (24-404) months who underwent a surgical treatment with or without preoperative denosumab therapy in our institution. Potential risk factors for LR and complications were analyzed. RESULTS: The study includes 47 male (40.9%) and 68 female (59.1%) patients with a mean age of 33.9 (10-77) years and a mean follow-up of 65.6 (24-404) months. Denosumab was used in 33 (28.7%) cases, in 14 cases (12.2%) in a neoadjuvant setting and in 17 cases preoperatively before re-curettage (14.8%) after LR. In 105 cases (91.3%) an intralesional curettage was performed. The overall LR rate was 47.8% (55 cases). Patients who underwent intralesional curettage and bone cement augmentation without neoadjuvant denosumab treatment had LR in 42.2% (38/90) of the cases. Patients who underwent neoadjuvant denosumab treatment prior to curettage had LR in 28.6% (4/14). Re-recurrence was frequent in patients with neoadjuvant denosumab treatment who had LR after initial curettage (50%, 8/16). After wide resection and endoprosthetic replacement one case (20%) of local recurrence was detectable (1/5 cases). CONCLUSIONS: GCTB recurs frequently after intralesional curettage and cement augmentation. While denosumab is a potential (neo-)adjuvant treatment option that might be used for lesions that are difficult to resect, surgeons should be aware that LR is still frequent.

Aneurysmal bone cyst of the foot: A series of 10 cases.

BACKGROUND: Aneurysmal bone cyst (ABC) is a benign, locally aggressive tumor that occurs in childhood and early adulthood. It usually affects the metaphysis of long bones but can also occur in the foot. METHODS: This single-center study is a retrospective review of ten patients with primary ABCs of the foot which underwent an intralesional curettage or a polidocanol instillation. RESULTS: After intralesional curettage a local recurrence was observed in 3/5 cases. The instillation of polidocanol showed a significant reduction of the initial cyst volume (p=0.0267). In the instillation subgroup a primary complete healing was achieved in three cases. Due to a persisting disease two cases were converted to intralesional curettage without local recurrence in the follow-up. CONCLUSIONS: Percutaneous instillation of polidocanol is a minimally invasive treatment option for ABCs of the foot and especially for small bones. Nevertheless, several sequential instillations and a conversion to intralesional curettage can be necessary.

Current strategies for the treatment of solitary and aneurysmal bone cysts: A review of the literature.

This review of the literature aims to compare the etiology, the pathogenesis, the clinical diagnostics and the relevant treatment options of two different types of cystic bone lesions: the solitary bone cyst (SBC) and the aneurysmal bone cyst (ABC). Whereas the clinical symptoms and the radiographic appearance can be similar, the diagnostic pathway and the treatment options are clearly different. The solitary bone cyst (SBC) represents a tumor-like bone lesion, occurring most frequently in the humerus and femur in children and adolescents. Pain caused by intercurrent pathological fractures is often the first symptom, and up to 87% of the cysts are associated with pathological fractures. In the majority of cases SBCs can be treated conservatively, especially in the upper extremity. However, if a fracture is completely dislocated, joint affecting, unstable or open, surgical treatment is necessary. Pain under weight bearing or regaining the ability to mobilize after fracture timely can necessitate surgical treatment in SBCs affecting the lower extremity. Spontaneous resolution can be seen in rare cases. The aneurysmal bone cyst (ABC) is a benign, locally aggressive tumor that occurs in childhood and early adulthood. It usually affects the metaphysis of long bones but can also occur in the spine or the pelvis. ABC can be primary but also secondary to other bone pathologies. The diagnosis has to be confirmed by biopsy and histopathological examinations. With cytogenetic studies and the detection of specific translocations of the ubiquitin-specific protease (USP) 6 gene primary ABCs can be differentiated from secondary ABCs and other bone lesions. Among various modalities of treatment i.e. en bloc resection, intralesional curettage with adjuvants, embolization or the systemic application of denosumab, intralesional sclerotherapy using polidocanol is an effective and minimally invasive treatment of primary ABCs.

Evaluation of different treatment modalities for fractured and non-fractured simple bone cyst: A single-center review of 68 patients.

ABSTRACT: Simple bone cysts (SBCs) occur most frequently in the proximal aspect of the humerus and femur in growing age and are associated with intercurrent pathological fractures in up to 87%. Therapeutic management of SBCs remains controversial. The aim of this study was to examine the outcome of conservative and various surgical treatment modalities considering the specific anatomic location and integrity of the SBC.In this retrospective study, we analyzed 68 cases of SBCs who underwent a conservative or surgical treatment between 2009 and 2020 with a mean follow-up of 30.1 months. The epidemiological characteristics, complications, clinical, and radiographic outcome after conservative or surgical treatment were assessed.The study includes 50 male (73.5%) and 18 female (26.5%) patients with a mean age of 9.1 years. The most common locations were the proximal humerus (69.2%, n = 47) and femur (16.2%, n = 11). In 43 cases (63.2%; upper limb n = 40, lower limb n = 3) a pathological fracture occurred. Fifty patients (73.5%; upper limb n = 40, lower limb n = 10) underwent a conservative treatment. In 11 cases (16.2.1%; upper limb n = 4, lower limb n = 7) an intralesional curettage and defect reconstruction with bone substitute without stabilization were performed. Five patients (7.3%; upper limb n = 4, lower limb n = 1) received an osteosynthesis, in two cases (2.9%; upper limb 1; lower limb 1) combined with an intralesional curettage and defect reconstruction with bone substitute. All 32 pathological fractures treated conservatively (upper limb n = 31, lower limb n = 1) healed within 6 weeks; 17/43 patients (39.5%) suffered at least one second fracture. After intralesional curettage and defect reconstruction with bone substitute local recurrence was observed in 5/13 cases (38.5%). Spontaneous consolidation, at least partially, was observed in three cases (4.4%) following conservative treatment after fracture. No relevant secondary angular or torsional deformity was observed after treatment.The majority of SBCs can be treated conservatively, especially in the upper extremity. However, if a fracture is completely dislocated, joint affecting, unstable or open, surgical treatment is necessary. Load-dependent pain or the inability to mobilize timely after fracture can necessitate surgical treatment in SBCs affecting the lower extremity. Spontaneous resolution, especially after fracture, can be seen in rare cases.

Complex Bone Tumors of the Trunk-The Role of 3D Printing and Navigation in Tumor Orthopedics: A Case Series and Review of the Literature.

The combination of 3D printing and navigation promises improvements in surgical procedures and outcomes for complex bone tumor resection of the trunk, but its features have rarely been described in the literature. Five patients with trunk tumors were surgically treated in our institution using a combination of 3D printing and navigation. The main process includes segmentation, virtual modeling and build preparation, as well as quality assessment. Tumor resection was performed with navigated instruments. Preoperative planning supported clear margin multiplanar resections with intraoperatively adaptable real-time visualization of navigated instruments. The follow-up ranged from 2-15 months with a good functional result. The present results and the review of the current literature reflect the trend and the diverse applications of 3D printing in the medical field. 3D printing at hospital sites is often not standardized, but regulatory aspects may serve as disincentives. However, 3D printing has an increasing impact on precision medicine, and we are convinced that our process represents a valuable contribution in the context of patient-centered individual care.

Primary Aneurysmal Bone Cyst and Its Recent Treatment Options: A Comparative Review of 74 Cases.

(1) Background: An aneurysmal bone cyst (ABC) is a benign, locally aggressive tumor. Different treatment modalities are described in the literature i.e., en bloc resection, intralesional curettage and percutaneous sclerotherapy. (2) Methods: This single-center study is a review of 74 patients with primary ABCs who underwent a surgical treatment or polidocanol instillation. Cyst volume measurements using MRI and conventional radiographs are compared. (3) Results: The mean pre-interventional MRI-based cyst volume was 44.07 cm3 and the mean radiographic volume was 27.27 cm3. The recurrence rate after intralesional curettage with the need for further treatment was 38.2% (13/34). The instillation of polidocanol showed a significant reduction of the initial cyst volume (p < 0.001) but a persistent disease occurred in 29/32 cases (90.6%). In 10 of these 29 cases (34.5%) further treatment was necessary. After en bloc resection (eight cases) a local recurrence occurred in two cases (25%), in one case with the need for further treatment. (4) Conclusions: MRI scans are superior to biplanar radiographs in the examination of ABCs. Sequential percutaneous instillations of polidocanol are equally effective in the therapy of primary ABCs compared to intralesional curettage. However, several instillations have to be expected. In a considerable number of cases, a conversion to intralesional curettage or en bloc resection may be necessary.

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

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.

Aneurysmal bone cyst inadvertently treated with chemotherapy-A series of three cases.

Aneurysmal bone cyst (ABC) is a benign locally aggressive tumor that occurs in childhood and early adulthood. Most relevant differential diagnoses are the telangiectatic osteosarcoma and the giant cell tumor. In the present case series chemotherapy following the EURAMOS or the Euro-Ewing 99 protocol was externally applied in three patients with the misdiagnosis of ABC as malignant bone tumor. In all three cases, a significant reduction of the volume of the ABC was achieved. This is the first report about the use of neoadjuvant chemotherapy in ABC. Chemotherapy reduces the size of an ABC and leads to progressive sclerosis.

Comparative Analysis of Impairment Ratings From the 5th to 6th Editions of the AMA Guides.

OBJECTIVE: The association of American Medical Association's (AMA) Guides edition with impairment ratings is uncertain. METHODS: We used data from a consecutive sample of 249 injured workers referred for an independent evaluation 10 months before and after assessors switched from the 5th to the 6th edition of the AMA Guides. RESULTS: The median whole person impairment rating was 7.0% (interquartile range [IQR]: 4 to 14) for 131 claimants assessed with the 5th edition of the Guides, and 4.0% (IQR: 2 to 8) for 118 claimants assessed with the 6th edition (P-value for difference: 0.002). Multivariable analysis showed a 36.4% relative reduction (95% confidence interval [CI] 17.2% to 57.3%) in impairment rating with the 6th edition of the Guides versus the 5th edition. CONCLUSIONS: The 6th edition of the AMA Guides provides systematically lower impairment ratings for injured workers than the 5th edition.