Musculoskeletal Oncology Research Articles

"Treatment of Pathologic Fracture of Femoral Shaft with Abrasion of the Lytic Lesion, Open Reduction, Cement Infusion and Internal Fixation; A Case Report"

Pathological fractures are a rising concern in the field of musculoskeletal oncology. Their incidence rises, mainly due to the improved diagnostic and therapeutic methods that lead to prolonged survival. The appropriate treatment has not been yet standardized, but the current bibliography describes surgical treatment capable of stabilizing the expected life expectancy. Orthopedic cement infusion in combination with broad abrasion of the bone metastasis has been described, although more research is needed.

Teaching Potential of Multidisciplinary Tumor Board Meetings for Orthopedic Residents: Insights From a French Sarcoma Reference Center.

Multidisciplinary tumor boardmeetings (MTBMs) have been established in oncology to improve patient care. While their benefits for patients have been well-documented, there are no previous studies on the teaching opportunities they provide for residents and medical students. This study aimed to examine the teaching provided to residents during MTBM and identify areas for improvement. The study hypothesized that although the primary objective of MTBM is not teaching, they could still contribute to residents' learning. The study focused on the tumors board meeting for bone metastasis and musculoskeletal tumors/sarcoma in a French reference center for musculoskeletal oncology. The composition of the MTBM included specialists from various disciplines, and it convened on a weekly basis to discuss cases. The orthopedic oncology residents (OORs) actively participated in the MTBM as part of their training. A questionnaire was distributed to OORs who had served between 2014 and 2021, and their responses were analyzed. The results showed that the OOR perceived MTBM as interesting, beneficial for their training, and challenging. While opinions were divided on whether MTBM was a suitable place for education, the majority believed it improved their knowledge of different specialties and provided valuable elements applicable to daily practice. They also felt it facilitated future access to MTBs if needed. OORs recommended the rotation as an orthopedic oncology resident to younger residents. Recommendations for improvement included incorporating more dedicated teaching time, active involvement of residents in the learning process, availability of learning materials, and post-MTBM debriefing sessions. The study highlighted the importance of case presentations, public speaking skills, interdisciplinary collaboration, and clinical reasoning observed during MTBM. In conclusion, while not primarily designed for teaching, MTBM offers valuable learning opportunities for residents. Enhancing the teaching experience through dedicated debriefing sessions, resident involvement, and improved support can further optimize their educational impact. Future evaluations are needed to assess the effectiveness of these improvements. This study provides insights into the teaching potential within MTBM and can guide educational initiatives in the field of oncology.

Trends in ACGME Accreditation of Orthopedic Surgery Fellowship Training.

Currently, most surgeons pursue subspecialty fellowship training. This study answers the following questions: (1) How does the rate of fellowship training in orthopedic surgery compare with that in other surgical specialties? (2) To what extent did adoption of Accreditation Council for Graduate Medical Education (ACGME) accreditation change from 2013 to 2021? Orthopedic subspecialties were analyzed for total number of fellowship programs and positions in the 2013 and 2021 Match. Rates of ACGME accreditation were analyzed via chi-square tests. In 2021, orthopedic surgery had the highest rate of fellowship selection (94%) relative to general surgery (77%), ophthalmology (66%), plastic surgery (63%), and otolaryngology (55%). Across all orthopedic subspecialties, the percentage of ACGME accreditation decreased among fellowship programs (53% in 2013 to 48% in 2021, P=.166) and positions (58% in 2013 to 50% in 2021, P<.001). Orthopedic sports medicine had the highest adoption of ACGME accreditation (100%), followed by hand surgery (99%), musculoskeletal oncology (67%), and pediatric orthopedics (56%). Significant increases in the adoption of ACGME accreditation were noted for orthopedic sports medicine (93% in 2013 to 100% in 2021, P=.016) and hand surgery (81% in 2013 to 99% in 2021, P<.001). There was a significant decrease in ACGME accreditation for adult reconstructive orthopedics (40% in 2013 to 24% in 2021, P=.042), driven by the increase in unaccredited fellowship programs. Accreditation of orthopedic subspecialty fellowship training has decreased with respect to the proportion of accredited training positions. More research is needed to understand the benefits of ACGME accreditation for fellowship training in orthopedic surgery. [Orthopedics. 2024;47(1):57-63.].

Whole-Body MRI in Musculoskeletal Oncology: A Comprehensive Review with Recommendations.

Whole-body (WB) MRI has emerged as an attractive method for oncologic evaluation, potentially replacing conventional imaging modalities and providing a one-step wide-coverage assessment of both the skeleton and soft tissues. In addition to providing anatomic information, WB MRI may also yield a functional analysis with the inclusion of diffusion-weighted imaging (DWI). DWI translates microstructural changes, resulting in an excellent alternative to fluorodeoxyglucose PET/CT. WB MRI (with DWI) offers comparable accuracy to PET/CT and has the advantage of avoiding ionizing radiation. Technological advances and the development of faster protocols have prompted greater accessibility of WB MRI, with growing applications in routine practice for the diagnosis, staging, and follow-up of cancer. This review discusses the technical considerations, clinical applications, and accuracy of WB MRI in musculoskeletal oncology. Keywords: Pediatrics, MR Imaging, Skeletal-Axial, Skeletal-Appendicular, Soft Tissues/Skin, Bone Marrow, Extremities, Oncology, Musculoskeletal Imaging © RSNA, 2023.

Clinical Benefits of LigaSure™ for Surgical Amputation Without Tourniquet Use in Patients With Musculoskeletal Tumor.

Amputation is still a viable option for musculoskeletal tumors that are multi-compartmental, adjacent to neurovascular structures, and involving pathological fractures. Complications such as poor surgical margins, local recurrence and infection after limb salvage surgery are also indications for secondary amputation. An effective hemostatic technique is vital for preventing complications of massive blood loss and prolonged operative time. The use of LigaSure™ in the field of musculoskeletal oncology has not been well documented. This retrospective study included 27 patients with musculoskeletal tumor who underwent amputation using either LigaSure™ system (n=12) or traditional hemostatic technique (n=15) from 1999 to 2020. The purpose of this study was to evaluate the effect of LigaSure™ in terms of intra-operative blood loss, blood transfusion rates, and duration of surgery. The use of LigaSure™ resulted in a significant decrease in intraoperative blood loss (p=0.027) and blood transfusion rates (p=0.020). There was no significant difference for the duration of surgery between the two groups (p=0.634). The LigaSure™ system can potentially improve clinical outcomes in patients with musculoskeletal tumor undergoing amputation surgeries. The LigaSure™ system is a safe and effective hemostatic tool for musculoskeletal tumor amputation surgeries.

Clinical Outcome of Low-Grade Myofibroblastic Sarcoma in Japan: A Multicenter Study from the Japanese Musculoskeletal Oncology Group

This retrospective multicenter study aimed to analyze the clinical features and prognosis of 24 patients diagnosed with LGMS between 2002 and 2019 in the Japanese sarcoma network. Twenty-two cases were surgically treated and two cases were treated with radical radiotherapy (RT). The pathological margin was R0 in 14 cases, R1 in 7 cases, and R2 in 1 case. The best overall response in the two patients who underwent radical RT was one complete response and one partial response. Local relapse occurred in 20.8% of patients. Local relapse-free survival (LRFS) was 91.3% at 2 years and 75.4% at 5 years. In univariate analysis, tumors of 5 cm or more were significantly more likely to cause local relapse (p &lt; 0.01). In terms of the treatment of relapsed tumors, surgery was performed in two cases and radical RT was performed in three cases. None of the patients experienced a second local relapse. Disease-specific survival was 100% at 5 years. A wide excision aimed at the microscopically R0 margin is considered the standard treatment for LGMS. However, RT may be a viable option in unresectable cases or in cases where surgery is expected to cause significant functional impairment.

Injectable Synthetic Beta-Tricalcium Phosphate/Calcium Sulfate (GeneX) for the Management of Contained Defects Following Curettage of Benign Bone Tumours.

Benign and low-grade malignant bone tumours are often treated with curettage and filling of the resultant defect using any of a number of materials, including autologous bone grafts, allografts, or synthetic materials. The objective of this study was to report our experience using a synthetic bone graft substitute in these patients. Ten consecutive cases (four males, six females; mean age, 36 years) of benign bone tumours were treated surgically at a tertiary musculoskeletal oncology centre, between 2019 and 2021. Following curettage, the contained defects were managed with injectable beta-tricalcium phosphate/calcium sulfate (GeneX; Biocomposites Ltd., Keele, UK). The desired outcomes were early restoration of function and radiographic evidence of healing. No other graft materials were used in any of the patients. The mean follow-up was 24 months (range, 20-30 months). All patients in this series (100%) demonstrated radiographic evidence of healing and resumed their daily living activities. There were no tumour recurrences and no complications were encountered with the use of GeneX. In patients with contained defects following curettage of benign bone tumours, we found GeneX to be a safe and effective filling agent. These findings contrast with some existing studies that have reported local complications with the use of injectable beta-tricalcium phosphate/calcium sulfate.

Diversity in Leadership at Musculoskeletal Oncology Fellowships in the United States.

Musculoskeletal oncology fellowship directors (MOFDs) possess the unique ability to influence treatment paradigms in musculoskeletal oncology through teaching and research. Currently, the characteristicsthat define this important role including demographics, training characteristics, research activity, and grant funding are poorly defined. A list of musculoskeletal oncology fellowship programs was obtained from the American Association of Hip and Knee Surgeons and Musculoskeletal Oncology Fellowship Match. Bibliometric data including the h-index were abstracted from Scopus. Demographics, training, and federal grant characteristics were collected from academic websites. Comparisons were made using t-tests and data were presented as means ± SD. The average age at the appointment was 41±9 years and most were male (80%) and Caucasian (85%). Few had an additional graduate degree (10% MS, 5% PhD). The mean h-index was 23±15 resulting from 91±56 publications. There was a positive correlation between age and h-index (r=0.398, p=0.082). Four MOFDs (20%) had at least one National Institutes of Health research grant. Sex, race, additional graduate degree, and procurement of NIH funding were not associated with higher h-index values. Full professors had higher h-index values than assistant/associate professors (p=0.014). Women and racial minorities are underrepresented among leadership positions in musculoskeletal oncology fellowship programs. This study can help provide a benchmark for departments in orthopedic surgery and aspiring orthopedic surgeons for MOFD positions.

Correction to: Influence of Accuracy and Precision of Measurements of Long Bone Tumors in Imaging Studies—A Retrospective Study in Musculoskeletal Oncology

Correction to: Influence of Accuracy and Precision of Measurements of Long Bone Tumors in Imaging Studies—A Retrospective Study in Musculoskeletal Oncology

Influence of Accuracy and Precision of Measurements of Long Bone Tumors in Imaging Studies-A Retrospective Study in Musculoskeletal Oncology.

The aim of this study is to evaluate the level of accuracy and precision of bone scan (BS), MRI, and digital radiography (DR) to measure long bone tumors to design custom-made prosthesis (CMP)/modular prosthesis (MP) in limb salvage surgery (LSS) with the help of phantom and patient's study. There are two separate groups: one is the phantom study and another one is the patient's study. The phantom study is done with the Jaszack Phantom for the Gamma camera and the indigenous phantom for the MRI and DR. Three independent imaging professionals (nuclear medicine physicians and radiologists) measured the distance between standardized, preselected points on the Jaszack phantom in the Gamma Camera (GC) and indigenous phantom on the coronal and sagittal view of the MRI scan and in digital radiography. The measured values were compared with the known values for phantom measurement. A total of 36 patients, which include 24 males and 12 females, 3 independent imaging professionals measured the patient's long bone in a bone scan, MRI and DR and compared it with histopathological specimen measurement after limb salvage surgery (LSS). Descriptive statistics using appropriate measures of central tendency and dispersion were employed to describe the data. Karl-Pearson correlation coefficient was used to establish the association between continuous covariates. Paired t-test was utilized to test the differences in paired values for statistical significance. A near-perfect positive correlation was evident between all three pairs of bone scan, MRI scan, and digital radiography values, and a positive agreement within 1mm of the bone scan, MRI scan, and DR values of all three pairs was around 95%. For the phantom study, we conclude that Gamma camera and MRI measurements are equal in physical measurements (MCF-1). DR measurements were found to be near equal physical measurements and multiplication correction factor (MCF)-0.9104 and three observer's measurements values were also near normal. For the patient's study, we conclude that the bone scan, MRI, and DR measurements of 3 independent imaging professionals are near normal, and it was confirmed with pathological specimen after LSS, to confirm reliability, repeatability, reproducibility, and accuracy of the tumor length to do custom-made prosthesis or modular prosthesis for the patients who are affected by osteosarcoma and Ewing's sarcoma.

Outcomes of management of primary benign aggressive or malignant bone tumors around the elbow by limb-salvage surgery

PurposeBone tumors around the elbow are rare, with frequently delayed diagnosis. The current study aimed to assess the functional and oncological outcomes of limb salvage surgery for primary benign aggressive or malignant bone tumors around the elbow.MethodsWe conducted a retrospective review of patients with primary aggressive benign and malignant bone tumors around the elbow treated with limb salvage surgery between 1995 and 2020 at a single musculoskeletal oncology center. The minimum follow-up period was 24 months. Functional results were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system at the last follow‐up visit. Local recurrence, chest metastasis, and complications were recorded.ResultsThis study included 30 patients, 19 males and 11 females, with a mean age of 25.4 ± 14.2 years. The tumor location was the distal humerus (n = 21), proximal radius (n = 5), and proximal ulna (n = 4). Reconstruction was done by elbow fusion using fibular graft (n = 10), mobile endoprosthesis (n = 9), excision arthroplasty (n = 7), and extracorporeal freezing and reimplantation (n = 4). The mean follow-up period was 36.2 ± 21.3 months. The median follow-up MSTS score was 27 [Interquartile range (IQR): 26–30]. Skeletally immature patients had a significantly higher MSTS score. The rate of postoperative complications was 26.7%.ConclusionLimb salvage surgery with different reconstructive options for benign aggressive and malignant bone tumors around the elbow can achieve good functional and oncological outcomes.Level of evidenceLevel IV.

Risk factors for local recurrence of giant cell tumor of bone of the extremities: a retrospective study

Background: Although considered as a benign tumor, giant cell tumor of bone (GCTB) has an aggressive biological behavior with high tendency for local recurrence (LR). The most commonly used method of treatment of GCTB is intralesional curettage augmented by various types of local adjuvants. The aim of this study was to evaluate the rate of recurrence of GCTB after surgical treatment to detect the risk factors that may influence the rate of LR. Methods: Fifty-two cases of GCTB that had been treated in a university hospital musculoskeletal oncology unit, between 2012 and 2017 were retrospectively reviewed after minimal follow-up of 4 yr and risk factors of LR were determined. Results: All LRs occurred within the first 3 yr (4 to 31 mo). Curettage was used to manage 34 patient cases, from which 11 patients (32.4%) showed LR. Only one patient (5.6%) of the 18 wide local excision patients developed recurrence. The highest recurrence rate was found among the lesions of the proximal femur. Neither the tumor volume nor the pathological grade had a significant impact on the rate of LR. The presence of soft-tissue invasion, occurrence of pathological fracture at presentation and using curettage as a method of treatment were associated with significantly higher rate of LR. Conclusions: Lesions in the proximal femur, occurrence of pathological fracture at presentation, soft-tissue invasion, and curettage as management option were found to be associated with an increased risk of LR of GCTB. Level of Evidence: Level III

Clinical Outcome in Patients With High-grade Soft-tissue Sarcoma Receiving Prosthetic Replacement After Tumor Resection of the Lower Extremities: Tokai Musculoskeletal Oncology Consortium Study.

This multicenter retrospective study aimed to clarify the surgical and oncological outcomes of patients with high-grade soft tissue sarcoma (STS) who underwent prosthetic replacement reconstruction after lower extremity tumor resection. We retrospectively collected the data of 27 patients with high-grade STS. The mean follow-up duration after prosthetic replacement was 44.7 months. The mean age at surgery was 63 years. The mean tumor size was 16 cm. For reconstruction, proximal femur replacement was performed in 15 patients, distal femur replacement in six, and total femur replacement in six. The major complications were infections in nine patients and aseptic loosening in four. Nine patients developed local recurrence. The cause of revision surgery was infection in five patients, aseptic loosening in three, and metal allergy in one. The 5-year prosthetic survival rate was 51.1%. At the final follow-up, amputation was performed in five patients. The 5-year limb salvage rate was 76.8%. The mean functional score of the 25 patients who could be assessed was 16.0 (53%). Of the 27 patients, five were excluded from the survival analysis because they underwent prosthetic replacement for local recurrence. The 5-year overall survival rate in the remaining 22 patients was 45.3%. We identified a high rate of surgical complications and poor survival in patients with high-grade STS who underwent tumor resection and reconstruction using prosthetic replacement of the lower extremities, although limb salvage was achieved in 81.5% of the patients. Careful follow-up is needed for surgical complications and oncological events after surgery.

Occupational injuries and burn out among orthopedic oncology surgeons.

Orthopedic oncology surgeons commonly engage in prolonged and complex surgical procedures. These types of surgeries increase the risk of physical and psychological stressors, which may in turn make these physicians prone to work-related occupational injuries. The aim of this study was to explore in orthopedic oncologists, the prevalence of work-related physical injuries and psychological disturbances. A modified version of the physical discomfort survey was developed to assess occupational injuries among orthopedic oncology surgeon members of the Musculoskeletal Tumor Society, the Canadian Orthopedic Oncology Society and European Musculoskeletal Oncology Societies. The survey was sent by email, and it explored musculoskeletal complaints, psychological disturbances, treatment required for these complaints and the requirement of time off work. A total of 67 surgeon responses were collected. A high number of orthopedic oncologists (84%) reported an occupational injury. Low back pain (39%) was the most prevalent musculoskeletal condition, followed by lumbar disk herniation (16%), shoulder tendinitis (15%) and lateral epicondylitis (13%). Of the cohort, 46% required surgery and 31% required time off work due to their injury. Thirty-three respondents reported a psychological disorder. Burnout (27%), anxiety (20%) and insomnia (20%) were the most commonly reported. Time required off work due to injury was associated with old age and years in practice. Orthopedic oncology surgeons report a high prevalence of work-related disorders. Lower back related injury and burnout were the most reported disorders. Improving operative room ergonomics and prevention of stress related to the work environment should be areas to explore in upcoming research.

Introduction to the special issue on imaging in musculoskeletal oncology

Introduction to the special issue on imaging in musculoskeletal oncology

Function and return to sports after proximal humeral replacement in patients with primary bone sarcoma

BackgroundImproved patient and limb survival rates have led to an increased interest in the functional outcome and return to sports of patients undergoing megaprosthetic reconstruction in musculoskeletal oncology. This study evaluates the functional outcome and postoperatively performed level of sports in patients undergoing proximal humeral replacement (PHR) following resection of a primary bone sarcoma and identifies potential beneficial and limiting factors.Patients and methodsBetween 2007 and 2020, a total of 606 patients underwent resection of a primary bone sarcoma and reconstruction with a single-design modular implant. For 112 (18%) patients, the location of the tumour was the proximal humerus. Exclusion criteria were death (n = 65), patients living overseas (n = 8), and subsequent amputation (n = 1), leaving 38 patients for evaluation, of whom 32 were available for the study (13 women, median age 42 years). Clinical data regarding oncological and surgical treatment as well as subsequent complications were obtained from the patients’ electronic medical records. Functional outcome was determined using the Musculoskeletal Tumor Society Score (MSTS) and Toronto Extremity Salvage Score (TESS) as well as the Subjective Shoulder Value (SSV). Return to sports was assessed using the Tegner Activity Score (TS) and the modified Weighted Activity Score (WAS).ResultsAt the last follow-up after a median of 30 months (IQR 22–58), median MSTS was 18 (IQR 12–24), median TESS was 80% (IQR 69–87), median SSV was 35% (IQR 10–58), median TS was 5 (IQR 4–6) and median WAS was 5 (IQR 0–10). Preservation of the axillary nerve, a reverse shoulder reconstruction and a WAS of > 10 prior to surgery were associated with better functional outcome and return to sports activity scores.ConclusionFollowing PHR, good to excellent functional outcomes are possible, and patients regularly return to participate in sports activities—most commonly in low-impact types of sports, but some individuals are even able to participate in high-impact sports activities.Level of evidenceIV.

Musculoskeletal oncology and thermal ablation: the current and emerging role of interventional radiology.

The role of interventional radiology (IR) is expanding. With new techniques being developed and tested, this radiology subspecialty is taking a step forward in different clinical scenarios, especially in oncology. Musculoskeletal tumoral diseases would definitely benefit from a low-invasive approach that could reduce mortality and morbidity in particular. Thermal ablation through IR has already become important in the palliation and consolidation of bone metastases, oligometastatic disease, local recurrences, and treating specific benign tumors, with a more tailored approach, considering the characteristics of every patient. As image-guided ablation techniques lower their invasiveness and increase their efficacy while the collateral effects and complications decrease, they become more relevant and need to be considered in patient care pathways and clinical management, to improve outcomes. We present a literature review of the different percutaneous and non-invasive image-guided thermal ablation methods that are currently available and that could in the future become relevant to manage musculoskeletal oncologic diseases.

What's New in Musculoskeletal Tumor Surgery.

What's New in Musculoskeletal Tumor Surgery.

Predictors of Functional Recovery among Musculoskeletal Oncology Patients Undergoing Lower Extremity Endoprosthetic Reconstruction.

Background and Objectives: Functional outcomes are important for oncology patients undergoing lower extremity reconstruction. The objective of the current study was to describe patient reported function after surgery and identify predictors of postoperative function in musculoskeletal oncology patients undergoing lower extremity endoprosthetic reconstruction. Methods: We performed a cohort study with functional outcome data from the recently completed Prophylactic Antibiotic Regimens in Tumor Surgery (PARITY) trial. We utilized the 100-point Toronto Extremity Salvage Score (TESS), which was administered pre-operatively and at 3, 6 and 12 months post-operatively. Higher scores indicate better physical functioning, and the minimally important difference is 11 points. We calculated mean functional scores at each timepoint after surgery and developed a logistic regression model to explore predictors of failure to achieve excellent post-operative function (TESS ≥ 80) at 1 year after surgery. Results: The 555 patients included in our cohort showed important functional improvement from pre-surgery to 1 year post-surgery (mean difference 14.9 points, 95%CI 12.2 to 17.6; p < 0.001) and 64% achieved excellent post-operative function. Our adjusted regression model found that poor (TESS 0–39) pre-operative function (odds ratio [OR] 3.3, 95%CI 1.6 to 6.6); absolute risk [AR] 24%, 95%CI 8% to 41.2%), older age (OR per 10-year increase from age 12, 1.32, 95%CI 1.17, 1.49; AR 4.5%, 95%CI 2.4% to 6.6%), and patients undergoing reconstruction for soft-tissue sarcomas (OR 2.3, 95%CI 1.03 to 5.01; AR 15.3%, 95%CI 0.4% to 34.4%), were associated with higher odds of failing to achieve an excellent functional outcome at 1-year follow-up. Patients undergoing reconstruction for giant cell tumors were more likely to achieve an excellent functional outcome post-operatively (OR 0.40, 95%CI 0.17 to 0.95; AR −9.9%, 95%CI −14.4% to −0.7%). Conclusions: The majority of patients with tumors of the lower extremity undergoing endoprosthetic reconstruction achieved excellent function at 1 year after surgery. Older age, poor pre-operative function, and endoprosthetic reconstruction for soft tissue sarcomas were associated with worse outcomes; reconstruction for giant cell tumors was associated with better post-operative function. Level of Evidence: Therapeutic Level IV.

Venous thromboembolism in musculoskeletal oncology surgery.

Venous thromboembolism (VTE), including both deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major complication of musculoskeletal surgery in general, and the risk is heightened in musculoskeletal oncology surgery. Despite the well-known association between cancer and VTE, the mechanism promoting this pathology is not entirely well understood. It is estimated that nearly all cancer patients will experience from some form of VTE, whether or not clinically relevant, during the course of their disease. Nonetheless, numerous studies have analyzed the occurrence and prevention of VTE in patients with cardiovascular disease or suffering trauma, but very few have specifically examined the safety or efficacy of preventing VTE in cancer patients with metastatic skeletal disease. This review will examine the various types of prophylactic treatment, timing of administration, risk stratification for determining the appropriate course of anticoagulation (AC), and discuss current views on chemical prophylaxes relativity to wound complications and excessive bleeding in orthopedic oncology patients. Overall, careful choice of anticoagulant and timing of administration must be made in order to avoid bleeding complications. A risk stratification system to determine which chemical prophylaxis to administered could be beneficial in both reducing the occurrence of VTE and decreasing associated wound complications or mortality. Further study should be conducted to tailor chemical prophylaxes recommendations to this largely affected population and effectively reduce the occurrence of VTE.