Bone Mass Changes Following Percutaneous Radiofrequency Ablation, Osteoplasty, Reinforcement, and Internal Fixation of Periacetabular Osteolytic Metastases.

BACKGROUND: The success of orthopedic interventions for periacetabular osteolytic metastases depends on the progression or regression of cancer-induced bone loss. PURPOSE: To characterize relative bone mass changes following percutaneous radiofrequency ablation, osteoplasty, cement reinforcement, and internal screw fixation (AORIF). METHODS: Of 70 patients who underwent AORIF at a single institution, 21 patients (22 periacetabular sites; average follow-up of 18.5 ± 12.3 months) had high-resolution pelvic bone CT scans, with at least one scan within 3 months following their operation (baseline) and a comparative scan at least 6 months post-operatively. In total, 73 CT scans were measured for bone mass changes using Hounsfield Units (HU). A region of interest was defined for the periacetabular area in the coronal, axial, and sagittal reformation planes for all CT scans. For 6-month and 1-year scans, the coronal and sagittal HU were combined to create a weight-bearing HU (wbHU). Three-dimensional volumetric analysis was performed on the baseline and longest available CT scans. Cohort survival was compared to predicted PathFx 3.0 survival. RESULTS: HU increased from baseline post-operative (1.2 ± 1.1 months) to most recent follow-up (20.2 ± 12.1 months) on coronal (124.0 ± 112.3), axial (140.3 ± 153.0), and sagittal (151.9 ± 162.4), p < 0.05. Grayscale volumetric measurements increased by 173.4 ± 166.4 (p < 0.05). AORIF median survival was 27.7 months (6.0 months PathFx3.0 predicted; p < 0.05). At 12 months, patients with >10% increase in wbHU demonstrated superior median survival of 36.5 months (vs. 26.4 months, p < 0.05). CONCLUSION: Percutaneous stabilization leads to improvements in bone mass and may allow for delays in extensive open reconstruction procedures.

Comparison of Percutaneous Interventional Ablation-Osteoplasty-Reinforcement-Internal Fixation (AORIF), Long Intramedullary Nailing, and Hemiarthroplasty for the Treatment of Focal Metastatic Osteolytic Lesions in the Femoral Head and Neck.

PURPOSE: Osteolytic metastatic lesions in the femoral head and neck are traditionally treated with intramedullary long nailing (IM) or hemiarthroplasty (HA). Recovery, surgical complications, and medical co-morbidities delay oncologic care. This study sought to elucidate the comparative efficacy of percutaneous ablation-osteoplasty-reinforcement-internal fixation (AORIF), IM, and HA in stabilizing osteolytic lesions in the femoral head and neck. METHODS: A retrospective study of 67 patients who underwent IM, AORIF, or HA for osteolytic femoral head and neck lesions was performed. Primary outcome was assessed using a combined pain and ambulatory score (Range 1-10: 1 = bedbound, 10 = normal ambulation) at first follow-up (~ 2 weeks). Surgical complications associated with each treatment were compared. RESULTS: Sixty-seven patients (mean age, 65 ± 13, 36 men and 31 women) underwent IM (40), AORIF (19), and HA (8) with a mean follow-up of 9 ± 11 months. Two patients in the IM group (5%), three in the AORIF group (16%), and none in the HA (0%) group required revision procedures. AORIF demonstrated superior early improvement in combined pain and ambulatory function scores by 3.0 points [IQR = 2.0] (IM p = 0.0008, HA p = 0.0190). Odds of post-operative complications was 10.3 times higher in HA than IM (95% confidence interval 1.8 to 60.3). Future revision procedures were not found to be statistically significant between AORIF and IM (p = 0.234). CONCLUSIONS: A minimally invasive interventional skeletal procedure for focal femoral head and neck osteolytic lesions may serve as an effective alternative treatment to traditional surgical approaches, conferring a shorter recovery time and fewer medical complications.

Percutaneous Ablation, Osteoplasty, Reinforcement, and Internal Fixation for Pain and Ambulatory Function in Periacetabular Osteolytic Malignancies.

Background Osteolytic neoplasms to periacetabular bone frequently cause pain and fractures. Immediate recovery is integral to lifesaving ambulatory oncologic care and maintaining quality of life. Yet, open acetabular reconstructive surgeries are associated with numerous complications that delay cancer treatments. Purpose To determine the effectiveness for short- and long-term pain and ambulatory function following percutaneous ablation, osteoplasty, reinforcement, and internal fixation (AORIF) for periacetabular osteolytic neoplasm. Materials and Methods This retrospective observational study evaluated clinical data from 50 patients (mean age, 65 years ± 14 [SD]; 25 men, 25 women) with osteolytic periacetabular metastases or myeloma. The primary outcome of combined pain and ambulatory function index score (range, 1 [bedbound] through 10 [normal ambulation]) was assessed before and after AORIF at 2 weeks and then every 3 months up to 40 months (overall median follow-up, 11 months [IQR, 4-14 months]). Secondary outcomes included Eastern Cooperative Oncology Group (ECOG) score, infection, transfusion, 30-day readmission, mortality, and conversion hip arthroplasty. Serial radiographs and CT images were obtained to assess the hip joint integrity. The paired t test or Wilcoxon signed-rank test and Kaplan-Meier analysis were used to analyze data. Results Mean combined pain and ambulatory function index scores improved from 4.5 ± 2.4 to 7.8 ± 2.1 (P < .001) and median ECOG scores from 3 (IQR, 2-4) to 1 (IQR, 1-2) (P < .001) at the first 2 weeks after AORIF. Of 22 nonambulatory patients, 19 became ambulatory on their first post-AORIF visit. Pain and functional improvement were retained beyond 1 year, up to 40 months after AORIF in surviving patients. No hardware failures, surgical site infections, readmissions, or delays in care were identified following AORIF. Of 12 patients with protrusio acetabuli, one patient required a conversion hemiarthroplasty at 24 months. Conclusion The ablation, osteoplasty, reinforcement, and internal fixation, or AORIF, technique was effective for short- and long-term improvement of pain and ambulatory function in patients with periacetabular osteolytic neoplasm. © RSNA, 2023.

Rare Presentation of Rosai-Dorfman Disease in Soft Tissue: Diagnostic Findings and Surgical Treatment.

Introduction and Importance. Rosai-Dorfman disease (RDD) is a rare, benign type II histiocytosis characterized by the infiltration of S100+ histiocytes and emperipolesis. The disease may present in the lymph nodes (nodal RDD), in extranodal sites, or in both nodal and extranodal sites. Among those patients who present exclusively in extranodal sites, only a minority of cases present in the soft tissue. Case Presentation. An 18-year-old female presented to orthopedic oncology clinic with a chief complaint of a mass located in her lower back. The patient underwent excision of the lumbosacral mass. Pathologic review demonstrated emperipolesis of lymphocytes and plasma cells within enlarged, eosinophilic histiocytes in a background of lymphoplasmacytic infiltration and collagenous stroma. Immunohistochemical staining demonstrated S100+ and CD163+ histiocytes, consistent with diagnosis of soft tissue RDD. Clinical Discussion. Histologically, RDD is generally characterized by emperipolesis-the presence of intact lymphocytes within the histiocyte cytoplasm-and a mixed infiltrate of S100+ histiocytes, mononuclear cells, plasma cells, and lymphocytes. Although soft tissue RDD may histologically resemble nodal RDD, soft tissue RDD also demonstrates some notable histologic differences including the lack of nodal architecture, the presence of increased fibrosis and collagen deposition, and generally fewer RDD cells. Conclusion. This case presentation demonstrates one few reports of isolated soft tissue RDD within the lumbosacral region without associated lymphadenopathy or skin changes and highlights the heterogeneity that still exists in the treatment paradigm of extranodal RDD.

Surgical Excision of a Giant Schwannoma of the Hand: A Case Report.

CASE: We report a 78-year-old man who underwent excision of a 13-year-old benign schwannoma originating from the terminal motor branch of the ulnar nerve. The mass measured 13 cm in diameter on presentation and was successfully excised, preserving a functional hand. At 4-year follow-up, the patient was asymptomatic with intact motor and sensory function and no signs of recurrence. To the best of our knowledge, this is the largest schwannoma of the hand to be reported in the literature. CONCLUSIONS: Large schwannomas of the hand can successfully be excised with no postoperative complications.

Retroperitoneal Approach for Excision of Wear-Debris Pseudotumor: A Case Report.

CASE: Pelvic pseudotumors may occur as a reaction to wear-debris after hip arthroplasty and are rarely treated with surgery. We describe an instance in which a pelvic pseudotumor along the iliopsoas muscle tendon sheath was debulked using a retroperitoneal approach in a patient presenting for treatment of a prosthetic hip infection. The patient recovered uneventfully and was ambulatory with a new hip prosthesis at 3 months after procedure. CONCLUSIONS: Retroperitoneal exposure provided safe, excellent exposure to a wear-debris pelvic pseudotumor in this case.

Bone Scans Have Little Utility in the Evaluation of Well-Differentiated Cartilaginous Lesions of the Humerus.

In the humerus, pain is a poor guide for differentiating between benign enchondromas and malignant well-differentiated chondrosarcomas. Radionuclide bone scans often are used, and chondrosarcomas reliably show increased uptake. However, it remains to be seen whether enchondromas consistently have negative findings on bone scans, which would provide reliable differentiation from malignant lesions. Imaging and medical records were reviewed for patients who underwent radionuclide bone scans for enchondroma of the humerus at one academic medical center over a period of 7 years. Bivariate logistic regression was used to determine the association of bone scan results with the finding of endosteal scalloping on radiographs and magnetic resonance imaging (MRI) scans. During initial evaluation, 25 patients who had enchondroma of the humerus underwent radionuclide bone scans. No patients showed progression of lesions during an average follow-up of 69 weeks. On bone scan, 18 (72%) had significantly positive findings, 5 (20%) had mildly positive findings, and 2 (8%) had negative findings. Of the 22 patients who underwent MRI scans, 4 showed endosteal scalloping and none showed aggressive features. No statistically significant association was seen between significantly positive (P=.299) or mildly positive findings on bone scans (P=.810) and the finding of endosteal scalloping on radiographs or MRI scans. Enchondromas rarely showed negative findings on bone scans, and bone scan findings did not correlate with the findings on radiographs or MRI scans. The diagnosis of enchondroma can be made based on clinical and radiographic findings, and the added utility of bone scans does not justify their regular use. [Orthopedics. 2020;43(6):e498-e502.].

Synovial Myxoma: Found in Canines, Rabbits, and Now Humans Too?: A Case Report.

CASE: A 63 year-old woman presented with a multiple-year history of right knee pain and effusions and pain refractory to numerous knee aspirations and an arthroscopic synovectomy. The patient underwent a 2-incision synovectomy and intralesional resection. A pathologic review of the specimens revealed an infiltrative tumor of basophilic, cluster of differentiation 68-positive synovial cells embedded within a myxoid stroma with low proliferative activity, most consistent with a synovial myxoma. CONCLUSIONS: This case report of a synovial myxoma-a benign, slow growing but locally aggressive mass that is most commonly found in canines-indicates that the lesion may occasionally occur in humans.

Minimally Invasive Image-Guided Ablation, Osteoplasty, Reinforcement, and Internal Fixation (AORIF) for Osteolytic Lesions in the Pelvis and Periarticular Regions of Weight-Bearing Bones.

PURPOSE: To assess early outcome, safety, and complications of an alternative to open surgical treatments of osteolytic lesions in periarticular load-bearing bones. MATERIALS AND METHODS: A single-center, prospective clinical cohort study of 26 lesions in 23 consecutive patients with painful osteolytic skeletal lesions was performed. Patients were followed for an average of 7 mo (1-18 mo). Lesions were targeted from the most intact bone via minimally invasive percutaneous approach for stable anchorage of internal fixation screws using fluoroscopic guidance. Cannulated screws served as universal portals for ablation, balloon osteoplasty, and delivery of bone cement in addition to internal fixation for cement anchoring and prophylactic stabilization of uninvolved bone. RESULTS: There were 19 osteolytic lesions in the pelvis, 4 in the proximal femur, 2 in the proximal tibia, and 1 in the calcaneus. All defects were associated with severe pain or fractures. There were no conversions to open surgery and no infection or bleeding requiring transfusion, embolization, or additional procedures. There was significant improvement in visual analogue scale (VAS) pain score from 8.32 ± 1.70 to 2.36 ± 2.23, combined pain and functional ambulation score from 4.48 ± 2.84 to 7.28 ± 2.76, and Musculoskeletal Tumor Society score from 45% to 68% (P < .05). CONCLUSIONS: Ablation, osteoplasty, reinforcement, and internal fixation is a safe and effective minimally invasive percutaneous image-guided treatment option for functional improvement or palliation of painful osteolytic lesions in the pelvis and periarticular loadbearing bones.

Predictors of Lymph Node Involvement by Soft Tissue Sarcoma of the Trunk and Extremity: An Analysis of the National Cancer Database.

Background and Objectives Lymph node metastases (LNM) in soft tissue sarcoma (STS) of the trunk and extremity are rare but are associated with worse survival. Established risk factors for LNM in this group are based on small institutional retrospective reviews. This study identifies the risk factors associated with LNM in otherwise non-metastatic trunk/extremity STS patients using the National Cancer Database (NCDB) and sought out to delineate a high-risk group that may be considered for pathologic nodal evaluation. Methods The files of 10,731 patients with STS of the trunk/extremity without distant metastasis from 2004 - 2015 were evaluated. Exclusion criteria included neoadjuvant therapy and a lack of pathologic nodal evaluation. Univariate and multivariable logistic regression models were performed to evaluate variables associated with LNM. Results Of the total of 10,731 patients, 223 (2.1%) had LNM. On multivariable analysis, LNM was associated with Grade 3 tumors (odds ratio (OR) 15.6, 95% confidence interval (CI) 6.36 - 38.04, p < 0.001) and clear cell/angiosarcoma/rhabdomyosarcoma/epithelioid (CARE) histology (OR 4.72, 95% CI 3.35 - 6.66, p < 0.001), lymphovascular invasion (LVI) (OR 5.86, 95% CI 3.33 - 10.31, p < 0.001, and bone invasion (BI) (OR 2.73, 95% CI 1.32 - 5.61, p = 0.006). Patients with Grade 3 CARE tumors (n = 402) had an 11.9% risk of LNM vs. 1.7% of adults without all these characteristics (p < 0.001). Patients with Grade 3 CARE tumors and either LVI or BI (n = 36) had a 33.3% risk of LNM. Conclusions High-grade and CARE histology are associated with LNM in STS. Adult patients with both features have an overall 11.9% risk of LNM and may be considered for pathologic LN assessment, particularly with the presence of LVI or BI.

Bone Marrow Adiposity: Basic and Clinical Implications.

The presence of adipocytes in mammalian bone marrow (BM) has been recognized histologically for decades, yet, until recently, these cells have received little attention from the research community. Advancements in mouse transgenics and imaging methods, particularly in the last 10 years, have permitted more detailed examinations of marrow adipocytes than ever before and yielded data that show these cells are critical regulators of the BM microenvironment and whole-body metabolism. Indeed, marrow adipocytes are anatomically and functionally separate from brown, beige, and classic white adipocytes. Thus, areas of BM space populated by adipocytes can be considered distinct fat depots and are collectively referred to as marrow adipose tissue (MAT) in this review. In the proceeding text, we focus on the developmental origin and physiologic functions of MAT. We also discuss the signals that cause the accumulation and loss of marrow adipocytes and the ability of these cells to regulate other cell lineages in the BM. Last, we consider roles for MAT in human physiology and disease.

Femoral and Tibial Reconstruction for Skeletal Metastases and Pathologic Fractures.

Skeletal metastases of the femur and tibia leading to pathologic fractures or large skeletal defects can be managed with surgical reconstruction, resulting in improved patient outcomes and functionality. The indications for femoral and tibial reconstruction are dependent on several factors, including goals of management, age, comorbidities, site and extent of the lesion, soft-tissue involvement, and history of radiation or other systemic therapy. The goal of reconstruction of large bone defects is to restore anatomy and function while minimizing the risk of complications, implant failure, and subsequent revision procedure. Common reconstructive options include fixation with plates and screws, intramedullary nails, and endoprosthesis implantation.

What Is the Adverse Event Profile After Prophylactic Treatment of Femoral Shaft or Distal Femur Metastases?

BACKGROUND: Prophylactic surgical treatment of the femur is commonly offered to patients with metastatic disease who have a high risk of impending pathologic fracture. Prophylactic fixation is associated with improved functional outcomes in appropriate patients selected based on established criteria, but the perioperative complication profile has received little attention. Given the substantial comorbidity in this population, it is important to characterize surgical risks for surgeons and patients to improve treatment decisions. QUESTIONS/PURPOSES: (1) What is the incidence of postoperative adverse events after prophylactic surgical stabilization of metastatic lesions of the femoral shaft or distal femur? (2) How does this complication profile compare with stabilization of pathologic fractures adjusted for differences in patient demographics and comorbidity? METHODS: We performed a retrospective study using the National Surgical Quality Improvement Program (NSQIP) database. We identified patients undergoing prophylactic treatment of the femoral shaft or distal femur by Current Procedural Terminology (CPT) codes. Patients undergoing treatment of a pathologic fracture were identified by CPT code for femur fracture fixation as well as an International Classification of Diseases code indicating neoplasm or pathologic fracture. We tracked adverse events, operative time, blood transfusion, hospital length of stay, and discharge to a facility within 30 days postoperatively. There were 332 patients included in the prophylactic treatment group and 288 patients in the pathologic fracture group. Patients in the prophylactic treatment group presented with greater body mass index (BMI), whereas the pathologic fracture group presented with a greater incidence of disseminated cancer. The odds of experiencing adverse events were initially compared between the two groups using bivariate logistic regression and then using multivariate regression controlling for age, sex, BMI, and American Society of Anesthesiologists (ASA) class and disseminated cancer causing marked physiological compromise per NSQIP guidelines. RESULTS: With multivariate analysis controlling for age, sex, BMI, and ASA class, patients with pathologic fracture were more likely to experience any adverse event (odds ratio [OR], 1.53; 95% confidence interval [CI], 1.03-2.29; p = 0.036), major adverse events (OR, 1.61; 95% CI, 1.01-2.55; p = 0.043), death (OR, 1.90; 95% CI, 1.07-3.38; p = 0.030), blood transfusion (OR, 1.57; 95% CI, 1.08-2.27; p = 0.017), and hospital stay ≥ 9 days (OR, 1.51; 95% CI, 1.05-2.19; p = 0.028) compared with patients undergoing prophylactic treatment. However, when additionally controlling for disseminated cancer, the only difference was that patients with pathologic fractures were more likely to receive a blood transfusion than were patients undergoing prophylactic fixation (OR, 1.61; 95% CI, 1.12-2.36; p = 0.011). CONCLUSIONS: After controlling for differences in patient characteristics, prophylactic treatment of femoral metastases was associated with a decreased likelihood of blood transfusion and no differences in terms of the frequency of other adverse events. In the context of prior studies supporting the mechanical and functional outcomes of prophylactic treatment, the findings of this cohort suggest that the current guidelines have achieved a reasonable balance of morbidity in patients with femoral lesions and further support the current role of prophylactic treatment of impending femur fractures in appropriately selected patients. LEVEL OF EVIDENCE: Level III, therapeutic study.

Molecular Targeted Therapy Approach to Musculoskeletal Tumors.

The future of cancer treatment is promising. Although marred by years of plateau in outcomes, new avenues have been identified that are poised to change how we treat cancer. Molecular targeted therapy or targeted therapy is one of these methods. Molecular targeted therapy involves identifying specific pathways or markers that allow cancer cells to flourish. Once identified, specific molecules can be used to block proliferative pathways, thereby negatively impacting tumor growth. Targeting specific pathways that prolong the survival of the cancer cell can lead to a decreased cancer burden, and improved patient outcomes. This article reviews the tenets of molecular targeted therapy, common pathways, target acquisition for drug development, and the pathways that have been elucidated in musculoskeletal tumors.

Bone marrow adipocytes.

Adipocytes were identified in human bone marrow more than a century ago, yet until recently little has been known about their origin, development, function or interactions with other cells in the bone marrow. Little functional significance has been attributed to these cells, a paradigm that still persists today. However, we now know that marrow adipose tissue increases with age and in response to a variety of physiologic induction signals. Bone marrow adipocytes have recently been shown to influence other cell populations within the marrow and can affect whole body metabolism by the secretion of a defined set of adipokines. Recent research shows that marrow adipocytes are distinct from white, brown and beige adipocytes, indicating that the bone marrow is a distinct adipose depot. This review will highlight recent data regarding these areas and the interactions of marrow adipose tissue (MAT) with cells within and outside of the bone marrow.

NCCN Guidelines Insights: Bone Cancer, Version 2.2017.

The NCCN Guidelines for Bone Cancer provide interdisciplinary recommendations for treating chordoma, chondrosarcoma, giant cell tumor of bone, Ewing sarcoma, and osteosarcoma. These NCCN Guidelines Insights summarize the NCCN Bone Cancer Panel's guideline recommendations for treating Ewing sarcoma. The data underlying these treatment recommendations are also discussed.

Leiomyoma of the Foot and Ankle: A Case Series.

Leiomyoma is a benign soft-tissue tumor that can arise in any soft tissue; however, in the extremities, it is usually a subcutaneous mass. Masses in the foot and ankle in general are rare, and few reports in the literature describe leiomyoma in this region of the body. We present a series of 8 cases of leiomyoma of the foot and ankle, 4 of which are subclassified as angioleiomyomas. The characteristic patient presentation, imaging, and histological findings are presented here to increase awareness of this soft-tissue mass in the foot and ankle. LEVELS OF EVIDENCE: Level V.

Bilateral atypical femur fractures without bisphosphonate exposure.

Atypical femur fractures have common radiographic features that set them apart from more typical higher-energy subtrochanteric femur fractures. They are noncomminuted, transverse fractures with medial spiking of the femoral cortex and increased lateral cortical thickness. These fractures have been associated in the literature with the use of bisphosphonate medications. This case describes bilateral atypical femur fractures in a patient with a medical history devoid of bisphosphonate use. We present his history, co-morbidities, and subsequent treatment. From this case, we call attention to bisphosphonate use as not the only cause of subtrochanteric femur fractures with atypical features and highlight that some patients may sustain these injuries even bilaterally without use of the medications. In addition, it is important to identify this fracture type and obtain imaging of the contralateral femur to facilitate prophylactic treatment if needed.

Case of a Missed Giant Cell Tumor of Bone: An Opportunity to Observe its Natural History Disease.

Giant cell tumor of bone (GCT) is a benign neoplasm that most commonly presents with pain and is rarely diagnosed as an incidental finding. We present the report of a young woman whose pre-operative MRI was only noted to have a tear of the anterior cruciate ligament (ACL). Subsequently, the patient underwent anACL reconstruction. A second MRI, performed four years later, demonstrated an enlarged mass in the same location. A retrospective evaluation of the initial MRI revealed an eccentric metaphyseal lesion. Histology obtained from the lesion demonstrated a giant cell tumor of bone. We present the case of an asymptomatic GCT discovered retrospectively as an incidental finding and reevaluated four years later. 'Ihis case serves as a reminder of the importance for the critical review of routine preoperative imaging and also offers a unique perspective on the natural history of giant cell tumor of bone.

Intraoperative radiofrequency ablation for osteoid osteoma.

Percutaneous radiofrequency ablation (RFA) has been increasingly used in the treatment of osteoid osteoma (OO), as this method has provided satisfactory results with minimal morbidity. RFA traditionally has been performed by radiologists under computed tomography (CT) guidance. Advances in intraoperative imaging techniques now allow orthopedic oncologists to perform image-guided RFA in the operating room. We conducted a study to evaluate the efficacy of a novel technique that uses intraoperative CT-guided RFA to treat OO. We reviewed 28 consecutive cases of OO treated with intraoperative RFA by a single surgeon between September 2004 and December 2008. Primary or secondary success was defined as complete pain relief without evidence of recurrence after the first or second procedure, respectively. Failure was defined as the continued presence of symptoms combined with radiographic evidence of recurrence. Primary success rate was 92.8%. Two patients had a recurrence and underwent a successful second RFA. Our success rates are similar to those in the radiology literature. Further studies are needed to validate the efficacy of this novel technique.