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A 50-year-old male presented with left hallux pain and swelling that was treated for infection. Initial imaging studies were inconclusive, but further evaluation led to a diagnosis of high-grade primary osteosarcoma. Despite surgery and chemotherapy, the disease progressed rapidly, and 7 months after toe amputation multiple lung metastases were discovered. The patient died 15 months after diagnosis. Foot osteosarcomas are extremely rare malignant neoplasms that are often misdiagnosed, resulting in delayed or inappropriate treatment. It is imperative to maintain a high index of suspicion of any destructive bone lesions in the foot, regardless of size and symptom severity.
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Metastatic disease of the periacetabular region is a common problem in orthopaedic oncology, associated with severe pain, decreased mobility, and substantial decline of the quality of life. Conservative management includes optimisation of pain management, activity modification, and radiation therapy. However, patients with destructive lesions affecting the weight-bearing portion of the acetabulum often require reconstructive surgery to decrease pain and restore mobility. The goal of surgery is to provide an immediately stable and durable construct, allowing immediate postoperative weight-bearing and maintaining functional independence for the remaining lifetime of the patient. A variety of surgical techniques have been reported, most of which are based upon cemented total hip arthroplasty, but also include porous tantalum implants and percutaneous cementoplasty. This review discusses the various reconstructive concepts and options, including their respective indications and outcome. A reconstructive algorithm incorporating different techniques and strategies based upon location and quality of remaining bone is also presented.

Aims/UNASSIGNED:Our objective was to determine if preoperative patient-reported assessments are associated with survival after surgery for stabilization of skeletal metastases. Patients and Methods/UNASSIGNED:All patients with metastatic cancer to bone and indications for skeletal stabilization surgery were approached to participate in a prospective cohort study at a tertiary care center from 2012 to 2017. Of the 208 patients who were eligible, 195 (94%) completed the 36-item Short Form Health Survey (SF-36) preoperatively and underwent surgical treatment of skeletal metastases with complete or impending fractures; the sample encompassed a range of cancer diagnoses and included cases of both internal fixation and endoprosthetic replacement. Cox proportional hazards models were used to identify associations between SF-36 scores and survival. Results/UNASSIGNED: < 0.001). Conclusions/UNASSIGNED:Patients' preoperative assessments of their health status are associated with their survival after surgery for skeletal metastases. Patient-reported assessments have the potential to contribute unique information to models that estimate patient survival, as part of efforts to provide optimal, individualized care and make informed decisions about the type and magnitude of surgery for metastatic bone disease that will last the patient's lifetime.

The surgical management of acetabular and pelvic lesions due to metastatic bone disease is complex in nature. These patients are typically in a frail state, having severe pain, limited mobility, and impaired wound healing. This causes a potential for complications, a high concern for the surgeon. Compounding these issues is limited life span for these patients given the advancement of the disease. Considerations for patients undergoing surgical treatment are achievement of significant pain relief and restoration of ambulation, all while having minimal complications during the postoperative period. Management may also include nonsurgical and interventional methods. A multidisciplinary approach is required for the successful treatment of these patients. Although there have been various surgical methods described, there is still no standardized modality that has been noted. These lesions often require complex decision making, imaging, and surgical reconstruction.

Soft tissue sarcoma (STS) of the extremities is typically treated with limb-sparing surgery and radiation therapy; with this treatment approach, high local control rates can be achieved. However, postradiation bone fractures, fractures occurring in the prior radiation field with minimal or no trauma, are a serious late complication that occurs in 2-22% of patients who receive surgery and radiation for STS. Multiple risk factors for sustaining a postradiation fracture exist, including high radiation dose, female sex, periosteal stripping, older age, femur location, and chemotherapy administration. The treatment of these pathological fractures can be difficult, with complications including delayed union, nonunion, and infection posing particular challenges. Here, we review the mechanisms, risk factors, and treatment challenges associated with postradiation fractures in STS patients.

Limb-salvage surgery for pelvic sarcomas remains one of the most challenging surgical procedures for musculoskeletal oncologists. In the past several decades, various surgical techniques have been developed for periacetabular reconstruction following pelvic tumor resection. These methods include endoprosthetic reconstruction, allograft or autograft reconstruction, arthrodesis, and hip transposition. Each of these procedures has its own advantages and disadvantages, and there is no consensus or gold standard for periacetabular reconstruction. Consequently, this review provides an overview of the clinical outcomes for each of these reconstructive options following pelvic tumor resections. Overall, high complication rates are associated with the use of massive implants/grafts, and deep infection is generally the most common cause of reconstruction failure. Functional outcomes decline with the occurrence of severe complications. Further efforts to avoid complications using innovative techniques, such as antibiotic-laden devices, computer navigation, custom cutting jigs, and reduced use of implants/grafts, are crucial to improve outcomes, especially in patients at a high risk of complications.

Computer-assisted navigation and robotic surgery have gained popularity in the treatment of pelvic bone malignancies, given the complexity of the bony pelvis, the proximity of numerous vital structures, and the historical challenges of pelvic bone tumor surgery. Initial interest was on enhancing the accuracy in sarcoma resection by improving the quality of surgical margins and decreasing the incidence of local recurrences. Several studies have shown an association between intraoperative navigation and increased incidence of negative margin bone resection, but long-term outcomes of navigation in pelvic bone tumor resection have yet to be established. Historically, mechanical stabilization of pelvic bone metastases has been limited to Harrington-type total hip arthroplasty for disabling periacetabular disease, but more recently, computer-assisted surgery has been employed for minimally invasive percutaneous fixation and stabilization; although still in its incipient stages, this procedure is potentially appealing for treating patients with bone metastases to the pelvis. The authors review the literature on navigation for the treatment of primary and metastatic tumors of the pelvic bone and discuss the best practices and limitations of these techniques.

BACKGROUND:Compliant compression fixation was developed to promote permanent bone-prosthesis osteointegration while preserving bone stock in patients needing endoprosthetic reconstructions. This has demonstrated durability in the distal femur, with reliable cortical hypertrophy adjacent to the implant. However, the extent of bone formation and prosthetic survivorship of proximal femoral replacements with compliant compression fixation has not been established. QUESTIONS/PURPOSES:(1) How much bone formation occurs across the compression segment in patients treated with a proximal femoral replacement implant using compliant compression fixation? (2) What were the Musculoskeletal Tumor Society (MSTS) scores at minimum 24-month follow-up of patients who received this reconstruction? (3) What is the implant survivorship free from implant removal or revision for any reason at final follow-up? METHODS:From 2006 to 2018, we performed 213 proximal femoral replacements in patients with oncologic conditions of the proximal femur where the trochanters could not be preserved. Of these, 6% (12 of 213) were performed with an implant that used compliant compression fixation. We used this device in primary oncologic reconstructions in patients younger than 65 years of age without metastases who had nonirradiated bone with the requisite ≥ 2.5 mm of cortical thickness in the hope that it would provide more durable fixation and bone stock preservation than conventional reconstructions. All patients were followed for longer than 2 years except one who died in that interval. Median (range) follow-up was 6 years (2 to 10 years). Seven patients received diagnosis-specific chemotherapy in a consistent manner based on Children's Oncology Group chemotherapy protocols. Using the NIH-developed ImageJ open-access software, we measured the area of bone under compression on 3-, 6-, 9-, 12-, 18-, and 24-month radiographs and the length of the traction bar potential-compression distance, reconciling independent measures from two investigators using the identical method as published for the distal femur with compression fixation. The duration of prosthesis retention was evaluated using a competing risk analysis for the 11 surviving patients. RESULTS:Bone hypertrophy in the compression segment was scant. At the final analysis, cortical bone formation was a median (range) of 4 (-7 to 14) above baseline. The median (range) MSTS score was 27 (19 to 30). One implant failed after trauma, and the patient underwent revision of the implant. CONCLUSION:Despite scant bone formation across the compression segment and drastically less formation than reported for distal femoral replacements, compliant compression fixation of the proximal femur demonstrated good survivorship in patients 65 years or younger with localized sarcoma and nonirradiated, adequate bone stock in this small, retrospective series. Patients achieved good functional outcomes at final follow-up. The potential benefit of this reconstruction method should be weighed against the initial period of limited weightbearing and the life expectancy of the patient. LEVEL OF EVIDENCE:Level IV, cohort study.

Distal femoral endoprosthetic replacement has been successfully used to reconstruct distal femoral defects after tumor resection for over four decades. Despite continued advances, aseptic loosening continues to be the most common failure mode after infection. Debate still exists about a variety of design features and the optimal fixation method remains controversial. To date, no large-scale study or meta-analysis has demonstrated the superiority of one fixation technique over another. While the classic dichotomy of cemented versus cementless stems is well-known, the contemporary surgeon needs to fully understand the optimal clinical setting for each type of fixation technique and additional strategies to maximize implant stability. In clinical practice, the choice of fixation must be tailored to the individual patient. The surgeon must consider whether the operation is being performed for primary sarcoma or metastatic carcinoma, the presence of distant metastases, age, comorbidities, and whether radiotherapy has been previously given or will be required at the site of fixation. The best strategy for each patient optimizes tumor control and appropriately weighs risks of fixation failure versus the expected patient survival. This review will explore cemented and uncemented distal femoral replacement and highlight modern concepts to optimize each technique.