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Background Management of impending pathologic femoral neck fractures includes internal fixation, arthroplasty and megaprostheses. The study aim was to determine the augmentative effect of cement injection for minimally invasive treatment of femoral neck lesions. Methods Twenty-seven cadaveric femora received a simulated osteolytic lesion previously shown to decrease the femur's failure load by 50%. Specimens were allocated to three groups of nine and loaded to failure in simulated single-leg stance: (1) percutaneous cementation + internal fixation (PCIF); (2) percutaneous cementation (PC); and (3) internal fixation (IF). Lesion-only and augmented finite element models were virtually loaded and stresses were queried adjacent to the lesion. Findings PCIF resulted in the largest failure load though the increase was not significantly greater than the PC or IF groups. Inspection of the PC and PCIF specimens indicated that the generation of a cement column that spanned the superior and inferior cortices of the femoral neck increased failure loads significantly. Finite element analysis indicated that IF and PCIF constructs decreased the stress adjacent to the lesion to intact femur levels. Cementation without superior-to-inferior femoral neck cortical contact did not restore proximal femoral stress toward the intact condition. Interpretation Internal fixation alone and internal fixation with or without cementation produce similar levels of mechanical augmentation in femora containing a high-risk lesion of impending fracture. A cement injection technique that produces a cement column contacting the superior and inferior femoral neck cortices confers the highest degree of biomechanical stability, should percutaneous cementation alone be performed.

Background. Little is known about how cumulative chemotherapy delivery influences the poorer outcome observed in young adult (YA, 18–40 years) versus pediatric (Methods. We reviewed 111 cases of high-grade osteosarcoma at Moffitt Cancer Center between 1988 and 2012. Presentation factors, therapies, and survival were compared between YA and pediatric cohorts.Results. The cohorts were equivalent with respect to metastatic status, gender, tumor size, tumor site, and histological subtype. We found that the YA patients tended to have poorer histologic response to neoadjuvant chemotherapy measured by necrosis with 55% and 35% of pediatric versus YA patients responding favorably (P=0.06). Only 39% of YA patients achieved the typical pediatric dose of methotrexate, doxorubicin, and cisplatin. These patients had a 3-year EFS of 76% (CI 53–100%) versus 47% (CI 26–69%;P=0.09) in those who received less chemotherapy.Conclusion. Age continues to be a prognostic factor in osteosarcoma. Our study suggests that presentation factors are not associated with prognosis, while poorer response to chemotherapy and lower cumulative dose of chemotherapy delivered to YA patients may contribute to poorer outcomes.