Liposarcoma of the thigh with mixed calcification and ossification.

Liposarcoma is one of the most common soft-tissue sarcomas. Calcification and ossification can occur in liposarcoma; however, the presence of both ossification and calcification is a very rare entity. We present a case of a partially calcified and ossified dedifferentiated liposarcoma of the thigh in a 76-year-old woman, which contained heterologous elements of chondrosarcoma and rhabdomyosarcoma.

Testing of double-stranded allografts used in ACL reconstruction.

We used bovine tibiae and two-stranded human anterior tibialis tendon grafts to compare biomechanical properties of two tibial fixation devices, the Milagro Interference Screw (Milagro) and the Bio-Intrafix Soft Tissue Tibial Fixation System (Bio-Intrafix). A total of 24 constructs (12 with each type of fixation) underwent biomechanical testing with 12 matched constructs undergoing uniaxial loading to failure (rate of 1 mm/sec) and the other 12 matched constructs undergoing cyclic loading (10,000 cycles at 1 Hz with a loading range of 125 to 375 N). All constructs failed by slippage of one or both ends of the anterior tibialis graft past the fixation device.

The relationship between femoral periprosthetic cortical bone geometry and porosity after total hip arthroplasty.

Stress shielding from the presence of a femoral component can cause adverse changes to cortical bone geometry and porosity leading to increased fracture risk in the periprosthetic cortical bone. The objectives of this study were to determine if porosity increased after total hip arthroplasty along the principal axes, and to determine if a relationship existed between cortical bone porosity and geometry. Ten postmortem donors allowed comparisons of implanted femurs to the contralateral nonimplanted femurs.