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Background: Infection of megaprostheses after bone tumor resection is a major concern; management is challenging. This study evaluated the survivability from such infections, the microbial isolates, treatment tactics, and outcome of megaprosthesis reconstructions., Materials and Methods: We studied 1,161 patients retrospectively who underwent megaprosthesis reconstruction for limb salvage after a sarcoma from 1983 to 2010. The mean followup was 9 y (range 3-20 y). We evaluated the overall survival of the megaprosthesis reconstructions in patients with infection and the survival with respect to the type of megaprosthesis, site of reconstruction, cemented or cementless fixation, type of tumor, adjuvant treatments, microbial isolate(s), treatment tactics, and outcome., Results: The incidence of infection was 8.6%. The most common microbial isolate was Staphylococcus epidermidis (47%). Overall survival with definitive management of infection was 88% at 10 y and 84% at 20 y. Survival was higher for cementless reconstructions and not different with respect to the type of megaprosthesis, site of reconstruction, or adjuvant therapy. Infections resolved completely with one- or two-stage surgery in 75% of patients. The rate of amputation because of infection was 21%., Conclusions: Megaprosthesis reconstructions may be infected in 8.6% of cases. Infections more commonly occur late, caused usually by S. epidermidis. The survival rate is higher with cementless megaprosthesis reconstructions and no different with respect to the type of tumor or megaprosthesis or the adjuvant treatments. One-stage revision is effective for acute post-operative infections; however, two-stage revision surgery is necessary for early and late infections. The rate of amputation because of occurrence or persistence of megaprosthesis infection is 21%.

Background: Previous studies reported on surgical indications for patients with femoral metastases. However, few studies analyzed the spectrum of femoral metastatic presentation. We performed this study to evaluate the survival of patients with femoral metastases, and clarify the treatment of femoral impending and actual pathological fractures., Materials and Methods: We retrospectively studied 110 patients with femoral metastases from various cancers treated with nailing or resection and megaprosthetic reconstruction from 1995 to 2010. The mean follow-up was 18 months. Survival was analyzed with respect to different metastatic presentations regarding gender, type of cancer, number, and location of femoral metastases, type of surgery, and pathological fracture., Results: Univariate predictors of survival were the pathological fracture and type of surgery; multivariate predictor was only the pathological fracture. Survival was significantly higher in patients with resection compared to nailing, impending compared to actual fracture, solitary metastasis and impending fracture, actual fracture treated with resection, proximal femoral actual fracture and distal femoral impending fracture treated with resection., Conclusions: Patients with femoral metastases have better survival when present with impending compared to actual pathological fracture. Although with a higher rate of complications, patients with pathological fractures of the proximal and distal femur may benefit from resection., (Copyright © 2011 Wiley Periodicals, Inc.)

Radiation-induced sarcomas are rare, high-grade sarcomas that may arise within the radiation volume at a mean latency period of 3-55 years after radiation therapy, doses of which range from 45 to 60 Gy. Radiation-induced osteosarcomas, fibrosarcomas, and malignant fibrous histiocytomas are the most common. Extensive surgery with microscopically negative-margin resection, or amputation is recommended for improved survival. Adjuvant radiation therapy and chemotherapy have not been shown to improve survival rates significantly. The prognosis is poor.

Silk from the silkworm, Bombyx mori, has been used as biomedical suture material for centuries. The unique mechanical properties of these fibers provided important clinical repair options for many applications. During the past 20 years, some biocompatibility problems have been reported for silkworm silk; however, contamination from residual sericin (glue-like proteins) was the likely cause. More recent studies with well-defined silkworm silk fibers and films suggest that the core silk fibroin fibers exhibit comparable biocompatibility in vitro and in vivo with other commonly used biomaterials such as polylactic acid and collagen. Furthermore, the unique mechanical properties of the silk fibers, the diversity of side chain chemistries for 'decoration' with growth and adhesion factors, and the ability to genetically tailor the protein provide additional rationale for the exploration of this family of fibrous proteins for biomaterial applications. For example, in designing scaffolds for tissue engineering these properties are particularly relevant and recent results with bone and ligament formation in vitro support the potential role for this biomaterial in future applications. To date, studies with silks to address biomaterial and matrix scaffold needs have focused on silkworm silk. With the diversity of silk-like fibrous proteins from spiders and insects, a range of native or bioengineered variants can be expected for application to a diverse set of clinical needs.

Advanced bioreactors are essential for meeting the complex requirements of in vitro engineering functional skeletal tissues. To address this need, we have developed a computer controlled bench-top bioreactor system with capability to apply complex concurrent mechanical strains to three-dimensional matrices independently housed in 24 reactor vessels, in conjunction with enhanced environmental and fluidic control. We demonstrate the potential of this new system to address needs in tissue engineering, specifically toward the development of a tissue engineered anterior cruciate ligament from human bone-marrow stromal cells (hBMSC), where complex mechanical and biochemical environment control is essential to tissue function. Well-controlled mechanical strains (resolution of < 0.1 micron for translational and < 0.1 degree for rotational strain) and dissolved oxygen tension (between 0%-95% +/- 1%) could be applied to the developing tissue, while maintaining temperature at 37 +/- 0.2 degrees C about developing tissue over prolonged periods of operation. A total of 48 reactor vessels containing cell culture medium and silk fiber matrices were run for up to 21 days under 90 degrees rotational and 2 mm translational deformations at 0.0167 Hz with only one succumbing to contamination due to a leak at an medium outlet port. Twenty-four silk fiber matrices seeded with human bone marrow stromal cells (hBMSCs) housed within reactor vessels were maintained at constant temperature (37 +/- 0.2 degrees C), pH (7.4 +/- 0.02), and pO2 (20 +/- 0.5%) over 14 days in culture. The system supported cell spreading and growth on the silk fiber matrices based on SEM characterization, as well as the differentiation of the cells into ligament-like cells and tissue (Altman et al., 2001).

The future of treatment of the ACL rupture is changing as our understanding of the biology surrounding the ACL continues to increase. It is our expectation that clinically applicable treatments, including the repair of the ACL and the development of a biologically engineered ACL, will occur in the next decade.

Using questionnaire and physical screening examination data for a general population of 4,962 adults aged 18 to 61 years enrolled in the Rand Health Insurance Experiment, we calculated the prevalence of 13 chronic illnesses and assessed disease impact. Low-income men had a significantly higher prevalence of anemia, chronic airway disease and hearing impairment than their high-income counterparts, low-income women a higher prevalence of congestive heart failure, diabetes mellitus, hypertension, hearing impairment and vision impairment. Of our sample, 30% had one chronic condition and 16% had two or more. Several significant pairs or "clusters" of chronic illnesses were found. With few exceptions (diabetes, hypertension), the use of physician care in the previous year for a specific condition tended to be low. Disease impact (worry, activity restriction) was widespread but mild. Persons with angina, congestive heart failure, mild chronic joint disorders and peptic ulcer disease reported a greater impact than persons with other illnesses.