The Contribution of Deleterious Rare Alleles in ENPP1 and Osteomalacia Causative Genes to Atypical Femoral Fracture.

Context: Atypical femoral fractures (AFFs) are very rare atraumatic or mild trauma fractures in the subtrochanteric region or femoral shaft. Some unique genetic variants in Asian populations might confer susceptibility to AFF, since the incidence of AFFs is higher in Asian populations.

Objective: Because rare variants have been found to be causative in some diseases and the roles of osteomalacia causative genes have not been reported, we investigated rare variants in genes causing abnormal mineralization.

Mechanical prophylaxis is a heparin-independent risk for anti-platelet factor 4/heparin antibody formation after orthopedic surgery.

Platelet-activating antibodies, which recognize platelet factor 4 (PF4)/heparin complexes, induce spontaneous heparin-induced thrombocytopenia (HIT) syndrome or fondaparinux-associated HIT without exposure to unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH). This condition mostly occurs after major orthopedic surgery, implying that surgery itself could trigger this immune response, although the mechanism is unclear. To investigate how surgery may do so, we performed a multicenter, prospective study of 2069 patients who underwent total knee arthroplasty (TKA) or hip arthroplasty.

Cytoplasmic maspin expression predicts poor prognosis of patients with soft tissue sarcomas.

Background: Maspin is a 42 kDa protein known to act as a tumor suppressor. Although its function has not been fully elucidated, numerous reports have investigated the prognostic impact of maspin in patients with several types of cancer. However, there have been no reports on the association between maspin expression and the prognosis of patients with soft tissue sarcomas (STS).

Proliferative fasciitis mimicking a sarcoma in a child: a case report.

Proliferative fasciitis (PF) is a benign, discrete proliferation of fibroblasts or myofibroblasts in soft tissue. Proliferative fasciitis mostly occurs in adults and is often confused with a sarcoma because of its rapid growth and peculiar histological features. We report a case of PF mimicking a sarcoma which developed in a 13-year-old boy, who noticed a painful tumor, with gradual enlargement, in his right lower leg.

Multiinstitutional phase II study of neoadjuvant chemotherapy for osteosarcoma (NECO study) in Japan: NECO-93J and NECO-95J.

Background: Osteosarcoma is the most frequent primary malignant bone tumor. In Europe and the United States, its prognosis has been greatly improved by the use of multimodal treatment, including preoperative and postoperative chemotherapy as well as surgery. In Japan, however, only a few clinical studies on osteosarcoma have been carried out.

Long-term follow-up after limb salvage in skeletally immature children with a primary malignant tumor of the distal end of the femur.

Background: Skeletally immature children with a primary malignant tumor in the distal end of the femur are candidates for limb-salvage surgery; however, functional impairment due to subsequent limb-length discrepancy must be considered. Our aim was to evaluate the long-term clinical outcome of limb salvage in patients with a sarcoma of the distal end of the femur who were eleven years old or less, focusing on limb-length discrepancy and complications.

Methods: The cases of forty children were retrospectively reviewed in a multicenter study based on the responses to a questionnaire.

Immunohistochemical analysis of a muscle ankyrin-repeat protein, Arpp, in paraffin-embedded tumors: evaluation of Arpp as a tumor marker for rhabdomyosarcoma.

Arpp, a protein including an ankyrin-repeat, P EST motif, and p roline-rich region, is a recently identified protein that is exclusively expressed in striated muscles. This study comprehensively analyzed its expression among soft tissue sarcomas of various histological types and evaluated its potential use for the differential diagnosis of rhabdomyosarcoma (RMS). Formalin-fixed, paraffin-embedded tissues, including 37 RMS cases, 88 non-RMS sarcomas, and 38 carcinomas, were analyzed for Arpp expression.

Development of the attachment zones in the rat anterior cruciate ligament: changes in the distributions of proliferating cells and fibrillar collagens during postnatal growth.

The development of the attachment zones of the anterior cruciate ligament (ACL) is an important consideration when examining the structural properties. The aim of this study was to elucidate the morphological changes and the distribution of proliferating cells and collagen types I, II and III at the attachment zones of the rat ACL during postnatal growth. The majority of proliferating cell nuclear antigen (PCNA) immunostained cells were noted near the ligament insertion, especially at the tibial site, and these cells gradually changed to fibrochondrocyte-like cells but still produced collagen types I and III at birth until one month old when rapid longitudinal growth of the ACL took place.