We evaluated the medium and long-term outcomes on the basis of patients' function and general quality of life after three different surgical procedures for osteosarcoma around the knee joints, that is, amputation, prosthetic reconstruction and rotationplasty. Twenty-six procedures in 22 patients who survived for at least 1 year after surgery were assessed for functional analysis (scores of the Musculoskeletal Tumor Society), and health-related quality of life assessment (SF-36) was applied to 17 patients who are alive without the disease. The patients treated with rotationplasty showed significantly high functional scores in two of six categories as compared with those undergoing the other two procedures. The scores of SF-36 also showed higher values for seven of eight subscales, however, no significant differences were observed for any subscale. We demonstrated that despite no statistical difference in patient self-assessment of outcome between the treatment modalities, there were functional benefits of rotationplasty over prosthetic reconstruction and amputation.

No abstract

Hereditary multiple exostoses (EXT) is an autosomal dominant bone disease characterized by the formation of cartilage-capped prominences. EXT is genetically heterogeneous with at least four chromosomal loci. Among the four loci, the exostosis type 1 gene (EXT1) and type 2 gene (EXT2) have been cloned. Previous studies have shown that disease-type-specific frequency of mutations is different among various ethnic populations. To determine those frequencies in the Japanese, we conducted a large-scale mutation screening on both genes. In 23 of 43 Japanese families examined, we found 21 different mutations, of which 18 are novel. Seventeen (40%) of the 23 families had a mutation in EXT1 and six (14%) had a mutation in EXT2, suggesting that the former mutations are more frequent than the latter in Japanese EXT families. Of the 17 families with EXT1 mutations, 13 had those causing premature termination of the EXT1 protein and four showed missense mutations, whereas five of the six families with EXT2 mutations had those causing premature termination and one showed missense mutation. Interestingly, all four EXT1 missense mutations occurred in an arginine residue at codon 340 (R340) that is known as a critical site for expression of heparan sulfate glycosaminoglycans, suggesting that the region encompassing the arginine residue may play an important role in the function of the EXT1 protein. These results expand our knowledge of the ethnic difference of EXT and the structure-function relationship of the EXT genes.

No abstract

We present a case of intraosseous neurilemmoma of the fibula in a 56-year-old woman. The case showed the typical radiographic appearance except for the presence of spotted calcifications that mimicked a cartilaginous tumor. Enhanced MR images revealed the heterogeneity of the tumor, which consisted of Antoni type A and B tissue.