Effects of blood on bone cement made of calcium phosphate: problems and advantages.

In recent years, calcium phosphate cements (CPCs) have frequently been used as bone substitutes in the field of orthopedic surgery. When CPC is used as a bone substitute in vivo, blood contamination is unavoidable. To date, however, no detailed study has been conducted focusing on how the physical properties of CPCs would change under the influence of blood. In this study, the effects of blood contamination on Biopex-R (BPR, PENTAX, Tokyo) are examined in vitro and in vivo. The compressive strength of BPR after setting decreased depending on the amount of contaminating blood. The BPR, which has set in vivo, not only has a fragile surface due to the contamination by blood, but also has a propensity to shorten and be destroyed during the early postoperative stage, especially in the bone exposed to loads. On the other hand, radiographic and histological features in vivo indicated that the absorption and the bone replacement of BPR were stimulated by blood contamination. In the clinical evaluation, the patient's own peripheral venous blood was added to the BPR. One year after the surgery, the absorption was noted around the hardened BPR. To advance CPCs (including BPR) as bioabsorbable bone replaceable materials, it is essential to utilize the patient's own blood in combination with the CPC.

A Japanese patient with Li-Fraumeni syndrome who had nine primary malignancies associated with a germline mutation of the p53 tumor-suppressor gene.

We describe a patient who had nine primary malignant tumors and a germline mutation in the p53 tumor-suppressor gene, characteristically found in the Li-Fraumeni syndrome (LFS). A 15-year-old girl with no family history of cancer was referred to our hospital because of pain and swelling of the right knee. Osteosarcoma was diagnosed. The patient received chemotherapy followed by surgery and had a remission. After the age of 28 years, nine primary malignant tumors developed successively, including right breast cancer, colon cancer, malignant fibrous histiocytoma (MFH) of the abdominal wall, right lung double cancers, bilateral breast cancers, and MFH of the left thigh. This is the second highest number of types of primary malignant tumors to be reported in LFS. All tumors were treated by a multidisciplinary approach, including surgery. Genetic analysis revealed a germline missense mutation in the p53 gene (c.659 A > G), resulting in Y220C, which has been reported in three families with LFS. The patient died of lung metastasis from MFH at the age of 37 years. Despite the multiple tumors, repeated induction of remissions resulted in long survival. Our findings suggest that a multidisciplinary approach to treatment, including surgery, is beneficial in patients with LFS.

Innervation of the triangular fibrocartilage complex of the human wrist: quantitative immunohistochemical study.

The distribution of neural elements in the triangular fibrocartilage complex (TFCC) of the human wrists was studied via immunohistochemical staining of protein gene product (PGP) 9.5 and calcitonin gene-related peptide (CGRP). Articular branches projecting to the TFCC arose from the dorsal branch of the ulnar nerve in all wrists examined. The TFCC is subdivided into the following six regions: the articular disc proper (ADP), meniscus homolog (MH), radio-ulnar ligament (RUL), loose part of ulnar collateral ligament (lUCL), dense part of ulnar collateral ligament (dUCL), and internal portion (IP). The IP consists of a mixture of dense and loose connective tissues enclosed by the ADP, MH, RUL, and UCL, and resides deep in the prestyloid recess, which is a pit in the MH. The densities of PGP 9.5-positive neural elements, including free nerve endings, single nerve fibers, nerve fascicles, and perivascular neural nets, were significantly higher in the IP than in other regions. Some of the neural elements except for the perivascular neural nets were positive for CGRP. The high density of neural elements in the IP suggests that sensory nerves projecting to the TFCC enter into the IP and from there distribute to adjacent regions such as the MH and RUL. Free nerve endings are responsible for pain transmission. The high density of free nerve endings in the IP suggests that the IP is a source of ulnar side wrist pain.

Surgery for dedifferentiated liposarcoma, presenting two radiologically and pathologically distinctive patterns.

In this paper, we report three cases with dedifferentiated liposarcoma in the lower extremities, presenting two patterns that are distinctively different radiologically and pathologically. The first case was a 67-year-old male who had discovered a mass in his left thigh, which was shown as a low and iso density mass between the muscles on computed tomography (CT). The second case was a 61-year-old male who had suffered from an intramuscular tumor with a non-fatty sarcomatous area within the fatty components as shown on magenetic resonance imaging (MRI). The third case was a 52-year-old female who had presented with an intramuscular tumor of the left thigh, consisting of a mass with fat and another soft tissue tumor adjacent to the lipomatous component as detected with CT and MRI. The final pathological diagnoses of the resected specimens in all three cases were concluded to be dedifferentiated liposarcoma, composed of well-differentiated liposarcomas and spindle and/or pleomorphic sarcomas, compatible with malignant fibrous histiocytoma. In all three cases, wide resection of the tumor was successfully carried out, and all patients have been continuously disease-free up to the most recent follow-up. Evaluation of the surgical margins for the resected specimens indicated that the safety margin for a dedifferentiated lesion should be accomplished as an adequate margin or more, and a marginal margin or more could be considered as safe only for the confined part of a well-differentiated liposarcoma.

Malignant change secondary to fibrous dysplasia.

BACKGROUND: Malignant change in fibrous dysplasia (FD) is very rare. This study was carried out to establish some characteristic clinical information about this disorder. METHODS: Four cases with a malignant change in FD out of 128 cases with FD were surgically treated and followed up for a median period of 61.3 months. The mean age of the patients was 39.8 years. Clinical features, radiological findings, and the outcome were analyzed for each of the four cases. RESULTS AND CONCLUSION: The sites of the lesions were tibia (2 cases), femur (1 case), and rib (1 case). The forms of FD were monostotic in one case and polyostotic in three cases. Radiologically, plain films and computed tomography (CT) showed osteolytic lesions with poorly delineated margins within and/or near areas having a ground-glass appearance. In the osteolytic lesions, simple cystic changes associated with old FD could be excluded by enhanced magnetic resonance imaging (MRI). Histopathologically, two cases were osteosarcoma, one case was malignant fibrous histiocytoma (MFH), and one case was fibrosarcoma. The management of this disease should be decided according to the type of primary high-grade bone sarcoma. One patient, with MFH, was dead of lung metastasis 13 months after surgery. The others are alive without disease.

Oncologic outcome of parosteal osteosarcoma.

BACKGROUND: This retrospective review evaluated the clinical features and surgical outcomes of parosteal osteosarcoma (POS). METHODS: Nine patients were surgically treated and followed up. Their mean age was 30.8 years. Clinical information and oncologic outcomes of each case were analyzed. RESULTS: Sites of involvement were all in the femur, and all tumors arose from the metaphyseal area of the distal femur. Biopsies for definite diagnoses were performed in just two of the nine cases. Wide resection was applied for all tumors. Surgical evaluations were a 1-cm-wide procedure in six cases and a 2-cm-wide procedure (or more) in three cases. All patients were found to be continuously disease free during the follow-up period of 115.1 months. CONCLUSION: POS showed characteristic findings on radiographic images. Therefore, wide resection without biopsy could be performed in 77.8% (7/9) of the cases. This procedure may contribute to attaining better limb function, because of preventing contamination of healthy surrounding tissue and minimizing the extent of resection. The safety margin was evaluated as a 1-cm-wide procedure. For the choice of reconstruction, indication of autobone grafting (3/9) or total knee replacement (TKR) (6/9) depended on tumor size, location, and shape. With no adjuvant treatments, all cases have shown good clinical courses during the entire follow-up period of about 10 years.

Report of four cases with high-grade surface osteosarcoma.

High-grade surface osteosarcoma is the rarest of the three types of surface osteosarcoma. Four cases with high-grade surface osteosarcoma arising from the distal femur and tibia are reported in this study. One patient was previously diagnosed with Turner's syndrome. Radiologically, three cases presented characteristic appearances suggesting high-grade bone-forming sarcoma arising from the bone surface; however, one case was similar to other juxtacortical lesions such as periosteal and parosteal osteosarcoma, which typically have a better prognosis than high-grade surface osteosarcoma. Therefore, all cases underwent biopsy to determine a definitive diagnosis. Our strategy of treatment for high-grade surface osteosarcoma was a combination of wide resection and pre-/post-operative chemotherapy, equivalent to the treatment for conventional intramedullary osteosarcoma. At the last follow-up, two cases were still undergoing chemotherapy, one case was continuously disease free during the follow-up period of 81 months, and one patient was living with no evidence of disease 60 months after surgery. The aim of this study is to report the clinical information, oncological outcome and appropriate treatment for high-grade surface osteosarcoma.