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Dynamic cultivation using a radial flow bioreactor (RFB) has gained increasing interest as a method of achieving bone regeneration. In order to enhance bone generation in large bone defects, it is necessary to use an RFB to expand the primary cells such as bone marrow cells derived from biotissue. The present study aimed to evaluate the cell expansion and osteogenic differentiation of rat bone marrow cells (rBMC) when added to basic fibroblast growth factor containing medium (bFGFM) or osteogenic differentiation factor containing medium (ODM) under dynamic cultivation using an RFB. Cell proliferation was evaluated with a DNA-based cell count method and histological analysis. An alkaline phosphatase (ALP) activity assay and immunohistochemistry staining of osteogenic markers including BMP-2 and osteopontin were used to assess osteogenic differentiation ability. After culture for one week, rBMC cell numbers increased significantly under dynamic cultivation compared with that under static cultivation in all culture media. For different culture media in dynamic cultivation, bFGFM had the highest increase in cell numbers. ALP activity was facilitated by dynamic cultivation with ODM. Furthermore, both BMP-2 and osteopontin were detected in the dynamic cultivation with ODM. These results suggested that bFGFM promotes cell proliferation and ODM promotes osteogenic differentiation of rBMC under dynamic cultivation using an RFB.

Mesenchymal stem cells (MSCs) obtained from human bone marrow are pluripotent and have been expanded and differentiated into several kinds of mesodermal tissue in vitro. To create bioartificial tissues and organs for implantation, it is necessary to induce proliferation in such cells. In this study, a radial-flow bioreactor (RFB) was used to induce three-dimensional (3D) expansion of human MSCs (hMSCs) on a large scaffold. The effect of this expansion on cellular characteristics was investigated. To produce precultured sheets, the hMSCs were first seeded onto type 1 collagen sheets and incubated for 12 h, after which they were placed in the RFB for fabrication of scaffolds. The culture medium was circulated at 3 mL/min, and the cells were dynamically cultured for 1 week at 37°C. As a control, static cultivation in a culture dish was also carried out. Cellular expansion and characteristics were analyzed. Alkaline phosphatase (ALP) activity in the hMSCs was also investigated after dynamic culture in an osteogenesis induction medium to explore their potential for osteogenic differentiation. At 1 week of dynamic cultivation, a60% increase was observed in a number of cells together with a uniform distribution throughout the scaffolds compared with under static conditions; no change in hMSC markers was observed. The hMSCs retained the ability for osteogenic differentiation after culture in the RFB. The present results indicate that 3D dynamic culture in an RFB enables uniform expansion of hMSCs with no change in cellular characteristics, suggesting the usefulness of this technique in tissue engineering.

It is well known that in femoral head osteonecrosis patients, necrosis and collapse are usually located in the anterosuperior portion of the femoral head. We evaluated the usefulness of a “look-up” plane X-ray view of osteonecrosis for early detection of femoral head collapse. We examined 20 joints in 17 patients. Osteonecrosis was classified into four stages according to radiographic signs (demarcation line, crescent line, collapse and joint space narrowing). Eight joints were classified as stage 2 and 12 joints as stage 3. Collapse, crescent line and demarcation line were evaluated on three types of radiographs; ordinary anteroposterior (AP) and lateral views and the “look-up” view. Seventeen of the 20 hips clearly showed more than 2mm collapse on the “look-up” view. The incidence of clear collapse was higher than that on the AP view. The incidence of crescent line was also higher. There were no significant differences in the demarcation line between the look-up view and AP view. Magnetic resonance imaging and tomography are useful and routinely used to define necrotic lesions. However, the “look-up” view is a simple and inexpensive method for the early detection of femoral head collapse in osteonecrotic patients.

Chondrosarcoma arising from the thoracic vertebra is rare. Total excision in such cases is quite difficult because of its proximity to the vital structures such as the spinal cord, aorta, etc. Here we report two cases arising from the thoracic spine-One involved the T7 to T10 vertebral bodies and ribs and the other the T4 to T7. Both cases were histopathologically diagnosed as chondrosarcoma (Gradel) by open biopsy.The lesions were surgically removed through thoracotomy. The chest wall defects were reconstructed with Marlex meshes and posterior spinal instrumentations were employed in both cases.Preoperative detailed evaluation by MRI and CT is necessary for the surgical procedure for such tumors.

Arthroscopic and arthrographic studies of the osteoarthritic hip joint showed that cartilage degeneration generally originates in the anterosuperior position of the weigth-bearing area. We evaluated the usefulness of a “look-up” plane X-ray view of osteoarthrotic hip joints for early detection of joint space narrowing or articular cartilage wear in the anterosuperior weight-bearing area of the joints. We examined 34 hips of 23 patients consisting of 6 normal joints and 28 coxarthrosis. The coxarthrosis were classified into four stages according to joint space narrowing: prearthritic stage (6 patients), early-stage (5 patients), advanced-stage (10 patients), and end-stage (7 patients). The wiath of the joint space was measured on four types of radiographs in each patient; lying down view, standing up view, lying down look-up view, and standing up look-up view. The joint space on the look-up view in most hips in the prearthritic stage tended to increase in comparison with anteroposterior radiograpf, while one hip joint judged as prearthritic stage showed narrowing of the jont space. The joint space of the hips in the early and advanced stages tended to decrease. There were two cases of early-stage whose look-up views showed joint space narrowing and were judged as advanced stage. In conclusion, the lool-up view reflects cartilage wear in the anterosuperior position and is useful for early detection of joint space narrowing.

We attempted to quantify periarticular bone atrophy from radiographs of the proximal phalanx in patients with rheumatoid arthritis (RA) by means of the National Institutes of Health (NIH) Image computer program. The degree of brightness or darkness in four squares, each 20 × 20 pixels, in the right third proximal phalanx was measured using NIH Image, and the mean value of the 400 pixels was defined as the brightness/darkness index (BDI). The BDI was used to express bone volume. The BDI value was set at zero for an area of complete darkness and at 255 for an area of maximum brightness. The mean coefficient of variation in our hospital was 2.28%. The BDI was measured in 54 RA patients and 146 normal volunteers. The mean BDI at the midpoint of the diaphysis was 100 in RA patients and 176 in normal volunteers, while at the medial side of the proximal end it was 75 and 145, respectively. The difference between normal volunteers and RA patients was greatest in younger people. In some young RA patients, the BDI was significantly low at the medial side of the proximal end, clearly demonstrating periarticular bone atrophy. Periarticular bone atrophy can be quantified using the NIH Image computer program.

Three cases of sternal segment dislocation in children are described. The primary mechanisms were direct blow in a 4-year-old boy, indirect forces in a 3-year-old boy, and osteomyelitis in a 10-year-old boy. The two former cases were dislocated at the junction of the manubrium with the sternal body, and the latter case was at the junction of the first and second sternal segments. The dislocated segments were gradually rotated for approximately 2 weeks and were finally stabilized after rotation. While in the dislocated state, the patients were observed conservatively, although all the dislocated segments were remodeled. Surgical treatment of sternal segment dislocation is not inevitable.

We report a case of physeal arrest secondary to extravasation of an intravenous infusion in a neonate. The ankle was reconstructed according to the Gruca operation followed by callus distraction lengthening.

Three cases of sternal segment dislocation in children are described. The primary mechanisms were direct blow in a 4-year-old boy, indirect forces in a 3-year-old boy, and osteomyelitis in a 10-year-old boy. The two former cases were dislocated at the junction of the manubrium with the sternal body, and the latter case was at the junction of the first and second sternal segments. The dislocated segments were gradually rotated for approximately 2 weeks and were finally stabilized after rotation. While in the dislocated state, the patients were observed conservatively, although all the dislocated segments were remodeled. Surgical treatment of sternal segment dislocation is not inevitable.