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Purpose: Antibacterial iodine-supported titanium has an anodized oxide layer; thus, it can be expected to have a higher osteoconductivity than untreated titanium. This study aimed to compare the osteoconductivity between untreated titanium (Ti), anodically oxidized titanium (AO-Ti), and iodine-supported titanium (I-Ti) screws. Methods: The screws were inserted into the vertebral bodies of 30 dogs (12 for the biomechanical, and 18 for the histological examination). The vertebral bodies were analyzed at 4 or 8 weeks after screw insertion. Biomechanically, rotational torque of the screw was measured. Histologically, bone formation index (ratio of the length of the part where the bone directly contacts with the length of the screw) and bone volume density (ratio of the area of the bone tissue to the area between the threads of the screw) were measured. Result: At 4 weeks, the torque value was significantly higher in the AO-Ti (0.59 ± 0.16 Nm) and I-Ti (0.72 ± 0.14 Nm) groups than in the Ti group (0.39 ± 0.12 Nm), with the AO-Ti and I-Ti groups showing no significant difference. Bone formation index was significantly higher in the AO-Ti (72.5% ± 0.8%) and I-Ti (73.4% ± 1.5%) groups than in the Ti group (64.6% ±1.7%), with the AO-Ti and I-Ti groups showing no significant difference. Bone volume density did not show a significant difference. At 8 weeks, the results were similar to those at 4 weeks. Conclusions: I-Ti had a higher osteoconductivity than Ti, indicating that iodine coating did not adversely affect osteoconductivity. [ABSTRACT FROM AUTHOR]

Purpose: CD81 is a member of the tetraspanin family of membrane proteins. Recently, it has been shown that CD81 may be involved in cancer cell proliferation and metastasis. As yet, however, there have been few reports on the expression and role of CD81 in osteosarcoma. Methods: The expression of CD81 was investigated in human osteoblast cell line hFOB1.19 and in human osteosarcoma cell lines Saos2, MG63 and 143B. The expression of CD81 was inhibited in osteosarcoma cells using siRNA after which cell proliferation, migration and invasion were assessed. We also used Western blotting to investigate the phosphorylation status of Akt, Erk, JNK and p38, and measured the expression of MMP-2, MMP-9 and MT1-MMP. In addition, we used a CRISPR/Cas9 system to stably knock out CD81 expression in 143B cells, transplanted the cells into mice, and assessed tumor formation and lung metastasis in these mice compared to those in the control group. Results: We found that CD81 was expressed in the human osteoblast cell line and in all osteosarcoma cell lines tested. The osteosarcoma cell line 143B exhibited a particularly high level of expression. In addition, we found that osteosarcoma cell proliferation, migration and invasion were decreased after CD81 inhibition, and that the phosphorylation of Akt and Erk was suppressed. Also, the expression levels of MMP-2, MMP-9 and MT1-MMP were found to be suppressed, with MMP-9 showing the greatest suppression. In vivo, we found that mice transplanted with CD81 knockout 143B cells exhibited significantly less tumor formation and lung metastasis than mice in the control group. Conclusion: Based on our findings we conclude that inhibition of CD81 suppresses intracellular signaling and reduces tumorigenesis and lung metastasis in osteosarcoma cells. [ABSTRACT FROM AUTHOR]

We herein report a rare case of mesenchymal hamartoma of the chest wall in a 10-year-old girl. She complained of chest pain and was diagnosed with a large chest wall tumor originating from the left fourth rib. Malignancy such as osteosarcoma or chondrosarcoma could not be ruled out with imaging studies. Therefore, we performed a core needle biopsy assisted by thoracoscopy, which revealed no malignancy. Therefore, extended resection with chest wall reconstruction was unnecessary, and thoracoscopy-assisted tumor excision with only the removal of the involved fourth rib was performed without chest wall reconstruction. The postoperative course was satisfactory with no thoracic deformity and no recurrence. [ABSTRACT FROM AUTHOR]

Although advances in chemotherapy have improved the prognosis for osteosarcoma, some patients do not respond sufficiently to treatment. Heat shock protein 70 (Hsp70) is expressed at high levels in cancer cells and attenuates the therapeutic efficacy of anticancer agents, resulting in a poorer prognosis. This study investigated whether small interfering RNA (siRNA)-mediated inhibition of Hsp70 expression in an osteosarcoma cell line would enhance sensitivity to cisplatin. The expression of Hsp70 with cisplatin treatment was observed by using Western blotting and real-time reverse transcription polymerase chain reaction (RT-PCR). Changes in the IC of cisplatin when Hsp70 was inhibited by siRNA were evaluated. Cisplatin's effectiveness in inducing apoptosis was assessed by assay of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), caspase-3 activity, and mitochondrial membrane potential. Up-regulation of Hsp70 expression was dependent on the concentration of cisplatin. Inhibition of Hsp70 expression significantly reduced the IC of cisplatin. When cisplatin was added to osteosarcoma cells with Hsp70 expression inhibited, a significant increase in apoptosis was demonstrated in TUNEL, caspase-3, and mitochondrial membrane potential assays. Inhibition of Hsp70 expression induced apoptosis in cultured osteosarcoma cells, indicating that Hsp70 inhibition enhanced sensitivity to cisplatin. Inhibition of Hsp70 expression may provide a new adjuvant therapy for osteosarcoma. [ABSTRACT FROM AUTHOR]

Purpose: We have developed iodine-supported titanium implants that suppress microbial activities and conducted in vivo and in vitro studies to determine their antimicrobial properties.Methods: The implants were Ti-6Al-4 V titanium implants either untreated (Ti), treated with oxide film on the Ti surface by anodization (Ti-O), or treated with an iodine coating on oxidation film (Ti-I). The strain of bacteria used in this study was Gram-positive Staphylococcus aureus strain ATCC 25923. We analyzed the antibacterial attachment effects in vivo by using rats. The attachment bacteria on the implant surface were evaluated using a spread-plate method assay. A biofilm study was performed in vitro. The biofilm formed after bacterial attachment was qualitatively studied with fluorescence microscopy (FM) and scanning electron microscopy (SEM). Also, the formed biofilm was quantitatively studied with a spread-plate method assay.Results: In vivo analysis of antimicrobial attachment effects showed that the mean viable bacterial number was significantly lower on Ti-I than Ti or Ti-O surfaces. In the in vitro biofilm study, FM and SEM images showed thick and mature biofilm formation on Ti and Ti-O and thin, small biofilm formation on Ti-I. A quantitative biofilm analysis found a significant difference in the number of viable bacteria between Ti-I and Ti or Ti-O.Conclusions: This study showed that iodine-supported implants have a good antibacterial attachment effect and inhibit biofilm formation and growth. Iodine-supported implants may have great potential as innovative antibacterial implants that can prevent implant related infection in orthopaedic surgery. [ABSTRACT FROM AUTHOR]

Purpose: It has previously been found that valgus hindfoot alignment (HFA) improves 3 weeks following total knee arthroplasty (TKA) for varus knee osteoarthritis (OA). In the present study, HFA was evaluated prior to TKA, as well as 3 weeks and 1 year following TKA. Using these multiple evaluations, the chronological effects of TKA on HFA were investigated.Methods: The study included 71 patients (73 legs) who underwent TKA for varus knee OA. Radiograph examinations of the entire limb and hindfoot were performed in the standing position prior to TKA, as well as 3 weeks and 1 year following TKA. The varus-valgus angle was used as an indicator of HFA in the coronal plane. Patients were divided into two groups according to the preoperative varus-valgus angle: a hindfoot varus group (varus-valgus angle <76°) and a hindfoot valgus group (varus-valgus angle ≥76°). The changes in the varus-valgus angle were evaluated and compared in both groups.Results: In the hindfoot valgus group, the mean ± standard deviation varus-valgus angle significantly declined from 80.5 ± 3.1° prior to TKA to 78.6 ± 3.7° 3 weeks following TKA and 77.1 ± 2.7° 1 year following TKA. However, in the hindfoot varus group, the mean varus-valgus angle prior to TKA (72.7 ± 2.6°) did not differ significantly from the mean varus-valgus angles 3 weeks (72.3 ± 3.3°) or 1 year (73.5 ± 3.0°) following TKA.Conclusions: HFA improved chronologically in legs with hindfoot valgus as a result of the alignment compensation ability of the hindfoot following TKA. However, no improvement was noted in legs with hindfoot varus because the alignment compensation ability of the hindfoot had been lost. The patients with hindfoot varus should be attended for ankle pain in the outpatient clinic after TKA.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Purpose: In this study, magnetic resonance angiography (MRA) was performed in the early phase after anterior cruciate ligament (ACL) reconstruction to analyse the changes in nutrient blood vessels and blood flow to the femoral and tibial tunnels and the intraosseous tendon grafts.Methods: The subjects were 30 patients who underwent single-bundle ACL reconstruction with an autogenous hamstring tendon. MRA was performed at 2, 3, and 6 months postoperatively (n = 10 at each time point). The mean overall signal-to-noise ratios (SNRs) in the tunnel regions and in the region of the tendon graft were compared in each femur and tibia.Results: Blood vessels from arteries reached the femoral and tibial tunnels 2 months postoperatively. The tunnel walls showed high signal intensity, while the intraosseous tendon grafts had lower intensity. SNRs showed significant differences between the femoral and tibial tunnels overall and the intraosseous tendon grafts. At 3 and 6 months postoperatively, the signal intensity of the tunnel walls was decreased significantly, while that of the intraosseous tendon grafts was also decreased, but not significantly. At these times, the SNRs of the femoral and tibial tunnels did not differ significantly, both overall and in the region of the intraosseous tendon grafts.Conclusion: Revascularization around the femoral and tibial tunnels occurred at 2 months postoperatively, with blood flow subsequently decreasing over time until 6 months. This revascularization may be involved in bone tendon healing and maturation of the tendon graft within the bone tunnels. Evaluations of revascularization by MRA may show the maturation stage of the graft and guide medical rehabilitation.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Background: Low-grade osteosarcoma, including low-grade central osteosarcoma and parosteal osteosarcoma, is an extremely rare variant, and the diagnosis is occasionally difficult. In this article we present cases of low-grade osteosarcomas that should be reviewed by a clinical oncologist. Patients and methods: Nine cases of histologically diagnosed Broder grade 1 osteosarcoma were retrospectively reviewed. The pathological diagnoses included parosteal osteosarcoma, low-grade central osteosarcoma, and low-grade chondroblastic osteosarcoma in four, four, and one cases, respectively. Results: Duration from initial surgical intervention including biopsy to final diagnosis as low-grade osteosarcoma was a mean of 9.4 months. The initial benign diagnoses on biopsy specimens included fibrous dysplasia in three cases, chondroblastoma in one case, and a giant cell tumor in one case. The average number of histological examinations was 1.8. Low-grade osteosarcomas are well suited for biological reconstruction: seven cases were reconstructed by frozen autografts, distraction osteogenesis, or vascularized bone grafts. Conclusion: Low-grade osteosarcomas can be misdiagnosed as benign lesions, especially fibrous dysplasia. If the diagnosis of a low-grade osteosarcoma is not established on the basis of radiologic findings, care should be exercised, even when a biopsy suggests a benign lesion. Low-grade osteosarcomas should be treated with wide excision, even after an intralesional excision. Biological reconstruction might be a better option for low-grade osteosarcomas. [ABSTRACT FROM AUTHOR]

Background: Clear cell sarcoma is a rare malignant tumor of soft tissue which is most commonly encountered in the extremities, especially in the foot and ankle. This tumor is slow-growing and looks like a benign tumor; it is therefore often treated inadequately and its high rate of recurrence and metastases results in a poor prognosis. Caffeine has been used as a chemotherapy potentiator that inhibits DNA damage repair and enhances the cytocidal effects of anti-cancer drugs. This study reports the effect of caffeine-potentiated chemotherapy for clear cell sarcoma in five patients. Methods: Caffeine-potentiated chemotherapy was administered to five patients with clear cell sarcoma. Three to five courses of intra-arterial chemotherapy using cisplatin, doxorubicin and caffeine were administered preoperatively, at 3-week intervals. Conservatively, wide margin surgery was performed following the preoperative chemotherapy. Intravenous cisplatin and doxorubicin with caffeine were administered three to six times to the patients who responded to the preoperative chemotherapy. This study evaluated the response to chemotherapy, recurrence, metastasis and the overall prognosis in these five patients. Results: Four of the eligible patients responded to preoperative chemotherapy. Local recurrence occurred in only one of the five patients. Distant metastasis newly developed in one patient. All five patients survive. Conclusion: Caffeine-potentiated chemotherapy can be effective treatment for clear cell sarcoma not only as initial therapy, but also as salvage therapy. [ABSTRACT FROM AUTHOR]

Background: The shoulder girdle is a common site for malignant bone and soft tissue tumors. Total scapulectomy represents an attractive alternative to amputation when the whole scapula is invaded with tumor and the neurovascular bundle can be preserved during tumor resection. The purpose of this study was to investigate functional outcomes after total scapulectomy. Patients and methods: The study comprised seven patients, four of whom underwent soft tissue reconstruction for joint stabilization, including suture of the biceps tendon onto the clavicle or humeral head, reattachment of the rotator cuff, and/or humeral suspension. The remaining three patients did not undergo soft tissue reconstruction; instead, only the remaining muscles were sutured. Results: Mean Enneking functional score was 57%. Preservation of elbow, wrist and finger motion resulted in an acceptable level of postoperative limb function. No significant differences in function were observed between the soft tissue reconstruction group and the non-reconstruction group. Conclusion: Total scapulectomy is a feasible alternative to amputation as it preserves acceptable elbow and hand function. [ABSTRACT FROM AUTHOR]

Background: In the treatment of osteosarcoma, the chemotherapeutic effect influences decisions regarding the surgical margin, continuation of chemotherapy, and choice of anticancer drugs for further chemotherapy. Therefore, it is necessary to evaluate the response to chemotherapy in the middle of the chemotherapy course. In this study, we investigated the use of Tc-hexakis-2-methoxyisobutyl-isonitrile (Tc-MIBI) scintigraphy in evaluating the response to chemotherapy of patients with osteosarcoma in comparison with Tl scintigraphy and angiography. Methods: A total 45 patients with osteosarcoma were examined using Tc-MIBI scintigraphy, Tl scintigraphy, and angiography to evaluate their response to chemotherapy. The percentage reduction in the uptake ratios (ΔUR) calculated as 100 × [(prechemotherapy value − postchemotherapy value)/prechemotherapy value] were compared with histological assessments. Similarly, changes in tumor vascularity assessed by angiograms were compared with histological assessments. On the angiographic findings, the results were classified as complete response (CR), partial response (PR), no change (NC), or progressive disease (PD). On the images, ΔUR in Tc-MIBI ≥ 30% and ΔUR in Tl ≥ 30% were classified as responder, as were CR and PR in angiograms. The therapeutic effect was assessed by histopathological examination of the resected specimens. The tumors of poor responders showed less than 90% necrosis, whereas the tumors of good responders showed 90% or more necrosis. Results: Sensitivity, specificity, and accuracy were 73.9, 84.2, and 78.6%, respectively, for Tc-MIBI (κ = 0.57); 80.0, 61.1, and 72.1%, respectively, for Tl (κ = 0.42); and 91.7, 35.0, and 65.9%, respectively for angiography (κ = 0.28). Conclusion: Tc-MIBI could be effectively used to predict the final response to chemotherapy of osteosarcoma. [ABSTRACT FROM AUTHOR]