Clinical and Economic Outcomes of Patients with Osteoporosis Undergoing Spine Fusion Surgery in Japan.

Introduction: Spinal fusion surgery with instrumentation is a treatment of choice for many spinal disorders; however, there is little data related to factors associated with early and late outcomes, especially among patients with poor bone quality (e.g., osteoporosis). We conducted this study to characterize the epidemiology and outcomes of patients undergoing spinal fusion surgery with instrumentation in Japan, especially in patients with poor bone quality and those needing additional fixation methods. Methods: This retrospective observational study used real-world health insurance claims data from the Japanese Medical Data Vision. Adult patients undergoing an index spinal fusion procedure from April 1, 2010, to September 30, 2017, with procedural details, length of stay (LOS), total in-hospital costs, spine-related reoperation, all-cause readmission, and postoperative complications recorded. Data were summarized descriptively overall, by osteoporosis status, and additional fixation method used, and were analyzed in bivariate analyses. Multivariate logistic and linear regressions were used to explore associations between covariates and variables of interest. Results: A total of 22,932 patients (mean age, 67.3 years; 51.2% male) met the study criteria and were included. A total of 5,288 (23.0%) patients had osteoporosis, and 2,507 (10.9%) needed additional fixation methods; these patients were older, more frequently female, and had higher Elixhauser comorbidity index scores. Osteoporosis and additional fixation use were also associated with longer LOS, higher hospital costs, and higher rates of complications. Conclusions: Patients with osteoporosis and those needing additional fixation methods have a higher risk for procedural and postoperative complications, reoperation, longer LOS, and higher total hospital costs.

Differential Diagnosis of Lipomatous Tumors Using 18F-Fluorodeoxygulcose Positron Emission Tomography/Computed Tomography: A Retrospective Observational Study.

Background/Aim: Lipomatous tumors, including lipomas, atypical lipomatous tumors (ALTs), myxoid liposarcomas (MLs), and dedifferentiated liposarcomas (DLs), are often diagnosed using magnetic resonance imaging (MRI). Differential diagnosis of lipomas and ALTs by MRI is often challenging. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has recently been used for the diagnosis and evaluation of tumor staging and recurrence of soft tissue tumors. The maximum standardized uptake value (SUVmax) is positively associated with malignant grade in several cancers. This study aimed to evaluate SUVmax of 18F-FDG PET/CT in the differential diagnosis of lipomatous tumors. Patients and Methods: Patients who underwent 18F-FDG PET/CT for the diagnosis of lipomatous tumors between January 2013 and September 2021 were included in the study. Patients with lipomatous tumors, confirmed by pathological diagnosis or surgical specimens, were evaluated for lipomatous tumor SUVmax. Results: This study included 44 patients with lipomas (n=19), ALTs (n=12), MLs (n=9), and DLs (n=4). The mean SUVmax of lipomas, ALTs, MLs, and DLs was 0.99±1.41, 1.92±0.95, 5.21±4.94, and 9.29±1.43, respectively. Lipomas showed a significantly lower SUVmax than did ALTs, MLs, and DLs (p<0.05). ALTs demonstrated a significantly lower SUVmax than did MLs and DLs (p<0.05). No significant differences were observed between MLs and DLs. Conclusion: Lipomas or ALTs had a significantly lower SUVmax than lipomatous sarcomas. Lipomas had a significantly lower SUVmax than ALTs, aiding in their preoperative differentiation. 18F-FDG-PET/CT could serve as a potent tool for the differential diagnosis of lipomatous tumors.

Total hip arthroplasty after failed transtrochanteric rotational osteotomy for osteonecrosis of the femoral head: analysis of three-dimensional morphological features.

BACKGROUND: In total hip arthroplasty (THA) after failed transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head (ONFH), deformity of the proximal femur has been reported to affect stem placement. The aims of this study were to evaluate the morphological changes in the proximal femur, muscle atrophy, and soft tissue thickening in THA after TRO and the clinical outcomes. METHODS: The TRO group included 17 patients (18 hips) who underwent THA after failed TRO. The control group included 21 patients (28 hips) who underwent primary THA for ONFH. To evaluate the deformity of the proximal femur before THA, we measured the anteroposterior and mediolateral diameters of the femur on computed tomographic slices 5 mm proximal to the lesser trochanter. To evaluate muscle atrophy and soft tissue thickening, we measured the thicknesses of the psoas major, iliac, and gluteus medius muscles and the anterior capsule of the hip joint. RESULTS: The ratio of the anteroposterior to mediolateral diameters of the proximal femur was significantly greater in the TRO group (p < 0.01). The thicknesses of the muscles did not differ between the two groups, whereas the anterior capsule was significantly thicker in the TRO group (p < 0.05). Varus or valgus stem alignment (> 3°) was frequent in the TRO group (p < 0.01). CONCLUSIONS: The round shape of the proximal femur was deformed after TRO compared with primary THA for ONFH, which may have caused malposition of the stem. In addition, we should pay attention to anterior protrusion of the proximal femur and thickening of the anterior capsule.

Rare coexistence of multiple osteochondromas and solitary osteoid osteoma: A case report.

Multiple osteochondromas (MOs) are inherited in an autosomal-dominant manner, with a penetrance of ~96 and 100% in female and male patients, respectively. Osteochondromas primarily involve the metaphyses and diaphyses of long bones, including the ribs. Osteoid osteomas account for ~3 and 11% of all bone tumors and benign bone tumors, respectively. Furthermore,1 the male-to-female ratio is 2-3:1, and they generally occur in the long bones of the lower extremities, with the femoral neck being the most frequent site. The present study describes the case of a 16-year-old male patient with a bony mass around the left knee joint and pain in the left calf. Radiography revealed MOs in the upper and lower extremities, while computed tomography showed a nidus in the cortex of the tibial shaft. The patient's family history included the presence of MOs, and the patient was diagnosed with MOs and a solitary osteoid osteoma. Surgical excision of the osteochondroma and curettage of the osteoid osteoma in the proximal tibia and tibial shaft, respectively, were performed simultaneously. Postoperative pathological examination revealed osteochondroma and osteoid osteoma. Furthermore, the pain resolved, and no recurrence was observed 7 months post-operation. To the best of our knowledge, no reports exist on coexisting MOs and osteoid osteoma; therefore, the present study describes the first case of such a condition. Marginal excision for osteochondroma and curettage for osteoid osteoma effectively improved the symptoms.

Significant removal of bacterial biofilm induced by multiple-Short ranges of electric interventions.

BACKGROUND: Biofilm-related infections are serious problems in the Orthopedics field, and Staphylococcus aureus are the most popular causative agents of bacterial infections associated with arthroplasty. Several studies demonstrated a synergistic effect of the electric intervention (EI) and the antibiotic administration in killing bacteria in biofilm; however, a constant, long-time EI was needed. In the present study, the effective removal of biofilm formed with S. aureus on a titanium ring by multiple times of one minute-EI was observed and described. METHODS: A methicillin-sensitive S. aureus clinical isolate was used to form biofilm on a titanium ring. After applying a series of EI with various combinations of the frequencies and timings, the amount and principal components of biofilms were assessed with crystal violet staining, live bacterial cell count, and fluorescence staining with confocal laser scanning microscopy. RESULTS: More than 60% biofilm removal was observed in the 2-time EI applied at 24 (1) and 72 (3) h (days) post bacterial exposure (PBE) and in the 3-time EI at 0 (0), 24 (1), and 72 (3) h (days) PBE, or at 24 (1), 48 (2), and 72 (3) h (days) PBE. The live bacterial cell numbers, the proportion of live and dead cells, and the amount of extracellular polysaccharide substances (EPS) of biofilm were similar with or without EI. It was assumed that an excess amount of the biofilm removal shown in the several EI was not attributed to the effect of the electrolysis. CONCLUSIONS: The effective removal of biofilm was observed when multiple times 1 min EI was applied without any changes in the proportion of live and dead bacteria or the amount of EPS. The mechanisms to explain extra biofilm removal remain to be elucidated.

Oncological and functional outcomes of modified arthroscopic resection for intra-articular tenosynovial giant cell tumor of the knee using multiple portals.

BACKGROUND: Arthroscopic resection of tenosynovial giant cell tumor (TS-GCT) presents favorable outcomes. However, there are reportedly higher recurrence rates in patients who had incomplete resection. To minimize incomplete resection, we established a multiple portal approach depending on the location of the disease. In this study, we aimed to retrospectively evaluate the clinical outcomes of arthroscopic resection for both localized and diffuse types of TS-GCT of the knee. METHODS: From 2009 to 2019, 13 patients who underwent arthroscopic synovectomy of the knee and were histologically diagnosed with TS-GCT were included in this study. The pre- and postoperative range of motion (ROM) of the knee was measured. The Japanese Orthopaedic Association (JOA) score and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were assessed at the final follow-up examination. Magnetic resonance imaging was performed to detect incomplete resection or local recurrence. RESULTS: Among the 13 patients, seven and six had localized and diffuse type TS-GCT, respectively. Regarding the knee ROM, preoperative knee flexion in patients with the localized type was limited compared with that in those with the diffuse type. However, the ROM was significantly improved in patients with both types postoperatively. The JOA score and KOOS of patients with both types at the final follow-up were favorable, and there were no significant differences between both types. There was neither recurrence nor incomplete resection in any patient for both types. CONCLUSION: All patients, regardless of the TS-GCT type, achieved favorable outcomes after arthroscopic surgery; especially, the failure rate was 0%.

Intraoperative cone-beam computed tomography-guided curettage for osteoid osteoma.

Recently, cone-beam computed tomography (CBCT)-guided surgeries have been developed for bone and soft tissue tumors. The present study aimed to evaluate the efficacy of CBCT-guided curettage for osteoid osteoma. Our study population included 13 patients who underwent primary curettage for osteoid osteoma using intraoperative CBCT in a hybrid operating room between April 2019 and November 2022. We collected the following data: sex, age, follow-up period, symptom onset to time of surgery, tumor size and location, length of skin incision, operating time, radiation dose, recurrence, postoperative complications, and visual analog scale for pain during the last follow-up. There were 10 male and 3 female patients, and the mean age was 25.0 years (range, 9-49 years). The mean follow-up period was 10.6 months (range, 0.4-24.0 months). The locations of the tumors were the proximal femur in 6 patients, the acetabular region in 2 patients, and the ilium, tibial shaft, calcaneus, cuboid, and talus in 1 patient each. The mean time of symptoms onset to surgery was 18.7 months (range, 2.3-69.9 months). The mean maximum diameter of the tumor was 5.9 mm (range, 3.5-10.0 mm). The mean length of the skin incision was 2.2 cm (range, 1.5-3.5 cm). The mean operating time was 96.9 minutes (range, 64-157 minutes). The mean dose of radiation was 193.2 mGy (range, 16.3-484.0 mGy). No recurrences, postoperative complications, and reoperation were observed in this study. All the patients reported 0 mm on the visual analogue scale for pain on the last follow-up. CBCT-guided curettage for osteoid osteoma was minimally invasive and reliable. This procedure can be effective for the treatment of lesions found in deep locations such as the pelvic bone and proximal femur or an invisible lesion that cannot be detected by regular fluoroscopy.

The Combination of Methioninase and Ethionine Exploits Methionine Addiction to Selectively Eradicate Osteosarcoma Cells and Not Normal Cells and Synergistically Down-regulates the Expression of C-MYC.

BACKGROUND/AIM: The fundamental and general hallmark of cancer cells, methionine addiction, termed the Hoffman effect, is due to overuse of methionine for highly-increased transmethylation reactions. In the present study, we tested if the combination efficacy of recombinant methioninase (rMETase) and a methionine analogue, ethionine, could eradicate osteosarcoma cells and down-regulate the expression of c-MYC. MATERIALS AND METHODS: 143B osteosarcoma cells and Hs27 normal human fibroblasts were tested. The efficacy of rMETase alone and ethionine, alone and in their combination, on cell viability was determined with the WST-8 assay on 143B cells and Hs27 cells. c-MYC expression was examined with western immunoblotting and compared in 143B cells treated with/without rMETase, ethionine, or the combination of both rMETase and ethionine. RESULTS: 143B cells were more sensitive to both rMETase and ethionine than Hs 27 cells, with the following IC50s: rMETase (143B: 0.22 U/ml; Hs27: 0.82 U/ml); ethionine (143B: 0.24 mg/ml; Hs27: 0.42 mg/ml). The combination of rMETase and ethionine synergistically eradicated 143B cells, lowering the IC50 for ethionine 14-fold compared to ethionine alone (p<0.001). In contrast, Hs27 fibroblasts were relatively resistant to the combination. The expression of c-MYC was significantly down-regulated only by the combination of rMETase and ethionine in 143B cells (p<0.001). CONCLUSION: In the present study, we showed, for the first time, the synergistic combination efficacy of rMETase and ethionine on osteosarcoma cells in contrast to normal fibroblasts, which were relatively resistant. The combination of rMETase and ethionine down-regulated c-MYC expression in the cancer cells. The present results indicate the combination of rMETase and ethionine may reduce the malignancy of osteosarcoma cells and can be a potential future clinical strategy.

Denosumab administration for bone metastases from solid tumors: a retrospective cross-sectional study.

BACKGROUND: Little is known on how denosumab reduces skeletal-related events (SREs) by bone metastases from solid tumors. We sought to evaluate the effect of denosumab administration in patients with bone metastases from solid tumors. METHODS: Data of patients treated with denosumab were collected from electronic medical charts (n = 496). Eligible participants in this study were adult patients (age ≥ 18 years) with metastatic bone lesions from solid tumors treated with denosumab. SREs, surgical interventions, the spinal instability neoplastic score (SINS) for spinal region, and Mirels' score for the appendicular region were evaluated. To assess whether denosumab could prevent SREs and associated surgery, the SINS and Mirels' score were compared between patients with and without SREs. RESULTS: A total of 247 patients (median age, 65.5 years old; median follow-up period, 13 months) treated with denosumab for metastatic bone lesions from solid tumors were enrolled in this study. SREs occurred in 19 patients (7.7%). SREs occurred in 2 patients (0.8%) who took denosumab administration before SREs. Surgical interventions were undertaken in 14 patients (5.7%) (spinal and intradural lesions in five patients and appendicular lesions in nine patients). The mean SINS of patients without SREs compared to those with SREs were 7.5 points and 10.2 points, respectively. The mean Mirels' scores of non-SREs patients and those with SREs were 8.07 points and 10.7 points, respectively. Patients with SREs had significantly higher Mirels' score than non-SREs patients (p < 0.01). Patients with SREs had higher SINS than non-SREs patients (p = 0.09). CONCLUSIONS: SREs occurred in patients with higher SINS or Mirels' scores. Two patients suffered from SREs though they took denosumab administration before SREs. Appropriate management of denosumab for patients with bone metastasis is significant. Surgical interventions may be needed for patients who with higher SINS or Mirel's scores.

Management of Antithrombotic Drugs before Elective Spine Surgery: A Nationwide Web-Based Questionnaire Survey in Japan.

Introduction: The number of patients on antithrombotic drugs for coronary heart disease or cerebrovascular disease has been increasing with the aging of society. We occasionally need to decide whether to continue or discontinue antithrombotic drugs before spine surgery. The purpose of this study is to understand the current perioperative management of antithrombotic drugs before elective spine surgery in Japan. Methods: In 2021, members of the Japanese Society for Spine Surgery and Related Research (JSSR) were asked to complete a web-based questionnaire survey that included items concerning the respondents' surgical experience, their policy regarding discontinuation or continuation of antithrombotic drugs, their reasons for decisions concerning the management of antithrombotic drugs, and their experience of perioperative complications related to the continuation or discontinuation of these drugs. Results: A total of 1,181 spine surgeons returned completed questionnaires, giving a response rate of 32.0%. JSSR board-certified spine surgeons comprised 75.1% of the respondents. Depending on the management policy regarding antithrombotic drugs for each comorbidity, approximately 73% of respondents discontinued these drugs before elective spine surgery, and about 80% also discontinued anticoagulants. Only 4%-5% of respondents reported continuing antiplatelet drugs, and 2.5% reported continuing anticoagulants. Among the respondents who discontinued antiplatelet drugs, 20.4% reported having encountered cerebral infarction and 3.7% reported encountering myocardial infarction; among those who discontinued anticoagulants, 13.6% reported encountering cerebral embolism and 5.4% reported encountering pulmonary embolism. However, among the respondents who continued antiplatelet drugs and those who continued anticoagulants, 26.3% and 27.2%, respectively, encountered an unexpected increase in intraoperative bleeding, and 10.3% and 8.7%, respectively, encountered postoperative spinal epidural hematoma requiring emergency surgery. Conclusions: Our findings indicate that, in principle, >70% of JSSR members discontinue antithrombotic drugs before elective spine surgery. However, those with a discontinuation policy have encountered thrombotic complications, while those with a continuation policy have encountered hemorrhagic complications.

Long-lasting Limb Salvage After Malignant Femoral-Bone Tumor Resection Reconstructed With a Thin-mantle Titanium Stem Fixated With Cement.

BACKGROUND/AIM: The purpose of the present study was to review and report clinical outcomes of the Kyocera Modular Limb Salvage System (KMLS) using a thin-mantle titanium stem fixated with cement, for reconstruction after resection of malignant femoral-bone tumors. PATIENTS AND METHODS: Twenty consecutive patients who had undergone reconstruction using the KMLS with cemented thin-mantle titanium stem fixation between July 2010 and December 2019 at Ryukyu University Hospital were included. We retrospectively collected the following data: age, sex, follow-up period, tumor location, histological diagnosis, stem size, overall implant survival, radiolucency, postoperative complications, overall survival, and oncological survival. RESULTS: The median follow-up period was 63 months (range=10.7-261 months). The bone tumors were in the proximal part of the femur in 9 patients and in the distal part of the femur in 11 patients. The 5-year overall implant survival rate was 90.9% among surviving patients. A revision surgery was required for only one patient (5%), due to infection. Radiolucency, due to an instability of the implant, was observed in 7 out of 20 patients: 6 patients with distal femoral reconstruction, and 1 patient with proximal femoral reconstruction. However, none of the patients complained of any symptoms or required revision surgeries at the last follow-up. The 5-year overall patient-survival rate was 67.6%. CONCLUSION: The KMLS with cemented thin-mantle titanium stem fixation for femoral bone reconstruction after resection for bone malignancy resulted in long-term patient benefit.

Evidence of causality of low body mass index on risk of adolescent idiopathic scoliosis: a Mendelian randomization study.

Introduction: Adolescent idiopathic scoliosis (AIS) is a disorder with a three-dimensional spinal deformity and is a common disease affecting 1-5% of adolescents. AIS is also known as a complex disease involved in environmental and genetic factors. A relation between AIS and body mass index (BMI) has been epidemiologically and genetically suggested. However, the causal relationship between AIS and BMI remains to be elucidated. Material and methods: Mendelian randomization (MR) analysis was performed using summary statistics from genome-wide association studies (GWASs) of AIS (Japanese cohort, 5,327 cases, 73,884 controls; US cohort: 1,468 cases, 20,158 controls) and BMI (Biobank Japan: 173430 individual; meta-analysis of genetic investigation of anthropometric traits and UK Biobank: 806334 individuals; European Children cohort: 39620 individuals; Population Architecture using Genomics and Epidemiology: 49335 individuals). In MR analyses evaluating the effect of BMI on AIS, the association between BMI and AIS summary statistics was evaluated using the inverse-variance weighted (IVW) method, weighted median method, and Egger regression (MR-Egger) methods in Japanese. Results: Significant causality of genetically decreased BMI on risk of AIS was estimated: IVW method (Estimate (beta) [SE] = -0.56 [0.16], p = 1.8 × 10-3), weighted median method (beta = -0.56 [0.18], p = 8.5 × 10-3) and MR-Egger method (beta = -1.50 [0.43], p = 4.7 × 10-3), respectively. Consistent results were also observed when using the US AIS summary statistic in three MR methods; however, no significant causality was observed when evaluating the effect of AIS on BMI. Conclusions: Our Mendelian randomization analysis using large studies of AIS and GWAS for BMI summary statistics revealed that genetic variants contributing to low BMI have a causal effect on the onset of AIS. This result was consistent with those of epidemiological studies and would contribute to the early detection of AIS.

Imaging characteristics of tenosynovial giant cell tumors on 18F-fluorodeoxyglucose positron emission tomography/computed tomography: a retrospective observational study.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) is useful for assessing location, metastasis, staging, and recurrence of malignant tumors. Tenosynovial giant cell tumor (TSGCT) is a benign tumor; however, some studies have reported that TSGCTs have a high uptake of FDG. Few studies have reported on the detailed evaluation of TSGCT using 18F-FDG-PET/CT. The purpose of the current study is to evaluate the image characteristics and locations, particularly where possible, with or without, extra-articular invasion from TSGCT of the knee in 18F-FDG-PET/CT could occur. METHODS: We retrospectively reviewed the patients with TSGCT who were diagnosed pathologically either by biopsy or surgical specimen. Furthermore, we evaluated the difference of the maximum standardized uptake value (SUVmax) between diffused TSGCT with extra-articular invasion and TSGCT with intra-articular localization in the knee. RESULTS: The study consisted of 20 patients with TSGCT. The mean SUVmax of TSGCT was 12.0 ± 6.50. There were five patients with TSGCT arising in the knee with extra-articular invasion and six with TSGCT with intra-articular localization. The mean SUVmax of TSGCT with extra-articular invasion and those with intra-articular localization were 14.3 ± 6.00 and 5.94 ± 3.89, respectively. TSGCT with extra-articular invasion had significantly higher SUVmax than TSGCT with intra-articular localization (p < 0.05). CONCLUSIONS: TSGCT revealed high FDG uptake. Furthermore, SUVmax was higher in diffused TSGCT with extra-articular invasion than in intra-articular localized TSGCT; this may reflect its local aggressiveness.

Systematic Literature Review and Meta-Analysis on the Clinical Outcomes of Spine Surgeries in Patients with Concurrent Osteoporosis.

Background: Osteoporosis is common among elderly patients and can result in vertebral fractures requiring surgical treatment. This study assessed clinical outcomes associated with spinal surgery in patients with osteoporosis/osteopenia with an additional focus on Asian patients. Methods: A PRISMA-compliant systematic review and meta-analysis were conducted using the PubMed and ProQuest databases to identify articles published up to May 27, 2021, that included outcomes for patients with osteoporosis or osteopenia undergoing spinal surgery. Statistical analysis was conducted comparing rates of proximal junctional kyphosis (PJK)/proximal junctional failure (PJF), implant loosening, and revision surgery. A qualitative summary of Asian studies was also conducted. Results: A total of 16 studies comprising 133,086 patients were included; among the 15 studies reporting rates of osteoporosis/osteopenia, 12.1% (16,127/132,302) of patients overall and 38.0% (106/279) of Asian patients (n=4 studies) had osteoporosis/osteopenia. The risks of PJK/PJF (relative risk [RR]=1.89; 95% confidence interval [CI]=1.22-2.92, p=0.004), screw loosening (RR=2.59; 95% CI=1.67-4.01, p<0.0001), and revision surgery (RR=1.65; 95% CI=1.13-2.42, p=0.010) were higher in patients with poor bone quality compared with those with healthy bone. In the qualitative review of Asian studies, all studies found that osteoporosis increased the risk of complications and/or revision for spinal surgery patients. Conclusions: This systematic literature review and meta-analysis indicate that spinal surgery patients with compromised bone quality have more complications and higher healthcare utilization than those with normal bone quality. To our knowledge, this is the first study to focus on the pathophysiology and disease burden among Asian patients. Given the high rate of poor bone quality in this aging population, additional high-quality Asian studies, with uniform definitions and data reporting, are needed.

Precise and Facile Endotracheal Lung-tumor-implantation Mouse Model Visualized by GFP Expression.

BACKGROUND/AIM: In osteosarcoma, lung metastasis is a major cause of cancer-related death, as the 5-year survival rate for patients with metastases is approximately only 20-30%. To develop improved therapeutic strategies against lung-metastatic osteosarcoma, an experimental lung-tumor-implantation mouse model is needed for basic research. In the present study, we developed a precise and facile endotracheal lung-tumor-implantation technique. MATERIALS AND METHODS: For establishment of the lung-tumor-implantation mouse model of metastatic osteosarcoma, 5 mice were used. A 15-mm longitudinal incision was made in the center of the neck to expose the salivary glands. The salivary glands were then split, exposing the trachea covered by the sternohyoid muscles. The trachea was then clearly exposed by cutting the sternohyoid muscles longitudinally. A 22 G gavage needle was tilted slightly toward the left side of the mouse and inserted from the oral cavity into the bronchus, with confirmation of the position of the tip of the gavage needle visualized through the tracheal wall, followed by injection of 0.5% crystal violet to first confirm the accuracy of endotracheal injection in the lung. A 143B-GFP cell suspension (2.0×106 cells/50 µl PBS) was then injected endotracheally in other mice. RESULTS: The procedure, including anesthesia and suturing, took approximately 10 minutes. The left lobe of the lung, in which crystal violet was injected endotracheally, was stained in 3 out of 3 mice (100%). 143B-GFP-osteosarcoma tumors were detected with GFP fluorescence in the left lobe of the lung in 3 out of 4 mice (75%), 5 weeks after endotracheal injection. One mouse died 4 weeks after 143B-GFP-cell implantation. CONCLUSION: This novel technique of establishing tumors in the lung via endotracheal injection of cancer cells is precise and facile and can be used widely, since neither a surgical microscope nor X-ray imaging are needed.

Reconstructed bone fracture 28 years after hip rotationplasty for Ewing sarcoma: A case report.

Hip rotationplasty is a surgical method used to treat malignant tumors of the proximal femur. A 52-year-old woman, who underwent hip rotationplasty for Ewing sarcoma of the proximal left femur at the age of 24, fell and hit the left buttock. The patient was then admitted to the Department of Orthopedic Surgery, Graduate School of Medicine, University of the Ryukyus. Radiography and computed tomography (CT) revealed a comminuted fracture of the reconstructed bone distally. The patient underwent open reduction and internal fixation (ORIF) and external fixator. External fixation was removed 1 month after the surgery. At two years after surgery, at the latest follow-up, bone union was confirmed by 3-dimensional CT. The combination of ORIF and temporal external fixation was effective for the reconstructed bone fractures after hip rotationplasty.

Relationship between the morphology of osteophytes and cartilage lesions in anterior ankle impingement in athletes: a cross-sectional study.

BACKGROUND: The present study aimed to describe the frequency and severity of tram-track lesions in anterior ankle impingement in athletes and to evaluate the association between osteophyte morphology and severity of tram-track lesions, the distinctive cartilage lesions associated with tibial osteophytes in anterior ankle impingement syndrome. METHODS: We evaluated 34 athletes who underwent arthroscopic osteophyte resection for anterior ankle impingement between January 2017 and March 2021. RESULTS: We found tram-track lesions in 26 athletes (76.5%). Arthroscopic findings revealed the distribution of the International Cartilage Repair Society grades of tram-track lesions (grade 0, eight; grade 1, seven; grade 2, ten; grade 3, nine; grade 4, zero). These findings indicate that athletes with anterior ankle impingement syndrome may have more severe cartilage lesions than non-athletes. There was a positive correlation between the International Cartilage Repair Society grade and osteophyte size (r = 0.393, p = 0.021). We divided athletes into two groups according to the presence or absence of osteophyte protrusion into the joint space. Osteophyte protrusion was present in 14 athletes (41.2%). All athletes in the protrusion-type group had tram-track lesions; seven (50%) had International Cartilage Repair Society grade 3. The protrusion-type group's International Cartilage Repair Society grade was significantly higher than that of the non-protrusion-type group (p = 0.008). The osteophyte sizes in the two groups were not significantly different (p = 0.341). CONCLUSIONS: Based on these findings, osteophyte protrusion should be assessed when an indication of arthroscopic treatment for anterior ankle impingement syndrome is considered, particularly in athletes.

Secure paediatric pelvic fracture external fixation using an intraoperative support device.

Secure fixation by inserting a half-pin into the iliac crest as a pelvic external fixator is important. However, the thickness of the iliac bone depends on its location and this makes it difficult to insert a half-pin accurately. The iliac crest is especially narrow in the paediatric pelvis, making it difficult to insert the half-pin accurately compared with an adult pelvis. A case of pelvic external fixation is described for a paediatric pelvic fracture in this report, in which preoperative planning for half-pin insertion was performed accurately using a preoperative three-dimensional CT based on an intraoperative support device that uses the functional pelvic plane as a reference.

Progressive scoliosis associated with microphthalmia with limb anomalies: A case report.

RATIONALE: Microphthalmia with limb anomalies is a rare, autosomal recessive, multiple congenital anomaly syndrome. Patients with this syndrome particularly present with monocular or bilateral anophthalmia/microphthalmia and distal limb anomalies. However, details regarding associated spinal deformities have not been fully elucidated. PATIENT CONCERNS: A 12-year-old girl initially presented with progressive scoliosis, who was previously diagnosed with microphthalmia with limb anomalies. However, 4 years after the initial visit, the scoliosis deformity gradually progressed. The patient and family requested the surgical treatment to preserve standing/sitting balance. DIAGNOSES: She was diagnosed with microphthalmia with limb anomalies and progressive scoliosis. INTERVENTIONS: A posterior corrective fusion surgery (including a pelvic fusion) was performed to prevent future standing/sitting imbalance. OUTCOMES: Significant improvement of spinal deformity was observed, with no adverse events. LESSONS: This report demonstrated a case of progressive scoliosis associated with microphthalmia with limb anomalies. A posterior corrective spinal fusion was effective to preserve standing/sitting balance. To the best of our knowledge, this is the first report of surgical treatment of progressive scoliosis associated with microphthalmia with limb anomalies.

Oncogenes and Methionine Addiction of Cancer: Role of c-MYC.

BACKGROUND/AIM: Methionine addiction is a general and fundamental hallmark of cancer cells, termed the Hoffman effect. Previously Vanhamme and Szpirer showed that methionine addiction could be induced by transfection of the activated HRAS1 gene to a normal cell line. In the present study, we investigated the role of the c-MYC oncogene in methionine addiction of cancer, by comparison of c-Myc expression and malignancy of methionine-addicted osteosarcoma cells and rare methionine-independent revertants, derived from the methionine-addicted cells. MATERIALS AND METHODS: Methionine-independent revertant 143B osteosarcoma cells (143B-R) were derived from methionine-addicted parental 143B osteosarcoma cells (143B-P), by continuous culture in medium depleted of methionine by recombinant methioninase. To compare in vitro malignancy of methionine-addicted parental cells and methionine-independent revertant cells, the following experiments were performed: for 143B-P and 143B-R cells, cell proliferation capacity was measured with a cell-counting assay, and colony-formation capacity was determined on plastic and in soft agar, all in methionine-containing Dulbecco's Modified Eagle's Medium (DMEM). Tumor growth was measured in orthotopic xenograft nude-mouse models, to compare in vivo malignancy of 143B-P and 143B-R cells. c-MYC expression was examined with western immunoblotting and compared in 143B-P and 143B-R cells. RESULTS: 143B-R cells had reduced cell proliferation capacity, compared to 143B-P cells, in methionine-containing medium (p=0.003). 143B-R cells had reduced colony formation capacity on plastic (p=0.003) and in soft agar, compared to 143B-P cells in methionine-containing medium. 143B-R cells had reduced tumor growth in orthotopic xenograft nude-mouse models, compared to 143B-P cells, (p=0.002). These results demonstrate that 143B-R methionine-independent revertant cells lost malignancy. Expression of c-MYC was reduced in 143B-R methionine-independent revertant osteosarcoma cells, compared to 143B-P cells, (p=0.0007). CONCLUSION: The present study demonstrated that c-MYC expression is linked to malignancy and methionine addiction of cancer cells. The present study on c-MYC, and the previous study on HRAS1, suggest that oncogenes may play a role in methionine addiction, which is a hallmark of all cancers, as well as in malignancy.