Development of a New Focal Mouse Model of Bone Metastasis in Renal Cell Carcinoma.

BACKGROUND/AIM: Developing animal models of bone metastasis in renal cell carcinoma (RCC) is challenging as immunodeficient mice are required. The aim of this study was to develop a simple immune model of RCC bone metastasis. MATERIALS AND METHODS: RENCA tumor cells were injected into the right femurs of BALB/c mice. Sixty mice were grouped into each twenty-mouse group according to the tumor cell concentration, and the presence or absence and extent of bone metastasis in the total length of the femur were compared using hematoxylin and eosin staining of the excised tissues. RESULTS: Bone metastasis was significantly higher in the high concentration group than in the other groups (p<0.05), with 10 mice developing bone metastasis at two weeks and nine mice developing bone metastasis at three weeks. The extent of bone metastasis was significantly greater in the high concentration group than in the other groups (p<0.05). Multiple logistic regression analysis was performed to examine the factors influencing bone metastasis, and only the high concentration was a significant factor (p<0.05). CONCLUSION: We developed a normal immunity mouse model of local bone metastasis from RCC. This model could prove valuable for research into the treatment of bone metastases in RCC.

The Effects of Switch Therapy in Osteoporosis Treatment after Romosozumab after Comparing with Prior Treatment.

Rationale. Although romosozumab is one of the most effective treatments for osteoporosis by increasing bone mineral density in the lumbar spine and femur and recommended for denosumab as switch therapy, these effects regarding its prior treatment have not yet been evaluated clearly. This study focused on the effects of switch therapy from romosozumab to denosumab in regard to prior treatment of osteoporosis including bone mineral density and bone turnover marker and other related factors. Patient Concerns. 15 osteoporotic patients were assigned to the naïve group, 15 were assigned to the teriparatide group, and 10 were assigned to the bisphosphonate group. Interventions. Patients who were treated as outpatients for osteoporosis with romosozumab for 1 year and switched to denosumab between 2020 and 2022 at our hospital were examined. Our hospital registry included 40 osteoporotic patients who were over 65 years of age with bone mineral density (bone mineral density): T score <-2.5 standard deviations (SDs) and fracture assessment tool (FRAX) score >20%. Outcomes. The naïve group had the highest increase in LS BMD among these three groups during switch therapy from romosozumab to denosumab, while there were no significant differences about adverse drug events and serum Ca concentration among them. There was no incidence of fracture. Conclusion. These findings indicate that the effects of osteoporotic treatment of switch therapy from romosozumab to denosumab were likely to affect prior treatment of osteoporosis.

A nationwide multicenter study of the cost effectiveness of five leading drugs for pharmacological management of cervicobrachial symptoms.

BACKGROUND: Cervicobrachial pain frequently affects the quality of life (QOL) of the general public and has a significant economic impact on the health care systems of various countries. There are a number of treatment options for this disease, including widely-used drug therapy, but the effectiveness of each option is indeterminate, and there have been no published cost-effectiveness analysis studies so far. This prospective observational study aimed to examine the cost-effectiveness of drug treatment for cervicobrachial symptoms. METHODS: A 6-month medication regimen for each of five frequently-prescribed drugs for cervicobrachial symptoms was administered to 322 patients at 24 centers in Japan. Outcome measures, including of the EuroQol Group 5D, Short Form-8, and Visual Analog Scale (VAS), were investigated at baseline and every month thereafter. Incremental cost-effectiveness ratios (ICERs) of the drug cost to quality-adjusted life years (QALYs) were calculated. A stratified analysis of patient characteristics was also performed to identify baseline factors potentially affecting cost-effectiveness. RESULTS: The ICER of entire drug treatment for cervicobrachial symptoms was 7,491,640 yen. Compared with the reference willingness-to-pay, the ICER was assumed to not be cost-effective. A certain number of QALYs were gained during the first 3 months after the treatment intervention, but almost no QALYs were gained during the following 3 months. Stratified analysis showed that cost-effectiveness was extremely low for patients with high baseline VAS and high QOL. CONCLUSIONS: The available medications for cervicobrachial symptoms did not have excellent cost-effectiveness. Although a certain number of QALYs were gained during the first 3 months after medication, no QALYs were gained in the latter half of the study period, suggesting that it is not advisable to continue the medication needlessly. LEVEL OF EVIDENCE: II, prospective cohort study.

A Comparison of Hidden Blood Loss Between Multilevel Posterior Lumbar Interbody Fusion and Lateral Lumbar Interbody Fusion in Adult Spinal Deformity Patients.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: This study aimed to compare transfusion and blood loss volumes, particularly hidden blood loss volume, in adult spinal deformity patients undergoing lateral lumbar interbody fusion (LLIF) and posterior lumbar interbody fusion (PLIF). Corrective surgery for adults with spinal deformity patients can be performed via the traditional posterior approach (PLIF) or minimally invasive lateral approach (LLIF). LLIF is associated with longer or comparable operation times and lower intraoperative blood loss. However, hidden blood loss has not been compared between the two procedures. METHODS: We compared hidden blood loss and other blood loss volumes, transfusion volume, operation time, and radiographic surgical outcomes between LLIF patients (n = 71) and PLIF patients (n = 33) who underwent surgery in our institution from September 2011 to June 2018. All patients provided informed consent in accordance with the Declaration of Helsinki. Institutional ethics committee conducted this study approval was obtained. RESULTS: Transfusion volume and intraoperative and total blood loss volumes were significantly higher in the PLIF group. Operation time and HBL did not significantly differ. The hidden blood loss-to-intraoperative blood loss ratio was significantly higher in the LLIF group (113% vs 60%; P = .004). Radiographic measures of outcome were significantly better after surgery than before in both groups. CONCLUSIONS: Although intraoperative blood loss was less with LLIF than PLIF, HBL was similar between the approaches. Patients undergoing LLIF should be followed closely for postoperative anemia even if intraoperative blood loss is low.

Two Cases of Degenerative Cervical Spondylotic Myelopathy in Adults with Athetoid and Dystonic Cerebral Palsy.

BACKGROUND Patients with athetoid and dystonic cerebral palsy (ADCP) may develop degenerative changes in the cervical spine that can aggravate their neurological symptoms in adulthood. This report is of 2 cases of ADCP associated with degenerative cervical spondylotic myelopathy in a 39-year-old woman and a 52-year-old man, requiring different surgical treatments. CASE REPORT Case 1. The patient was a 39-year-old woman who had fallen down 7 years before surgery and had since been walking with a cane. Her gait disturbance had worsened in the 2 years prior to surgery, and numbness in her upper limbs appeared. In the year before surgery, spasticity and numbness in the lower limbs worsened, and fine motor impairment also appeared. Because of mild involuntary movements of the neck, cervical laminoplasty from C3 to C6 was performed, and her symptoms remained stable until the last follow-up 4.5 years after surgery. Case 2. The patient was a 52-year-old man who had fallen down 7 years before surgery, resulting in transient limb weakness. In the year before surgery, he had developed fine motor impairment. He subsequently developed gait disturbance and requested cervical surgery. Because of involuntary movements involving the neck and trunk, he underwent cervical posterior fusion from C2 to T1. Six months after surgery, the gait disturbance had improved. CONCLUSIONS This report describes 2 adults with a history of ADCP since birth and highlights that degenerative changes of the cervical spine can occur at a relatively early age in adulthood, requiring an individualized approach to management.

Comparative efficacy of ultrasound guidance and fluoroscopy or computed tomography guidance in spinal nerve injections: a systematic review and meta-analysis.

PURPOSE: Spinal nerve injections have traditionally been performed under fluoroscopic (FL) and computed tomography (CT) guidance. Recently, ultrasound (US)-guided procedures have provided an alternative guidance approach that does not expose the patient and operator to radiation. The aim of this study was to compare the efficacy and safety of US-guided spinal nerve injections compared with FL- or CT-guided spinal nerve injections. METHODS: MEDLINE, Cochrane Library, EMBASE, international clinical trials registry platform (ICTRP) and ClinicalTrials.gov database searches for inclusion until February 2023 were independently performed by two authors using predefined criteria. Randomized controlled trials (RCTs) were included. Primary outcomes were change in pain score (numeric rating scale or visual analogue scale) and major adverse events. Secondary outcomes were procedure time, change in functional disability score and minor adverse events. Meta-analysis was performed using random-effect model. We evaluated the certainty of evidence based on the Grading of Recommendations, Assessment and Development (GRADE) approach. RESULTS: Eight RCTs involving 962 patients were included. There might be little to no difference in the mean score of the pain change between the US-guided methods and the FL- or CT-guided injections (standard mean difference -0.06; 95% confidence interval [CI] -0.26 to 0.15). US guidance probably reduced major adverse events (0.7% [3/433] and 6.5% [28/433], respectively), reduced procedure time (mean difference -4.19 min; 95% CI -5.09 to -3.30), and probably reduced minor adverse events (2.1% [9/433] and 4.2% [18/433], respectively) compared with FL or CT guidance. There was probably little to no difference in the change in functional disability score with either method. CONCLUSION: US-guided spinal nerve injections remained effective and reduced adverse events compared with conventional FL- or CT-guided spinal nerve injections. Further RCTs are required to verify our results. STUDY REGISTRATION: Open Science Forum (Available from: https://osf.io/vt92w/ ).

Neurological Analysis Based on the Terminal End of the Spinal Cord and the Narrowest Level of Injured Spine in Thoracolumbar Spinal Injuries.

This study aimed to clarify neurological differences among the epiconus, conus medullaris, and cauda equina syndromes. Eighty-seven patients who underwent surgery for acute thoracolumbar spinal injuries were assessed. We defined the epiconus as the region from the terminal end of the spinal cord to the proximal 1.0 to 2.25 vertebral bodies, the conus medullaris as the region proximal to < 1.0 vertebral bodies, and the cauda equina as the distal part of the nerve roots originating from the spinal cord. On the basis of the distance from the terminal end of the spinal cord to the narrowest level of the spinal canal, the narrowest levels were ordered as follows: the epiconus followed by the conus medullaris and cauda equina. The narrowest levels were the epiconus in 22 patients, conus medullaris in 37 patients, and cauda equina in 25 patients. On admission, significantly more patients had a narrowed epiconus of Frankel grades A-C than a narrowed cauda equina. At the final follow-up, there were no significant differences in neurological recovery among those with epiconus, conus medullaris, or cauda equina syndrome. Anatomically classifying the narrowest lesion is useful for clarifying the differences and similarities among these three syndromes.

Preoperative factors affecting the two-year postoperative patient-reported outcome in single-level lumbar grade I degenerative spondylolisthesis.

Background: The choice of operative method for lumbar spinal stenosis with Meyerding grade I degenerative spondylolisthesis remains controversial. The purpose of this study was to identify the preoperative factors affecting the 2-year postoperative patient-reported outcome in Meyerding grade I degenerative spondylolisthesis. Methods: Seventy-two consecutive patients who had minimally invasive decompression alone (D group; 28) or with fusion (DF group; 44) were enrolled. The parameters investigated were the Japanese Orthopaedic Association back pain evaluation questionnaire as patient-reported assessment, and L4 slippage (L4S), lumbar lordosis (LL), and lumbar axis sacral distance (LASD) as an index of sagittal alignment for radiological evaluation. Data collected prospectively at 2 years postoperatively were examined by statistical analysis. Results: Sixty-two cases (D group; 25, DF group; 37) were finally evaluated. In multiple logistic regression analysis, preoperative L4S and LASD were extracted as significant preoperative factors affecting the 2-year postoperative outcome. Patients with preoperative L4S of 6 mm or more have a lower rate of improvement in lumbar spine dysfunction due to low back pain (risk ratio=0.188, p=.043). Patients with a preoperative LASD of 30 mm or more have a higher rate of improvement in lumbar dysfunction due to low back pain (risk ratio=11.48, p=.021). The results of multiple logistic analysis by operative method showed that there was a higher rate of improvement in lumbar spine dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more in DF group (risk ratio=172.028, p=.01). Conclusions: Preoperative L4S and LASD were extracted as significant preoperative factors affecting patient-reported outcomes at 2 years postoperatively. Multiple logistic analyses by the operative method suggested that DF may be advantageous in improving lumbar dysfunction due to low back pain in patients with preoperative LASD of 30 mm or more.

Effects of Soft Tissue Sarcoma and Doxorubicin on Bone Metabolism in Mice.

BACKGROUND/AIM: This study aimed to evaluate the effects of doxorubicin (Dox) on bone microstructure and metabolism in a mouse model of soft tissue sarcoma. MATERIALS AND METHODS: CCRF S-180II cells (2-4×105 cells/0.2 ml) were injected subcutaneously into the back of mice. The mice were divided into four groups according to tumor and treatment status and were reared and sacrificed after 2 or 4 weeks. Micro-computed tomography (CT) was performed to calculate the architecture of the femoral bone. The proximal tibia was double stained with tartrate-resistant acid phosphatase (TRACP) and alkaline phosphatase (ALP), and bone morphometry was performed. RESULTS: Trabecular bone mass was significantly reduced in the Sarcoma and Sarcoma+Dox groups. Cortical bone thickness was reduced in the DOX group, with a stronger effect observed in the Sarcoma+Dox group. In bone morphometry, osteoclast number at the bone surface (Oc.N/BS) was significantly lower in the Dox, Sarcoma, and Sarcoma+Dox groups than in the Control group at 2 weeks. The osteoblast surface at the bone surface (Ob.S/BS) was significantly lower in the Dox and Sarcoma groups than in the Control group at 2 weeks. At 4 weeks, the differences were smaller for both Oc.N/BS and Ob.S/BS. CONCLUSION: The use of doxorubicin alone worsened the cortical bone structure; however, the presence of both soft-tissue sarcoma and doxorubicin use worsened both cortical and trabecular bone structures from an early stage.

Skip Fusion With Sacral-Alar-Iliac Screw Fixation for Pelvic Ring and Lumbar Fractures: A Case Report.

Pelvic ring fractures are associated with high-energy trauma and high mortality owing to critical blood loss and concomitant injuries. If there is a concurrent lumbar fracture, the postoperative range of motion will be limited owing to the increased fusion range. Here, we report a case in which skip fusion with sacral-alar-iliac screw fixation was effective as a minimally invasive procedure for treating pelvic ring and lumbar fractures.

Relationship between Intervertebral Disc Compression Force and Sagittal Spinopelvic Lower Limb Alignment in Elderly Women in Standing Position with Patient-Specific Whole Body Musculoskeletal Model.

The intervertebral disc loading based on compensated standing posture in patients with adult spinal deformity remains unclear. We analyzed the relationship between sagittal alignment and disc compression force (Fm). In 14 elderly women, the alignment of the sagittal spinopelvic and lower extremities was measured. Fm was calculated using the Anybody Modeling System. Patients were divided into low sagittal vertical axis (SVA) and high SVA groups. Comparisons between the two groups were performed and the relationship between the Fm and each parameter was examined using Spearman's correlation coefficient (r). The mean lumbar Fm in the high SVA group was 67.6%; significantly higher than that in the low SVA group (p = 0.046). There was a negative correlation between cervical Fm with T1 slope (r = -0.589, p = 0.034) and lumbar Fm with lumbar lordosis (r = -0.566, p = 0.035). Lumbar Fm was positively correlated with center of gravity-SVA (r = 0.615, p = 0.029), T1 slope (r = 0.613, p = 0.026), and SVA (r = 0.612, p = 0.020). The results suggested sagittal malalignment increased the load on the thoracolumbar and lower lumbar discs and was associated with cervical disc loading.

A prospective analysis of concentration of 25-OHD between northern and southern district in Japan in year-round study.

Although osteoporotic patients have already been recognized as having a low-volume vitamin D status, the concentration of active vitamin D precursor has not been studied in detail. This trial aimed to clarify the concentration of 25-hydroxyvitamin D (25-OHD), which is a natural type of vitamin D and compare between 2 separate areas in Japan. To compare and clarify the concentration of 25-OHD between 2 separate areas, Japanese patients who were diagnosed as having osteoporosis based on bone mineral density were studied. We analyzed 2 different hospitals' patients whose residence is separated into a northern district (Akita city: north latitude 39" 43') and a southern district (Shizuoka city: north latitude 34" 58'). Both of them have completely different daylight hours. Three-hundred sixty eight patients (174 in Akita, 194 in Shizuoka) were enrolled in this trial to compare the differences of concentration of 25-OHD by Welch's t t-test. There were significant differences in the concentration of 25-OHD and age between them. Akita patients were significantly higher than that of Shizuoka patients despite Shizuoka having much daylight hours of Akita. In conclusion, there might be no relationship between the concentration of 25 OHD and exposure to sunlight.

Intravascular Administration of Acridine Orange and Zoledronate in a Bone Metastasis Model of Breast Cancer.

BACKGROUND/AIM: This study evaluated the effect of haematogenous administration of acridine orange (AO) alone and in combination with zoledronate (ZOL) on bone metastases. MATERIALS AND METHODS: E0771 cells (1.0×105 cells/10 µl) were injected directly into the right femur of female mice. The mice were divided into five groups according to treatment (drugs and irradiation) and were reared and sacrificed after 6 weeks. Micro-computed tomography (µCT) was performed to calculate the destruction rate of the femur bone. We measured tumour weight and volume at sacrifice and performed terminal deoxynucleotidyl transferase dUTP Nick-End Labelling staining of tumours. RESULTS: At 4 weeks, the bone destruction rate was lower in the AO+ZOL group than in the radiation group. At 6 weeks, the AO+ZOL group had a lower bone destruction rate than the control and radiation groups; the ZOL group had a lower rate than the radiation group. The AO and AO+ZOL groups had suppressed tumour weight and volume compared to the control and radiation groups. The number of extraosseous apoptotic cells was higher in the AO+ZOL group than in all other groups except the AO group. CONCLUSION: In a model of local bone metastasis of breast cancer, haematogenous administration of AO reduced tumour size and more so when combined with ZOL.

Earlier appearance of Risser sign on ultrasound versus radiograph in adolescent idiopathic scoliosis.

Objective: The usefulness of ultrasound in the detailed assessment of the Risser sign is still unclear. The purpose of this study was to analyze the usefulness of ultrasound for determining the Risser sign compared with that determined by conventional radiography by each Risser grade. Materials and Methods: Eighty-eight iliac crests from 44 adolescent patients who visited the scoliosis clinic with Risser grades 0-4 were evaluated. The ultrasound probe was placed vertically on the iliac crest and the point where iliac apophysis ossification ended was marked. The length of ossification relative to the length of the iliac crest was calculated. Results: Agreement between radiographic and ultrasound images were found in 58/86 iliac crests (67%). Kappa value was 0.565. Agreement between the two methods with regard to Risser grade was 53% for grade 0, 43% for grade 1, 47% for grade 2, 88% for grade 3, and 90% for grade 4. With additional analysis by integrating grades into two groups, the agreement rate was 47.7% and the Kappa value was 0.288 in the grade 0-2 group, and 88% and 0.703 in grades 3-4 group, respectively. In cases of disagreements, 93% of the iliac crests were judged as having higher Risser grades by ultrasound than by radiograph. Conclusion: Risser sign evaluation by ultrasound demonstrated a higher agreement rate in grades 3 and 4, whereas less agreement was found in grades 0-2. In the majority of cases with disagreement, ultrasound showed a higher grade than radiography, suggesting that ossification can be detected earlier with ultrasound than with radiography.

Degenerative Lumbar Spondylolisthesis Patients With Movement-related Low Back Pain Have Less Postoperative Satisfaction After Decompression Alone.

STUDY DESIGN: Retrospective analysis of prospectively collected multicenter observational data. OBJECTIVE: The aim was to examine the preoperative factors affecting postoperative satisfaction following posterior lumbar interbody fusion (PLIF) and microendoscopic muscle-preserving interlaminar decompression (ME-MILD) in patients with degenerative lumbar spondylolisthesis (DLS). SUMMARY OF BACKGROUND DATA: The technique involved in DLS surgery may either be decompression alone or decompression-fixation. Poor performance may occur after either of these surgical treatments. The author hypothesized that evaluating the correlation between preoperative quality of life and postoperative performance would aid in determining the optimal procedure. MATERIALS AND METHODS: This study included 138 patients who underwent surgery for 1-level mild DLS. The authors performed PLIF for 79 patients and ME-MILD for 59 patients. When the satisfaction subscale of the Zurich Claudication Questionnaire exceeded 2 points, postoperative satisfaction was considered poor. The clinical characteristics were investigated. Responses to preoperative health-related quality of life questionnaires, such as the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), short form-36 health survey (SF-36), and visual analog scale, were compared between the satisfied and unsatisfied groups. RESULTS: In the PLIF group, no endogenous factors influenced postoperative satisfaction. The ME-MILD cohort's satisfied and unsatisfied patients differed significantly in terms of preoperative lumbar spine dysfunction ( P <0.001) items of the JOABPEQ, role physical ( P =0.03), and role emotional ( P =0.03) items of the SF-36. A strong correlation ( r =-0.609 P =0.015) was found between preoperative lumbar spine dysfunction and postoperative satisfaction. CONCLUSIONS: In the ME-MILD group, preoperative lumbar spine function was correlated with postoperative satisfaction. Decompression alone may be ineffective in cases with decreased lumbar spine function prior to surgery. The degree of low back pain on movement should be considered before selecting the surgical method. LEVEL OF EVIDENCE: 3.

The relationship between chronic kidney disease and denosumab-induced hypocalcemia in high-age osteoporotic patients.

PURPOSE: A few studies have reported the safety of the treatment of elderly osteoporotic patients with chronic kidney disease (CKD) and the possibility of hypocalcemia. The aim of the present study was to examine the relationship between the incidence of hypocalcemia and the CKD stage in elderly osteoporotic patients treated with denosumab. MATERIALS AND METHODS: This study was designed as a parallel-group comparison study between the denosumab-associated hypocalcemia (DAH) groups: the concentration of serum calcium was under 8.6 mg/dl and the normal calcium (NC) groups: the concentration of serum calcium was over 8.6 mg/dl. Fifty-two subjects over 70 years old were enrolled in this study, with 16 patients classified into the DAH group and 36 patients assigned to the NC group. All patients were further classified into two subgroups according to their age, into an around 75 years group to clarify the relevance of old age and an around 85 years group and also into a mild CKD group and a moderate CKD group by based on estimated glomerular filtration (eGFR). Serum calcium concentration, tartrate-resistant acid phosphatase (TRACP-5b), and type 1 procollagen N terminal propeptide (P1NP) were measured, and adverse drug reactions were evaluated. RESULTS: The eGFR and serum calcium were significantly lower in the DAH group than in the NC group in the starting phase. Moreover, TRACP-5b was significantly higher in the DAH group than in the NC group in the starting phase. There were no significant differences in P1NP. The incidence of hypocalcemia was significantly higher in the around 85 groups than in the around 75 groups. The frequency of hypocalcemia was also significantly higher in the severe CKD group than in the mild CKD group. CONCLUSION: Advanced age combined with low eGFR and low serum Ca status appear to be associated with the incidence of hypocalcemia when using denosumab for the treatment of osteoporosis.

Chronic atlantoaxial rotatory fixation with neurofibromatosis type I: A case report.

BACKGROUND: Atlantoaxial rotatory fixation (AARF) can be caused by infection, rheumatoid arthritis, surgery of head and neck, and congenital diseases. Type 1 neurofibromatosis (NF-1) is often associated with various musculoskeletal diseases, but few reports have described AARF with NF-1. Here, we report the success of a closed reduction and halo fixation utilized to treat chronic AARF with NF-1 in a 7-year-old female. CASE DESCRIPTION: A 7-year-old female with NF-1 presented with a 2-month history of torticollis and neck pain. C2 facet deformity had previously been identified on computed tomography (CT) before the onset of neck pain. Cervical radiography and CT showed AARF classified Fielding's Type I and Ishii's Grade II. Following 2 weeks of cervical traction, a closed reduction was followed by halo fixation that was utilized for 2 months. The patient fully recovered cervical range of motion following halo vest removal 4 months later. Further, the follow-up CT documented a normal atlantoaxial joint despite residual C2 facet deformity. In addition, no recurrence was evident 2 years later. CONCLUSION: Halo fixation for chronic AARF with NF-1 proved effective. C2 facet deformity associated with NF-1 might have contributed to the onset of AARF.

Development of New Mouse Breast Cancer Model of Local Bone Metastasis and Verification Using Bisphosphonates.

BACKGROUND/AIM: Local tumor injection models require complicated procedures. The purpose was to establish a simple local bone metastasis model using normal mice, and to study the usefulness of the model with bisphosphonates (BP). MATERIALS AND METHODS: This study used a versatile C57BL/6 mouse model and E0771 cells. Tumor cells were injected into the right femur. Mice were divided into groups depending on the concentration of cells injected and the use of BP or not. The degree of bone destruction between the different conditions was compared using micro-computed tomography (µCT). RESULTS: Bone destruction was confirmed in four mice in the high-concentration group at 3 weeks, and in all other mice at 4 and 6 weeks. At 6 weeks post-injection, bone destruction was significantly suppressed in the BP group (p<0.05). CONCLUSION: We created a breast cancer mouse model of local bone metastasis. Zoledronate showed the same usefulness as in previous models. It may be an effective model for evaluating treatments for bone metastasis.

Impact of a Specialized Outpatient Clinic on Bone Metastasis and Its Burden on Spine Surgeons.

BACKGROUND/AIM: It is important to perform early intervention on bone metastases using multidisciplinary approaches, however it is difficult to hold frequent meetings between patients and clinicians. We aimed to evaluate the usefulness of a specialized outpatient clinic on bone metastasis, instead of the multidisciplinary approach currently in practice. PATIENTS AND METHODS: We included 31 patients with vertebral metastases of various carcinomas, undergoing surgical treatment by spine surgeons. We divided the patients into two groups before and after their visit to the specialized outpatient clinic (pre and post groups), and compared their clinical characteristics. RESULTS: The post group demonstrated a longer period from consulting the spine surgeon to the surgery than the pre group (p=0.0129). A multivariate logistic regression analysis revealed that the period from spine surgeon consultation to surgery was significantly associated with a specialized outpatient clinic visit (p=0.0460). CONCLUSION: Specialized outpatient clinics on bone metastasis could possibly reduce the burden on spinal surgeons.