Prognostic value of CAF marker expression in the intratumoral and marginal areas of soft tissue sarcoma.

INTRODUCTION: The tumor microenvironment of sarcomas has not been studied in detail; in particular, little is known about cancer-associated fibroblasts (CAFs). Sarcoma cells are difficult to distinguish from CAFs, either histomorphologically or immunohistochemically. METHODS: We scored expression of individual CAF markers (fibroblast activating protein (FAP), CD10, and podoplanin) in the intratumoral and marginal areas of 133 sarcomas. We also examined the association between these markers, as well as the number of CD163-positive macrophages (i.e., tumor-associated macrophages), and clinical outcome. RESULTS: In all cases, the log-rank test revealed that those with high marker scores and macrophage counts (except for marginal CD10+ CAFs) showed significantly worse disease-free survival (DFS). Grade 2/3 cases with high CAF scores (excluding the marginal FAP and CD10 scores) showed significantly worse DFS, whereas those with high intratumoral FAP/CD10 and marginal podoplanin scores showed significantly worse metastasis-free survival (MFS), and those with a high intratumoral CD10 score showed significantly worse local recurrence-free survival (LFS). Multivariate analysis identified intratumoral CD10/podoplanin scores and marginal FAP/podoplanin scores as independent prognostic factors for DFS, intratumoral FAP/CD10 and marginal FAP/podoplanin/CD163-positive macrophage scores as independent prognostic factors for MFS, and the intratumoral podoplanin score as an independent prognostic factor for LFS. There was a weak-to-moderate correlation between each score and CD163-positive macrophage counts. CONCLUSION: Patients with high CAF marker expression in the intratumoral and marginal areas have a poorer outcome.

Coefficient of variation of T2-weighted MRI may predict the prognosis of malignant peripheral nerve sheath tumor.

BACKGROUND: We investigated whether non-enhancement MRI features, including measurement of the heterogeneity of the tumor with MR T2 imaging by calculating coefficient of variation (CV) values, were associated with the prognosis of non-metastatic malignant peripheral nerve sheath tumors (MPNST). METHODS: This retrospective study included 42 patients with MPNST who had undergone surgical resection (mean age, 50 years ± 21; 20 male participants). Non-enhancement MR images were evaluated for signal intensity heterogeneity on T1- and T2-weighted imaging, tumor margin definition on T1- and T2-weighted imaging, peritumoral edema on T2-weight imaging, and CV. We measured the signal intensities of MR T2-weighted images and calculated the corresponding CV values. CV is defined as the ratio of the standard deviation to the mean. The associations between factors and overall survival (OS) were investigated via the Kaplan-Meier method with log-rank tests and the Cox proportional hazards model. RESULTS: The mean CV value of MR T2 images was 0.2299 ± 0.1339 (standard deviation) (range, 0.0381-0.8053). Applying receiver operating characteristics analysis, the optimal cut-off level for CV value was 0.137. This cut-off CV value was used for its stratification into high and low CV values. At multivariate survival analysis, a high CV value (hazard ratio = 3.63; 95% confidence interval = 1.16-16.0; p = 0.047) was identified as an independent predictor of OS. CONCLUSION: The CV value of the signal intensity of heterogenous MPNSTs MR T2-weighted images is an independent predictor of patients' OS.

The Prognostic Significance of Surgical Treatment for Excessive Elderly Soft Tissue Sarcoma Patients Over 90 Years Old: A Clinicopathological Study of 16 Cases.

OBJECTIVES: The incidence of soft tissue sarcomas (STS) among older patients is increasing. Although surgical treatment of elderly patients with STS has been reported to improve their prognosis, most of these studies included patients with STS aged < 85 years. This study aimed to analyze the clinical features and prognostic factors of STS in elderly patients aged ≥ 90 years. SUBJECT AND METHODS: We retrospectively identified patients aged ≥ 90 years with STS who were treated at our two hospitals between 1994 and 2022. Data on clinical information and detailed assessments were collected. We evaluated the features and factors affecting the prognosis of patients with older-extremity STS. In addition, we compared the clinical courses and results of patients treated with surgery and radiotherapy for primary tumors. RESULTS: Among 454 patients with STS, 16 were aged ≥ 90 years. Kaplan-Meier curves for overall survival showed a significantly poorer prognosis in patients who did not receive surgical treatment (p = 0.0348) and those who received radiotherapy (p = 0.0070). Moreover, we investigated the difference in prognosis between surgical treatment and radiotherapy, excluding two cases with distant metastasis at initial diagnosis and one case with no treatment. Kaplan-Meier curves for overall survival showed a significantly better prognosis in patients who underwent surgical treatment (p = 0.0161). Univariate analysis revealed that only primary tumor size was a significant predictor of poor prognosis (p = 0.0426). CONCLUSION: In patients with STS aged ≥ 90 years old, aggressive surgical treatment may improve the prognosis more than radiotherapy.

Factors Affecting the Second Complete Atypical Femoral Fracture after the First Atypical Fracture.

OBJECTIVES: Atypical femoral fracture (AFF) is an atypical low-energy subtrochanteric and diaphyseal femoral fracture. Even if bone fusion is achieved in patients with AFF, the risk of AFF in the contralateral femur must be considered. This study aimed to investigate the factors affecting complete AFF in the contralateral femur and conservatively treated incomplete AFF. SUBJECT AND METHODS: Radiographs of 111 femurs in 104 AFF cases were examined, and the femurs were classified as follows: 85 contralateral femurs with complete AFF; 18 contralateral femurs with incomplete AFF; 8 femurs with incomplete AFF without surgical treatment. Various patients' clinical data were collected, and we investigated the factors affecting the second complete AFF. RESULTS: Complete fractures occurred in 10 (9.7%) of 103 femurs without incomplete AFF at the first visit and in 3 (37.5%) of 8 femurs with incomplete AFF. The Kaplan-Meier curve revealed that lateral cortical bone thickening and thigh pain were associated with significantly poorer prognoses (p = 0.026 and p = 0.013, respectively). Multivariate analyses revealed that eldecalcitol usage after AFF onset (p = 0.0094) and previous use of bisphosphonate or denosumab (p = 0.0126) were protective factors for second complete AFF and that the presence of thigh pain (p = 0.0134) was a risk factor for second complete AFF. CONCLUSIONS: Eldecalcitol administration after bone union of first AFF may prevent AFF recurrence. In addition, painful incomplete AFF has a high risk of developing a complete fracture.

Effects of bisphosphonates and treadmill exercise on bone and kidney in adenine-induced chronic kidney disease rats.

INTRODUCTION: The increasing prevalence of osteoporosis and chronic kidney disease (CKD) due to the aging of society has highlighted the need for development of effective treatments for elderly patients. This study examined whether the combination of treadmill exercise therapy and alendronate (ALN) can improve bone mineral density (BMD) and bone strength without worsening renal function in adenine-induced CKD model rats. MATERIALS AND METHODS: 8-week-old male Wistar rats (n = 70) were divided into experimental groups based on the treatment protocol, i.e., non-CKD (control), vehicle only (CKD), ALN only, exercise only, and combined ALN plus exercise. A 0.75% adenine diet was used to induce CKD. Groups were killed at either 20 or 30 weeks of age. Comprehensive assessments included serum and urine biochemistry tests, renal histology, bone histomorphometry, BMD measurement, micro-computed tomography examinations, and biomechanical testing. RESULTS: Blood biochemistry tests, urine analyses and histological evaluations of the kidney demonstrated that ALN treatment did not worsen renal function or kidney fibrosis in moderate-stage CKD model rats. Both ALN and treadmill exercise significantly suppressed bone resorption (p < 0.05-p < 0.01). Moreover, ALN monotherapy and combined ALN and treadmill exercise significantly improved BMD of the lumbar spine and femur, bone microstructure, and trabecular bone strength (p < 0.05-p < 0.01). Treadmill exercise was also shown to decrease cortical porosity at the mid-diaphysis of the femur and improve kidney fibrosis. CONCLUSION: The combination of ALN and treadmill exercise is effective in improving BMD, the microstructure of trabecular and cortical bone, and bone strength, without compromising renal function in adenine-induced CKD model rats.

Comparison of the Continuation Rate of Twice-Weekly and Weekly Teriparatide Administration in a Rural Area.

Teriparatide plays an important role in the treatment of patients with severe osteoporosis; however, it is meaningless if patients cannot continue. In recent years, the use of a twice-weekly auto-injector teriparatide preparation has become possible. However, its continuation rate and the factors affecting it have not been adequately investigated. Therefore, this study aimed to examine the continuation rate of twice-weekly teriparatide and the factors affecting it. This retrospective study included 143 patients who were administered teriparatide weekly (65 patients) or twice-weekly (78 patients) in a rural hospital. Patient information, such as age, the distance between the hospital and home, family structure, past osteoporosis treatment and fracture, adverse events, and period of teriparatide continuation, were collected. We compared the differences in continuation rates between the twice-weekly and the weekly groups using the Kaplan-Meier curves, and we examined factors influencing teriparatide discontinuation using multivariate analyses. The 12- and 24-month continuation rates of twice-weekly administration of teriparatide were 79.5% and 61%, respectively. The twice-weekly group showed a significantly higher continuation rate (P < 0.0001). The multivariate analyses showed that older age and adverse events were identified as risk factors negatively influencing teriparatide continuation (P = 0.0237 and P < 0.0001, respectively). On the other hand, twice-weekly teriparatide was shown to reduce the risk of discontinuation (P = 0.0043). The twice-weekly teriparatide has a considerably higher continuation rate than the weekly teriparatide. Weekly preparation, older age, and adverse event were identified as risk factors negatively influencing teriparatide continuation.

Effects of teriparatide and low-intensity aerobic exercise on osteopenia in type 2 diabetes mellitus rats.

INTRODUCTION: In patients with type 2 diabetes mellitus (T2DM), bone fragility increases fracture risk. Teriparatide (TPTD) improves bone strength, and exercise therapy suppresses blood glucose levels in T2DM. In this study, the combined effects of TPTD and exercise therapy on trabecular and cortical bone were examined in advanced T2DM model rats. MATERIALS AND METHODS: Thirty-week-old Otsuka Long-Evans Tokushima Fatty rats were divided into four groups (n = 9-10 in each group at two time points): Cont group (vehicle-treated control), TPTD group (TPTD 30 µg/kg injected subcutaneously, 3 times/week), Exe group (treadmill exercise, 10 m/min, 60 min/day, 5 times/week), and Comb group (TPTD-treated and treadmill exercise combined). Five and 10 weeks after treatment, bone mineral density (BMD), bone strength, and bone micro-architecture were measured. RESULTS: TPTD and combined treatment significantly increased BMDs of the lumbar spine and femur compared to the Cont group (p < 0.05 to p < 0.01). In the three-point bending test of the femur, only combined treatment increased the maximum load at 5 weeks compared with the Cont and Exe groups (p < 0.01). In the compression test of the distal femoral metaphysis, both TPTD and combined treatment increased the trabecular bone strength compared with the Cont and Exe groups (p < 0.05 to p < 0.01). Although TPTD and combined treatment improved the micro-architecture of trabecular bone (p < 0.05 to p < 0.01), only combined treatment improved the micro-structures of cortical bone from 5 weeks of treatment (p < 0.05 to p < 0.01). CONCLUSION: The combination of TPTD and treadmill exercise increased BMD and trabecular and cortical bone strength of the femur with improved micro-architecture in T2DM model rats.

Non-ossifying fibromas and fibrous cortical defects around the knee - an epidemiologic survey in a Japanese pediatric population.

BACKGROUND: The aim of the present study was to evaluate the prevalence of non-ossifying fibroma (NOF) and fibrous cortical defect (FCD) in a Japanese pediatric population and the association between the lesion size and pain. METHODS: This retrospective study, conducted across 10 Japanese institutions, included patients aged 5-15 years who had undergone standard antero-posterior and lateral view radiography of the knee. Using these radiographs, we diagnosed the lesion as a NOF or FCD. Patient demographics, including age, sex, the size and location of the NOF, and chief complaint were recorded. The lesion size was determined using radiographs. Student's t-test was used to compare the associations between the lesion size and spontaneous pain. RESULTS: A total of 6222 subjects (3567 boys and 2455 girls) were included in this study. The number of NOF and FCD cases was 143 and 437, respectively, and the prevalence of NOF and FCD was 2.3% and 7.0%, respectively. The average size of NOF and FCD was 22.1 mm (range: 4-102 mm) and 13.2 mm (range: 5-21 mm), respectively. Three patients (2.1%) had pathological fractures due to NOF. Of the 140 NOFs and 437 FCDs, we obtained complaints from the medical records of 126 and 393 patients, respectively. The number of patients with spontaneous pain or other problems with NOF was 68 (54%) and 58 (46%), respectively, that of patients with FCD was 195 (50%) and 198 (50%) patients, respectively. The lesion size was not associated with spontaneous pain in either lesion (p = 0.67 and p = 0.27, respectively). CONCLUSION: The prevalence of NOF and FCD around the knee was lower than that reported in previous studies. The prevalence of NOF increased and that of FCD decreased with advancing age. In both lesions, the lesion size may not be associated with pain.

Successful Treatment of Atypical Femoral Fracture with Bowed Femur Using Contralateral Intramedullary Nail Combined with Early Daily Teriparatide.

We report a case of atypical femoral fracture achieving early fracture union with combination therapy comprising contralateral nail and immediate teriparatide injection. Fracture union of atypical fractures is often delayed due to bowing deformity and bone metabolic disorders. Combination treatment that takes both problems into consideration represents a useful treatment option for atypical femoral fracture.

Teriparatide and exercise improve bone, skeletal muscle, and fat parameters in ovariectomized and tail-suspended rats.

INTRODUCTION: Although teriparatide (TPTD) and exercise may improve osteoporosis, muscle atrophy, and fat metabolism during ageing, the effects of treatment with a combination of TPTD and exercise on these factors remain unclear. Therefore, this study examined the effects of TPTD and exercise on bone, skeletal muscle, and fat in ovariectomized and tail-suspended rats. MATERIALS AND METHODS: Seven-month-old female Wistar rats were ovariectomized and subjected to tail suspension. The rats were then randomized into one of the following four groups (n = 20/group) after 4 weeks: control group, treated with TPTD vehicle and no exercise; TPTD group (30 µg/kg TPTD, 3 days/week); Exercise group (treadmill at 12 m/min, 60 min/day, 5 days/week); and Combined group treated with TPTD and treadmill exercise. After 1 and 8 weeks of treatment, bone, skeletal muscle, and fat tissue parameters were evaluated. RESULTS: TPTD improved bone mineral density (BMD), bone structure, bone strength at the femoral metaphysis, and the percentage of skeletal muscle mass, and decreased the percentage of fat mass and the adipose volume in the bone marrow. Treadmill exercise increased BMD, bone strength of cancellous bone, and the percentage of skeletal muscle mass, and decreased the percentage of fat mass as seen on dual-energy X-ray absorptiometry. Furthermore, combined treatment significantly affected BMD, bone structure, and bone strength of cortical bone at the femoral diaphysis. CONCLUSION: TPTD or treadmill exercise improved bone, skeletal muscle, and fat mass. Combination therapy with TPTD and exercise had synergistic effects on BMD, structure, and bone strength in ovariectomized, tail-suspended rats.

Tumor Lysis Syndrome due to Eribulin Administration for Metastatic Undifferentiated Pleomorphic Sarcoma of the Buttock.

Tumor lysis syndrome (TLS) is a complication of cancer treatment that requires urgent intervention. It is extremely rare in the treatment of soft tissue sarcoma (STS) of the limbs or trunk, and there are currently no reports of TLS occurrence from eribulin therapy. We report the case of a 78-year-old woman with an undiffer-entiated pleomorphic sarcoma on the right buttock. We initiated chemotherapy with intravenous eribulin mesylate. Deterioration of renal function, mild hyperkalemia, hyperuricemia, hypocalcemia, and hyperphos-phatemia were confirmed on examination, suggesting the presence of TLS. We present an extremely rare case of TLS from eribulin for STS.

Deep Angiomyxoma of the Thigh That Is Difficult to Diagnose: A Case Report and Literature Review.

We present an extremely rare case of deep angiomyxoma (DAM) in the thigh that was misdiagnosed as desmoid-type fibromatosis. A 40-year-old Japanese woman presented with a mass on the left thigh. The histological diagnosis by needle biopsy was desmoid-type fibromatosis; the tumor grew slowly and was resected 4 years later. The histological diagnosis from the resected tumor was DAM. As of 16 months post-surgery, the patient has not noticed any local recurrence. Although DAM in a lower extremity is extremely rare, clinicians must be aware of its possible occurrence in areas relatively close to the pelvis.

Guideline-based Treatment of Glucocorticoid-induced Osteoporosis in Patients with Rheumatoid Arthritis: A Retrospective Study with the AORA Registry.

Glucocorticoid-induced osteoporosis (GIOP) is one of the side effects associated with glucocorticoid (GC) therapy. In 2014, the Japanese Society for Bone and Mineral Research (JSBMR) provided new guidelines for the management and treatment of GIOP. The aim of the present study was to clarify the prevalence of patients with rheumatoid arthritis (RA) requiring treatment according to the new guidelines and to identify risk factors associated with lack of treatment in these patients. Patients in the 2018 Akita Orthopedic group on Rheumatoid Arthritis (AORA) database were enrolled. Of 2,234 patients with RA in the database, 683 (30.6%) met the 2014 JSBMR guideline treatment criteria, and 480 (70.3%) had been treated. The untreated group included a larger number of males, younger patients, and patients treated in clinics rather than hospital (p<0.001, p=0.015, and p<0.001, respectively). Multivariate analyses found that male sex, younger age, and clinic-based RA care were significant risk factors associated with lack of treatment (p<0.001, p=0.013, and p<0.001, respectively). Thus, male sex, younger age, and clinic-based care were identified as risk factors.

Effectiveness of Ilizarov external fixation in elderly patients with pilon fractures.

BACKGROUND: Pilon fractures are associated with soft tissue complications such as skin necrosis, and deep infections have been reported very often. This study retrospectively compared the treatment effects of Ilizarov external fixation and of internal fixation methods in elderly patients with pilon fractures. METHODS: A total of 37 patients >60 years old with pilon fractures (AO classification type 43) were investigated. Patients were treated either with internal fixation (n = 15) or Ilizarov external fixation (n = 22). The patients' mean age was 74.2 (range, 60-78) years in the internal fixation group and 76.1 (range, 60-82) years in the Ilizarov external fixation group. Many patients in the internal fixation group received toe-touch to 1/3 partial weight-bearing at 2-4 weeks postoperatively and full weight-bearing by 6-8 weeks postoperatively. Many patients in the Ilizarov external fixation group received partial weight-bearing (as tolerated) 1 day postoperatively, 1/2 partial weight-bearing at 2 weeks postoperatively, and full weight-bearing at 4 weeks postoperatively. RESULTS: The mean duration of hospitalization was 79.1 ± 30.1 days for the internal fixation group and 29.1 ± 18.8 days for the Ilizarov external fixation group (p < 0.05). Bone mineral density (T-score) was 2.6 ± 0.7 for the internal fixation group and 3.6 ± 1.2 for the Ilizarov external fixation group (p < 0.05). The incidence of skin disorders that required additional surgical treatment was 33.3% (5/15 patients) in the internal fixation group and 0% (0/22 patients) in the Ilizarov external fixation group (p < 0.05). CONCLUSIONS: In elderly patients with periarticular fractures of the ankle, those who underwent Ilizarov external fixation had a shorter duration of hospitalization and fewer complications than those who underwent internal fixation.

Evaluation of the Nature and Etiologies of Risk Factors for Diaphyseal Atypical Femoral Fractures.

OBJECTIVES: Differences in mechanisms of subtrochanteric and diaphyseal atypical femoral fractures (AFFs) are speculated in studies that analyzed differences in the patients' background. However, the etiologies of each type of AFF have not been studied in detail. This study aimed to investigate the nature and etiologies of the risk factors for diaphyseal AFFs. MATERIALS AND METHODS: Eighty consecutive Japanese patients with 91 diaphyseal AFFs (AFF group) and 110 age-matched women with osteoporosis (non-AFF control group) were included. Their clinical data were compared; factors affecting AFFs were investigated, and the etiologies of the risk factors for diaphyseal AFFs were examined. RESULTS: Multivariate analysis revealed that femoral serrated changes, bisphosphonate or denosumab usage, and lateral and anterior femoral curvatures were risk factors for diaphyseal AFFs (p < 0.0011, p = 0.0137, and p < 0.0001, respectively). Multivariate analyses revealed that serrated changes and low serum 25(OH)D levels affected the lateral curvature (p = 0.0088 and 0.0205, respectively), while serrated changes affected the anterior curvature (p = 0.0006), each significantly affected the femoral curvature. High serum calcium (Ca) levels, lateral femoral curvature, and anterior femoral curvature were predictors of serrated changes (p = 0.0146, 0.0002, and 0.0098, respectively). CONCLUSION: Risk factors for diaphyseal AFFs were bone resorption inhibitor usage, a strong femoral curvature, and serrated changes. Low serum 25(OH)D levels and serrated changes are risk factors for lateral curvature, while a high serum Ca level is a risk factor for serrated changes.

The value of the black fiber sign on T1-weighted images for predicting stability of desmoid fibromatosis managed conservatively.

OBJECTIVES: It is challenging to know at the first which patients with desmoid fibromatosis (DF) are better suited to conservative or aggressive treatment. To investigate whether the low signal intensity bundles on T1- or T2-weighted images (WI), termed the "black fiber sign (BFS)," can predict non-progressive behavior in the conservative approach. METHODS: This retrospective study included 59 patients with primary DF managed with wait-and-see approach from 2005 to 2018 and serial MR images were analyzed. Three observers blinded to the patient information verified the presence or absence of BFS on baseline T1 or T2WI. The likelihood of progression-free survival (PFS) after ascertaining the presence or absence of the BFS was estimated using the Kaplan-Meier method and analyzed with the log-rank test. RESULTS: PFS was significantly higher in cases with BFS than without BFS on T1WI (p < 0.01), but there was no significant difference in PFS between cases with and without BFS on T2WI. Multivariable Cox proportional hazards analysis revealed that the absence of BFS on T1WI was a high-risk factor for progression (hazard ratio, 14.9; p < 0.01). Drastic tumor regression was apparent with significantly increased low-signal area in cases with BFS on T1WI. Intra- and interobserver reliabilities of BFS on T1WI were in almost-perfect agreement (κ > 0.8). CONCLUSION: Our retrospective observational data support that presence of BFS in baseline MRI may be a predictor for progression-free survival of DF. BFS on T1WI is easily identifiable and can be utilized clinically in patients with DF. KEY POINTS: • We proposed a new imaging marker for prediction of desmoid fibromatosis progression. • The absence of black fiber sign predicted a high risk of disease progression.

Factors affecting continuation of weekly teriparatide administration in rural areas.

INTRODUCTION: Although teriparatide plays an important role in the treatment of patients with severe osteoporosis, it is meaningless if patients cannot continue. There have been few reports of studies evaluating factors affecting the continuation rate of weekly teriparatide; moreover, no study has investigated the relationship between the distance to travel to the hospital and continuation rate. Therefore, we examined the continuation rate of weekly teriparatide and factors that affect this rate. MATERIALS AND METHODS: This retrospective study included 73 patients who were administered weekly teriparatide in a rural hospital. Patient information, including the age, sex, distance between the hospital and home, family structure, place of introduction, reason for the start of teriparatide administration, past osteoporosis treatment and fracture, side effects, and period of teriparatide continuation, was collected. We examined factors influencing weekly teriparatide continuation. RESULTS: The continuation rate of weekly teriparatide was 22.7%. The Kaplan-Meier curves for the two groups regarding the place of introduction and side effects showed significant differences (P = 0.0158 and P = 0.0309, respectively). In the multivariate analyses to investigate factors associated with teriparatide continuation, an older age, starting administration while hospitalized, and side effects were identified as risk factors negatively influencing continuation (P = 0.0280, P = 0.0222, and P = 0.0095, respectively). On the other hand, the number of family members and distance between our hospital and home did not affect teriparatide continuation. CONCLUSION: An older age, starting administration while hospitalized, and side effects were identified as risk factors negatively influencing teriparatide continuation.

Effects of bazedoxifene and low-intensity aerobic exercise on bone and fat parameters in ovariectomized rats.

INTRODUCTION: Postmenopausal osteoporosis and dyslipidemia are well-known skeletal and metabolic changes in middle-aged women. We investigated the effects of combined treatments with a selective estrogen receptor modulator (SERM) and exercise on bone and fat parameters in ovariectomized (OVX) rats. MATERIALS AND METHODS: Sixteen-week-old female Sprague-Dawley rats underwent bilateral ovariectomy, and rats were randomized to BZA (bazedoxifene at 0.3 mg/kg/day), Exe (treadmill exercise at 12-15 m/min, 60 min/day, 5 days/week), Comb (BZA and Exe), and Cont (control treated with vehicle and no exercise) groups 8 weeks after ovariectomy. After 4 or 8 weeks of treatment, bone mineral density (BMD) of the total femur and lumbar spine and whole-body percentage fat mass were determined by dual-energy X-ray absorptiometry, and mechanical testing of the femoral shaft, and bone and fat histomorphometric analyses of the proximal tibia were performed. RESULTS: Treadmill exercise had decreased bone marrow adipocytes from 4 weeks of treatment and whole-body percentage fat mass at 8 weeks. BZA increased BMD at the lumbar spine and decreased the whole-body percentage fat mass from 4 weeks and bone marrow adipocytes at 8 weeks. Combination therapy increased BMD for the lumbar spine and decreased bone marrow adipocytes and whole-body percentage fat mass from 4 weeks. CONCLUSION: Combination therapy with BZA and exercise appears effective to improve bone and fat parameters in OVX rats.

Effectiveness of circular external fixator in periprosthetic fractures around the knee.

BACKGROUND: The incidence of periprosthetic fractures after total joint arthroplasty (TJA) is rising due to an increasing number of TJAs performed annually and the growing elderly population. In many elderly patients with periprosthetic fractures, the bone strength is lowered due to the deterioration of bone quality and a decrease in bone quantity; rigid fixation of the fracture is difficult. It is a challenging operation for orthopedic surgeons. The usefulness of circular external fixation for periprosthetic fractures has been reported in several case studies. The aim of this study was to investigate the rate of union and complications associated with circular external fixation in periprosthetic fractures around the knee. METHODS: We included 19 patients with periprosthetic femur and tibial fractures who underwent osteosynthesis using a circular external fixator and had at least 2 years of follow-up. All patients had comorbidities and high risks associated with anesthesia. Tourniquets were not used in any of the patients. There were no cases in which the skin incision was placed, and the closed reduction technique was used in all cases. RESULTS: A 100% union rate was achieved with no serious complications. All fractures healed after a mean time of 14.3 ± 5.2 weeks (range, 8-38 weeks). The walking ability was the same level as before the injury in 13 cases. DISCUSSION: There are many comorbidities associated with periprosthetic fractures in elderly patients. Double-plate or revision surgery were largely invasive and had high risks associated with anesthesia. Circular external fixation is a feasible and effective treatment option because it provides stable fixation, prompt postoperative mobilization, and has no major complications, especially in elderly patients who are treated for periprosthetic fractures. CONCLUSION: Circular external fixation is a safe and reliable method for periprosthetic fractures around the knee in elderly patients. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Effectiveness of distal tibial osteotomy with distraction arthroplasty in varus ankle osteoarthritis.

BACKGROUND: In highly active older individuals, end-stage ankle osteoarthritis has traditionally been treated using tibiotalar arthrodesis, which provides considerable pain relief. However, there is a loss of ankle joint movement and a risk of future arthrosis in the adjacent joints. Distraction arthroplasty is a simple method that allows joint cartilage repair; however, the results are currently mixed, with some reports showing improved pain scores and others showing no improvement. Distal tibial osteotomy (DTO) without fibular osteotomy is a type of joint preservation surgery that has garnered attention in recent years. However, to our knowledge, there are no reports on DTO with joint distraction using a circular external fixator. Therefore, the purpose of this study was to examine the effect of DTO with joint distraction using a circular external fixator for treating ankle osteoarthritis. METHODS: A total of 21 patients with medial ankle arthritis were examined. Arthroscopic synovectomy and a microfracture procedure were performed, followed by angled osteotomy and correction of the distal tibia; the ankle joint was then stabilized after its condition improved. An external fixator was used in all patients, and joint distraction of approximately 5.8 mm was performed. All patients were allowed full weight-bearing walking immediately after surgery. RESULTS: The anteroposterior and lateral mortise angle during weight-bearing, talar tilt angle, and anterior translation of the talus on ankle stress radiography were improved significantly (P < 0.05). Signal changes on magnetic resonance imaging also improved in all patients. Visual analog scale and American Orthopedic Foot & Ankle Society scores improved significantly (P < 0.05), and no severe complications were observed. CONCLUSION: DTO with joint distraction may be useful as a joint-preserving surgery for medial ankle osteoarthritis in older patients with high levels of physical activity. LEVEL OF EVIDENCE: Level IV, retrospective case series.