The Impact of Reduced Skeletal Muscle Mass on Patients with Knee Osteoarthritis.

Although several studies have suggested a possible association between sarcopenia and knee osteoarthritis (OA) in the elderly, there remains no definitive evidence. Recently, however, the serum creatinine/cystatin C ratio (sarcopenia index: SI) was reported to correlate with skeletal muscle mass. The present retrospective study therefore investigated the impact of reduced skeletal muscle mass on advanced knee OA using SI. In 55 individuals scheduled for knee osteotomy or knee arthroplasty, correlations between SI and patient-reported outcomes such as the Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Oxford Knee Score (OKS) were explored. Significant associations were found between SI and the KSS functional activity score (ß=0.37; p=0.022), KOOS subscale for activities of daily living (ß=0.42; p=0.0096), and OKS (ß=0.42; p=0.0095). This study underscores the role of reduced muscle mass in functional outcomes and introduces SI as a valuable marker for assessing muscle loss in knee OA patients.

Unicompartmental Knee Arthroplasty for Osteoarthritis Eliminates Lateral Thrust: Associations between Lateral Thrust Detected by Inertial Measurement Units and Clinical Outcomes.

The purpose of this study was to investigate the relationship between clinical outcomes and lateral thrust before and after unicompartmental knee arthroplasty (UKA) using inertial measurement sensor units. Eleven knees were evaluated with gait analysis. The varus angular velocity was used to evaluate lateral thrust. The femorotibial angle (FTA) and hip-knee-ankle angle (HKA) were used to evaluate lower-limb alignment, and the Oxford Knee Score (OKS) and Japanese Orthopaedic Association Score (JOA) were used to evaluate clinical outcomes. The mean pre-UKA peak varus velocity was 37.1 ± 9.8°/s, and that for post-UKA was 28.8 ± 9.1°/s (p = 0.00003), such that instabilities clearly improved. Assuming the definition of lateral thrust is when the varus angular velocity is more than 28.1°/s, 81.8% of patients had lateral thrust preoperatively, but this decreased to 55.6% postoperatively, such that the symptoms and objective findings improved. Both OKS and JOA improved after surgery. In addition, HKA was -7.9° preoperatively and -5.8° postoperatively (p = 0.024), and FTA was 181.4° preoperatively and 178.4° postoperatively (p = 0.012). There was a positive correlation between postoperative JOA and FTA, indicating that changes in postoperative alignment affected clinical outcomes. This study quantitatively evaluated the disappearance of lateral thrust by UKA, and it found that the stability can be achieved by UKA for unstable knees with lateral thrust.

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.

Preoperative inspiratory muscle weakness as a risk factor of postoperative pulmonary complications in patients with esophageal cancer.

OBJECTIVE: We examined whether preoperative inspiratory muscle weakness (IMW) is a risk factor for postoperative pulmonary complications (PPCs) in patients with esophageal cancer who underwent subtotal esophagectomy. METHODS: This single-center retrospective cohort study enrolled patients with esophageal cancer who underwent a scheduled subtotal esophagectomy between June 2020 and May 2022. Maximal inspiratory pressure (MIP) was measured as inspiratory muscle strength using a respiratory dynamometer, and we defined IMW as MIP < 80% of the predicted value. Our primary outcome comprised overall PPCs. We investigated the relationship between IMW and PPCs using the Bayesian logistic regression model. RESULTS: After exclusion, 72 patients were included in this study. IMW was identified in 26 patients (36%), and PPCs developed in 28 patients (39%). Among patients with IMW, 15 (58%) developed PPCs. Preoperative IMW was associated with PPCs (mean odds ratio [OR]: 3.58; 95% credible interval [95% CrI]: 1.29, 9.73) in the unweighted model. A similar association was observed in the weighted model adjusted for preoperative and intraoperative contributing factors (mean OR: 4.15; 95% CrI: 2.04, 8.45). CONCLUSIONS: Preoperative IMW was associated with PPCs in patients with esophageal cancer who underwent subtotal esophagectomy. This association remained after adjusting for preoperative and intraoperative contributing factors.

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.

Association of the Bioimpedance Phase Angle and Quality of Life in Postmenopausal Osteoporosis.

OBJECTIVES: Osteoporosis patients with fragility fractures and vertebral deformities have impaired quality of life (QOL). The phase angle, an index calculated from bioelectrical impedance analysis (BIA) measurements, has been reported to be related to clinical outcomes, mortality, and QOL in various diseases. We aimed to investigate the relationship between the phase angle and QOL in patients with postmenopausal osteoporosis. METHODS: 81 female patients treated for postmenopausal osteoporosis from September 2019 to March 2020 underwent measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry, body composition by BIA, and QOL by the 36-item Short-Form Health Survey (SF-36). RESULTS: The phase angle showed significant positive correlations with physical functioning (r = 0.270, p = 0.015) and physical component summary (PCS) (r = 0.251, p = 0.024) of the SF-36. The phase angle showed significant positive correlations with appendicular skeletal muscle mass index (ASMI) (r = 0.456, p < 0.001), lumbar spine BMD (r = 0.241, p = 0.030), and femoral neck BMD (r = 0.26, p = 0.021) and a significant negative correlation with age (r = -0.526, p < 0.001). Multiple regression analysis of the factors potentially associated with SF-36 PCS showed that the phase angle (r = 7.506, p = 0.012) was a significant contributor to PCS (R2 = 0.184). CONCLUSION: The phase angle in postmenopausal osteoporotic patients was significantly related to QOL after adjusting for age, BMI, ASMI, and BMD. As the phase angle is a parameter that can be measured easily and noninvasively, it might be a useful aid for QOL assessment in osteoporotic patients.

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.

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.

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.

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.

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.

Impact of vitamin C on teriparatide treatment in the improvement of bone mineral density, strength, and quality in vitamin C-deficient rats.

Age-related decreases in serum levels of vitamin C (VC) may negatively affect the efficacy of anti-osteoporotic pharmacotherapy. The purpose of this study was to evaluate the effects of VC and teriparatide (TPTD) on bone mineral density (BMD), strength, and quality in VC-deficient osteogenic disorder Shionogi (ODS) rats. Six-month-old female ODS rats were divided into an untreated ODS control group, a VC group, a TPTD group, and a VC + TPTD group, based on the administration of VC and TPTD (n = 10 each). VC was given as 2.0 mg/ml supplemented water. TPTD was administered subcutaneously once a week at 30 µg/kg body weight. After 12 weeks of treatment, BMDs of the femur and lumbar spine, bone strengths of the femoral diaphysis and metaphysis, and cancellous bone quality of proximal tibiae as estimated by Fourier transform infrared spectroscopy (FTIR) were compared between groups. Compared to the ODS control group, the VC group showed significantly higher total femoral BMD, but the TPTD group showed significantly higher femoral and lumbar spinal BMD, maximum load of femoral metaphysis, and hydroxyapatite (HA) crystallinity by FTIR (p < 0.05). In addition to the increases shown in the TPTD group, the VC + TPTD group also showed significantly higher stiffness of the femoral diaphysis and breaking energy of the femoral metaphysis compared to the ODS control group (p < 0.05). These results indicated that TPTD alone increased cancellous/cortical BMD and cancellous bone strength with improvement of HA crystallinity in ODS rats, but addition of VC supplementation further improved cortical bone strength.

An epidemiological study of traumatic spinal cord injuries in the fastest aging area in Japan.

STUDY DESIGN: Retrospective epidemiological study. OBJECTIVE: To investigate the epidemiology of traumatic spinal cord injury (TSCI) in the fastest aging area in Japan. SETTING: Hospitals in Akita Prefecture, Japan. Akita Prefecture has the highest ratio of people aged 65 or older in Japan (30.4% in 2012 and 34.6% in 2016). METHODS: Patients with acute TSCI who required hospital treatment between 2012 and 2016 were included. The incidence of TSCI, cause, level, skeletal injury, and Frankel grade were investigated. RESULTS: The mean annual incidence of TSCI excluding Frankel E was 86 per million (range 86-104 per million) during the 5-year study period, with a mean age of 65.9 years (male, 75.1%) and patients in their 60s as the largest age group. Cervical injury was seen in 89.8%, and cervical TSCI without skeletal injury was seen in 65.5%. Frankel D was the most common neurological deficit (53.5%). The most common cause was falls on level surfaces (32.1%), followed by low falls (21.6%) and road traffic accidents (15.6%). CONCLUSIONS: Recent incidence and characteristics of TSCI in the fastest aging society in Japan are presented. The incidence of incomplete cervical TSCI and falls on level surfaces appear to be increasing.

Intradural extramedullary tumor in the stenotic cervical spine resected through open-door laminoplasty with hydroxyapatite spacers: report of two cases.

BACKGROUND: Safe excision of spinal cord tumors depends on sufficient visualization of the tumor and surrounding structures. In patients with spinal cord tumor adjacent to a stenotic spinal canal, extensive bony decompression proximal and distal to the tumor should be considered for safer excision of the tumor. Extensive wide laminectomy is one choice for such cases, but postoperative problems such as kyphotic deformity remain a concern. CASE PRESENTATION: A 76-year-old man and a 60-year-old woman presented with symptomatic intradural extramedullary spinal cord tumors in the cervical spine. Both patients showed a combination of spondylotic changes in the cervical spine and stenotic condition at the level of the tumor. Both tumors were successfully resected through open-door laminoplasty with hydroxyapatite (HA) spacers, with the tumor located on the side of the laminoplasty. Histological diagnosis was schwannoma for both tumors. HA spacers completely bonded to the host bone and did not interfere with postoperative magnetic resonance imaging (MRI) of the inside of the spinal canal. Cervical spine alignment was maintained at the final follow-up of 6 years in both cases. CONCLUSION: Laminoplasty with HA spacers enabled successful tumor extirpation, reliable MRI follow-up after surgery, and maintenance of normal cervical spine alignment. Laminoplasty with HA spacers represents a good option for the treatment of cervical spinal cord tumor in patients combined with spinal stenosis.

Limaprost or Pregabalin: Preoperative and Postoperative Medication for Pain due to Lumbar Spinal Stenosis.

PURPOSE: We aimed to evaluate the incidence of (and risk factors for) postoperative pregabalin and/or limaprost to treat persistent numbness and/or pain of the lower extremities after lumbar spinal stenosis (LSS) surgery. METHODS: Medical records of 329 patients (168 men, 161 women; average age 70 years) were retrospectively reviewed for data on the duration of LSS diagnosis; LSS disease; preoperative medication (limaprost, pregabalin, or combined limaprost/pregabalin; duration); symptoms; preoperative/postoperative intermittent claudication (IC); operation type; and postoperative medication and period. RESULTS: Limaprost, pregabalin, and combined limaprost/pregabalin were prescribed preoperatively for 43%, 7%, and 5% of patients, respectively. At an average of 21 months postoperatively, limaprost, pregabalin, and combined therapy were prescribed in 11%, 8%, 4% of patients, respectively. Medication requirement was significantly lower postoperatively than preoperatively (P < 0.0001). Significant risk factors for required postoperative medication were required preoperative medication (odds ratio [OR] 3.088, 95% confidence interval [CI] 1.679 to 5.681]; postoperative period (OR 1.063, 95% CI 1.031 to 1.096); and postoperative IC (OR 3.868, 95% CI 1.481 to 10.103). A negative impact from postoperative medication was seen in patients who had undergone decompression surgery (OR 0.589, 95% CI 0.377 to 0.918). CONCLUSIONS: Overall, 23% of LSS patients required medication for pain and/or numbness at 21 months postoperatively. Significant factors portending required postoperative medication were preoperative medication, longer postoperative period, and postoperative IC. A negative influence from postoperative medication was seen in patients who had undergone decompression surgery without fusion.