Intraoperative Blood Loss at Different Surgical-Procedure Stages during Posterior Spinal Fusion for Idiopathic Scoliosis.

Background and Objectives: Several predictive factors have been reportedly associated with intraoperative total blood loss (TBL) during posterior spinal fusion (PSF) for idiopathic scoliosis (IS). To reduce TBL, preoperative factors and interoperative factors are considered important. However, there are few reports that have evaluated bleeding patterns according to surgical stages. This study aimed to elucidate bleeding patterns at different surgical stages and determine the predictive factors for TBL during PSF surgery in patients with IS. Materials and Methods: Preoperative data, radiographic parameters, and intraoperative data of patients undergoing PSF for IS were retrospectively collected. We divided the patients into six stages: stage 1, exposure; stage 2, implant placement; stage 3, release; stage 4, correction; stage 5, bone grafting; and stage 6, closure; then we reviewed the blood loss and bleeding speed. Multiple-regression analysis was performed to generate a predictive formula for blood loss using preoperative and intraoperative factors, including blood loss at stage 1, as explanatory variables. Results: Forty-five patients (mean age: 17.6 years) were included. The mean operative time and TBL were 287.9 min and 756.5 mL, respectively. Blood loss was the highest at stage 3, followed by stage 4. Bleeding speed was the highest at stage 4, followed by stage 3. Bleeding speeds at stages 3 and 4 were significantly higher than those at stages 1 and 2. Preoperative Cobb angle, activated partial thromboplastin time (aPTT), number of fused vertebrae, and blood loss at stage 1 were significant contributing factors. Conclusions: Blood loss and bleeding speed during the release and correction stages were high. Specifically, bleeding speed significantly increased during and after the release procedure. The preoperative Cobb angle, aPTT, number of fixed vertebrae, and blood-loss volume during PSF were significantly associated with TBL. Our findings would be helpful for reducing TBL in patients undergoing PSF for IS.

Posterior Spinal Fusion Surgery for Neuromuscular Disease Patients with Severe Scoliosis Whose Cobb Angle Was over 100 Degrees.

Background and objectives: Patients with neuromuscular diseases usually have progressive neuromuscular scoliosis (NMS), requiring invasive surgery. Some patients present with severe scoliosis at the time of consultation and are difficult to treat. Posterior spinal fusion (PSF) surgery combined with anterior release and pre- or intraoperative traction would be effective for severe spinal deformities but would be invasive. This study aimed to evaluate the outcomes of PSF-only surgery for patients with severe NMS with a Cobb angle > 100°. Materials and Methods: Thirty NMS patients (13 boys and 17 girls; mean age 13.8 years) who underwent PSF-only surgery for scoliosis with a Cobb angle > 100° were included. We reviewed the lower instrumented vertebra (LIV), duration of surgery, blood loss, perioperative complications, preoperative clinical findings, and radiographic findings, including Cobb angle and pelvic obliquity (PO) in the sitting position pre- and postoperatively. The correction rate and correction loss of the Cobb angle and PO were also calculated. Results: The mean duration of surgery was 338 min, intraoperative blood loss was 1440 mL, preoperative %VC was 34.1%, FEV1.0 (%) was 91.5%, and EF was 66.1%. There were eight cases of perioperative complications. The Cobb angle and PO correction rates were 48.5% and 42.0%, respectively. We divided the patients into two groups: the L5 group, in which the LIV was L5, and the pelvis group, in which the LIV was the pelvis. The duration of surgery and PO correction rate in the pelvis group were significantly higher than those in the L5 group. Conclusions: Patients with severe NMS demonstrated severe preoperative restrictive ventilatory impairments. PSF surgery without anterior release or any intra-/preoperative traction showed satisfactory outcomes, including acceptable scoliosis correction and improved clinical findings, even in patients with extremely severe NMS. Instrumentation and fusion to the pelvis for severe scoliosis in patients with NMS showed good PO correction and low correction loss of Cobb angle and PO, but a longer duration of surgery.

Decreased muscle mass and strength affected spinal sagittal malalignment.

PURPOSE: Correction surgeries for spinal malalignment showed good clinical outcomes; however, there were concerns including increased invasiveness, complications, and impact on medico-economics. Ideally, an early intervention is needed. To better understand the patho-mechanism and natural course of spinal alignment, the effect of factors such as muscle mass and strength on spinal sagittal imbalance were determined in a multicenter cross-sectional study. METHODS: After excluding metal implant recipients, 1823 of 2551 patients (mean age: 69.2 ± 13.8 years; men 768, women 1055) were enrolled. Age, sex, past medical history (Charlson comorbidity index), body mass index (BMI), grip strength (GS), and trunk muscle mass (TM) were reviewed. Spinal sagittal imbalance was determined by the SRS-Schwab classification. Multiple comparison analysis among four groups (Normal, Mild, Moderate, Severe) and multinomial logistic regression analysis were performed. RESULTS: On multiple comparison analysis, with progressing spinal malalignment, age in both sexes tended to be higher; further, TM in women and GS in both sexes tended to be low. On multinomial logistic regression analysis, age and BMI were positively associated with spinal sagittal malalignment in Mild, Moderate, and Severe groups. TM in Moderate and Severe groups and GS in the Moderate group were negatively associated with spinal sagittal malalignment. CONCLUSION: Aging, obesity, low TM, and low GS are potential risk factors for spinal sagittal malalignment. Especially, low TM and low GS are potentially associated with more progressed spinal sagittal malalignment. Thus, early intervention for muscles, such as exercise therapy, is needed, while the spinal sagittal alignment is normal or mildly affected.

A High Body Mass Index and the Vacuum Phenomenon Upregulate Pain-Related Molecules in Human Degenerated Intervertebral Discs.

Animal studies suggest that pain-related-molecule upregulation in degenerated intervertebral discs (IVDs) potentially leads to low back pain (LBP). We hypothesized that IVD mechanical stress and axial loading contribute to discogenic LBP's pathomechanism. This study aimed to elucidate the relationships among the clinical findings, radiographical findings, and pain-related-molecule expression in human degenerated IVDs. We harvested degenerated-IVD samples from 35 patients during spinal interbody fusion surgery. Pain-related molecules including tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-6, calcitonin gene-related peptide (CGRP), microsomal prostaglandin E synthase-1 (mPGES1), and nerve growth factor (NGF) were determined. We also recorded preoperative clinical findings including body mass index (BMI), Oswestry Disability Index (ODI), and radiographical findings including the vacuum phenomenon (VP) and spinal instability. Furthermore, we compared pain-related-molecule expression between the VP (-) and (+) groups. BMI was significantly correlated with the ODI, CGRP, and mPGES-1 levels. In the VP (+) group, mPGES-1 levels were significantly higher than in the VP (-) group. Additionally, CGRP and mPGES-1 were significantly correlated. Axial loading and mechanical stress correlated with CGRP and mPGES-1 expression and not with inflammatory cytokine or NGF expression. Therefore, axial loading and mechanical stress upregulate CGRP and mPGES-1 in human degenerated IVDs, potentially leading to chronic discogenic LBP.

TGF-ß regulates nerve growth factor expression in a mouse intervertebral disc injury model.

BACKGROUND: Intervertebral disc (IVD) degeneration is a major cause of low back pain (LBP). Following disc injury, nerve growth factor (NGF) concentrations rise in IVDs, and anti-NGF therapy has been shown to attenuate LBP in humans. Increased levels of tumor necrosis factor-α (TNF-α) and transforming growth factor-ß (TGF-ß) in degenerative IVDs and in in vitro studies suggest that these factors promote NGF production. However, whether these factors regulate NGF in vivo remains unclear. Thus, we studied NGF regulation in a mouse model of IVD injury. METHODS: After inducing IVD injury, we examined mRNA levels of Tnfa, Tgfb, and Ngf in IVDs from control and IVD-injured mice across 7 days. To do this, we used magnetic cell separation to isolate CD11b ( +) (macrophage-rich) and CD11b (-) (IVD cell-rich) cell fractions from injured IVDs. To study the effect of TNF-α on Ngf expression, we examined Ngf expression in injured IVDs from C57BL/6 J and Tnfa-knockout (KO) mice (C57BL/6 J background). To study the effect of TGF-ß on Ngf expression, C57/BL6J mice were given an intraperitoneal injection of either the TGF-ß inhibitor SB431542 or DMSO solution (vehicle) one and two days before harvesting IVDs. RESULTS: mRNA expression of Tnfa, Tgfb, and Ngf was significantly increased in injured IVDs. Tnfa was predominantly expressed in the CD11b ( +) fraction, and Tgfb in the CD11b (-) fraction. Ngf expression was comparable between CD11b ( +) and CD11b (-) fractions, and between wild-type and Tnfa-KO mice at post-injury day (PID) 1, 3, and 7. SB431542 suppressed TGF-ß-mediated Ngf expression and NGF production in vitro. Further, administration of SB431542 significantly reduced Ngf expression in IVDs such that levels were below those observed in vehicle-treated animals at PID3 and PID7. CONCLUSION: A TGF-ß inhibitor reduced Ngf expression in a mouse model of IVD injury, suggesting that TGF-ß may regulate NGF expression in vivo.

Prevalence and location of endplate fracture and subsidence after oblique lumbar interbody fusion for adult spinal deformity.

BACKGROUND: Recently, Oblique lumbar interbody fusion (OLIF) is commonly indicated to correct the sagittal and coronal alignment in adult spinal deformity (ASD). Endplate fracture during surgery is a major complication of OLIF, but the detailed location of fracture in vertebral endplate in ASD has not yet been determined. We sought to determine the incidence and location of endplate fracture and subsidence of the OLIF cage in ASD surgery, and its association with fusion status and alignment. METHODS: We analyzed 75 levels in 27 patients were analyzed using multiplanar CT to detect the endplate fracture immediately after surgery and subsidence at 1 year postoperatively. The prevalence was compared between anterior and posterior, approach and non-approach sides, and concave and convex side. Their association with fusion status, local and global alignment, and complication was also investigated. RESULTS: Endplate fracture was observed in 64 levels (85.3%) in all 27 patients, and the incidence was significantly higher in the posterior area compared with the anterior area (85.3 vs. 68.0%, p=0.02) of affected vertebra in the sagittal plane. In the coronal plane, there was no significant difference in incidence between left (approach) and right (non-approach) sides (77.3 and 81.3%, respectively), or concave and convex sides (69.4 and 79.6%) of wedged vertebra. By contrast, cage subsidence at 1 year postoperatively was noted in 14/75 levels (18.7%), but was not associated with endplate fracture. Fusion status, local and global alignment, and complications were not associated with endplate fracture or subsidence. CONCLUSION: Endplate fracture during OLIF procedure in ASD cases is barely avoidable, possibly induced by the corrective maneuver with ideal rod counter and cantilever force, but is less associated with subsequent cage subsidence, fusion status, and sustainment of corrected alignment in long fusion surgery performed even for elderly patients.

Identification of unapproved orthopedic regenerative medicine: Usefulness of the Act on Safety of Regenerative Medicine.

In Japan, the Act on Safety of Regenerative Medicine regulates unapproved regenerative medicine. Other nations market regenerative medicine products, bypassing regulatory approval. To identify unapproved orthopedic regenerative medicine, we have used data based on the Act. Platelet-rich plasma was often used. The common target was the knee. Prices averaged $2,490.

Muscle strength rather than appendicular skeletal muscle mass might affect spinal sagittal alignment, low back pain, and health-related quality of life.

Sarcopenia is defined as decreasing in muscle strength and mass, and dynapenia is defined as decreasing in muscle strength and maintained muscle mass. This study elucidated the prevalence and characteristics of sarcopenia and dynapenia and evaluate in elderly spinal disorders patients. 1039 spinal disorders patients aged ≥ 65 years were included. We measured age, grip strength, muscle mass, spinal sagittal alignment parameters, low back pain (LBP) scores and health-related quality of life (HR-QoL) scores. Based on the previous reports, patients were categorised into normal group: NG, pre-sarcopenia group: PG, dynapenia group: DG, and sarcopenia group: SG. Pre-sarcopenia, dynapenia, and sarcopenia were found in 101 (9.7%), 249 (19.2%), and 91 (8.8%) patients, respectively. The spinal sagittal alignment parameters, trunk muscle mass, LBP, and HR-QoL scores were significantly worse in DG and SG compared with those in PG and NG. Spinal alignment, trunk muscle mass, and clinical outcomes, including LBP and HR-QoL scores, were maintained in the PG and poor in the DG and SG. Thus, intervention for muscle strength may be a treatment option for changes of spinal sagittal alignment and low back pain.

Origin of M2 Mϕ and its macrophage polarization by TGF-ß in a mice intervertebral injury model.

INTRODUCTION: Studies have identified the presence of M1 and M2 macrophages (Mϕ) in injured intervertebral discs (IVDs). However, the origin and polarization-regulatory factor of M2 Mϕ are not fully understood. TGF-ß is a regulatory factor for M2 polarization in several tissues. Here, we investigated the source of M2 Mϕ and the role of TGF-ß on M2 polarization using a mice disc-puncture injury model. METHODS: To investigate the origin of M2 macrophages, 30 GFP chimeric mice were created by bone marrow transplantation. IVDs were obtained from both groups on pre-puncture (control) and post-puncture days 1, 3, 7, and 14 and CD86 (M1 marker)- and CD206 (M2 marker)-positive cells evaluated by flow cytometry (n = 5 at each time point). To investigate the role of TGF-ß on M2 polarization, TGF-ß inhibitor (SB431542) was also injected on post-puncture days (PPD) 5 and 6 and CD206 expression was evaluated on day 7 by flow cytometry (n = 5) and real time PCR (n = 10). RESULTS: The proportion of CD86+ Mϕ within the GFP+ population was significantly increased at PPD 1, 3, 7, and 14 compared to control. CD206-positive cells in GFP-populations were significantly increased on PPD 7 and 14. In addition, the percentage of CD206-positive cells was significantly higher in GFP-populations than in GFP+ populations. TGF-ß inhibitor reduced CD206-positive cells and Cd206 expression at 7 days after puncture. CONCLUSION: Our findings suggest that M2 Mϕ following IVD injury may originate from resident Mϕ. TGF-ß is a key factor for M2 polarization of macrophages following IVD injury.

Nerve decompression surgery suppresses TNF-ɑ expression and T cell infiltration in a rat sciatic nerve chronic constriction injury model.

Decompression surgery (DS) is a standard treatment for chronic nerve compression injuries; however, the mechanisms underlying its effects remain unclear. Here, we investigated the effects of DS on messenger RNA (mRNA) expression of tumor necrosis factor-α (TNF-α) and T cell recruitment in a rat sciatic nerve (SN) chronic constriction injury (CCI) model. Male Wistar rats were subjected to CCI to establish a model of SN injury (CCI group). DS, in which all ligatures were removed, was performed 3 days after CCI surgery (CCI + dec group). Mechanical sensitivity was assessed using the von Frey test 3, 7, and 14 days after the CCI surgery. Gene expression of Tnfa, Cd3, Cxcl10, and immunolocalization of TNF-α and the pan T cell marker, CD3, was evaluated using quantitative polymerase chain reaction (qPCR) and immunohistochemistry, respectively. In addition, the effects of TNF-α on Cxcl10 expression and CXCL10 protein production were evaluated using qPCR and enzyme-linked immunosorbent assay in SN cell culture. Rats that received DS had significantly higher withdrawal threshold levels than those in the CCI group. In addition, Tnfa, Cd3, and Cxcl10 mRNA expression increased following CCI. DS suppressed this elevated expression, with the CCI + dec group showing significantly reduced expression levels compared to the CCI group. Furthermore, TNF-α induced Cxcl10 expression and CXCL10 protein production in SN cell culture. Therefore, DS reduced TNF-α expression and T cell recruitment in the rat SN CCI model. These observations may partly explain the mechanism underlying the therapeutic effects of DS.

Reduced TGF-ß Expression and CD206-Positive Resident Macrophages in the Intervertebral Discs of Aged Mice.

Age is a key factor in intervertebral disc (IVD) degeneration; however, the changes that occur in IVDs with age are not fully understood. Tissue-resident macrophages are critical for tissue homeostasis and are regulated by transforming growth factor- (TGF-) ß. We examined changes in the proportion of resident macrophages in young versus aged mice and the role of TGF-ß in regulating resident macrophages in IVDs. IVDs were harvested from 4-month (young) and 18-month-old (aged) C57BL/6J mice. The proportion of macrophages in IVDs was determined using flow cytometry (n = 5 for each time point) and the expression of Cd11b, Cd206, and Tgfb genes, which encode CD11b, CD206, and TGF-ß protein, respectively, using real-time PCR. To study the role of TGF-ß in the polarization of resident macrophages, resident macrophages isolated from IVDs from young and aged mice were treated with recombinant TGF-ß with and without a TGF-ß inhibitor (SB431542). Additionally, SB431542 was intraperitoneally injected into young and aged mice, and Cd206 expression was examined using real-time PCR (n = 10 for each time point). The proportion of CD11b+ and CD11b+ CD206+ cells was significantly reduced in aged versus young mice, as was Cd11b, Cd206, and Tgfb expression. TGF-ß/IL10 stimulation significantly increased the expression of Cd206, an M2 macrophage marker, in disc macrophages from both young and aged mice. Meanwhile, administration of a TGF-ß inhibitor significantly reduced Cd206 expression compared to vehicle control in both groups. Conclusion. Resident macrophages decrease with age in IVDs, which may be associated with the concomitant decrease in TGF-ß. Our findings provide new insight into the mechanisms of age-related IVD pathology.

Posterior Spinal Correction and Fusion Surgery in Patients with Spinal Muscular Atrophy-Associated Scoliosis for Whom Treatment with Nusinersen Was Planned.

INTRODUCTION: Spinal muscular atrophy (SMA) is defined as a neuromuscular disorder induced by progressive weakness of the skeletal muscle and is usually accompanied by progressive spinal deformity including scoliosis. The newly developed Nusinersen, which is the first approved drug worldwide for SMA, requires accurate intrathecal injection, which is sometimes difficult in patients with severe spinal deformity. TECHNICAL NOTE: For an accurate intrathecal approach in patients who have spinal fusion surgery to treat neuromuscular scoliosis, we have combined an L3 laminectomy with spinal correction and fusion surgery. Here, we review four cases of SMA in patients who underwent the additional L3 laminectomy during surgery to treat spinal scoliosis. A successful intrathecal approach was made using fluoroscopic guidance in all four patients, who were then administered with Nusinersen. CONCLUSIONS: Our findings show that additional lumbar laminectomy during surgery for spinal scoliosis has effectively allowed for intrathecal injection of Nusinersen.

Incidence of Unintentional Intraoperative Hypothermia in Pediatric Scoliosis Surgery and Associated Preoperative Risk Factors.

INTRODUCTION: Intraoperative hypothermia is associated with perioperative complications such as blood loss and wound infection. Thus, perioperative heat retention methods to prevent perioperative hypothermia such as providing a warmed blanket and active patients' warming are important. Although major surgery and pediatric patient age are noted as risk factors, only a few studies focus on hypothermia as an intraoperative complication in pediatric scoliosis surgery. The aim of this study is to investigate the incidence of intraoperative hypothermia in pediatric scoliosis surgery and the associated preoperative risk factors. METHODS: We retrospectively reviewed the records of pediatric patients who underwent posterior spinal fusion at a single institution between 2015 and 2019. We recorded the background data, perioperative data, lowest recorded core temperature, and perioperative complications. Patients were divided into those whose temperature decreased below 36°C (Group H) and those who maintained a temperature of 36°C or greater (Group N) during surgery. We compared the two groups and performed multivariate analysis to identify preoperative risk factors for intraoperative hypothermia. RESULTS: A total of 103 patients underwent posterior spinal fusion; 56 for adolescent idiopathic scoliosis and 47 for neuromuscular scoliosis. Hypothermia was observed in 40 patients (38.8%). Group H had more non-adolescent idiopathic scoliosis (AIS) patients, lower mean body mass index, greater mean blood loss, greater number of fused vertebrae, larger preoperative Cobb angle, and lower initial core body temperature (immediately after induction of anesthesia). On multivariate analysis, a diagnosis of neuromuscular scoliosis, a lower body mass index, and a lower initial core body temperature were identified as independent risk factors for intraoperative hypothermia. CONCLUSIONS: The incidence of hypothermia in pediatric posterior scoliosis surgery is 38.8%. Diagnosis of non-AIS, lower body mass index, and lower core body temperature at the time of anesthesia induction are preoperative risk factors for intraoperative hypothermia.

Factors associated with pain-related disorders and gait disturbance scores from the Japanese orthopedic association back pain evaluation questionnaire and Oswestry Disability Index in patients with osteoporosis.

In the current study, multivariate analyses were performed to determine factors associated with low back pain (LBP) in patients with osteoporosis. Aging, high bone turnover, obesity, low trunk muscle mass, spinal global sagittal malalignment, and a high number of previous vertebral fractures were potential independent risk factors of pain-related disorders, gait disturbance, or ADL deficit due to LBP. PURPOSE: Patients with osteoporosis often experience low back pain (LBP) even in the absence of acute fractures. This study identifies factors that may affect questionnaires about LBP. METHODS: The data of 491 patients with osteoporosis were retrospectively reviewed. Data included patient age, sex, body mass index (BMI), bone mineral density of the lumbar spine, tartrate-resistant acid phosphatase 5b level (TRACP5b), trunk muscle mass, sagittal vertical axis (SVA), previous vertebral fractures, secondary osteoporosis, controlling nutritional status score, pain-related disorders and gait disturbance scores from the Japanese Orthopedic Association Back Pain Evaluation questionnaire (JOABPEQ), and Oswestry disability index (ODI) scores for activities of daily living (ADL) deficit. Patients with scores of 100 for each subsection of the JOABPEQ, or an ODI scores < 12 were considered to not have dysfunction (dysfunction (-) group). Multivariate analyses were used to determine variables associated with dysfunction. RESULTS: Pain-related disorders score of JOABPEQ was associated with aging, high BMI, and high SVA. Aging, high TRACP5b, high BMI, low TM, high SVA, and more previous vertebral fractures were associated with gait disturbance score of JOABPEQ. ODI scores were associated with high BMI, low TM, high SVA, and more previous vertebral fractures. CONCLUSIONS: Aging, high bone turnover, obesity, a low TM, spinal global sagittal malalignment, and a high number of previous VFs were potential independent risk factors of pain-related disorders or gait disturbance according to the JOABPEQ or ODI score in patients with osteoporosis.

Chylous retroperitoneum following 720 degree anteroposterior-combined corrective surgery for adult spinal deformity with split vertebral fracture subluxation: a case report.

STUDY DESIGN: Clinical case report. PURPOSE: To report the rare case with post-operative chylous retroperitoneum after corrective surgery for adult spinal deformity. METHODS: We present a case of a 73-year-old woman with Parkinson's disease. She sustained a severe split fracture subluxation of the L3 vertebra with AO Spine Thoracolumbar classification type CN2M2, resulting in severe kyphoscoliosis in global alignment. She underwent a two-stage 720-degree anteroposterior-combined corrective surgery with anterior vertebral column resection of L3 and posterior fusion from T4 to the pelvis. On post-operative day 1, milky fluid in the drainage tube was noted, which was diagnosed as post-operative chylous retroperitoneum. RESULTS: Oral intake was discontinued immediately and peripheral parenteral nutrition was started. A low-fat, high-protein diet was started on post-operative day 4, and drainage was removed on day 6. A low-fat diet was continued until 3 months post-operatively, with dietary counselling by a nutritionist. The chylous retroperitoneum resolved without recurrence at the final follow-up evaluation at 3 years. CONCLUSION: Surgeons should recognize this rare complication, which might be induced by direct damage to the lymphatic flow during an operative maneuver anterior to the lumbar vertebral body and indirect damage due to shearing force during correction of a subluxated vertebra, especially in cases with a severe deformity.

Prevalence and Characteristics of Spinal Sagittal Malalignment in Patients with Osteoporosis.

Spinal sagittal malalignment due to vertebral fractures (VFs) induces low back pain (LBP) in patients with osteoporosis. This study aimed to elucidate spinal sagittal malalignment prevalence based on VF number and patient characteristics in individuals with osteoporosis and spinal sagittal malalignment. Spinal sagittal alignment, and VF number were measured in 259 patients with osteoporosis. Spinal sagittal malalignment was defined according to the SRS-Schwab classification of adult spinal deformity. Spinal sagittal malalignment prevalence was evaluated based on VF number. In patients without VFs, bone mineral density, bone turnover markers, LBP scores and health-related quality of life (HRQoL) scores of normal and sagittal malalignment groups were compared. In 205 of the 259 (79.2%) patients, spinal sagittal malalignment was detected. Sagittal malalignment prevalence in patients with 0, 1, or ≥2 VFs was 72.1%, 86.0%, and 86.3%, respectively. All LBP scores and some subscale of HRQoL scores in patients without VFs were significantly worse for the sagittal malalignment group than the normal alignment group (p < 0.05). The majority of patients with osteoporosis had spinal sagittal malalignment, including ≥70% of patients without VFs. Patients with spinal sagittal malalignment reported worse LBP and HRQoL. These findings suggest that spinal sagittal malalignment is a risk factor for LBP and poor HRQoL in patients with osteoporosis.

Flexor Tenosynovitis Caused by Mycobacterium arupense: A Case Report and Review of the Literature.

CASE: A 64-year-old man presented with swelling of his right hand and forearm. This swelling had been recurring for 5 years. He liked sea fishing and frequently injured his fingers with fishhooks. He had difficulty bending his right little and ring fingers for 2 years and experienced finger numbness for several months. We diagnosed nontuberculous mycobacterial flexor tenosynovitis after Mycobacterium arupense was detected in a tissue sample. After surgery and 2 years of multidrug therapy, he has been recurrence-free for 3 years. CONCLUSION: Nontuberculous mycobacteriosis should be considered in chronic tenosynovitis cases.

Acceleration of bone union by in situ-formed hydrogel containing bone morphogenetic protein-2 in a mouse refractory fracture model.

BACKGROUND: An enzymatic crosslinking strategy using hydrogen peroxide and horseradish peroxidase is receiving increasing attention for application with in situ-formed hydrogels (IFHs). Several studies have reported the application of IFHs in cell delivery and tissue engineering. IFHs may also be ideal carrier materials for bone repair, although their potential as a carrier for bone morphogenetic protein (BMP)-2 has yet to be examined. Here, we examined the effect of an IFH made of hyaluronic acid (IFH-HA) containing BMP-2 in promoting osteogenesis in a mouse refractory fracture model. METHODS: Immediately following a fracture procedure, animals either received no treatment (control) or an injection of IFH-HA/PBS or IFH-HA containing 2 µg BMP-2 (IFH-HA/BMP-2) into the fracture site (n = 16, each treatment). RESULTS: Fracture sites injected with IFH-HA/BMP-2 showed significantly greater bone volume, bone mineral content, and bone union compared with sites receiving no treatment or treated with IFH-HA/PBS alone (each n = 10). Gene expression levels of osteogenic markers, Alpl, Bglap, and Osx, were significantly raised in the IFH-HA/BMP-2 group compared to the IFH-HA/PBS and control groups (each n = 6). CONCLUSION: IFH-HA/BMP-2 may contribute to the treatment of refractory fractures.

Loop-Mediated Isothermal Amplification Screening for COVID-19 in Asymptomatic Preoperative Orthopedic Patients in a General Hospital in Kanagawa, Japan.

The global coronavirus disease 2019 (COVID-19) pandemic has caused several million infections and hundreds of thousands of deaths. A large number of healthcare workers have died as a result of infection with this virus. Therefore, elective surgery was markedly reduced or stopped in our hospital's orthopedic department. The detection of asymptomatic COVID-19-positive patients became key to reducing the infection risk to physicians and staff to allow orthopedic surgery to be performed. A total of 21 patients were scheduled to undergo orthopedic surgery, including elective surgery, in Shonantobu General Hospital, Chigasaki City, Kanagawa, Japan. All 21 patients gave permission to undergo loop-mediated isothermal amplification (LAMP) screening the day before surgery. None of the 21 patients we tested was positive for COVID-19. All patients remained asymptomatic during the two to four weeks of postoperative follow-up. No physicians or medical staff developed COVID-19 symptoms. This was a very small study in a city with a relatively low incidence of COVID-19. We found that LAMP screening was accurate, in terms of its negative predictive value. Larger studies are needed.

Short-Term Impact of Staying Home on Bone Health in Patients With Osteoporosis During a State of Emergency Declaration Due to COVID-19 in Kanagawa, Japan.

Background On April 16, 2020, the Japanese government declared a state of emergency due to the spread of COVID-19 infection, leading prefectural governors to announce a stay-at-home order for 39 days until May 25, 2020. As physical inactivity is a risk factor for osteoporosis, we investigated the short-term impact of the stay-at-home order on bone health among patients with osteoporosis in our hospital in Kanagawa prefecture. Methods Thirty patients with osteoporosis with no delays in their regular medication who received care at our hospital's osteoporosis outpatient clinic within one month after the end of the state of emergency were included. Lumbar spine and femur proximal bone mineral density (BMD) were measured at the last follow-up date (May 25 to June 30, 2020; 0M) and six (6M) and 12 months (12M) before the last follow-up using dual-energy X-ray absorptiometry. Bone alkaline phosphatase (BAP), Tartrate-resistant Acid Phosphatase 5b (TRACP5b), calcium and phosphorus were assessed at the same time points. Results Serum BAP concentrations were significantly lower at 0M than 12M (p=0.040), but were comparable between 0M and 6M (p=0.527). Serum TRACP5b was significantly lower at 6M than 12M (p=0.009), but was similar between 0M and 6M (p=1.000). Serum calcium and phosphorus did not differ among the time points (p=0.516 and p=0.358, respectively). Similarly, lumbar spine and femoral neck BMD were comparable (p=0.679 and p=0.076, respectively). Conclusion Bone health in patients with osteoporosis was maintained during the short-term COVID-19 stay-at-home order among patients who experienced no delays in medication. However, larger and long-term studies are needed.