Potential of whole-body dual-energy X-ray absorptiometry to predict muscle size of psoas major, gluteus maximus and back muscles

BACKGROUND

Measurement of trunk muscle cross-sectional area (CSA) using axial magnetic resonance imaging (MRI) is considered clinically meaningful for understanding several spinal pathologies, such as low back pain and spinal sagittal imbalance. However, it remains unclear whether trunk muscle mass (TMM) measured using dual-energy X-ray absorptiometry (DXA) can predict the trunk muscle CSA. The aim of this study is to determine if DXA-derived TMM is associated and predicts with CSA of paraspinal muscles and gluteus maximus measured using MRI in healthy volunteers.

METHODS

A total of 48 healthy volunteers underwent whole-body DXA and MRI of the spinopelvic region. The CSA of the psoas major, back muscles, and gluteus maximus were measured on axial MRI. Correlations and linear regressions between the TMM measured using DXA and the CSA of each musculature were investigated.

RESULTS

There was a weak correlation between TMM and CSA of the psoas major in men (r = 0.39, P = 0.0678), and the linear regression was y = 301.74x - 401.24 (R2 = 0.2976, P = 0.0070). A moderate correlation was found in women (r = 0.58, P = 0.0021), and the linear regression was y = 230.21x - 695.29 (R2 = 0.4445, P = 0.0003). Moderate correlations were observed between TMM and CSA of the back muscles in both men (r = 0.63, P = 0.0012) and women (r = 0.63, P = 0.0007), the linear regression was y = 468.52x + 3688.5 (R2 = 0.5505, P < 0.0001) in men and y = 477.39x + 2364.1 (R2 = 0.564, P < 0.0001) in women. There was a strong correlation between TMM and CSA of the gluteus maximus in men (r = 0.72, P < 0.0001), and the linear regression was y = 252.69x - 880.5 (R2 = 0.6906, P < 0.0001). A moderate correlation was found in women (r = 0.69, P < 0.0001), and the linear regression was y = 230.74x - 231.32 (R2 = 0.6542, P < 0.0001).

CONCLUSIONS

The DXA-derived TMM was able to predict the CSA of the psoas major, back muscles, and gluteus maximus, and significantly correlated with the CSA of the back muscles and gluteus maximus. It might be a safer and cheaper alternative for evaluating the size of the back muscles and gluteus maximus.

Posterior lumbar fusion surgery doesn't change sexual activities in patients with lumbar degenerative disease: an observational study

BACKGROUND

There are few studies about sexual function in the patient with posterior lumbar spinal fusion for degenerative lumbar disease. The aim of this study is to investigate sexual activities in patients with lumbar degenerative disease before and after lumbar fusion surgery.

METHODS

We recruited 35 patients who underwent lumbar spinal fusion at the age of 55 years or younger. They were 17 men and 18 women with a mean age of 47.4 years. After informed consent, the patients were asked to complete anonymous questionnaire concerning sexual desire, activity, and satisfaction before and after surgery.

RESULTS

In the presick period, 69% of the patients had sexual desire, and 79% achieved satisfaction during sexual activity. Lumbar degenerative disease decreased sexual desire and frequency of sexual activity in 40%, and 74% respectively. Before surgery, satisfaction in sexual activities decreased in 53%, and 55% of the patients felt discomfort during sexual activity. Adjustment in sexual position was required in 44% of man and 54% of woman. After surgery, Sexual desire, frequency of sexual activity and satisfaction did not regain after surgery in 94%, 93% and 92%, respectively. Those who did not feel discomfort after surgery was significantly lower VAS in both low back pain and leg pain than the patients felt discomfort (low back pain; p = 0.024, leg pain; p = 0.046).

CONCLUSION

This study demonstrated that lumbar degenerative diseases decreased sexual desire, frequency of sexual activity and satisfaction, and little of the patients regained their sexual activities after posterior lumbar fusion surgery in the middle-aged patients.

Characteristics of older patients with postmenopausal osteoporosis who developed loss of muscle mass during the COVID-19 pandemic - a case-control study

BACKGROUND

Under the restriction of social activities during the coronavirus disease 2019 (COVID-19) pandemic, there was concern about the loss of muscle mass due to a decrease in physical activity for the elderly. The purpose of this study was to investigate the characteristics of older patients with postmenopausal osteoporosis who developed loss of muscle mass during the COVID-19 pandemic in Japan.

METHODS

A total of 54 patients with postmenopausal osteoporosis were evaluated in this study. Whole-body dual-energy X-ray absorptiometry was performed pre- and post-COVID-19 pandemic to measure trunk and lower limb muscle mass. At the time of the post-COVID-19 pandemic, we conducted a survey to compare lifestyle before pandemic (the frequency of going out, the frequency of meeting acquaintances or families living apart, regular exercise habits, walking time, family structure), and comorbidities between the muscle mass loss (ML) group and the muscle mass maintenance (MM) group. The ML group consisted of patients with at least a 5% decrease in lower limb muscle mass or trunk muscle mass.

RESULTS

A significant difference was found only for the family structure (P = 0.0279); in the ML group, those living alone were the largest group, while in the MM group they were the smallest group.

CONCLUSIONS

The ML group was significantly more likely to live alone than the MM group. The current study showed that loss of muscle mass was more common in patients living alone.

Clinical outcomes of short-segment lumbar fusion in patients older than 85 years with a minimum 2-year follow-up

OBJECTIVE

Although the number of elderly patients requiring lumbar fusion for lumbar degenerative disorders has increased over time, the postoperative outcomes of lumbar fusion in very elderly patients (> 85 years) remains unknown. This study aimed to evaluate the comprehensive outcomes of lumbar fusion in elderly patients older than 85 years with mid-term follow-up.

METHODS

The authors retrospectively researched patients older than 85 years who underwent single- or double-level posterior lumbar interbody fusion or transforaminal lumbar interbody fusion from 2012 to 2019. Twenty-nine patients who had at least 2 years of follow-up were included in this study. The average age was 86.4 years, and the average follow-up period was 42.2 months. Each patient was matched with 60- to 75-year-old controls. The Oswestry Disability Index (ODI) score; Roland-Morris Disability Questionnaire (RMDQ) score; Japanese Orthopaedic Association (JOA) score; JOA recovery rate; and low-back pain (LBP), leg pain, and leg numbness visual analog scale (VAS) scores were obtained. The spinopelvic parameters were measured using lateral standing radiographs of the whole spine.

RESULTS

Although there were no significant differences in the ODI, RMDQ, JOA recovery rate, and leg pain and leg numbness VAS scores at 2 years postoperatively between the very elderly and control groups, the VAS LBP score was significantly lower in the very elderly group than in the control group. Preoperative and postoperative sagittal vertical axes were significantly higher and sacral slopes were significantly lower in the very elderly group than in the control group. The incidences of postoperative delirium and new lumbar vertebral fracture were significantly higher in the very elderly group (17.2%) than in the control group (4.6%).

CONCLUSIONS

This study showed that lumbar fusion could be performed in patients older than 85 years with satisfactory postoperative outcomes at the 2-year follow-up. In contrast, progressive spinopelvic sagittal imbalance, the incidence of lumbar vertebral fracture up to the final follow-up, and postoperative delirium were greater in the very elderly group than in the control group.

Aggravation of Ossified Ligamentum Flavum Lesion Is Associated With the Degree of Obesity

STUDY DESIGN

Retrospective cross-sectional study.

OBJECTIVES

There is insufficient data on the clinical features of ossification of the ligamentum flavum (OLF) of the thoracic spine and the risk of progression of ossified lesions. The link between obesity and ossification of the posterior longitudinal ligament (OPLL), which frequently coexists with OLF, has been demonstrated. However, the link between obesity and OLF has not been recognized. We aimed to determine the prevalence of obesity in thoracic OLF and whether the severity of OLF is associated with the degree of obesity.

METHODS

A total of 204 symptomatic Japanese subjects with thoracic OLF and 136 subjects without spinal ligament ossification as controls were included. OLF subjects were divided into 3 groups: 1) localized OLF (OLF <2-intervertebral regions); 2) multilevel OLF (OLF ≥3-intervertebral regions); and 3) OLF + OPLL. The severity of OLF was quantified using the OLF index using computed tomography imaging of the entire spine.

RESULTS

The proportion of severely obese subjects (BMI ≥ 30 kg/m2) was significantly higher both in the multilevel OLF group (25.5%) and the OLF + OPLL group (44.3%) than in the localized OLF group (3.6%) and the control group (1.4%) (P < 0.01). BMI, age, and coexistence of cervical OPLL and lumbar OLF were associated with thoracic OLF index in the multiple regression analysis.

CONCLUSIONS

Our findings demonstrated that obesity is a distinct feature of multilevel OLF in the thoracic spine and that the severity of OLF is associated with the degree of obesity.

Characteristics of the Patients with Poor Clinical Outcomes After Symptomatic Postoperative Lumbar Epidural Hematoma

OBJECTIVE

Symptomatic postoperative lumbar epidural hematoma (PLEH) may lead to poor outcomes even after evacuation. This study aimed to verify the short-term clinical outcomes after the evacuation of PLEH and to clarify the characteristics of the patients with poor postoperative outcomes.

METHODS

Twenty-five patients (average age; 70.4 years) underwent PLEH evacuation after lumbar spine surgery. The mean follow-up period was 12.0 (range 3-37) months. Pre and postoperative Japanese Orthopedic Association scores and visual analog scale (VAS) of low back pain (LBP), leg pain, and leg numbness were retrospectively collected. The dural sac cross-sectional area at the most compressed level was measured on magnetic resonance imaging. The patients were classified into 2 groups: poor outcome group (P group) had less than 50% of Japanese Orthopedic Associationrecovery rate and good group (G group) with 50% or more recovery rate.

RESULTS

The rate of delayed evacuation (over 24 hours of onset) was significantly higher in P group than in G group (P = 0.027). There was no significant difference in dural sac cross-sectional areabetween the 2 groups (P = 0.438). VAS of LBP, leg pain, and leg numbness in G group significantly improved postoperatively. Although VAS of LBP and leg pain in P group significantly improved postoperatively, there was no significant difference between the pre and postoperative VAS of leg numbness.

CONCLUSIONS

Delayed evacuation of PLEH can lead to poor postoperative outcomes after lumbar spine surgery. Moreover, patients with poor outcomes remained with postoperative leg numbness. Early evacuation of symptomatic PLEH is key to avoid poor outcomes and persistent leg numbness.

Perioperative Complications of Open Spine Surgery in Older Adults over 90 Years of Age

Introduction

Despite perioperative risks in nonagenarian patients who undergo open spine surgery for degeneration disorder or spinal trauma being of great interest, the prevalence of complications in this group remains unclear. This study aims to examine the perioperative complications of open spine surgery in the elderly over 90 years of age.

Methods

Preoperative and intraoperative characteristics including the American Society of Anesthesiologists Physical Status (ASA-PS) class, type of surgery, and complications within 30 postoperative days were retrospectively collected from the medical records of nonagenarians who underwent open spine surgery between April 2004 and July 2019 at our spine centers.

Results

A total of 48 patients met the inclusion criteria of this study. All belong to ASA-PS class 2 (69%) or 3. Preoperative American Spinal Injury Association Impairment Scale grades in trauma group were grade A in 4 cases, B in 1 case, C in 5 cases, D in 11 cases, and E in 1 case. Major complications (deep surgical site infection, cardiac event, respiratory disorder, gastrointestinal hemorrhage, and renal failure) occurred in 13 cases, and the rate of overall perioperative complications was 45.8%. One patient who underwent cervical stabilization for cervical fracture dislocation died at postoperative 13 days due to respiratory disorder. The rates of major complications and overall perioperative complications were 3.6% and 14.3% in the degenerative group and 45.5% and 81.8% in the trauma group, respectively. Especially in the trauma group, respiratory disorder occurred in 7 cases, delirium in 11 cases, and urinary tract infection in 5 cases.

Conclusions

Although the perioperative complication rate reached 81.8% in spinal trauma cases, the complication rate in degenerative disorders was relatively low as 14.3%. Open spine surgery for degenerative disorders can be relatively safe even in nonagenarians, whereas the risks of perioperative complications, including respiratory disorder and delirium, were high in spinal trauma cases.

Pre-existing adjacent level foraminal stenosis does not affect the outcome of a single level lumbar interbody fusion

BACKGROUND

The aim of this study was to investigate whether or not pre-existing asymptomatic neuroforaminal stenosis adjacent to the fusion level develops adjacent segment disease (ASD) after single-level lumbar interbody fusion.

SUMMARY AND BACKGROUND DATA

Risk factors of ASD after spinal fusion have been well investigated, but there have been few studies focused on the relationship between ASD and pre-existing asymptomatic neuroforaminal stenosis.

METHODS

A total of 302 patients who had undergone a single-level lumbar interbody fusion were reviewed at a minimum of 2 year follow-up. They were 109 men and 193 women with a mean age of 68.8 years. Follow-up periods was averaged 53.5 months. ASD was defined as neurological deterioration related to adjacent segment pathologies which required an additional surgery. Based on the pathologies, patients were divided into three categories: ASD due to foraminal stenosis (ASD-FS), ASD due to central stenosis (ASD-CS), and ASD due to herniated disc (ASD-HD). Measured variables were age, gender, diagnosis, BMI, decompression procedures at adjacent segments, preoperative anterior/posterior slip, asymptomatic neuroforaminal stenosis, facet tropism, and postoperative spinopelvic parameters.

RESULTS

Thirty-eight patients (12.6%) developed ASD. There were 15 patients with ASD-FS, 18 patients with ASD-CS, and five patients with ASD-HD. Lumbar lordosis (LL) and sacral slope (SS) were significantly smaller and pelvic tilt (PT) was significantly larger in ASD-FS. Asymptomatic neuroforaminal stenosis was detected preoperatively in 33.3% of the ASD-FS group, and 18.6% of non-ASD group; the incidence was not significantly different.

CONCLUSIONS

Adjacent-level neuroforaminal stenosis was not a significant risk of ASD after single-level lumbar interbody fusion, and might not need to be fused if asymptomatic.

Trends of Spine Surgeries during the First COVID-19 Semi-Lockdown: Survey in a Non-Epidemic Region in Japan

Introduction

Methods

Results

Conclusions

Retinoic Acid Deficiency Underlies the Etiology of Midfacial Defects

Embryonic craniofacial development depends on the coordinated outgrowth and fusion of multiple facial primordia, which are populated with cranial neural crest cells and covered by the facial ectoderm. Any disturbance in these developmental events, their progenitor tissues, or signaling pathways can result in craniofacial deformities such as orofacial clefts, which are among the most common birth defects in humans. In the present study, we show that Rdh10 loss of function leads to a substantial reduction in retinoic acid (RA) signaling in the developing frontonasal process during early embryogenesis, which results in a variety of craniofacial anomalies, including midfacial cleft and ectopic chondrogenic nodules. Elevated apoptosis and perturbed cell proliferation in postmigratory cranial neural crest cells and a substantial reduction in Alx1 and Alx3 transcription in the developing frontonasal process were associated with midfacial cleft in Rdh10-deficient mice. More important, expanded Shh signaling in the ventral forebrain, as well as partial abrogation of midfacial defects in Rdh10 mutants via inhibition of Hh signaling, indicates that misregulation of Shh signaling underlies the pathogenesis of reduced RA signaling-associated midfacial defects. Taken together, these data illustrate the precise spatiotemporal function of Rdh10 and RA signaling during early embryogenesis and their importance in orchestrating molecular and cellular events essential for normal midfacial development.

Clinical Outcomes and Postoperative Radiographic Assessment of Osteoplastic Hemilaminectomy in the Treatment of Lumbar Foraminal Nerve Root Compression

Introduction

Osteoplastic hemilaminectomy for the treatment of lumbar foraminal nerve root compression is a safe technique as the exiting nerve root can be directly observed during neuroforaminal decompression without spinal fusion. Moreover, this procedure allows anatomical reconstruction of the posterior elements. However, there might be a potential risk for the progression of lumbar segmental instability after performing this procedure. This study aimed to review the radiographic and clinical outcomes of osteoplastic hemilaminectomy for the treatment of lumbar foraminal nerve root compression.

Methods

We retrospectively reviewed 51 patients who underwent osteoplastic hemilaminectomy with a minimum follow-up of 2 years. The clinical outcomes were evaluated using the visual analog scale (VAS) for low back pain, leg pain, and numbness and the Japanese Orthopaedic Association (JOA) score. Lumbar segmental instability was evaluated as a radiographic assessment using functional radiography. The mean follow-up period was 65 months.

Results

The preoperative VASs for low back pain, leg pain, and numbness were 46±31, 72±26, and 43±34, respectively, which were improved to 24±23, 19±23, and 19±23, respectively. The JOA score was also improved from 14±5 to 22±4. Three patients (5.9%) were reoperated due to recurrent disc herniation within 2 years following surgery. In addition, three patients (5.9%) developed postoperative lumbar segmental instability but did not require additional surgery.

Conclusions

The current study revealed that 94.1% of the patients who underwent osteoplastic hemilaminectomy achieved a significant improvement in the clinical outcomes and did not require additional surgery within 2 years following the procedure. Over a 5-year follow-up on average, 5.9% of the subjects developed postoperative lumbar segmental instability; however, they have maintained acceptable clinical conditions.

Thrombocytopenia Associated with Unrecognized Non-Alcoholic Fatty Liver Disease Is an Independent Predictor of Perioperative Significant Blood Loss in Cervical Laminoplasty

OBJECTIVE

To identify risk factors for significant blood loss (SBL) in cervical laminoplasty, especially regarding thrombocytopenia and coagulopathy resulting from non-alcoholic fatty liver disease (NAFLD).

METHODS

We retrospectively investigated differences in patient background data, laboratory data at the time of admission, and surgery-related data of 317 patients who underwent cervical laminoplasty and were divided into SBL (estimated blood loss [EBL] + drainage [D] ≥500 g) and non-SBL (EBL + D < 500 g) groups. To evaluate liver status, we used the fibrous 4 index and considered fibrous 4 index ≥1.85 as a representative phenotype for NAFLD with liver fibrosis. In addition, the risk factor for perioperative SBL was investigated using multiple logistic regression analysis, and the cutoff value was calculated.

RESULTS

Incidence of perioperative SBL in cervical laminoplasty was 7.3% (23/317). Compared with the non-SBL group, the SBL group demonstrated significantly lower platelet count (PLT), lower aspartate aminotransferase, longer operation time, and greater number of opened laminae. According to multivariate analysis, lower PLT and a greater number of opened laminae were identified as significant risk factors for perioperative SBL. The cutoff value of PLT for predicting SBL was determined to be 16.7 × 10⁴/μL using a receiver operating characteristic curve. The liver fibrosis group revealed significantly lower PLT and greater EBL + D than the non-liver fibrosis group.

CONCLUSIONS

Thrombocytopenia is an independent predictor of perioperative SBL in cervical laminoplasty. Thus, patients with mild thrombocytopenia that may be associated with NAFLD must be carefully monitored to avoid perioperative SBL.

Close association between non-alcoholic fatty liver disease and ossification of the posterior longitudinal ligament of the spine

Ossification of the posterior longitudinal ligament (OPLL) of the spine is a disease of unknown etiology occurring frequently in individuals with metabolic disturbances. Obesity has been suggested as a potential risk factor for the severity of OPLL. We aimed to investigate whether non-alcoholic fatty liver disease (NAFLD) is associated with OPLL severity. We assessed the severity of NAFLD by a liver-to-spleen (L/S) ratio on computed tomography (CT) scans of 85 symptomatic OPLL patients at a single institution in Japan. We also assessed the severity of OPLL by CT reconstruction sagittal and axial images. The prevalence of NAFLD in middle-aged patients (age < 70 years, n = 50) was 80.3%, which was 2.5-8 times higher than that in the general Japanese population (9-30%). The ossification index of the spinal ligaments increased in proportion to the severity of fatty liver. The L/S ratio was revealed as a significant risk factor associated with the total ossification index (standardized β: -0.40, 95% confidence interval - 54.34 to - 4.22). This study suggests the potential contribution of NAFLD to the progression of OPLL. The close association between NAFLD and OPLL demonstrated in this study warrants further study to elucidate the causal nature of this relationship.

Exceptional Conditions for Favorable Neurological Recovery After Laminoplasty in Cases with Cervical Myelopathy Caused by K-line (-) Ossification of Posterior Longitudinal Ligament

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

To clarify the exceptional conditions for a favorable neurological recovery after laminoplasty (LMP) for cervical myelopathy caused by K-line (-) ossification of the posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

The K-line-based classification of cervical OPLL was developed to predict insufficient neurological recovery after LMP. For patients with K-line (-) OPLL, LMP generally yields the least improvement because of inadequate decompression of the spinal cord; however, there are some exceptional cases wherein LMP promotes favorable neurological recoveries.

METHODS

We retrospectively reviewed the medical records of 106 consecutive patients who underwent LMP for cervical OPLL to determine the demographic data, radiographic findings, and neurological recoveries of the patients as assessed preoperatively and 2 years postoperatively by their Japanese Orthopedic Association (JOA) scores. The factors associated with favorable outcomes after LMP in patients with K-line (-) were then investigated.

RESULTS

Of 106 total patients, 31 were classified as K-line (-), of whom 21 achieved the least neurological recovery after LMP (JOA recovery rate <50%), while the remaining 10 patients achieved favorable outcomes (JOA recovery rate ≥50%). Among the K-line (-) group patients, those with ext-K-line (+), which changed to K-line (+) in the neck-extended position, and the patients with up-K-line (-), in whom the lesion responsible for myelopathy in the upper cervical spine (C3 or above), showed favorable neurological recoveries after LMP.

CONCLUSION

Our data shows that, even for patients with K-line (-) OPLL, a favorable neurological recovery can be expected after LMP in cases in which the OPLL is in the upper cervical spine or the K-line changes to (+) in the neck-extended position. This means that K-line-based predictions of surgical outcomes after LMP should be indicated for patients with OPLL in the middle and lower cervical spine with limited extension mobility.Level of Evidence: 4.

Bone Marrow Aspirate Concentrate Combined with in Situ Forming Bioresorbable Gel Enhances Intervertebral Disc Regeneration in Rabbits

BACKGROUND

The current surgical procedure of choice for intervertebral disc (IVD) herniation is discectomy, which induces postoperative IVD degeneration. Thus, cell-based therapies, as a 1-step simple procedure, are desired because of the poor capacity of IVDs for self-repair. The aim of this study was to investigate the repair efficacy of ultra-purified alginate (UPAL) gels containing bone marrow aspirate concentrate (BMAC) for the treatment of discectomy-associated IVD degeneration in rabbits.

METHODS

The mechanical properties of 3 types of gels-UPAL, UPAL containing bone marrow-derived mesenchymal stem cells (BMSCs), and UPAL containing BMAC-were evaluated. Forty rabbits were assigned to 5 groups: intact control, discectomy (to make the cavity), UPAL (implantation of the UPAL gel after discectomy), BMSCs-UPAL (implantation of a combination of autogenic BMSCs and UPAL gel after discectomy), and BMAC-UPAL (implantation of a combination of BMAC and UPAL gel after discectomy). The gels were implanted at 4 weeks after induction of IVD degeneration. At 4 and 12 weeks, magnetic resonance imaging (MRI) as well as histological and immunohistochemical analyses were performed to analyze IVD degeneration qualitatively and the viability of the implanted cells.

RESULTS

There was no significant difference among the 3 types of gels in terms of the results of unconfined compression tests. The implanted cells survived for 12 weeks. The histological grades of the BMSCs-UPAL (mean and standard deviation, 2.50 ± 0.53; p < 0.001) and BMAC-UPAL (2.75 ± 0.64, p = 0.001) showed them to be more effective in preventing degeneration than UPAL gel alone (3.63 ± 0.52). The effectiveness of BMAC-UPAL was not significantly different from that of BMSCs-UPAL, except with respect to type-II collagen synthesis.

CONCLUSIONS

BMAC-UPAL significantly enhanced the repair of IVD defects created by discectomy. This approach could be an effective therapeutic strategy owing to its simplicity and cost-effectiveness compared with cell therapy using culture-expanded BMSCs.

CLINICAL RELEVANCE

Local administration of the BMAC combined with UPAL gel could be an effective therapeutic strategy to enhance IVD repair after discectomy.

Ultra-purified alginate gel implantation decreases inflammatory cytokine levels, prevents intervertebral disc degeneration, and reduces acute pain after discectomy

Lumbar intervertebral disc (IVD) herniation causes severe low back pain (LBP), which results in substantial financial and emotional strains. Despite the effectiveness of discectomy, there is no existing treatment for post-operative LBP induced by progressive IVD degeneration. Two key factors of LBP are intradiscal inflammation, indicated by tumour necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), and sensory nerve ingrowth into the inner layer of the annulus fibrosus, triggered by nerve growth factor/high-affinity tyrosine kinase A (TrkA) signalling. In an animal models of discectomy, the bioresorbable ultra-purified alginate (UPAL) gel with an extremely low-toxicity has been effective in acellular tissue repair. We aimed to investigate whether UPAL gel can alleviate LBP using a rat nucleus pulposus (NP) punch model and a rabbit NP aspirate model. In both models, we assessed TNF-α and IL-6 production and TrkA expression within the IVD by immunohistochemistry. Further, histological analysis and behavioural nociception assay were conducted in the rat model. UPAL gel implantation suppressed TNF-α and IL-6 production, downregulated TrkA expression, inhibited IVD degeneration, and reduced nociceptive behaviour. Our results suggest the potential of UPAL gel implantation as an innovative treatment for IVD herniation by reducing LBP and preventing IVD degeneration after discectomy.

Bone marrow mesenchymal stem cells combined with ultra-purified alginate gel as a regenerative therapeutic strategy after discectomy for degenerated intervertebral discs

BACKGROUND

Because the regenerative ability of intervertebral discs (IVDs) is restricted, defects caused by discectomy may induce insufficient tissue repair leading to further IVD degeneration. An acellular bioresorbable biomaterial based on ultra-purified alginate (UPAL) gel was developed to fill the IVD cavity and prevent IVD degeneration. However, an acellular matrix-based strategy may have limitations, particularly in the elderly population, who exhibit low self-repair capability. Therefore, further translational studies involving product combinations, such as UPAL gel plus bone marrow-derived mesenchymal stem cells (BMSCs), are required to evaluate the regenerative effects of BMSCs embedded in UPAL gel on degenerated IVDs.

METHODS

Rabbit BMSCs and nucleus pulposus cells (NPCs) were co-cultured in a three-dimensional (3D) system in UPAL gel. In addition, rabbit or human BMSCs combined with UPAL gel were implanted into IVDs following partial discectomy in rabbits with degenerated IVDs.

FINDINGS

Gene expression of NPC markers, growth factors, and extracellular matrix was significantly increased in the NPC and BMSC 3D co-culture compared to that in each 3D mono-culture. In vivo, whereas UPAL gel alone suppressed IVD degeneration as compared to discectomy, the combination of BMSCs and UPAL gel exerted a more potent effect to induce IVD regeneration. Similar IVD regeneration was observed using human BMSCs.

INTERPRETATION

These findings demonstrate the therapeutic potential of BMSCs combined with UPAL gel as a regenerative strategy following discectomy for degenerated IVDs.

FUNDING

Ministry of Education, Culture, Sports, Science, and Technology of Japan, Japan Agency for Medical Research and Development, and the Mochida Pharmaceutical Co., Ltd.

Ten years change in post-fracture care for hip fracture patients

INTRODUCTION

This multicenter, retrospective study aimed to clarify the changes in postoperative care provided by orthopaedic surgeons after hip fractures and clarify the incidence of secondary fractures requiring surgery.

MATERIALS AND METHODS

Subjects were patients with hip fracture treated surgically in seven hospitals during the 10-year period from January 2008 to December 2017. Data on patient demographics, comorbidities, preoperative and postoperative osteoporosis treatments, and secondary fractures were collected from the medical records.

RESULTS

In total, 4764 new hip fractures in 982 men and 3782 women (mean age: 81.3 ± 10.0 years) were identified. Approximately 10% of patients had a history of osteoporosis drug treatment and 35% of patients received postoperative drug treatment. The proportion of patients receiving postoperative drug therapy increased by approximately 10% between 2009 and 2010, 10% between 2010 and 2011, and 10% between 2011 and 2013. Although the rate of secondary fractures during the entire period and within 3 years decreased from 2011, the rate of secondary fracture within 1 year remained at around 2% every year.

CONCLUSIONS

The approval of new osteoporosis drugs and the establishment of osteoporosis liaison services have had a positive effect on the use of postoperative drug therapy in the orthopedic field. Our finding that the rate of secondary fracture within 1 year of the initial fracture remained around 2% every year, despite improvements in postoperative drug therapy, suggests that both rehabilitation for preventing falls and early postoperative drug therapy are essential to prevent secondary fractures.

Effects of Intradiscal Injection of Local Anesthetics on Intervertebral Disc Degeneration in Rabbit Degenerated Intervertebral Disc

Analgesic discoblock is widely used for the diagnosis or treatment of discogenic low back pain by injecting local anesthetics. The purpose of this study was to investigate the deleterious effects of local anesthetics on degenerated rabbit intervertebral disks (IVDs) using an organotypic culture model and in vivo long-term follow-up model. To induce IVD degeneration, a rabbit annular puncture model was used. For the organotypic culture model, degenerated IVDs were harvested 1 month after the initial annular puncture and cultured for 3 or 7 days after intradiscal injection of local anesthetics (1% lidocaine and 0.5% bupivacaine). To perform in vivo analysis, local anesthetics were injected into degenerated IVDs, and IVDs were prepared for histological analysis after 6 or 12 months. In the organotypic model, terminal deoxynucleotidyl transferase dUTP nick end labeling-positive nucleus pulposus (NP) cells were significantly increased in the bupivacaine group compared with the other groups. In the in vivo study, the number of NP cells was significantly decreased in the saline and local anesthetics groups compared with the untreated control and puncture-only groups. However, there was no significant difference among the saline, lidocaine, and bupivacaine groups. In addition, histological analysis showed no significant difference of IVD degeneration among the puncture-only, saline, lidocaine, and bupivacaine groups. Although bupivacaine induced apoptotic NP cell death in the organotypic culture model, in vivo observations did not show any definitive proof to suggest that local anesthetics were capable of promoting degeneration in the degenerated IVD, except for pressurized injection-induced damage. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1963-1971, 2019.

An acellular bioresorbable ultra-purified alginate gel promotes intervertebral disc repair: A preclinical proof-of-concept study

Background

The current surgical procedure of choice for lumbar intervertebral disc (IVD) herniation is discectomy. However, defects within IVD produced upon discectomy may impair tissue healing and predispose patients to subsequent IVD degeneration. This study aimed to investigate whether the use of an acellular bioresorbable ultra-purified alginate (UPAL) gel implantation system is safe and effective as a reparative therapeutic strategy after lumbar discectomy.

Methods

Human IVD cells were cultured in a three-dimensional system in UPAL gel. In addition, lumbar spines of sheep were used for mechanical analysis. Finally, the gel was implanted into IVD after discectomy in rabbits and sheep in vivo.

Findings

The UPAL gel was biocompatible with human IVD cells and promoted extracellular matrix production after discectomy, demonstrating sufficient biomechanical characteristics without material protrusion.

Interpretation

The present results indicate the safety and efficacy of UPAL gels in a large animal model and suggest that these gels represent a novel therapeutic strategy after discectomy in cases of lumbar IVD herniation.

Fund

Grant-in-Aid for the Ministry of Education, Culture, Sports, Science, and Technology of Japan, Japan Agency for Medical Research and Development, and the Mochida Pharmaceutical Co., Ltd.

Effects of a combined exercise plus diet program on cardiorespiratory fitness of breast cancer patients

Background

Decreases in cardiorespiratory fitness among breast cancer patients have often been reported in previous studies, affecting patients’ health and survival. Peak oxygen uptake (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\dot{V}\text{O}}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak) is the gold standard for assessing cardiorespiratory fitness and is inversely correlated with cardiovascular disease among women with breast cancer. Some previous studies have reported that aerobic exercise and proper diet positively influence \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\dot{V}\text{O}}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak. However, almost all studies have been conducted in the Western countries, and few studies are investigating on Asian women who have lower BMI compared with Western ones.

Purpose

Investigating the effects of a combined exercise and diet program among Japanese cancer patients undergoing therapy on \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\dot{V}\text{O}}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak.

Methods

Thirty-two Japanese women with breast cancer undergoing endocrine therapy (age; 50 ± 6 years, body weight; 59 ± 10 kg) were voluntarily assigned to either intervention group (n = 21) or control group (n = 11). The intervention group completed a 12-week combined exercise plus diet program, consisting of weekly aerobic exercise and maintaining a nutritionally well-balanced 1200 kcal/day diet. The control group was instructed to continue with their usual activities. Anthropometric indices and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\dot{V}\text{O}}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak were measured at baseline and after the 12-week program.

Results

All 21 women completed the 12-week program. The \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{\dot{V}\text{O}}}_{{{\text{2peak}}}}$$\end{document}V˙O2peak significantly increased from 26.7 to 30.4 mL/kg/min (1.57–1.62 L/min) in the intervention group, while it remained unchanged (26.9–26.9 mL/kg/min) in the control group. Mean reduction of body mass index was − 2.1 in the intervention group (P < .001) and + 0.1 in the control group.

Conclusions

Our combined exercise plus diet program may contribute to improvement in cardiorespiratory fitness and body weight compared with control group.

Abstract P6-11-04: Effects of a combined exercise plus diet intervention on cardiorespiratory fitness among Japanese women with breast cancer: A feasibility study

Background

Remarkable deterioration of physical fitness is a well-established adverse event associated with endocrine therapy among breast cancer patients. Especially, impairment in cardiorespiratory fitness has been often reported in previous studies, affecting patients' health and survival. Peak oxygen uptake (VO2peak) is the gold standard for assessing cardiorespiratory fitness and is inversely correlated with cardiovascular disease among women with breast cancer as well as ordinal people. A number of previous studies have reported that aerobic exercise improves the risk of cardiovascular disease. Moreover, a proper diet program positively influences VO2peak. However, almost all studies have been conducted in the Western community and there are few studies forcing on Asian women who have lower BMI compared with Western ones. Therefore, we investigated the feasibility of a combined exercise and diet program among Japanese cancer patients undergoing endocrine therapy and the effect on VO2peak.

Methods

Thirty-Two Japanese women with breast cancer undergoing endocrine therapy (age; 50±6 years, body weight; 126±22 lbs) were voluntarily assigned to either intervention group (n = 21) or control group (n = 11). The intervention group completed a 12-week combined exercise plus diet program, consisting of weekly aerobic training and maintaining a nutritionally well-balanced 1,200 kcal/d diet. The control group were instructed to continue with their usual activities. Anthropometric indices, VO2peak and QoL were measured at baseline and after the 12-week program. VO2peak was assessed using an Okura protocol (Okura. 1999).

Results

All of the 21 women completed the 12-week program. The VO2peak increased from 26.7 to 30.4 mL/kg/min (1.57 to 1.62 L/min) in the intervention group, while it remained unchanged (26.6 to 26.7 mL/kg/min) in the control group. Significant improvements were observed in VO2peak, and QoL in the intervention group (P &lt;. 001), while they remained essentially unchanged among the control group. Mean weight loss was 8.7% of the initial weight in the intervention group (P &lt;. 001) and 0.1% in the control group. No adverse events were reported in the intervention group.

Conclusions

Our combined exercise plus diet program may contribute to improvement in cardiorespiratory fitness, QoL, and body weight compared with control group. Importantly, cardiorespiratory fitness has been improved by as much as 15 % after three months. Further studies are needed to consider that what kind of aerobic exercise is best to improve cardiorespiratory fitness among Asian breast cancer patients.

Citation Format: Okumatsu K, Tsujimoto T, Seki A, Kotake R, Yamauchi T, Yamauchi H, Tanaka K. Effects of a combined exercise plus diet intervention on cardiorespiratory fitness among Japanese women with breast cancer: A feasibility study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-11-04.

Age-related spontaneous lumbar intervertebral disc degeneration in a mouse model

The pathogenesis of intervertebral disc degeneration is unclear, but it is a major cause of several spinal diseases. Animal models have historically provided an appropriate benchmark for understanding the human spine. However, there is little information about when intervertebral disc degeneration begins in the mouse or regarding the relationship between magnetic resonance imaging and histological findings. The aim for this study was to obtain information about age-related spontaneous intervertebral disc degeneration in the mouse lumbar spine using magnetic resonance imaging and a histological score regarding when the intervertebral disc degeneration started and how rapidly it progressed, as well as how our histological score detected the degeneration. The magnetic resonance imaging index yielded a moderate correlation with our Age-related model score. The Pfirrmann grade and magnetic resonance imaging index had moderate correlations with age. However, our Age-related model score had a high correlation with age. Intervertebral disc level was not a significant variable for the severity of disc degeneration. Both Pfirrmann grade and the Age-related model score were higher in the ≥14-month-old group than in the 6-month-old group. The present results indicated that mild but significant intervertebral disc degeneration occurred in 14-month-old mice, and the degree of degeneration progressed slowly, reaching a moderate to severe condition for 22-month-old mice. At least a 14-month follow-up is mandatory for evaluating spontaneous age-related mouse intervertebral disc degeneration. The histological classification score can precisely detect the gradual progression of age-related spontaneous intervertebral disc degeneration in the mouse lumbar spine, and is appropriate for evaluating it. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:224-232, 2018.