Risk Factors for Residual Back Pain After Balloon Kyphoplasty for Osteoporotic Vertebral Fracture.

Background: Balloon kyphoplasty (BKP) is a method for the management of osteoporotic vertebral body fracture (OVF). However, improvement in back pain (BP) is poor in some patients, also previous reports have not elucidated the exact incidence and risk factors for residual BP after BKP. We clarified the characteristics of residual BP after BKP in patients with OVF. Hypothesis: In this study, we hypothesize that some risk factors may exist for residual BP 2 years after the treatment of OVF with BKP. Patients and Methods: A multicenter cohort study was performed where patients who received BKP within 2 months of OVF injury were followed-up for 2 years. BP at 6 months after surgery and final observation was evaluated by Visual Analog Scale (VAS) score. Patients with a score of 40 mm or more were allocated to the residual BP group, and comparisons between the residual back pain group and the improved group were made for bone density, kyphosis, mobility of the fractured vertebral body, total spinal column alignment, and fracture type (fracture of the posterior element, pedicle fracture, presence or absence of posterior wall damage, etc.). Also, Short Form 36 (SF-36) for physical component summary (PCS) and mental component summary (MCS) at the final follow-up was evaluated in each radiological finding. Results: Of 116 cases, 79 (68%) were followed-up for 2 years. Two years after the BKP, 26 patients (33%) experienced residual BP. Neither age nor sex differed between the groups. In addition, there was no difference in bone mineral density, BKP intervention period (period from onset to BKP), and osteoporosis drug use. However, the preoperative height ratio of the vertebral body was significantly worse in the residual BP group (39.8% vs. 52.1%; p = 0.007). Two years after the operation, the vertebral body wedge angle was significantly greater in the residual BP group (15.7° vs. 11.9°; p = 0.042). In the multiple logistic regression model with a preoperative vertebral body height ratio of 50% or less [calculated by receiver operating characteristic (ROC) curve], the adjusted odds ratio for residual BP was 6.58 (95% confidence interval 1.64-26.30; p = 0.007); similarly, patients with vertebral body height ratio less than 50% had a lower score of SF-36 PCS 24.6 vs. 32.2 p = 0.08. Conclusion: The incidence of residual BP 2 years after BKP was 33% in the current study. The risk factor for residual BP after BKP was a preoperative vertebral body height ratio of 50% or less, which should be attentively assessed for the selection of a proper treatment scheme and to provide adequate stabilization. Level of Evidence: III.

Fracture healing on non-union fracture model promoted by non-thermal atmospheric-pressure plasma.

Non-thermal atmospheric-pressure plasma (NTAPP) is attracting widespread interest for use in medical applications. The tissue repair capacity of NTAPP has been reported in various fields; however, little is known about its effect on fracture healing. Non-union or delayed union after a fracture is a clinical challenge. In this study, we aimed to investigate how NTAPP irradiation promotes fracture healing in a non-union fracture model and its underlying mechanism, in vitro and in vivo. For the in vivo study, we created normal and non-union fracture models in LEW/SsNSlc rats to investigate the effects of NTAPP. To create a fracture, a transverse osteotomy was performed in the middle of the femoral shaft. To induce the non-union fracture model, the periosteum surrounding the fracture site was cauterized after a normal fracture model was created. The normal fracture model showed no significant difference in bone healing between the control and NTAPP-treated groups. The non-union fracture model demonstrated that the NTAPP-treated group showed consistent improvement in fracture healing. Histological and biomechanical assessments confirmed the fracture healing. The in vitro study using pre-osteoblastic MC3T3-E1 cells demonstrated that NTAPP irradiation under specific conditions did not reduce cell proliferation but did enhance osteoblastic differentiation. Overall, these results suggest that NTAPP is a novel approach to the treatment of bone fractures.

Short-Term Risk Factors for Distal Junctional Kyphosis after Spinal Reconstruction Surgery in Patients with Osteoporotic Vertebrae.

STUDY DESIGN: Level 3 retrospective cohort case-control study. PURPOSE: This study aimed to investigate the risk factors for distal junctional kyphosis (DJK) caused by osteoporotic vertebral fractures following spinal reconstruction surgery, with a focus on the sagittal stable vertebra. OVERVIEW OF LITERATURE: Despite the rarity of reports on DJK in this setting, DJK was reported to reduce when the lower instrumented vertebra (LIV) was extended to the sagittal stable vertebra in the posterior corrective fixation for Scheuermann's disease. METHODS: This study included 46 patients who underwent spinal reconstruction surgery for thoracolumbar osteoporotic vertebral fractures and kyphosis and were followed up for 1 year postoperatively. DJK was defined as an advanced kyphosis angle >10° between the LIV and one lower vertebra. The patients were divided into groups with and without DJK. The risk factors of the two groups, such as patient background, surgery-related factors, radiographic parameters, and clinical outcomes, were analyzed. RESULTS: The DJK and non-DJK groups included 14 and 32 patients, respectively, without significant differences in patient background. Those with instability in the distal adjacent LIV disc had a significantly higher risk of DJK occurrence (28.6% vs. 3.2%, p=0.027). DJK occurrence significantly increased in those with the sagittal stable vertebra not included in the fixation range (57.1% vs. 18.8%, p=0.020). Other preoperative radiographic parameters were not significantly different. Instability in the distal adjacent LIV disc (adjusted odds ratio, 14.50; p=0.029) and the exclusion of the sagittal stable vertebra from the fixation range (adjusted odds ratio, 5.29; p=0.020) were significant risk factors for DJK occurrence. CONCLUSIONS: Regarding spinal reconstruction surgery in patients with osteoporotic vertebral fractures, instability in the distal adjacent LIV disc and the exclusion of the sagittal stable vertebra from the fixation range were risk factors for DJK occurrence in the short term.

Degeneration of Cervical Multifidus Muscles Negatively Affects Physical Activity-related Quality of Life After Laminoplasty for Degenerative Cervical Myelopathy.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The study aimed to investigate the related factors affecting physical activity-related quality of life (QOL) after 2 years of cervical laminoplasty for degenerative cervical myelopathy (DCM), focusing on the degree of preoperative degeneration of the cervical multifidus muscles. SUMMARY OF BACKGROUND DATA: The association between paraspinal muscle degeneration and clinical outcomes after spinal surgery is being investigated. The effect of preoperative degeneration of the cervical multifidus muscles in patients undergoing cervical laminoplasty is ambiguous. METHODS: Patients who underwent laminoplasty for DCM and followed up for more than 2 years were reviewed. To evaluate physical QOL, the physical component summary (PCS) of the 36-Item Short-Form Health Survey (SF-36) was recorded at 2 years postoperatively. The degree of preoperative degeneration in the multifidus muscles at the C4 and C7 levels on axial T2-weighted magnetic resonance imaging (MRI) was categorized according to the Goutallier grading system. The correlation between 2-year postoperative PCS and each preoperative clinical outcome, radiographic parameter, and MRI finding, including Goutallier classification, was analyzed. Variables with a P value <0.10 in univariate analysis were included in multiple linear regression analysis. RESULTS: In total, 106 consecutive patients were included. The 2-year postoperative PCS demonstrated significant correlation with age (R=-0.358, P=0.002), preoperative JOA score (R=0.286, P=0.021), preoperative PCS (R=0.603, P<0.001), C2-C7 lordotic angle (R=-0.284, P=0.017), stenosis severity (R=-0.271, P=0.019), and Goutallier classification at the C7 level (R=-0.268, P=0.021). In multiple linear regression analysis, sex (ß=-0.334, P=0.002), age (ß=-0.299, P=0.013), preoperative PCS (ß=0.356, P=0.009), and Goutallier classification at the C7 level (ß=-0.280, P=0.018) were significantly related to 2-year postoperative PCS. CONCLUSIONS: Increased degeneration of the multifidus muscle at the C7 level negatively affected physical activity-related QOL postoperatively. These results may guide spine surgeons in predicting physical activity-related QOL in patients with DCM after laminoplasty. LEVEL OF EVIDENCE: Level III.

Residual Paresthesia After Surgery for Degenerative Cervical Myelopathy: Incidence and Impact on Clinical Outcomes and Satisfaction.

STUDY DESIGN: Multicenter, prospective cohort study. OBJECTIVE: The current study aimed to identify the incidence of residual paresthesias after surgery for degenerative cervical myelopathy (DCM), and to demonstrate the impact of these symptoms on clinical outcomes and patient satisfaction. SUMMARY OF BACKGROUND DATA: Surgery for DCM aims to improve and/or prevent further deterioration of physical function and quality-of-life (QOL) in the setting of DCM. However, patients are often not satisfied with their treatment for myelopathy when they have severe residual paresthesias, even when physical function and QOL are improved after surgery. MATERIALS AND METHODS: The authors included 187 patients who underwent laminoplasty for DCM. All patients were divided into two groups based on their visual analog scale score for paresthesia of the upper extremities at one year postoperatively (>40 vs. ≤40 mm). Preoperative factors, changes in clinical scores and radiographic factors, and satisfaction scales at one year postoperatively were compared between groups. The authors used mixed-effect linear and logistic regression modeling to adjust for confounders. RESULTS: Overall, 86 of 187 patients had severe residual paresthesia at one year postoperatively. Preoperative patient-oriented pain scale scores were significantly associated with postoperative residual paresthesia ( P =0.032). A mixed-effect model demonstrated that patients with severe postoperative residual paresthesia showed significantly smaller improvements in QOL ( P =0.046) and myelopathy ( P =0.037) than patients with no/mild residual paresthesia. Logistic regression analysis identified that residual paresthesia was significantly associated with lower treatment satisfaction, independent of improvements in myelopathy and QOL (adjusted odds ratio: 2.5, P =0.010). CONCLUSION: In total, 45% of patients with DCM demonstrated severe residual paresthesia at one year postoperatively. These patients showed significantly worse treatment satisfaction, even after accounting for improvements in myelopathy and QOL. As such, in patients who experience higher preoperative pain, multidisciplinary approaches for residual paresthesia, including medications for neuropathic pain, might lead to greater clinical satisfaction. LEVEL OF EVIDENCE: 3.

Factors Predicting the Final Diagnosis in Image-Guided Percutaneous Needle Biopsy for Suspected Spinal Tumors.

In cases of suspected spinal tumors on imaging studies, a biopsy is often necessary for establishing the diagnosis. Predictive factors for tumors or malignancies may help in scheduling biopsies or avoiding unnecessary ones. However, there have been few studies on determining these factors. We aimed to determine the factors associated with the final diagnosis in cases requiring spinal biopsy. This study included 117 patients who underwent image-guided (fluoroscopy- or computed tomography [CT]-guided) needle biopsy of the spine. Data on patient demographic, pathological diagnoses, and final diagnoses were retrospectively collected from the medical records. The imaging features and location of lesions were also evaluated on CT and magnetic resonance imaging. Furthermore, factors related to tumors or malignancies were analyzed. The diagnostic accuracy of biopsy was 94.0%, and there was no difference in the diagnostic accuracy between the fluoroscopic and CT-guided biopsies. Sixty-six and fifty-six patients were diagnosed with spinal tumors and malignant tumors, respectively. Multivariate analysis revealed that a history of malignant tumors and the presence of pedicle lesions and/or extravertebral lesions were related factors for both tumors or malignancy in the final diagnosis. These findings can help determine the necessity for or timing of biopsy in patients with suspected spinal tumors.

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.

Risk Factors for Poor Outcome after Palliative Surgery for Metastatic Spinal Tumors.

Palliative surgery is performed to improve the quality of life of patients with spinal metastases. However, it is sometimes difficult to achieve the expected results because the patient's condition, and risk factors related to poor outcomes have not been well elucidated. This study aimed to evaluate the functional outcomes and investigate the risk factors for poor outcomes after palliative surgery for spinal metastasis. We retrospectively reviewed the records of 117 consecutive patients who underwent palliative surgery for spinal metastases. Neurological and ambulatory statuses were evaluated pre- and post-operatively. Poor outcomes were defined as no improvement or deterioration in functional status or early mortality, and the related risk factors were analyzed using multivariate logistic regression analysis. The results showed neurological improvement in 48% and ambulatory improvement in 70% of the patients with preoperative impairment, whereas 18% of the patients showed poor outcomes. In the multivariate analysis, low hemoglobin levels and low revised Tokuhashi scores were identified as risk factors for poor outcomes. The present results suggest that anemia and low revised Tokuhashi scores are related not only to life expectancy but also to functional recovery after surgery. Treatment options should be carefully selected for the patients with these factors.

Deep Learning Algorithm for Identifying Cervical Cord Compression Due to Degenerative Canal Stenosis on Radiography.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: Validate the diagnostic accuracy of a deep-learning algorithm for cervical cord compression due to degenerative canal stenosis on radiography. SUMMARY OF BACKGROUND DATA: The diagnosis of degenerative cervical myelopathy is often delayed, resulting in improper management. Screening tools for suspected degenerative cervical myelopathy would help identify patients who require detailed physical evaluation. MATERIALS AND METHODS: Data from 240 patients (120 with cervical stenosis on magnetic resonance imaging and 120 age and sex-matched controls) were randomly divided into training (n = 198) and test (n = 42) data sets. The deep-learning algorithm, designed to identify the suspected stenosis level on radiography, was constructed using a convolutional neural network model called EfficientNetB2, and radiography and magnetic resonance imaging data from the training data set. The accuracy and area under the curve of the receiver operating characteristic curve were calculated for the independent test data set. Finally, the number of correct diagnoses was compared between the algorithm and 10 physicians using the test cohort. RESULTS: The diagnostic accuracy and area under the curve of the deep-learning algorithm were 0.81 and 0.81, respectively, in the independent test data set. The rate of correct responses in the test data set was significantly higher for the algorithm than for the physician's consensus (81.0% vs . 66.2%; P = 0.034). Furthermore, the accuracy of the algorithm was greater than that of each individual physician. CONCLUSIONS: We developed a deep-learning algorithm capable of suggesting the presence of cervical spinal cord compression on cervical radiography and highlighting the suspected levels on radiographic imaging when cord compression is identified. The diagnostic accuracy of the algorithm was greater than that of spine physicians. LEVEL OF EVIDENCE: Level IV.

A decision tree analysis to predict clinical outcome of minimally invasive lumbar decompression surgery for lumbar spinal stenosis with and without coexisting spondylolisthesis and scoliosis.

BACKGROUND CONTEXT: Implementing machine learning techniques, such as decision trees, known as prediction models that use logical construction diagrams, are rarely used to predict clinical outcomes. PURPOSE: To develop a clinical prediction rule to predict clinical outcomes in patients who undergo minimally invasive lumbar decompression surgery for lumbar spinal stenosis with and without coexisting spondylolisthesis and scoliosis using a decision tree model. STUDY DESIGN/SETTING: A retrospective analysis of prospectively collected data. PATIENT SAMPLE: This study included 331 patients who underwent minimally invasive surgery for lumbar spinal stenosis and were followed up for ≥2 years at 1 institution. OUTCOME MEASURES: Self-report measures: The Japanese Orthopedic Association (JOA) scores and low back pain (LBP)/leg pain/leg numbness visual analog scale (VAS) scores. Physiologic measures: Standing sagittal spinopelvic alignment, computed tomography, and magnetic resonance imaging results. METHODS: Low achievement in clinical outcomes were defined as the postoperative JOA score at the 2-year follow-up <25 points. Univariate and multiple logistic regression analysis and chi-square automatic interaction detection (CHAID) were used for analysis. RESULTS: The CHAID model for JOA score <25 points showed spontaneous numbness/pain as the first decision node. For the presence of spontaneous numbness/pain, sagittal vertical axis ≥70 mm was selected as the second decision node. Then lateral wedging, ≥6° and pelvic incidence minus lumbar lordosis (PI-LL) ≥30° followed as the third decision node. For the absence of spontaneous numbness/pain, sex and lateral olisthesis, ≥3mm and American Society of Anesthesiologists physical status classification system score were selected as the second and third decision nodes. The sensitivity, specificity, and the positive predictive value of this CHAID model was 65.1, 69.8, and 64.7% respectively. CONCLUSIONS: The CHAID model incorporating basic information and functional and radiologic factors is useful for predicting surgical outcomes.

Less-invasive decompression procedures can reduce risk of reoperation for lumbar spinal stenosis with diffuse idiopathic skeletal hyperostosis extended to the lumbar segment: analysis of two retrospective cohorts.

PURPOSE: Clinical outcomes after decompression procedures are reportedly worse for lumbar spinal stenosis (LSS) with diffuse idiopathic skeletal hyperostosis (DISH), especially DISH extended to the lumbar segment (L-DISH). However, no studies have compared the effect of less-invasive surgery versus conventional decompression techniques for LSS with DISH. The purpose of this study was to compare the long-term risk of reoperation after decompression surgery focusing on LSS with L-DISH. METHODS: This study compared open procedure cohort (open conventional fenestration) and less-invasive procedure cohort (bilateral decompression via a unilateral approach) with ≥ 5 years of follow-up. After stratified analysis by L-DISH, patients with L-DISH were propensity score-matched by age and sex. RESULTS: There were 57 patients with L-DISH among 489 patients in the open procedure cohort and 41 patients with L-DISH among 297 patients in the less-invasive procedure cohort. The reoperation rates in L-DISH were higher in the open than less-invasive procedure cohort for overall reoperations (25% and 7%, p = 0.026) and reoperations at index levels (18% and 5%, p = 0.059). Propensity score-matched analysis in L-DISH demonstrated that open procedures were significantly associated with increased overall reoperations (hazard ratio [HR], 6.18; 95% confidence interval [CI], 1.37-27.93) and reoperations at index levels (HR, 4.80; 95% CI, 1.04-22.23); there was no difference in reoperation at other lumbar levels. CONCLUSIONS: Less-invasive procedures had a lower risk of reoperation, especially at index levels for LSS with L-DISH. Preserving midline-lumbar posterior elements could be desirable as a decompression procedure for LSS with L-DISH.

Periostin increased by mechanical stress upregulates interleukin-6 expression in the ligamentum flavum.

Ligamentum flavum (LF) hypertrophy is a major cause of lumbar spinal canal stenosis. Although mechanical stress is thought to be a major factor involved in LF hypertrophy, the exact mechanism by which it causes hypertrophy has not yet been fully elucidated. Here, changes in gene expression due to long-term mechanical stress were analyzed using RNA-seq in a rabbit LF hypertrophy model. In combination with previously reported analysis results, periostin was identified as a molecule whose expression fluctuates due to mechanical stress. The expression and function of periostin were further investigated using human LF tissues and primary LF cell cultures. Periostin was abundantly expressed in human hypertrophied LF tissues, and periostin gene expression was significantly correlated with LF thickness. In vitro, mechanical stress increased gene expressions of periostin, transforming growth factor-ß1, α-smooth muscle actin, collagen type 1 alpha 1, and interleukin-6 (IL-6) in LF cells. Periostin blockade suppressed the mechanical stress-induced gene expression of IL-6 while periostin treatment increased IL-6 gene expression. Our results suggest that periostin is upregulated by mechanical stress and promotes inflammation by upregulating IL-6 expression, which leads to LF degeneration and hypertrophy. Periostin may be a pivotal molecule for LF hypertrophy and a promising therapeutic target for lumbar spinal stenosis.

Machine-learning-based approach for nonunion prediction following osteoporotic vertebral fractures.

PURPOSE: An osteoporotic vertebral fracture (OVF) is a common disease that causes disabilities in elderly patients. In particular, patients with nonunion following an OVF often experience severe back pain and require surgical intervention. However, nonunion diagnosis generally takes more than six months. Although several studies have advocated the use of magnetic resonance imaging (MRI) observations as predictive factors, they exhibit insufficient accuracy. The purpose of this study was to create a predictive model for OVF nonunion using machine learning (ML). METHODS: We used datasets from two prospective cohort studies for OVF nonunion prediction based on conservative treatment. Among 573 patients with acute OVFs exceeding 65 years in age enrolled in this study, 505 were analyzed. The demographic data, fracture type, and MRI observations of both studies were analyzed using ML. The ML architecture utilized in this study included a logistic regression model, decision tree, extreme gradient boosting (XGBoost), and random forest (RF). The datasets were processed using Python. RESULTS: The two ML algorithms, XGBoost and RF, exhibited higher area under the receiver operating characteristic curves (AUCs) than the logistic regression and decision tree models (AUC = 0.860 and 0.845 for RF and XGBoost, respectively). The present study found that MRI findings, anterior height ratio, kyphotic angle, BMI, VAS, age, posterior wall injury, fracture level, and smoking habit ranked as important features in the ML algorithms. CONCLUSION: ML-based algorithms might be more effective than conventional methods for nonunion prediction following OVFs.

Prevalence, risk factors, and potential symptoms of hyponatremia after spinal surgery in elderly patients.

Old age and spinal surgery significantly increase the risk of postoperative hyponatremia. However, detailed analyses of postoperative hyponatremia after spinal surgery in elderly patients are lacking. Therefore, we retrospectively reviewed the records of 582 consecutive patients aged > 60 years who underwent spinal surgery to evaluate the frequency, risk factors, and symptoms of postoperative hyponatremia after spinal surgery in the elderly population. Postoperative hyponatremia was defined as a postoperative blood sodium level < 135 meq/L at postoperative day (POD)1, POD3, and/or after POD6. A total of 92 (15.8%) patients showed postoperative hyponatremia. On a multivariate analysis, a diagnosis of a spinal tumor/infection, decompression and fusion surgery, and lower preoperative sodium levels were significant independent factors of postoperative hyponatremia (p = 0.014, 0.009, and < 0.001, respectively). In total, 47/92 (51%) cases could have been symptomatic; vomiting was noted in 34 cases (37%), nausea in 19 cases (21%), headache in 14 cases (15%), and disturbances in consciousness, including delirium, in ten cases (21%); all incidences of these symptoms were significantly higher in elderly patients with postoperative hyponatremia than in the matched control group without postoperative hyponatremia (p < 0.05, respectively). Additionally, the length of stay was 2 days longer in patients than in the matched controls (p = 0.002).

Change in Physical and Mental Quality-of-Life between the Short- and Mid-Term Periods after Cervical Laminoplasty for Cervical Spondylotic Myelopathy: A Retrospective Cohort Study with Minimum 5 Years Follow-up.

The mid-term surgical outcomes of cervical spondylotic myelopathy (CSM), evaluated using the cervical Japanese Orthopedic Association (cJOA) score, are reported to be satisfactory. However, there remains room for improvement in quality-of-life (QOL), especially after short-term follow-up. We aimed to demonstrate changes in mental and physical QOL between short- and mid-term follow-ups and determine the predictive factors for deterioration of QOL. In this retrospective cohort study, 80 consecutive patients underwent laminoplasty for CSM. The outcome measures were Short Form-36 Physical Component Summary (PCS), Mental Component Summary (MCS), and cJOA scores. PCS and MCS scores were compared at the 2- and 5-year postoperative time points. Additionally, a multivariate logistic regression model was used to identify the predictive factors for deterioration. Significant factors in the logistic regression analysis were analyzed using receiver-operating characteristic curves. The results showed that MCS scores did not deteriorate after 2 years postoperatively (p = 0.912). Meanwhile, PCS significantly declined between 2 and 5 years postoperatively (p = 0.008). cJOA scores at 2 years postoperatively were significantly associated with PCS deterioration at 2-year follow-up. In conclusion, only physical QOL might show deterioration after short-term follow-up. Such deterioration is likely in patients with a cJOA score <13.0 at 2 years postoperatively.

Associations between physical function, falls, and the fear of falling among older adults participating in a community-based physical exercise program: A longitudinal multilevel modeling study.

OBJECTIVES: Exercises that target muscle strength, balance, and gait prevent falls in older people. Moreover, exercise may reduce fear of falling by improving physical function. Many studies have examined the risk factors for falls and fear of falling separately. However, few studies have examined the associations between physical function, falls, and fear of falling simultaneously. This study aimed to identify the key physical functions influencing falls and fear of falling. DESIGN: Longitudinal observational study SETTING AND PARTICIPANTS: This study included 2,397 older adults (women: 82.8%, mean age: 74.3 ± 8.0 years) who participated in community-based physical exercise. METHODS: Physical functions such as muscle strength, balance, gait speed, and flexibility were measured regularly during the program. A questionnaire regarding falls and fear of falling was also administered simultaneously. Multilevel modeling was used to investigate the association between physical function and falls and fear of falling. RESULTS: The prevalence of falls and fear of falling at enrolment were 27.1% and 49.8%, respectively. Statistical analyses revealed that (1) falls were significantly associated with balance, age, fall history, fear of falling, and duration of participation; (2) fear of falling was significantly associated with muscle strength, balance, gait speed, age, and fall history. Long-term participation was significantly associated with an improvement in balance. CONCLUSIONS AND IMPLICATIONS: The risk factors for falls and fear of falling were different. Our research showed the importance of including balance training in all prevention programs.

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.

Improvements in Mental Well-Being and its Predictive Factors in Patients who Underwent Cervical versus Lumbar Decompression Surgery.

INTRODUCTION: Mental well-being is essential for patient satisfaction. Therefore, a better understanding of the changes in the mental well-being of patients following spinal surgery can be useful to surgeons. We compared the 2-year postoperative change in the mental well-being of patients who underwent cervical and lumbar decompression surgery. Additionally, the predictive factors for improvement in mental well-being associated with both methods were evaluated. METHODS: The patients who underwent spinal decompression surgery and were followed >2 years postoperatively were enrolled (lumbar cohort: n=111, cervical cohort: n=121). The 36-item Short-Form Health Survey (SF-36) mental component summary (MCS) was set as the mental well-being parameter, and the minimal clinically important difference (MCID) was defined as 4.0. After adjusting the cervical and lumbar cohorts using propensity scores, the improvements in the MCS were compared between the groups using a mixed-effect model. To identify predictors for improvements, the correlation between the MCS changes and preoperative clinical scores was evaluated. Subsequently, multivariate linear regression was applied, which included variables with p<0.10 in the former analysis as explanatory variables, and the change of MCS as the objective variable. RESULTS: There were no significant differences in the MCS improvement between the adjusted cervical and lumbar cohorts; 47% and 49%, respectively, had MCS improvement score >MCIDs. However, predictors for the improvement were different between the two cohorts: SF-36 Social functioning in cervical surgery and lower back pain and SF-36 Role physical in lumbar surgery. CONCLUSIONS: Although there was no significant difference in the improvement in the mental well-being between patients who underwent either cervical or lumbar decompression surgery, less than half of the patients in both groups achieved a meaningful improvement. Preoperative back pain and personal activity were independent predictors in the lumbar cohort, while social functioning was the only predictor in the cervical cohort. Level of evidence: III.

Incidence of postoperative progressive segment degeneration at decompression and adjacent segments after minimally invasive lumbar decompression surgery: a 5-year follow-up study.

OBJECTIVE: There are several reported studies on the incidence of adjacent segment disease (ASD) after lumbar fusion surgery; however, the incidence of ASD after decompression surgery has not been well studied. In this study the authors aimed to investigate the incidence of progressive segment degeneration (PSD) at the decompression and adjacent segments 5 years after minimally invasive lumbar decompression surgery. METHODS: We investigated data from 168 patients (mean age, 69.5 ± 9.2 years) who underwent bilateral microscopic or microendoscopic decompression surgery via a unilateral approach and were followed up for more than 5 years. Outcomes were self-reported visual analog scale (VAS) scores for low-back pain, leg pain, and leg numbness and physician-assessed Japanese Orthopaedic Association (JOA) scores for back pain. Changes in the disc height and movement of the adjacent lumbar segments were compared using preoperative and 5-year postoperative lateral full-length standing whole-spine radiographic images. PSD was defined as loss of disc height > 3 mm and progression of anterior or posterior slippage > 3 mm. The incidence and clinical impact of PSD were investigated. RESULTS: The mean JOA score improved significantly in all patients from 13.4 points before surgery to 24.1 points at the latest follow-up (mean recovery rate 67.8%). PSD at the decompression site was observed in 43.5% (73/168) of the patients. The proportions of patients with loss of disc height > 3 mm and slippage progression were 16.1% (27/168) and 36.9%, respectively (62/168: 41 anterior and 21 posterior). The proportion of patients with PSD at the adjacent segment was 20.5% (35/168), with 5.4% (9/168) of the patients with loss of disc height > 3 mm and 16.0% (27/168: 13 anterior and 14 posterior) with slippage progression. There was no significant difference in the clinical outcomes between patients with and those without PSD. CONCLUSIONS: Radiological ASD was observed even in the case of decompression surgery alone. However, there was no correlation with symptom deterioration, measured by the VAS and JOA scores.