Predictive biomarkers of ossification progression and bone metabolism dynamics in patients with cervical ossification of the posterior longitudinal ligament.

PURPOSE: This study aimed to establish biomarkers to predict the progression of ossification by examining ossification volume and bone metabolism dynamics in patients with ossification of the posterior longitudinal ligament (OPLL). METHODS: We assessed OPLL progression using computed tomography-based three-dimensional (3D) image analysis and examined bone metabolism dynamics in 107 patients with OPLL (men, 72; women, 35; mean age, 63.6 years). The volume of OPLL was calculated twice during the follow-up period, and OPLL progression was evaluated by the annual rate of ossification increase. Bone metabolism dynamics were assessed by routine blood tests and analysis of various serum biomarkers (including 25-hydroxyvitamin D, intact parathyroid hormone, fibroblast growth factor 23, intact N-terminal propeptide of type 1, tartrate-resistant acid phosphatase isoform 5b, sclerostin, and Dickkopf-1) and bone mineral density (BMD). Patients were classified into the progression (P) or non-progression (NP) group according to the annual rate of increase in previous 3D image analyses, and associated factors between these groups were compared. RESULTS: The P and NP groups consisted of 29 patients (23 men and 6 women) and 78 patients (49 men and 29 women), respectively. Univariate analysis revealed significant differences in terms of age, body mass index, serum phosphorus, serum sclerostin, and BMD. In multivariate analysis, age, serum phosphorus, and serum sclerostin were identified as independent factors associated with OPLL progression. CONCLUSION: Younger age, hypophosphatemia, and high serum sclerostin are risk factors for OPLL progression. Serum phosphorus and sclerostin could serve as important biomarkers for predicting ossification progression.

Deep learning-based prediction model for postoperative complications of cervical posterior longitudinal ligament ossification.

PURPOSE: Postoperative complication prediction helps surgeons to inform and manage patient expectations. Deep learning, a model that finds patterns in large samples of data, outperform traditional statistical methods in making predictions. This study aimed to create a deep learning-based model (DLM) to predict postoperative complications in patients with cervical ossification of the posterior longitudinal ligament (OPLL). METHODS: This prospective multicenter study was conducted by the 28 institutions, and 478 patients were included in the analysis. Deep learning was used to create two predictive models of the overall postoperative complications and neurological complications, one of the major complications. These models were constructed by learning the patient's preoperative background, clinical symptoms, surgical procedures, and imaging findings. These logistic regression models were also created, and these accuracies were compared with those of the DLM. RESULTS: Overall complications were observed in 127 cases (26.6%). The accuracy of the DLM was 74.6 ± 3.7% for predicting the overall occurrence of complications, which was comparable to that of the logistic regression (74.1%). Neurological complications were observed in 48 cases (10.0%), and the accuracy of the DLM was 91.7 ± 3.5%, which was higher than that of the logistic regression (90.1%). CONCLUSION: A new algorithm using deep learning was able to predict complications after cervical OPLL surgery. This model was well calibrated, with prediction accuracy comparable to that of regression models. The accuracy remained high even for predicting only neurological complications, for which the case number is limited compared to conventional statistical methods.

The impact of diabetes mellitus on spinal fracture with diffuse idiopathic skeletal hyperostosis: A multicenter retrospective study.

BACKGROUND: Patients with diffuse idiopathic skeletal hyperostosis (DISH) are susceptible to spinal column injuries with neurological deterioration. Previous studies indicated that the prevalence of diabetes mellitus (DM) in patients with DISH was higher than that in patients without DISH. This study investigates the impact of DM on surgical outcomes for spinal fractures in patients with DISH. METHODS: We retrospectively evaluated 177 spinal fractures in patients with DISH (132 men and 45 women; mean age, 75 ± 10 years) who underwent surgery from a multicenter database. The subjects were classified into two groups according to the presence of DM. Perioperative complications, neurological status by Frankel grade, mortality rate, and status of surgical site infection (SSI) were compared between the two groups. RESULTS: DM was present in 28.2% (50/177) of the patients. The proportion of men was significantly higher in the DM group (DM group: 86.0% vs. non-DM group: 70.1%) (p = 0.03). The overall complication rate was 22.0% in the DM group and 19.7% in the non-DM group (p = 0.60). Poisson regression model revealed that SSI was significantly associated with DM (DM group: 10.0% vs. non-DM group: 2.4%, Relative risk: 4.5) (p = 0.048). Change in neurological status, mortality rate, instrumentation failure, and nonunion were similar between both groups. HbA1c and fasting blood glucose level (SSI group: 7.2% ± 1.2%, 201 ± 67 mg/dL vs. non-SSI group: 6.6% ± 1.1%, 167 ± 47 mg/dL) tended to be higher in patients with SSI; however, there was no significant difference. CONCLUSIONS: In spinal fracture in patients with DISH, although DM was an associated factor for SSI with a relative risk of 4.5, DM did not negatively impact neurological recovery. Perioperative glycemic control may be useful for preventing SSI because fasting blood glucose level was high in patients with SSI.

The characteristics of the young patients with cervical ossification of the posterior longitudinal ligament of the spine: A multicenter cross-sectional study.

BACKGROUND: Ossification of the posterior longitudinal ligament of the spine (OPLL) is characterized by heterotopic bone formation in the posterior longitudinal ligament of the spine. Although the patients with OPLL are more common in the 60s and 70s, we know that there are markedly young patients (e.g., early 40s). However, to the best of our knowledge, there is few reports characterize young patients with cervical OPLL in terms of the imaging features, subjective symptoms, and ADL problems. METHODS: This is the multicenter cross-sectional study. Two hundred and thirty-seven Japanese symptomatic patients with cervical OPLL confirmed by standard X-rays collected from 16 institutions belonging to the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament formed by the Japanese Ministry of Health, Labor and Welfare were recruited. Whole spine CT data as well as demographic data such as age, gender, patients-based evaluations, and the 36-item Short Form Health Survey (SF-36) were evaluated. RESULTS: Young group (≦ 45 years old) consisted of 23 patients (8 females and 15 males), accounting for 9.7% of the total. Their characteristics were high body mass index (BMI), significant involvement of trauma in the onset and deterioration of symptoms, and the predominance of thoracic OPLL. The patient-based evaluations did not show a significant difference between the young and non-young groups, or between the genders in the young group except for bodily pain (BP) of SF-36. Female patients in young group had significantly lower BP score of SF-36 than that of male in young group. CONCLUSIONS: Characteristics of young patients with cervical OPLL were high BMI, significant involvement of trauma in the onset and deterioration of symptoms, lower BP score of SF-36 in female, and the predominance of thoracic OPLL.

Significance of long corrective fusion to the ilium for physical function in patients with adult spinal deformity.

BACKGROUND: We aimed to investigate the impact of long corrective fusion to the ilium on the physical function in elderly patients with adult spinal deformity and its correlation with spinopelvic parameters and health-related quality of life outcomes. METHODS: We included 60 female patients who underwent long corrective fusion from T9 or T10 to the pelvis for adult spinal deformities (mean age of 69.8 years, range 55-78 years). The radiographic parameters, health-related quality of life outcomes using the Scoliosis Research Society Outcome Instrument-22 and physical function assessments were reviewed preoperatively and at 1-year postoperatively. RESULTS: All spinopelvic parameters, except for thoracolumbar kyphosis, and all domains of the Scoliosis Research Society Outcome Instrument-22 significantly improved at 1-year postoperatively (p < 0.0001). Physical function results, including those for one-leg standing time, timed up-and-go test, and 6-min walk tests, significantly improved at 1-year postoperatively (p < 0.005). Based on forward stepwise multivariate logistic regression, the predicted timed up-and-go test and 6-min walk test outcomes at 1-year postoperatively were as follows: timed up-and-go test, 7.8 + 0.47 × preoperative timed up-and-go test - 0.21 × 1-year postoperative grasping power +0.015 × 1-year postoperative C1 sagittal vertical axis (R2 = 0.6209, p < 0.0001); 6-min walk test, 309.2-9.1 × body mass index + 11.6 × 1-year postoperative grasping power + 3.3 × 1-year postoperative thoracolumbar kyphosis - 0.59 × 1-year postoperative C1 sagittal vertical axis (R2 = 0.4409, p < 0.0001). CONCLUSIONS: Corrective long fusion surgery for adult spinal deformity in normalizing sagittal alignment improves trunk balance and gait performance. Postoperative physical function depends on the preoperative physical performance status and skeletal muscle status; thus, preoperative interventions for improved physical function are recommended.

Risk factors for delayed diagnosis of spinal fracture associated with diffuse idiopathic skeletal hyperostosis: A nationwide multiinstitution survey.

BACKGROUND: Patients with DISH are susceptible to spinal fractures and subsequent neurological impairment, including after minor trauma. However, DISH is often asymptomatic and fractures may have minimal symptoms, which may lead to delayed diagnosis. The purpose of this study was to identify risk factors for delayed diagnosis of spinal fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: The subjects were 285 patients with DISH surgically treated at 18 medical centers from 2005 to 2015. Cause of injury, imaging findings, neurological status at the times of injury and first hospital examination, and the time from injury to diagnosis were recorded. A delayed diagnosis was defined as that made >24 h after injury. RESULTS: Main causes of injury were minor trauma due to a fall from a standing or sitting position (51%) and high-energy trauma due to a fall from a high place (29%) or a traffic accident (12%). Delayed diagnosis occurred in 115 patients (40%; 35 females, 80 males; mean age 76.0 ± 10.4 years), while 170 (60%; 29 females, 141 males; mean age 74.6 ± 12.8 years) had early diagnosis. Delayed group had a significantly higher rate of minor trauma (n = 73, 63% vs. n = 73, 43%), significantly more Frankel grade E (intact neurological status) cases at the time of injury (n = 79, 69% vs. n = 73, 43%), and greater deterioration of Frankel grade from injury to diagnosis (34% vs. 8%, p < 0.01). In multivariate analysis, a minor trauma fall (OR 2.08; P < 0.05) and Frankel grade E at the time of injury (OR 2.29; P < 0.01) were significantly associated with delayed diagnosis. CONCLUSION: In patients with DISH, it is important to keep in mind the possibility of spinal fracture, even in a situation in which patient sustained only minor trauma and shows no neurological deficit. This is because delayed diagnosis of spinal fracture can cause subsequent neurological deterioration.

Detailed features and prognostic factors of twenty-three patients with drop finger caused by cervical radiculopathy: a retrospective multicentre study.

PURPOSE: It has been reported that C7 and C8 nerve root impairment can cause drop finger; however, the clinical characteristics of each injured nerve root and post-operative outcomes remain unclear. This study aimed to investigate the detailed features and surgery-related prognostic factors of drop finger caused by cervical radiculopathy. METHODS: We retrospectively investigated the clinical characteristics, paralysis patterns and surgery-related prognostic factors of 23 patients with drop finger caused by cervical radiculopathy who underwent posterior cervical foraminotomy. We classified paralysis into three patterns based on the fingers predominantly exhibiting extensor digitorum communis (EDC) muscle weakness: index finger side-dominant, middle and ring fingers-dominant and little finger side-dominant. RESULTS: The aetiologies were cervical disc hernia (CDH) in ten patients, cervical spondylotic radiculopathy (CSR) in eight and both CDH and CSR in five. The levels of the decompressed root were C7 in one patient, C8 in 11 and both C7 and C8 in 11. Scapular pain was frequently observed as the initial symptom (78%), especially in patients with only C8 nerve root disorder (91%). Drop finger recovered to a score of ≥ 3 on manual muscle testing in 17 patients; patients with the little finger side-dominant pattern tended to have poor recoveries. Patients with CDH improved significantly than those with CSR or both CDH and CSR (p < 0.05). CONCLUSIONS: Good surgical recovery of drop finger can be expected in patients with CDH and in those with index fingers-dominant and middle and ring fingers-dominant patterns.

Short- versus long-segment posterior spinal fusion with vertebroplasty for osteoporotic vertebral collapse with neurological impairment in thoracolumbar spine: a multicenter study.

BACKGROUND: Vertebroplasty with posterior spinal fusion (VP + PSF) is one of the most widely accepted surgical techniques for treating osteoporotic vertebral collapse (OVC). Nevertheless, the effect of the extent of fusion on surgical outcomes remains to be established. This study aimed to evaluate the surgical outcomes of short- versus long-segment VP + PSF for OVC with neurological impairment in thoracolumbar spine. METHODS: We retrospectively collected data from 133 patients (median age, 77 years; 42 men and 91 women) from 27 university hospitals and their affiliated hospitals. We divided patients into two groups: a short-segment fusion group (S group) with 2- or 3-segment fusion (87 patients) and a long-segment fusion group (L group) with 4- through 6-segment fusion (46 patients). Surgical invasion, clinical outcomes, local kyphosis angle (LKA), and complications were evaluated. RESULTS: No significant differences between the two groups were observed in terms of neurological recovery, pain scale scores, and complications. Surgical time was shorter and blood loss was less in the S group, whereas LKA at the final follow-up and correction loss were superior in the L group. CONCLUSION: Although less invasiveness and validity of pain and neurological relief are secured by short-segment VP + PSF, surgeons should be cautious regarding correction loss.

Effect of bisphosphonates or teriparatide on mechanical complications after posterior instrumented fusion for osteoporotic vertebral fracture: a multi-center retrospective study.

BACKGROUND: The optimal treatment of osteoporosis after reconstruction surgery for osteoporotic vertebral fractures (OVF) remains unclear. In this multicentre retrospective study, we investigated the effects of typically used agents for osteoporosis, namely, bisphosphonates (BP) and teriparatide (TP), on surgical results in patients with osteoporotic vertebral fractures. METHODS: Retrospectively registered data were collected from 27 universities and affiliated hospitals in Japan. We compared the effects of BP vs TP on postoperative mechanical complication rates, implant-related reoperation rates, and clinical outcomes in patients who underwent posterior instrumented fusion for OVF. Data were analysed according to whether the osteoporosis was primary or glucocorticoid-induced. RESULTS: A total of 159 patients who underwent posterior instrumented fusion for OVF were included. The overall mechanical complication rate was significantly lower in the TP group than in the BP group (BP vs TP: 73.1% vs 58.2%, p = 0.045). The screw backout rate was significantly lower and the rates of new vertebral fractures and pseudoarthrosis tended to be lower in the TP group than in the BP group. However, there were no significant differences in lumbar functional scores and visual analogue scale pain scores or in implant-related reoperation rates between the two groups. The incidence of pseudoarthrosis was significantly higher in patients with glucocorticoid-induced osteoporosis (GIOP) than in those with primary osteoporosis; however, the pseudoarthrosis rate was reduced by using TP. The use of TP also tended to reduce the overall mechanical complication rate in both primary osteoporosis and GIOP. CONCLUSIONS: The overall mechanical complication rate was lower in patients who received TP than in those who received a BP postoperatively, regardless of type of osteoporosis. The incidence of pseudoarthrosis was significantly higher in patients with GIOP, but the use of TP reduced the rate of pseudoarthrosis in GIOP patients. The use of TP was effective to reduce postoperative complications for OVF patients treated with posterior fusion.

Flexibility of the thoracic curve and three-dimensional thoracic kyphosis can predict pulmonary function in nonoperatively treated adult patients with adolescent idiopathic scoliosis.

BACKGROUND: Although several radiographic predictors for pulmonary function in adolescent patients have been reported, those in adult patients remain unclear. Therefore, we aimed to investigate the associations between spinal deformity and pulmonary function in nonoperatively treated adult patients with adolescent idiopathic scoliosis (AIS). METHODS: Of 319 patients treated nonoperatively for AIS, 90 (average age, 40.0 ± 6.5 years) underwent both full-length standing radiographs and pulmonary function test. Standard two-dimensional (2-D) radiographic measurements were performed. Three-dimensional thoracic kyphosis (3-D TK) was calculated from 2-D standing radiograph data using a validated formula: 3-D TK (°) = 18.1 + 0.81 × (2-D TK) + 0.54 × (Cobb angle of thoracic curve). 3-D TK was defined as the sum of segmental kyphosis between T5 and T12, which eliminates the overestimation of TK in 2-D measurements due to rotational deformity. Bivariable correlation analysis, followed by a stepwise multiple linear regression analysis, was performed. RESULTS: The average Cobb angle of the thoracic curve at the time of survey was 49.4° ± 14.6° with flexibility of 37.5% ± 18.2%. Thoracic curve magnitude, flexibility, apical vertebral rotation and translation, and 3-D TK were significantly correlated with percent-predicted forced vital capacity (%FVC) and expiratory volume in 1 s (%FEV1.0). Stepwise multiple regression analysis showed that curve flexibility and 3-D TK were significant, independent predictors of %FVC (R2 = 0.358) and %FEV1.0 (R2 = 0.335), curve flexibility having a greater impact (standardized coefficient > 0.45) than 3-D TK (<0.32). CONCLUSIONS: Our results indicate that nonoperatively treated patients with AIS should be recommended to maintain flexibility of the thoracic curve to prevent future pulmonary impairment. Moreover, 3-D TK is another independent predictor of pulmonary function, which suggests that segmental sagittal alignment is a component of deformity correction to focus on.

Three-dimensional morphological analysis of cervical foraminal stenosis using dynamic flexion-extension computed tomography images.

BACKGROUND: Morphological features of foraminal stenosis in cervical spondylotic radiculopathy and the adequate extent of facet resection in posterior cervical foraminotomy remain uncertain. Herein, we evaluated quantitatively foraminal widths in cervical spondylotic radiculopathy on dynamic flexion-extension computed tomography using a novel three-dimensional analysis method and determined the extent of facet resection in posterior cervical foraminotomy. METHODS: Seventeen patients undergoing posterior cervical foraminotomy for cervical spondylotic radiculopathy were evaluated. A neuroforamen three-dimensional model was built from preoperative images of flexion-extension computed tomography myelography, and an ordinary cervical spine coordinate system and an original neuroforaminal coordinate system, were established. In the neuroforaminal coordinate system, minimum areas perpendicular to the long axis by the slices from inlet to outlet of neuroforamen and narrowest foraminal width in a slice of minimum area were measured. The location of the narrowest region from inlet of the foramen was calculated. Ratios of minimum and sufficient facet resection were obtained from the location of the narrowest region in the neuroforaminal coordinate system. RESULTS: The narrowest foraminal widths (flexion/extension) in the cervical spine coordinate system and the neuroforaminal coordinate system were 2.9/2.3 and 2.6/1.9 mm, respectively. The mean values of the location of the narrowest region (flexion/extension) were 0.27/0.22 and 0.50/0.45 mm, respectively, and the narrowest region in the neuroforaminal coordinate system was located on the outer side than in the cervical spine coordinate system (p < 0.001). The ratios of minimum and sufficient facet resection were 23 ± 8% and 32 ± 9%, respectively. CONCLUSIONS: The narrowest regions both in flexion and extension are located at the middle of the foramen based on the neuroforaminal coordinate system. Ordinary evaluation of axial computed tomography images likely underestimates the extent of facet resection, whereas certain extent of facet resection does not exceed 50% in cases with single-level cervical spondylotic radiculopathy. STUDY DESIGN: A retrospective case control study.

Can posterior implant removal prevent device-related vertebral osteopenia after posterior fusion in adolescent idiopathic scoliosis? A mean 29-year follow-up study.

PURPOSE: To determine whether posterior implant removal prevents stress-shielding-induced vertebral osteopenia within the posterior fusion area in surgically treated patients with adolescent idiopathic scoliosis (AIS). METHODS: Eighteen patients with major thoracic AIS (mean age, 43.3 years; range, 32-56 years; mean follow-up, 28.8 years, range, 20-39 years) who underwent posterior spinal fusion (PSF) alone between 1973 and 1994 were included. Participants were divided into implant removal (group R, n = 10, mean interval until implant removal, 50 months) and implant non-removal groups (group NR, n = 8). Bone mineral density was evaluated using the Hounsfield units (HU) of the computed tomography image of the full spine. The HU values of the UIV-1 (one level below the uppermost instrumented vertebra), apex, LIV+1 (one level above the lowermost instrumented vertebra), and LIV-1 (one level below the lowermost instrumented vertebra; as a standard value) were obtained. Stress-shielding-induced osteopenia was assessed as the UIV-1/LIV-1, apex/LIV-1, and LIV+1/LIV-1 HU ratios (× 100). RESULTS: Overall (median, 25th-75th percentile), the apex (144.7, 108.6-176.0) and LIV+1 (159.4, 129.7-172.3) demonstrated lower HU values than LIV-1 (180.3, 149.2-200.2) (both comparisons, p < .05). Comparison of groups R and NR showed no significant differences in the scoliosis correction rate, bone mineral density of the proximal femur, the HU absolute values of all investigated vertebrae, or in the HU ratios of the investigated vertebrae to LIV-1. CONCLUSION: Instrumented PSF causes stress-shielding-induced osteopenia of the vertebral body within the fusion area in adulthood, which cannot be prevented by posterior implant removal, probably due to firm fusion mass formation. These slides can be retrieved under Electronic Supplementary Material.

Surgical outcomes of spinal fusion for osteoporotic thoracolumbar vertebral fractures in patients with Parkinson's disease: what is the impact of Parkinson's disease on surgical outcome?

BACKGROUND: To date, there have been little published data on surgical outcomes for patients with PD with thoracolumbar OVF. We conducted a retrospective multicenter study of registry data to investigate the outcomes of fusion surgery for patients with Parkinson's disease (PD) with osteoporotic vertebral fracture (OVF) in the thoracolumbar junction. METHODS: Retrospectively registered data were collected from 27 universities and their affiliated hospitals in Japan. In total, 26 patients with PD (mean age, 76 years; 3 men and 23 women) with thoracolumbar OVF who underwent spinal fusion with a minimum of 2 years of follow-up were included (PD group). Surgical invasion, perioperative complications, radiographic sagittal alignment, mechanical failure (MF) related to instrumentation, and clinical outcomes were evaluated. A control group of 296 non-PD patients (non-PD group) matched for age, sex, distribution of surgical procedures, number of fused segments, and follow-up period were used for comparison. RESULTS: The PD group showed higher rates of perioperative complications (p < 0.01) and frequency of delirium than the non-PD group (p < 0.01). There were no significant differences in the degree of kyphosis correction, frequency of MF, visual analog scale of the symptoms, and improvement according to the Japanese Orthopaedic Association scoring system between the two groups. However, the PD group showed a higher proportion of non-ambulators and dependent ambulators with walkers at the final follow-up (p < 0.01). CONCLUSIONS: A similar surgical strategy can be applicable to patients with PD with OVF in the thoracolumbar junction. However, physicians should pay extra attention to intensive perioperative care to prevent various adverse events and implement a rehabilitation regimen to regain walking ability.

Spinal fractures in patients with Diffuse idiopathic skeletal hyperostosis:A nationwide multi-institution survey.

BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) increases the spine's susceptibility to unstable fractures that can cause neurological deterioration. However, the detail of injury is still unclear. A nationwide multicenter retrospective study was conducted to assess the clinical characteristics and radiographic features of spinal fractures in patients with DISH. METHODS: Patients were eligible for this study if they 1) had DISH, defined as flowing ossification along the anterolateral aspect of at least four contiguous vertebral bodies, and 2) had an injury in the ankylosing spine. This study included 285 patients with DISH (221 males, 64 females; mean age 75.2 ± 9.5 years). RESULTS: The major cause of injury was falling from a standing or sitting position; this affected 146 patients (51.2%). Diagnosis of the fracture was delayed in 115 patients (40.4%). Later neurological deterioration by one or more Frankel grade was seen in 87 patients (30.5%). The following factors were significantly associated with neurological deficits: delayed diagnosis (p = 0.033), injury of the posterior column (p = 0.021), and the presence of ossification of the posterior longitudinal ligament (OPLL) (p < 0.001). The majority of patients (n = 241, 84.6%) were treated surgically, most commonly by conventional open posterior fixation (n = 199, 69.8%). Neurological improvement was seen in 20.0% of the conservatively treated patients, and in 47.0% of the patients treated surgically. CONCLUSIONS: Minor trauma could cause spinal fractures in DISH patients. Delayed diagnosis, injury of the posterior column, and the presence of OPLL were significantly associated with neurological deterioration. Patients with neurological deficits or unstable fractures should be treated by fixation surgery.

Surgical outcomes of spinal fusion for osteoporotic vertebral fracture in the thoracolumbar spine: Comprehensive evaluations of 5 typical surgical fusion techniques.

BACKGROUND: A consensus on the optimal surgical procedure for thoracolumbar OVF has yet to be reached due to the previous relatively small number of case series. The study was conducted to investigate surgical outcomes for osteoporotic vertebral fracture (OVF) in the thoracolumbar spine. METHODS: In total, 315 OVF patients (mean age, 74 years; 68 men and 247 women) with neurological symptoms who underwent spinal fusion with a minimum 2-year follow-up were included. The patients were divided into 5 groups by procedure: anterior spinal fusion alone (ASF group, n = 19), anterior/posterior combined fusion (APSF group, n = 27), posterior spinal fusion alone (PSF group, n = 40), PSF with 3-column osteotomy (3CO group, n = 92), and PSF with vertebroplasty (VP + PSF group, n = 137). RESULTS: Mean operation time was longer in the APSF group (p < 0.05), and intraoperative blood loss was lower in the VP + PSF group (p < 0.05). The amount of local kyphosis correction was greater in the APSF and 3CO groups (p < 0.05). Clinical outcomes were approximately equivalent among all groups. CONCLUSION: All 5 procedures resulted in acceptable neurological outcomes and functional improvement in walking ability. Moreover, they were similar with regard to complication rates, prevalence of mechanical failure related to the instrumentation, and subsequent vertebral fracture. Individual surgical techniques can be adapted to suit patient condition or severity of OVF.

Complications after spinal fixation surgery for osteoporotic vertebral collapse with neurological deficits: Japan Association of Spine Surgeons with ambition multicenter study.

BACKGROUND: There have been few reports on the incidence and risk factors of the complications after spinal fixation surgery for osteoporotic vertebral collapse (OVC) with neurological deficits. This study aimed to identify the incidence and risk factors of the complications after OVC surgery. METHODS: In this retrospective multicenter study, a total of 403 patients (314 women and 89 men; mean age 73.8 years) who underwent spinal fixation surgery for OVC with neurological deficits between 2005 and 2014 were enrolled. Data on patient demographics were collected, including age, sex, body mass index, smoking, steroid use, medical comorbidities, and surgical procedures. All postoperative complications that occurred within 6 weeks were recorded. Patients were classified into two groups, namely, complication group and no complication group, and risk factors for postoperative complications were investigated by univariate and multivariate analyses. RESULTS: Postoperative complications occurred in 57 patients (14.1%), and the most common complication was delirium (5.7%). In the univariate analysis, the complication group was found to be older (p = 0.039) and predominantly male (p = 0.049), with higher occurrence rate of liver disease (p = 0.001) and Parkinson's disease (p = 0.039) compared with the no-complication group. In the multivariate analysis, the significant independent risk factors were age (p = 0.021; odds ratio [OR] 1.051, 95% confidence interval [CI] 1.007-1.097), liver disease (p < 0.001; OR 8.993, 95% CI 2.882-28.065), and Parkinson's disease (p = 0.009; OR 3.636, 95% CI 1.378-9.599). CONCLUSIONS: Complications after spinal fixation surgery for OVC with neurological deficits occurred in 14.1%. Age, liver disease, and Parkinson's disease were demonstrated to be independent risk factors for postoperative complications.

Natural history of the ossification of cervical posterior longitudinal ligament: a three dimensional analysis.

PURPOSE: Three-dimensional (3D) imaging using computed tomography (CT) has made it possible to accurately evaluate ossification of the posterior longitudinal ligament (OPLL). Recently, we developed a novel technique to measure ossification volume using the 3D analysis. The purpose of this study was to investigate the natural course of OPLL and the risk factors for volume progression. METHODS: Forty-one patients (22 males and 19 females) diagnosed with cervical OPLL who had been non-surgically treated were included in this study. We evaluated clinical examination, radiological findings, and the volume of ossified lesions during at least 1-year intervals. Furthermore, we performed risk factor analysis for OPLL volume progression. RESULTS: The mean ossification volume was 2047.4 ± 1437.3 mm3 in the first examination and 2201.0 ± 1524.1 mm3 in the final examination, indicating a significant increase during the follow-up period (p < 0.001). The mean annual rate of lesion increase was 4.1 ± 2.7%. Univariate regression analysis demonstrated significant relationships between the annual rate of lesion increase and age (ß = -0.48; p = 0.001), body weight (BW) (ß = 0.36; p = 0.02), and body mass index (BMI) (ß = 0.35; p = 0.03). Furthermore, age was the only significant predictor of OPLL progression (R2 = 0.23; p = 0.001) in multivariate liner regression analysis. CONCLUSIONS: Younger age, higher BW, and higher BMI are predictors of OPLL progression. Younger age is the most significant predictor in non-surgically treated patients.

Characteristics of spinopelvic alignment in Parkinson's disease: Comparison with adult spinal deformity.

PURPOSE: The characteristics and pathogenesis of spinopelvic alignment in Parkinsons's disease (PD) patients-including differences compared to non-PD subjects and their relationships with the severity of PD-have not been clarified. The aim of this study was to investigate the characteristics of spinopelvic alignment in patients with PD. METHODS: Forty-eight PD patients complaining of chronic low back pain were included (PD group). The PD condition, determined using the Hoehn and Yahr (H&Y) stage and Unified Parkinson Disease Rating Scale (UPDRS) score; radiographic spinopelvic alignment; lumbar range of motion (ROM); and low back pain-related quality of life assessments were evaluated. Fifty age- and sex-matched patients with adult spinal deformities were included as controls (ASD group). RESULTS: The spinopelvic alignments of the PD/ASD groups demonstrated sagittal vertical axes of 120.9/106.3 mm and pelvic incidences of 49.7/52.9°, with no significant differences. Conversely, there were significant differences in the thoracic kyphosis (TK; 27.6/16.7°), lumbar lordosis (-22.7/-7.9°), and pelvic tilt (25.3/34.4°) (all, p < 0.05). With regard to correlations with the PD condition, the H&Y stage demonstrated significant correlations with the sagittal vertical axis, thoracolumbar kyphosis, and lumbar ROM (all, p < 0.05), and the UPDRS score tended to correlate with the TK and thoracolumbar kyphosis (both, p < 0.01). CONCLUSION: Characteristic spinal conditions in PD exist, with progressed PD condition causing stooped posture with increased thoracic or thoracolumbar kyphosis and decreased lumbar ROM; moreover, global sagittal malalignment progresses without sufficient compensatory mechanisms such as loss of TK and pelvic retroversion.

Hydrogen peroxide modulates synaptic transmission in ventral horn neurons of the rat spinal cord.

KEY POINTS: Excessive production of reactive oxygen species (ROS) is implicated in many central nervous system disorders; however, the physiological role of ROS in spinal ventral horn (VH) neurons remains poorly understood. We investigated how pathological levels of H2O2, an abundant ROS, regulate synaptic transmission in VH neurons of rats using a whole-cell patch clamp approach. H2O2 increased the release of glutamate and GABA from presynaptic terminals. The increase in glutamate release involved N-type voltage-gated calcium channels (VGCCs), ryanodine receptors (RyRs), and inositol trisphosphate receptors (IP3 Rs); the increase in GABA release, which inhibited glutamatergic transmission, involved IP3 R. Inhibiting N-type VGCCs and RyRs attenuates excitotoxicity resulting from increased glutamatergic activity while preserving the neuroprotective effects of GABA, and may represent a novel strategy for treating H2O2-induced motor neuron disorders resulting from trauma or ischaemia-reperfusion injury. Excessive production of reactive oxygen species (ROS) is a critical component of the cellular and molecular pathophysiology of many central nervous system (CNS) disorders, including trauma, ischaemia-reperfusion injury, and neurodegenerative diseases. Hydrogen peroxide (H2O2), an abundant ROS, modulates synaptic transmission and contributes to neuronal damage in the CNS; however, the pathophysiological role of H2O2 in spinal cord ventral horn (VH) neurons remains poorly understood, despite reports that these neurons are highly vulnerable to oxidative stress and ischaemia. This was investigated in the present study using a whole-cell patch clamp approach in rats. We found that exogenous application of H2O2 increased the release of glutamate from excitatory presynaptic terminals and γ-aminobutyric acid (GABA) from inhibitory presynaptic terminals. The increase of glutamate release was induced in part by an increase in Ca(2+) influx through N-type voltage-gated calcium channels (VGCCs) as well as by ryanodine receptor (RyR)- and inositol trisphosphate receptor-mediated Ca(2+) release from the endoplasmic reticulum (ER). In inhibitory presynaptic neurons, increased IP3 R-mediated Ca(2+) release from the ER increased GABAergic transmission, which served to rescue VH neurons from excessive release of glutamate from presynaptic terminals. These findings indicate that inhibiting N-type VGCCs or RyRs may attenuate excitotoxicity resulting from increased glutamatergic activity while preserving the neuroprotective effects of GABA, and may therefore represent a novel and targeted strategy for preventing and treating H2O2-induced motor neuron disorders.

Posterior instrumented fusion suppresses the progression of ossification of the posterior longitudinal ligament: a comparison of laminoplasty with and without instrumented fusion by three-dimensional analysis.

PURPOSE: There is no definitive evidence that additional instrumented fusion following laminoplasty suppresses the progression of ossification of the posterior longitudinal ligament (OPLL). Recently, we reported a novel method involving the creation of three-dimensional (3D) model from computed tomography images to measure the volume of OPLL accurately. The study aim was to evaluate whether laminoplasty with instrumented fusion suppresses the progression of OPLL in comparison with stand-alone laminoplasty by our novel 3D analysis. METHODS: The present study comprised of a group of 19 patients (14 men, five women) with OPLL treated with posterior decompression and fusion (PDF group), and a group of 22 patients (14 men, eight women) treated with laminoplasty alone (LP group). The volume of OPLL was evaluated three times during the follow-up period, and the volume change of OPLL was compared between the two groups. RESULTS: The PDF group (2.0 ± 1.7 %/year; range, -3.0 to 5.3) demonstrated lower annual rate of lesion increase compared to the LP group (7.5 ± 5.6 %/year; range, 1.0-19.2) (p < 0.001). In a notable thing, the annual rate of increase from the 2nd to the 3rd measurement significantly decreased compared with that from the 1st to the 2nd measurement in the PDF group (p < 0.05). CONCLUSION: This is the first study to prove a possible suppressant effect of additional posterior instrumented fusion on OPLL progression using novel 3D analysis.