Inner and outer penetrating spinal cord injuries lead to distinct overground walking in mice.

Spinal cord injury (SCI) is a devastating mechanical trauma. Although locomotion of model animals that mimic contusion SCI was actively examined, locomotion after penetrating SCI caused by sharp objects was not extensively studied. Severity of walking difficulty after partial transection of the spinal cord including penetrating SCI likely depends on the regions affected. Therefore, we compared beam walking and overground walking between mice after penetrating SCI at inner spinal cord region and mice with the injury at the outer region. Mice with the both penetrating SCIs did not display changes in beam walking. When appearance and movements of hindlimbs during overground walking was rated using Basso Mouse Scale for locomotion (BMS), however, mice with inner penetrating SCI showed low score shortly after the SCI. However, the score became high at later time points, as seen in contusion SCI mice. By contrast, BMS score did not decrease shortly after the outer penetrating SCI. However, the score became low 3 weeks after the SCI. As quantitative values during overground walking, movement duration in an open field were shorter at 1 day after the two penetrating SCIs. However, slower moving speed and fewer number of movement at 1 day were specific to mice with inner and outer penetrating SCIs, respectively. Moreover, BMS score was correlated with walking distance in open field only in mice with inner penetrating SCI. Thus, inner and outer penetrating SCI cause difficulty in overground walking with different severity and progress.

Usefulness of the preoperative thoracic inlet angle in comparison to the T1 slope for predicting cervical kyphosis after laminoplasty.

PURPOSE: Thoracic inlet angle (TIA) is a sagittal radiographic parameter with a constant value regardless of posture and is significantly correlated with the sagittal balance of the cervical spine. However, the practical use of TIA has not been studied. This study aimed to investigate the usefulness of the preoperative TIA for predicting the development of kyphotic deformity after cervical laminoplasty in comparison to the preoperative T1 slope (T1S). METHODS: A total of 98 patients who underwent cervical laminoplasty without preoperative kyphotic alignment were included (mean age, 73.7 years; 41.8% female). Radiography was evaluated before surgery and at the 2-year follow-up examination. The cervical sagittal parameters were measured on standing radiographs, and the TIA was measured on T2-weighted MRI in a supine position. Cervical alignment with a C2-C7 angle of ≥ 0° was defined as lordosis, and that with an angle of < 0° was defined as kyphosis. RESULTS: Postoperative kyphosis occurred in 11 patients (11.2%). Preoperatively, the kyphosis group showed significantly lower values in the T1S (23.5° vs. 30.3°, p = 0.034) and TIA (76.1° vs. 81.8°, p = 0.042). We performed ROC curve analysis to clarify the impact of the preoperative TIA and T1S on kyphotic deformity after laminoplasty. The optimal cutoff angles for TIA and T1S were 68° and 19°, respectively, with similar diagnostic accuracy. CONCLUSION: This study demonstrated the clinical utility of the preoperative TIA for predicting the risk of postoperative kyphotic deformity after cervical laminoplasty. These findings suggest the importance of the preoperative assessment of thoracic inlet alignment in cervical spine surgery.

Risk factors for early mortality in elderly patients with unstable isolated C2 odontoid fracture treated with halo-vest or surgery.

The aim of this study was to compare in-hospital mortality of three procedures -halo-vest immobilization, anterior spinal fixation (ASF), and posterior spinal fixation (PSF)- in the treatment of elderly patients with isolated C2 odontoid fracture. We extracted data for elderly patients who were admitted with C2 odontoid fracture and treated with at least one of the three procedures (halo-vest immobilization, ASF, or PSF) during hospitalization. We conducted a generalized propensity score-based matching weight analysis to compare in-hospital mortality among the three procedures. We further investigated independent risk factors for in-hospital death. The study involved 891 patients (halo-vest, n = 463; ASF, n = 74; and PSF, n = 354) with a mean age of 78 years. In-hospital death occurred in 45 (5.1%) patients. Treatment type was not significantly associated with in-hospital mortality. Male sex (odds ratio 2.98; 95% confidence interval 1.32-6.73; p = 0.009) and a Charlson comorbidity index of ≥ 3 (odds ratio 9.18; 95% confidence interval 3.25-25.92; p < 0.001) were independent risk factors for in-hospital mortality. In conclusion, treatment type was not significantly associated with in-hospital mortality in elderly patients with isolated C2 odontoid fracture. Halo-vest immobilization can help to avoid adverse events in patients with C2 odontoid fracture who are considered less suitable for surgical treatment.

Trends in cervical laminoplasty and 30-day postoperative complications: 10-year results from a retrospective, multi-institutional study of 1095 patients.

PURPOSE: This study aimed to investigate the recent 10-year trends in cervical laminoplasty and 30-day postoperative complications. METHODS: This retrospective multi-institutional cohort study enrolled patients who underwent laminoplasty for cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament. The primary outcome was the occurrence of all-cause 30-day complications. Trends were investigated and compared in the early (2008-2012) and late (2013-2017) periods. RESULTS: Among 1095 patients (mean age, 66 years; 762 [70%] male), 542 and 553 patients were treated in the early and late periods, respectively. In the late period, patients were older at surgery (65 years vs. 68 years), there were more males (66% vs. 73%), and open-door laminoplasty (50% vs. 69%) was the preferred procedure, while %CSM (77% vs. 78%) and the perioperative JOA scores were similar to the early period. During the study period, the rate of preservation of the posterior muscle-ligament complex attached to the C2/C7-spinous process (C2, 89% vs. 93%; C7, 62% vs. 85%) increased and the number of laminoplasty levels (3.7 vs. 3.1) decreased. While the 30-day complication rate remained stable (3.9% vs. 3.4%), C5 palsy tended to decrease (2.4% vs. 0.9%, P = 0.059); superficial SSI increased significantly (0% vs. 1.3%, P = 0.015), while the decreased incidence of deep SSI did not reach statistical significance (0.6% vs. 0.2%). CONCLUSIONS: From 2008 to 2017, there were trends toward increasing age at surgery and surgeons' preference for refined open-door laminoplasty. The 30-day complication rate remained stable, but the C5 palsy rate halved.

Radiographic Predictors of Subaxial Subluxation After Atlantoaxial Fusion.

STUDY DESIGN: A retrospective study. OBJECTIVE: The aim of this study was to clarify preoperative radiographic predictors associated with the development of subaxial subluxation (SAS) after surgery. BACKGROUND: The incidence of atlantoaxial fusion for atlantoaxial instability has been increasing. SAS can develop after surgery despite atlantoaxial fusion with the optimal C1-C2 angle. We hypothesized that preoperative discordant angular contribution in the upper and subaxial cervical spine is associated with the occurrence of postoperative SAS. MATERIALS AND METHODS: Patients who underwent surgery for atlantoaxial instability with a minimum 5-year follow-up and control participants were included. The O-C2 angle, C2 slope (C2S), C2-C7 cervical lordosis (CL), and T1 slope (T1S) were measured. We focused on the angular contribution ratio in the upper cervical spine to the whole CL, and the preoperative C2/T1S ratio was defined as the ratio of C2S to T1S. RESULTS: Twenty-seven patients (SAS=11, no-SAS=16; mean age, 60.7 y old; 77.8% female; mean follow-up duration, 6.8 y) and 23 demographically matched control participants were enrolled. The SAS onset was at 4.7 postoperative years. Preoperatively, the O-C2 angle, C2-C7 CL, and T1S were comparable between the SAS, no-SAS, and control groups. The preoperative C2S and C2/T1S ratio were smaller in the SAS group than in the no-SAS or control group (C2S, 11.0 vs. 18.4 vs. 18.7 degrees; C2/T1S ratio, 0.49 vs. 0.77 vs. 0.78, P <0.05). The receiver operating characteristic curve analysis demonstrated that the C2/T1S ratio had higher specificity and similar sensitivity as a predictor of postoperative SAS than C2S (specificity: 0.90 vs. 0.87; sensitivity: 0.73 vs. 0.73). The estimated cutoff values of the C2S and C2/T1S ratio were 14 degrees and 0.58, respectively. CONCLUSIONS: The preoperative C2/T1S ratio was closely associated with postoperative SAS. Patients with a C2/T1S ratio <0.58 were at a high risk of SAS after atlantoaxial fusion. LEVEL OF EVIDENCE: Level 4.

Late-Onset Esophageal Perforation After Salvage Anterior Cervical Spine Surgery in a Patient With Systemic Sclerosis.

Systemic sclerosis (SSc) is a systemic, immune-mediated disease characterized by abnormal cutaneous and organ-based fibrosis that results in progressive organ dysfunction including the esophagus. We herein report our experience of a patient with SSc who underwent salvage anterior cervical spine surgery that led to late-onset esophageal perforation. A 57-year-old female had progressive cervical kyphosis after laminoplasty for cervical spondylotic myelopathy. We performed anterior cervical discectomy and fusion using a stand-alone cage. Despite prolonged use of a neck collar, migration of the anterior cage was noted three months after surgery. Rapid progression of kyphotic deformity prompted us to perform revision surgery of circumferential cervical correction. However, conventional posterior surgery was precluded due to the extremely poor condition of her neck, including severely sclerotic skin and atrophic muscles. To address this, she underwent a posterior fusion with the closed technique and C4-C5 corpectomy and bone grafting using a low-profile anterior plate. One year after the surgery, CT and routine upper gastrointestinal endoscopy (UGE) showed no evidence of esophagus injury. She remained asymptomatic thereafter. Over three years after her last surgery, however, follow-up CT incidentally revealed an abnormal air leak around the anterior plate. UGE demonstrated large esophagus perforation with the exposed metal plate. As she had already been on parenteral nutrition due to the disease progression of SSc, we decided not to remove the implant. Potential esophagus perforation after anterior cervical spine surgery, even years later, should be considered regardless of the patient's symptoms, such as chest pain and dysphagia. Spine surgeons need to be cognizant of the fragility of the esophagus, especially in patients with SSc. For patients with SSc, posterior reconstruction alone is recommended as a relatively safe option, even with a suboptimal skin condition.

Impact of the preoperative nutritional status on postoperative kyphosis in geriatric patients undergoing cervical laminoplasty.

PURPOSE: This study aimed to determine the association of preoperative malnutrition with an increased risk of cervical kyphosis after laminoplasty in geriatric patients with cervical spondylotic myelopathy (CSM). METHODS: Geriatric patients who underwent cervical laminoplasty were included. Malnutrition was defined as a geriatric nutritional risk index < 98 before surgery. The C2-7 angle and the global alignment parameters were analyzed on standing radiographs. The postoperative kyphosis was defined as a C2-7 angle < 0° during a 2-year follow-up. RESULTS: Ninety patients without preoperative kyphotic alignment were enrolled (mean age, 73.5 years old; 41.1% female). Twenty-one patients (23.3%) had malnutrition status (74.2 years old). Preoperatively, the global alignment parameters were comparable between the malnutrition and normal nutrition groups (SVA, 43.3 mm vs. 42.4 mm; T1S, 29.7° vs. 28.4°; TPA, 21.4° vs. 17.8°), with no significant difference in the C2-7 angle (15.1° vs. 15.2°). At 2 years postoperatively, the malnutrition group showed a significantly lower C2-7 angle than the normal nutrition group (9.3° vs. 15.8°, P = 0.03). Postoperative kyphosis was more prevalent in the malnutrition group (33.3% vs. 7.2%, P = 0.005). The preoperative nutritional status and C2-7 angle were independent predictors of postoperative kyphosis. The predictive C2-7 angles differed by preoperative nutritional status (malnutrition group, 11°; normal nutrition group, 7°). CONCLUSION: Among geriatric CSM patients, preoperative malnutrition was closely associated with the increased occurrence of cervical kyphosis after laminoplasty. Our results underscore the importance of preoperative nutritional assessment and management in geriatric populations undergoing cervical spine surgery, as malnutrition is a perioperative modifiable risk factor.

A simple scoring of beam walking performance after spinal cord injury in mice.

Precise evaluation of motor functions using simple and reproducible tests for mouse models of spinal cord injury (SCI) are required. Overground walking of SCI mice has been tested by Basso Mouse Scale for locomotion (BMS). In contrast, only a few works quantify walking performances of SCI mice on narrow beams, a different task. Here, we established a novel scoring system using a single beam walking apparatus for SCI mice. The scoring system uses binary judgments of values such as retention, moving forward and reaching the goal on a beam for rating. In addition, high score was given to SCI mouse when the mouse efficiently used hindlimbs for locomotion on the beam. A high rate of concordance of the score derived from positions of hindlimbs between two observers was obtained. Mice displayed the lowest total score on the beam immediately after the SCI, then the score gradually increased like time course of BMS score. Furthermore, the total scores reflected gradation of severity of SCI in 2 strains of mice. The beam walking score proved to be strongly correlated with that of BMS score, indicating that performances between overground walking and beam walking are partly correlated in SCI mice. Collectively, the novel scoring system offers an opportunity to easily evaluate motor performances of mice with SCI.

Effect of Intraoperative Tranexamic Acid on Perioperative Major Hemorrhage Requiring Transfusion in Patients Undergoing Elective Spine Surgery: A Propensity Score-Matched Analysis Using a National Inpatient Database.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: This study aimed to examine whether the use of intravenous TXA in elective spine surgery is associated with reduced perioperative massive hemorrhage requiring transfusion. METHODS: We extracted all patients who underwent decompression with or without fusion surgery for the cervical, thoracic, and lumbar spine between April 2012 and March 2019. The primary outcome was the occurrence of massive hemorrhage requiring transfusion, defined as at least 560 mL of blood transfusion within 2 days of spine surgery or the requirement of additional blood transfusion from 3-7 days postoperatively. Secondary outcomes were the occurrence of thrombotic complications (pulmonary embolism, acute coronary syndrome, and stroke) and postoperative hematoma requiring additional surgery. RESULTS: We identified 83,821 eligible patients, with 9747 (12%) patients in the TXA group. Overall, massive hemorrhage requiring transfusion occurred in 781 (.9%) patients. Propensity score matching yielded 8394 pairs. In the matched cohort, the TXA group had a lower proportion of massive hemorrhage requiring transfusion than the control group (.7% vs 1.1%; P = .002). There was no significant difference in the occurrence of thrombotic complications and postoperative hematoma requiring additional surgery between both groups. The multivariable regression analysis also showed that the use of TXA was associated with significantly lower proportions of massive hemorrhage requiring transfusion (odds ratio, .62; 95% confidence interval, .43-.90; P = .012). CONCLUSIONS: In this analysis using real-world data, TXA use in elective spinal surgery was associated with reduced perioperative massive hemorrhage requiring transfusion without increasing thrombotic complications. LEVEL OF EVIDENCE: Prognostic Level Ⅲ.

Risk factors for severe lower extremity ischemia following venoarterial extracorporeal membrane oxygenation: an analysis using a nationwide inpatient database.

Objectives: Venoarterial extracorporeal membrane oxygenation is increasingly being used as a life-saving modality in critically ill patients. Despite its necessity, severe lower extremity ischemia associated with venoarterial extracorporeal membrane oxygenation remains a potentially devastating complication. We aimed to investigate the incidence and risk factors for severe lower extremity ischemia requiring fasciotomy or amputation following venoarterial extracorporeal membrane oxygenation. Methods: All patients who received venoarterial extracorporeal membrane oxygenation during hospitalization were identified in a Japanese national inpatient database from July 1, 2010 to March 31, 2018. The primary outcome was occurrence of severe lower extremity ischemia that required fasciotomy or amputation. We used cause-specific proportional hazard models to examine the associations between potential risk factors and outcomes. We also performed a competing-risk analysis to estimate the cause-specific HR for severe lower extremity ischemia using a multivariable competing-risk Cox proportional hazard model with adjustment for potential risk factors. Results: A total of 29 231 patients who underwent venoarterial extracorporeal membrane oxygenation during hospitalization were identified. Of these, 98 patients (0.3%) had lower extremity ischemia requiring fasciotomy or amputation. The young group (≤18 years) had a significantly higher proportion of severe lower extremity ischemia cases than the adult (19-59 years) and elderly (≥60 years) groups (1.4%, 0.5%, and 0.2%, respectively; p<0.001). In a multivariable competing-risk Cox proportional hazards regression model, younger age (HR 3.06; 95% CI 1.33 to 7.02; p<0.008) and consciousness disturbance on admission (HR 2.53; 95% CI 1.60 to 3.99; p<0.001) were significantly associated with higher likelihood of severe lower extremity ischemia. Conclusion: In this study using a nationwide database, younger age and consciousness disturbance on admission were associated with higher risk of severe lower extremity ischemia following venoarterial extracorporeal membrane oxygenation. Level of evidence: Level Ⅲ-prognostic and epidemiological.

The Association Between the Rotator Cuff Status and the Severity and Recovery of Weakness in the Shoulder Abductor Strength in a Case of Proximal Type Cervical Spondylotic Amyotrophy.

STUDY DESIGN: Case series study. OBJECTIVE: We aimed to clarify the prevalence of rotator cuff tear (RCT), and the association between RCT and the severity and prognosis in patients with proximal type cervical spondylotic amyotrophy (CSA). METHODS: We retrospectively analyzed 35 proximal type CSA patients who were treated conservatively. The following data was collected: age, rotator cuff status on MRI, manual muscle test (MMT) score of shoulder abductor and biceps brachii muscles both at the first visit and final follow-up. We investigated the prevalence of RCT and the association between the rotator cuff status, and the severity and recovery of upper extremity weakness in patients with proximal type CSA. RESULTS: Of the 35 patients, 21 had an RCT on MRI, indicating that the prevalence of RCT in patients with proximal type CSA was 60%. An age-adjusted analysis showed that the presence of RCT was significantly associated with the MMT score of the shoulder abductor muscles both at the first visit and at the final follow-up. The presence of RCT was significantly associated with the recovery of the shoulder abductor muscles. The size of the RCT was negatively correlated with the MMT score of the shoulder abductor muscles at the final follow-up. The size of the RCT was independently correlated with the change of the MMT score of the shoulder abductor muscles. CONCLUSION: RCT was detected in >50% in patients with proximal type CSA, and the presence and severity of RCT can be used as prognostic factors for proximal type CSA patients who are treated conservatively.

Increased Cervical Spinal Instability is Associated With the Development of Proximal-type Cervical Spondylotic Amyotrophy.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: We aimed to clarify the clinical relationship between the etiology of proximal-type cervical spondylotic amyotrophy (CSA) and cervical sagittal alignment and instability. SUMMARY OF BACKGROUND DATA: Although several researchers have discussed hypotheses regarding the etiology of CSA, the trigger and mechanism underlying the onset remain unclear. METHODS: We retrospectively analyzed 52 proximal-type CSA patients (CSA group) and 60 control patients (Control group). The following data were collected: age; sex; cervical lordosis (CL); T1 slope (TS); TS-CL; C2-7 sagittal vertical axis (SVA) on x-ray in the neutral position; flexion angle; extension angle and range of motion (ROM) of C3/4, C4/5 and C5/6; and C3/4, C4/5 and C5/6 instability (translation of >3 mm for adjacent segmental segments) on dynamic x-ray. RESULTS: Compared with the Control group, the CSA group was associated with an older age (mean age, 67.6 vs. 61.1 years' old, P= 0.029) and male sex (78.8% vs. 50.0%, P= 0.002). In the CSA group, the radiographic parameters showed smaller C4/5 and C5/6 extension angles and C5/6 ROM values and a greater C3/4 flexion angle than the Control group. Furthermore, compared with the Control group, the CSA group was associated with C3/4 instability (13.5% vs. 3.3%, P= 0.049) and C4/5 (21.2% vs. 3.3%, P = 0.003). A logistic regression analysis, with adjusting for the age and sex, showed that the C3/4 flexion angle (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.08- 1.40, P =0.002), C3/4 instability (OR, 7.3; 95% CI 1.25-42.96, P =0.027) and C4/5 instability (OR, 8.1; 95% CI, 1.56-42.19, P = 0.012) were independent risk factors of CSA. CONCLUSION: This study suggested that a wide C3/4 flexion angle and high C3/4 or C4/5 spinal instability were closely associated with the etiology of proximal-type CSA.

Cervical Kyphosis due to Neurofibromatosis Type 1 Treated by Circumferential Spinal Fusion using an Autologous Vascularized free Fibula Followed by Teriparatide Administration: A Case Report.

Introduction: Cervical kyphosis is sometimes observed in neurofibromatosis Type 1 (NF-1). If NF-1-associated cervical deformity is progressive, surgical intervention is needed to prevent further deterioration of the deformity. The rate of nonunion after spinal fusion is high in NF-1, especially dystrophic NF-1. Case Report: Cervical kyphosis is sometimes observed in neurofibromatosis Type 1 (NF-1). If NF-1-associated cervical deformity is progressive, surgical intervention is needed to prevent further deterioration of the deformity. The rate of nonunion after spinal fusion is high in NF-1, especially dystrophic NF-1. Conclusion: We administered the teriparatide after spinal fusion surgery for NF-1-associated cervical deformity and obtained complete bony fusion. The administration of teriparatide may be useful to achieve complete bone fusion in patients with NF-1-associated cervical deformity.

Risk Factors for Throwing-Related Shoulder and Elbow Pain in Adolescent Baseball Players: A Prospective Study of Physical and Developmental Factors.

BACKGROUND: Throwing-related shoulder and elbow pain continues to be reported among adolescent baseball players. Few prospective studies have specifically examined the association between throwing-related shoulder and elbow pain and physical and developmental changes. PURPOSE: To evaluate the changes in physical and developmental characteristics during 1 year with respect to throwing-related shoulder and elbow pain in adolescent baseball players. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This 1-year prospective follow-up study investigated 164 baseball players aged 7 to 13 years. Player data (age, height, weight, field position, and pitch count), lower extremity muscle tightness, and range of motion (ROM) of the shoulder, elbow, and hip joints were assessed during the 2016 and 2017 preseason medical examinations. After the 2016 season, the participants completed questionnaires related to throwing-related shoulder and elbow pain, defined as an inability to play for ≥1 week because of elbow or shoulder difficulties. For study participants with and without throwing-related shoulder or elbow pain during the 2016 season, we conducted univariate and multivariate logistic regression analysis to identify risk factors for throwing-related shoulder or elbow pain. RESULTS: Overall, 21 players (12.8%) reported a shoulder pain episode, 56 players (34.1%) had an elbow pain episode, and 70 players (42.7%) reported having experienced shoulder and/or elbow pain during the 2016 season. In multivariate logistic regression analysis, (1) shoulder pain was associated with 2016 preseason height (odds ratio [OR], 1.06; 95% CI, 1.01-1.11; P = .01) and change in dominant-side elbow extension ROM from 2016 to 2017 (OR, 1.12; 95% CI, 1.02-1.24; P = .02); (2) elbow pain was associated with change in weight from 2016 to 2017 (OR, 1.21; 95% CI, 1.04-1.41; P = .014); and (3) throwing-related shoulder and/or elbow pain was associated with greater 2016 preseason height (OR, 1.04; 95% CI, 1.003-1.68; P = .03) and an increase in height from 2016 to 2017 (OR, 1.17; 95% CI, 1.01-1.35; P = .03). CONCLUSION: Our results indicated that adolescent baseball players who were taller in the preseason and those with an increase in height over the 1-year study period faced significant risks for developing throwing-related shoulder and/or elbow pain.

Angiomatous Meningioma in the Craniocervical Junction.

INTRODUCTION: Spinal angiomatous meningioma arising in the craniocervical junction has not been reported. Case Presentation. A 68-year-old man presented to our hospital with pain in the back and left leg. He showed slight motor weakness in his upper extremities. Magnetic resonance imaging revealed a mass with marked enhancement in the craniocervical junction. Computed tomography angiography showed feeding vessels arising from the right vertebral artery. Preoperative embolization of the feeding vessels was performed to reduce intraoperative bleeding. Gross total resection of the tumor was achieved by debulking and piecemeal resection. The tumor attachment to the dura mater was also resected (Simpson grade 1 resection). A histopathological examination confirmed the diagnosis of an angiomatous meningioma. The patient's symptoms improved shortly after surgery. CONCLUSIONS: We achieved gross total resection of spinal angiomatous meningioma arising in the craniocervical junction. A preoperative evaluation and embolization of the feeding arteries may help prevent massive intraoperative bleeding.

Clinical features and early post-operative complications of isolated C2 odontoid fractures: a retrospective analysis using a national inpatient database in Japan.

PURPOSE: To examine the clinical features and post-treatment complications in patients with isolated C2 odontoid fractures. METHODS: We extracted data for all patients who were admitted with C2 odontoid fractures from the Japanese Diagnosis Procedure Combination database between July 2010 and March 2017. We then compared the post-treatment complications during hospitalization according to treatment types: conservative treatment (with or without use of halo-vest) and surgery (anterior or posterior spinal fixation). RESULTS: A total of 3167 patients (1533 men, 1634 women; mean age, 70 years) with isolated C2 odontoid fractures were identified, including 1124 patients (35%) aged ≥ 80 years. Among the total patients, 2476 (78%) received conservative treatment (with halo-vest, 728; without halo-vest, 1748). The remaining 691 patients (22%) underwent surgery (anterior surgery, 129; posterior surgery, 556; combined surgery, 6). There were no differences between the conservative treatment and surgery groups in baseline characteristics and preexisting comorbid conditions except for age (71 vs. 69 years, p = 0.042). In-hospital death occurred in 136 patients (4.3%). There was no significant difference in in-hospital mortality between the two groups (overall, conservative treatment 4.6% vs. surgery 3.0%, p = 0.066; age ≥ 80 years, conservative treatment 7.2% vs. surgery 5.4%, p = 0.34). Use of halo-vest was not associated with increased mortality (with halo-vest 3.7% vs. without halo-vest 5.0%, p = 0.15). CONCLUSION: The great majority of isolated odontoid fractures occurred in elderly patients. Conservative treatment and surgery had similarly low in-hospital mortality. Use of halo-vest was not associated with an increase in mortality.

Paraplegia due to Thoracic Mobile Schwannoma after Myelography.

INTRODUCTION: Spinal mobile tumors are very rare. We herein report a case of paraplegia caused by migration and incarceration of thoracic mobile schwannoma after myelography. Case Presentation. A 25-year-old man who had weakness and numbness in both his legs also had pain radiating to the back that was induced by back flexion or extension and jumping. Magnetic resonance imaging (MRI) showed an intradural extramedullary lesion at the T10 and T11 levels. Myelography was performed but discontinued due to his back and lower limb pain. Computed tomography after myelography revealed a rostrally migrated intradural mass with a discrepancy in the exact location in comparison to the MRI findings. He underwent a second lumbar puncture and drained the cerebrospinal fluid (CSF) to aid the spinal cord, because the symptoms gradually worsened and led to paraplegia. After the drainage of the CSF, his symptoms were immediately resolved. The day after myelography, he underwent complete resection of the tumor with the diagnosis of schwannoma. One year after the surgery, he had been working despite having hyperreflexia in his lower limbs with no weakness or sensory disturbance. CONCLUSION: Severe neurological deficits associated with spinal cord damage can occur due to migration of mobile tumors.