Sequential neurological improvements after conservative treatment in patients with complete motor paralysis caused by cervical spinal cord injury without bone and disc injury.

OBJECTIVE This study investigated neurological improvements after conservative treatment in patients with complete motor paralysis caused by acute cervical spinal cord injury (SCI) without bone and disc injury. METHODS This study was retrospective. The authors evaluated neurological outcomes after conservative treatment of 62 patients with complete motor paralysis caused by cervical SCI without bone and disc injury within 72 hours after trauma. The sequential changes in their American Spinal Injury Association Impairment Scale (AIS) grades were reviewed at follow-up 24-72 hours, 1 week, and 1, 3, and 6 months after treatment. RESULTS Of the 31 patients with a baseline AIS grade of A, 2 (6.5%) patients improved to grade B, 5 (16.1%) improved to grade C, and 2 (6.5%) improved to grade D by the 6-month follow-up. The 22 (71.0%) patients who remained at AIS grade A 1 month after injury showed no neurological improvement at the 6-month follow-up. Of the 31 patients with a baseline AIS grade of B, 12 (38.7%) patients showed at least a 1-grade improvement at the 1-month follow-up; 11 (35.5%) patients improved to grade C and 16 (51.6%) patients improved to grade D at the 6-month follow-up. CONCLUSIONS Even in patients with complete motor paralysis caused by cervical SCI without bone and disc injury within 72 hours after trauma, approximately 30% of the patients with an AIS grade of A and 85% of the patients with an AIS grade B improved neurologically after conservative treatment. It is very important to recognize the extent of neurological improvement possible with conservative treatment, even for severe complete motor paralysis.

Sensitivity and specificity of the 'knee-up test' for estimation of the American Spinal Injury Association Impairment Scale in patients with acute motor incomplete cervical spinal cord injury.

STUDY DESIGN: A retrospective study. OBJECTIVE: Precise classification of the neurological state of patients with acute cervical spinal cord injury (CSCI) can be challenging. This study proposed a useful and simple clinical method to help classify patients with incomplete CSCI. SETTING: Spinal Injuries Centre, Japan. METHODS: The sensitivity and specificity of the 'knee-up test' were evaluated in patients with acute CSCI classified as American Spinal Injury Association Impairment Scale (AIS) C or D. The result is positive if the patient can lift the knee in one or both legs to an upright position, whereas the result is negative if the patient is unable to lift the knee in either leg to an upright position. The AIS of these patients was classified according to a strict computerised algorithm designed by Walden et al., and the knee-up test was tested by non-expert examiners. RESULTS: Among the 200 patients, 95 and 105 were classified as AIS C and AIS D, respectively. Overall, 126 and 74 patients demonstrated positive and negative results, respectively, when evaluated using the knee-up test. A total of 104 patients with positive results and 73 patients with negative results were classified as AIS D and AIS C, respectively. The sensitivity, specificity, positive predictive and negative predictive values of this test for all patients were 99.1, 76.8, 82.5 and 98.7, respectively. CONCLUSIONS: The knee-up test may allow easy and highly accurate estimation, without the need for special skills, of AIS classification for patients with incomplete CSCI.

A Safe Surgical Procedure for Old Distractive Flexion Injuries of the Subaxial Cervical Spine.

STUDY DESIGN: Retrospective review. PURPOSE: To describe a safe and effective surgical procedure for old distractive flexion (DF) injuries of the subaxial cervical spine. OVERVIEW OF LITERATURE: Surgical treatment is required in old cases when a progression of the kyphotic deformity and/or persistent neck pain and/or the appearance of new neurological symptoms are observed. Since surgical treatment is more complicated and dangerous in old cases than in acute distractive-flexion cases, the indications for surgery and the selection of the surgical procedure must be carefully conducted. METHODS: To identify a safe and effective surgical procedure, the procedure selected, reason(s) for its selection, and associated neurological complications were investigated in 13 patients with old cervical DF injuries. RESULTS: No neurological complications were observed in nine patients (DF stage 2 or 3) who underwent the anterior-posterior-anterior (A-P-A) method and two patients (DF stage 1) who underwent the posterior method. It was initially planned that two patients (DF stage 2) who underwent the P-A method would be treated using the Posterior method alone; however, anterior discectomy was added to the procedure after the development of a severe spinal cord disorder. CONCLUSIONS: The A-P-A method (anterior discectomy, posterior release and/or partial facetectomy, reduction and instrumentation, anterior bone grafting) is considered to be a suitable surgical procedure for old cervical DF injuries.

Kinematic Effects of Cervical Laminoplasty for Cervical Spondylotic Myelopathy on the Occipitoatlantoaxial Junction.

STUDY DESIGN: A retrospective evaluation of sagittal angular motion from cervical spinal flexion to extension. OBJECTIVE: To evaluate the kinematic effects of cervical laminoplasty for cervical spondylotic myelopathy (CSM) on the occipitoatlantoaxial junction. SUMMARY OF BACKGROUND DATA: The kinematic effects of cervical laminoplasty for CSM on the occipitoatlantoaxial junction remain controversial. METHODS: A total of 65 CSM patients who were treated with cervical laminoplasty ranging from the C3 to C7 vertebrae were included in the study. After surgery, all patients wore a Philadelphia collar for the first week and began cervical range of motion exercises as soon as possible. Functional plain radiographs were obtained preoperatively and at 1 and 3 years postoperatively. Sagittal angular motion from cervical spinal flexion to extension was measured using the Cobb technique at 7 cervical segments (Oc-C1, C1-C2, C2-C3, C3-C4, C4-C5, C5-C6, and C6-C7). We defined the contribution of each segment's mobility to the total angular mobility of the cervical spine as percent segmental mobility. RESULTS: Total cervical angular mobility significantly decreased after cervical laminoplasty. There were no significant differences in Oc-C2 angular mobility; however, C2-C7 angular mobility had significantly decreased by 3 years postoperatively. No significant differences in percent segmental mobility were observed at 1 year postoperatively except at the C3-C4 segment. By 3 years postoperatively, percent mobility at the Oc-C1 and C1-C2 segments had significantly increased, whereas that at the C3-C4 and C5-C6 segments had significantly decreased. CONCLUSIONS: Our results suggest that, although the contribution of occipitoatlantoaxial junctional mobility to total cervical mobility increases, dynamic mechanical stress to the occipitoatlantoaxial junction does not increase following laminoplasty, and no adjacent segmental disorder at the occipitoatlantoaxial junction was observed within 3 years postoperatively. We hypothesized that early removal of the cervical collar and early cervical range of motion exercises may contribute to these kinematic changes.

"Knee-up test" for easy detection of postoperative motor deficits following spinal surgery.

BACKGROUND CONTEXT: Neurologic motor deficit is a serious complication of spinal surgery. Early diagnosis of complications by neurologic examination immediately after spinal surgery is mandatory. However, patients cannot always cooperate with the physician in the very early stages of recovery. PURPOSE: The aim of the present study is to prospectively investigate the usefulness of the "knee-up test" for easy detection of postoperative motor deficits. STUDY DESIGN: A prospective clinical study was carried out. PATIENT SAMPLE: Patients with spinal disorder operated upon at a single institute were administered the knee-up test after an anesthesiologist had judged that endotracheal extubation was possible. OUTCOME MEASURES: The outcome measures were preoperative and postoperative Manual Muscle Testing. METHODS: A simple yet reliable method known as the "knee-up test" was developed to easily assess postoperative deficits before endotracheal extubation. When the patient's knee is passively lifted up and the patient is able to maintain this position in both legs, the result is negative, whereas when the patient is unable to maintain the knee in an upright position for one or both legs, the result is positive. The presently accepted criterion for a new-onset postoperative neurologic motor deficit is motor weakness leading to a decrease in function of at least two grades in more than one muscle function within 12 hours of spinal surgery, as evaluated by the Manual Muscle Testing. The association between the presence of new-onset motor deficits and the results of the knee-up test was prospectively investigated. RESULTS: Seventeen patients exhibited positive results when evaluated using the knee-up test, whereas 521 patients exhibited negative results. Sixteen of the patients with positive results were determined to have new-onset motor deficits, whereas no new-onset motor deficits were observed in the remaining patient. Of the 521 patients with negative knee-up test results, only 2 were determined to have new-onset motor deficits, whereas no new-onset motor deficits were observed in the remaining 519 patients. The sensitivity, specificity, positive predictive value, and negative predictive value were 88.9, 99.8, 94.1, and 99.6, respectively. CONCLUSIONS: The knee-up test may allow for early and easy detection of postoperative motor deficits with high probability in very early stages.

Clinical Influence of Cervical Spinal Canal Stenosis on Neurological Outcome after Traumatic Cervical Spinal Cord Injury without Major Fracture or Dislocation.

STUDY DESIGN: Retrospective case series. PURPOSE: To clarify the influence of cervical spinal canal stenosis (CSCS) on neurological functional recovery after traumatic cervical spinal cord injury (CSCI) without major fracture or dislocation. OVERVIEW OF LITERATURE: The biomechanical etiology of traumatic CSCI remains under discussion and its relationship with CSCS is one of the most controversial issues in the clinical management of traumatic CSCI. METHODS: To obtain a relatively uniform background, patients non-surgically treated for an acute C3-4 level CSCI without major fracture or dislocation were selected. We analyzed 58 subjects with traumatic CSCI using T2-weighted mid-sagittal magnetic resonance imaging. The sagittal diameter of the cerebrospinal fluid (CSF) column, degree of canal stenosis, and neurologic outcomes in motor function, including improvement rate, were assessed. RESULTS: There were no significant relationships between sagittal diameter of the CSF column at the C3-4 segment and their American Spinal Injury Association motor scores at both admission and discharge. Moreover, no significant relationships were observed between the sagittal diameter of the CSF column at the C3-4 segment and their neurological recovery during the following period. CONCLUSIONS: No relationships between pre-existing CSCS and neurological outcomes were evident after traumatic CSCI. These results suggest that decompression surgery might not be recommended for traumatic CSCI without major fracture or dislocation despite pre-existing CSCS.

A Study of Risk Factors for Tracheostomy in Patients With a Cervical Spinal Cord Injury.

STUDY DESIGN: A retrospective, consecutive case series. OBJECTIVE: To determine the risk factors for a tracheostomy in patients with a cervical spinal cord injury. SUMMARY AND BACKGROUND DATE: Respiratory status cannot be stabilized in patients with a cervical spinal cord injury (CSCI) for various reasons, so a number of these patients require long-term respiratory care and a tracheostomy. Various studies have described risk factors for a tracheostomy, but none have indicated a relationship between imaging assessment and the need for a tracheostomy. The current study used imaging assessment and other approaches to assess and examine the risk factors for a tracheostomy in patients with a CSCI. METHODS: Subjects were 199 patients who were treated at the Spinal Injuries Center within 72 hours of a CSCI over 8-year period. Risk factors for a tracheostomy were retrospectively studied. Patients were assessed in terms of 10 items: age, sex, the presence of a vertebral fracture or dislocation, ASIA Impairment Scale, the neurological level of injury (NLI), PaO2, PaCO2, the level of injury on magnetic resonance imaging (MRI), the presence of hematoma-like changes (a hypointense core surrounded by a hyperintense rim in T2-weighted images) on MRI, and the Injury Severity Score.Items were analyzed multivariate logistic regression, and P < 0.05 was considered to indicate a significant difference. RESULTS: Twenty-three of the 199 patients required a tracheostomy, accounting for 11.6% of patients with a CSCI. Univariate analyses of the risk factors for tracheostomy revealed significant differences for six items: age, Injury Severity Score, presence of fracture or dislocation, ASIA Impairment Scale A, NLI C4 or above, and MRI scans revealing hematoma-like changes. Multivariate logistic regression analyses revealed significant differences in terms of two items: NLI C4 or above and MRI scans revealing hematoma-like changes. Thirty patients had both an NLI C4 or above and MRI scans revealing hematoma-like changes. Of these, 17 (56.7%) required a tracheostomy. CONCLUSION: Patients with an NLI C4 or above and MRI scans revealing hematoma-like changes were likely to require a tracheostomy. An early tracheostomy should be considered for patients with both of these characteristics. LEVEL OF EVIDENCE: 3.

Risk factors for adjacent segment pathology requiring additional surgery after single-level spinal fusion: impact of pre-existing spinal stenosis demonstrated by preoperative myelography.

PURPOSE: We determined the incidence of and risk factors for clinical adjacent segment pathology (C-ASP) requiring additional surgeries among patients previously treated with one-segment lumbar decompression and fusion surgery. METHODS: We retrospectively analysed 161 consecutive patients who underwent one-segment lumbar decompression and fusion surgery for L4 degenerative spondylolisthesis. Patient age, sex, body mass index (BMI), facet orientation and tropism, laminar inclination angle, spinal canal stenosis ratio [on myelography and magnetic resonance imaging (MRI)], preoperative adjacent segment instability, arthrodesis type, pseudarthrosis, segmental lordosis at L4-5, and the present L4 slip were evaluated by a log-rank test using the Kaplan-Meier method. A multivariate Cox proportional-hazards model was used to analyse all factors found significant by the log-rank test. RESULTS: Of 161 patients, 22 patients (13.7 %) had additional surgeries at cranial segments located adjacent to the index surgery's location. Pre-existing canal stenosis ≥47 % at the adjacent segment on myelography, greater facet tropism, and high BMI were significant risk factors for C-ASP. The estimated incidences at 10 years postoperatively for each of these factors were 51.3, 39.6, and 32.5 %, and the risks for C-ASP were 4.9, 3.7, and, 3.1 times higher than their counterparts, respectively. Notably, spinal canal stenosis on myelography, but not on MRI, was found to be a significant risk factor for C-ASP (log-rank test P < 0.0001 and 0.299, respectively). CONCLUSIONS: Pre-existing spinal stenosis, greater facet tropism, and higher BMI significantly increased C-ASP risk. Myelography is a more accurate method for detecting latent spinal canal stenosis as a risk factor for C-ASP.

Radiological Outcome of Short Segment Posterior Instrumentation and Fusion for Thoracolumbar Burst Fractures.

STUDY DESIGN: Retrospective study. PURPOSE: To evaluate the radiological outcome of the surgical treatment of thoracolumbar burst fractures by using short segment posterior instrumentation (SSPI) and fusion. OVERVIEW OF LITERATURE: The optimal surgical treatment of thoracolumbar burst fractures remains a matter of debate. SSPI is one of a number of possible choices, yet some studies have revealed high rates of poor radiological outcome for this SSPI. METHODS: Patients treated using the short segment instrumentation and fusion technique at the Spinal Injuries Center (Iizuka, Fukuoka, Japan) from January 1, 2006 to July 31, 2012 were selected for this study. Radiographic parameters such as local sagittal angle, regional sagittal angle, disc angle, anterior or posterior height of the vertebral body at admission, postoperation and final observation were collected for radiological outcome evaluation. RESULTS: There were 31 patients who met the inclusion criteria with a mean follow-up duration of 22.7 months (range, 12-48 months). The mean age of this group was 47.9 years (range, 15-77 years). The mean local sagittal angles at the time of admission, post-operation and final observation were 13.1°, 7.8° and 14.8°, respectively. There were 71% good cases and 29% poor cases based on our criteria for the radiological outcome evaluation. The correction loss has a strong correlation with the load sharing classification score (Spearman rho=0.64, p<0.001). CONCLUSIONS: The loss of kyphotic correction following the surgical treatment of thoracolumbar burst fracture by short segment instrumentation is common and has a close correlation with the degree of comminution of the vertebral body. Patients with high load sharing scores are more susceptible to correction loss and postoperative kyphotic deformity than those with low scores.

Effect of preservation of the C-6 spinous process and its paraspinal muscular attachment on the prevention of postoperative axial neck pain in C3-6 laminoplasty.

OBJECT: Axial neck pain after C3-6 laminoplasty has been reported to be significantly lesser than that after C3-7 laminoplasty because of the preservation of the C-7 spinous process and the attachment of nuchal muscles such as the trapezius and rhomboideus minor, which are connected to the scapula. The C-6 spinous process is the second longest spinous process after that of C-7, and it serves as an attachment point for these muscles. The effect of preserving the C-6 spinous process and its muscular attachment, in addition to preservation of the C-7 spinous process, on the prevention of axial neck pain is not well understood. The purpose of the current study was to clarify whether preservation of the paraspinal muscles of the C-6 spinous process reduces postoperative axial neck pain compared to that after using nonpreservation techniques. METHODS: The authors studied 60 patients who underwent C3-6 double-door laminoplasty for the treatment of cervical spondylotic myelopathy or cervical ossification of the posterior longitudinal ligament; the minimum follow-up period was 1 year. Twenty-five patients underwent a C-6 paraspinal muscle preservation technique, and 35 underwent a C-6 nonpreservation technique. A visual analog scale (VAS) and VAS grading (Grades I-IV) were used to assess axial neck pain 1-3 months after surgery and at the final follow-up examination. Axial neck pain was classified as being 1 of 5 types, and its location was divided into 5 areas. The potential correlation between the C-6/C-7 spinous process length ratio and axial neck pain was examined. RESULTS: The mean VAS scores (± SD) for axial neck pain were comparable between the C6-preservation group and the C6-nonpreservation group in both the early and late postoperative stages (4.1 ± 3.1 vs 4.0 ± 3.2 and 3.8 ± 2.9 vs 3.6 ± 3.0, respectively). The distribution of VAS grades was comparable in the 2 groups in both postoperative stages. Stiffness was the most prevalent complaint in both groups (64.0% and 54.5%, respectively), and the suprascapular region was the most common site in both groups (60.0% and 57.1%, respectively). The types and locations of axial neck pain were also similar between the groups. The C-6/C-7 spinous process length ratios were similar in the groups, and they did not correlate with axial neck pain. The reductions of range of motion and changes in sagittal alignment after surgery were also similar. CONCLUSIONS: The C-6 paraspinal muscle preservation technique was not superior to the C6-nonpreservation technique for preventing postoperative axial neck pain.

Influence of spinal cord compression and traumatic force on the severity of cervical spinal cord injury associated with ossification of the posterior longitudinal ligament.

STUDY DESIGN: Retrospective review. OBJECTIVE: To evaluate the influence of static compression factors and dynamic factors based on the various degrees of traumatic force on the cervical spinal cord injury (SCI) in patients with ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: Spinal cord disorder occurs as a result of various factors, including static factors and traumatic force. Discussions about the severity of paralysis resulting from SCI must therefore focus on dynamic factors based on the traumatic force as well as on static compression factors. However, the past reports did not describe the influence of traumatic force in detail. METHODS: Fifty patients presenting with cervical SCI associated with ossification of the posterior longitudinal ligament were included in this study. The American Spinal Injury Association motor score 3 days after injury, the degree of the traumatic force, and the spinal cord compression rate were investigated, and the relationships among these factors were investigated. RESULTS: Paralysis at the time of injury was not determined by static factors alone or by traumatic force alone. The severity of paralysis at the time of injury was determined on the basis of a combination of both the static factors and the degree of traumatic force. CONCLUSION: Both the degree of spinal cord compression and the degree of traumatic force were found to be important factors associated with the severity of cervical SCI in patients with ossification of the posterior longitudinal ligament. LEVEL OF EVIDENCE: 4.

Clinical relationship between cervical spinal canal stenosis and traumatic cervical spinal cord injury without major fracture or dislocation.

PURPOSE: The purpose of the study was to evaluate the clinical relationship between cervical spinal canal stenosis (CSCS) and incidence of traumatic cervical spinal cord injury (CSCI) without major fracture or dislocation, and to discuss the clinical management of traumatic CSCI. METHODS: Forty-seven patients with traumatic CSCI without major fracture or dislocation (30 out of 47 subjects; 63.83 %, had an injury at the C3-4 segment) and 607 healthy volunteers were measured the sagittal cerebrospinal fluid (CSF) column diameter at five pedicle and five intervertebral disc levels using T2-weighted midsagittal magnetic resonance imaging. We defined the sagittal CSF column diameter of less than 8 mm as CSCS based on the previous paper. We evaluated the relative and absolute risks for the incidence of traumatic CSCI related with CSCS. RESULTS: Using data from the Spinal Injury Network of Fukuoka, Japan, the relative risk for the incidence of traumatic CSCI at the C3-4 segment with CSCS was calculated as 124.5:1. Moreover, the absolute risk for the incidence of traumatic CSCI at the C3-4 segment with CSCS was calculated as 0.00017. CONCLUSIONS: In our results, the relative risk for the incidence of traumatic CSCI with CSCS was 124.5 times higher than that for the incidence without CSCS. However, only 0.017 % of subjects with CSCS may be able to avoid developing traumatic CSCI if they undergo decompression surgery before trauma. Our results suggest that prophylactic surgical management for CSCS might not significantly affect the incidence of traumatic CSCI.

Analysis of the risk factors for tracheostomy in traumatic cervical spinal cord injury.

STUDY DESIGN: A retrospective, consecutive case series. OBJECTIVE: To determine the risk factors that have a statistically significant association with the need of tracheostomy in patients with cervical spinal cord injury (CSCI) at the acute stage. SUMMARY OF BACKGROUND DATA: Respiratory complications remain a major cause of further morbidity and mortality in patients with CSCI. Although several risk factors for tracheostomy have been postulated in these patients, no definitive factors have yet been established according to a multivariate analysis. The use of vital capacity was considered as a single global measure of respiratory function in patients with spinal cord injury, but there are very few studies in which the forced vital capacity was investigated as a risk factor for tracheostomy. METHODS: This study that reviewed the clinical data of 319 patients with CSCI, who were evaluated for their neurological impairment within 2 days after injury, was performed. We analyzed the factors postulated to increase the risk for tracheostomy, including patient's age, neurological impairment scale grade and level, smoking history, pre-existing medical comorbidities, respiratory diseases, Injury Severity Score, forced vital capacity, and percentage of vital capacity to the predicted value (%VC), using a multiple logistic regression model and classification and regression tree analysis. RESULTS: Of 319 patients, 32 patients received tracheostomy (10.03%). The factors identified using a multiple logistic regression model were high age (69 years of age or older), severe neurological impairment scale, low forced vital capacity (≤ 500 mL), and low percentage of vital capacity to the predicted value (<16.3%). The decision tree analysis demonstrated that forced vital capacity, the severe neurological impairment scale, and high patient age were predictive of need for tracheostomy on 94.4% occasions. CONCLUSION: The measurement of forced vital capacity is indispensable to predict the need for tracheostomy in patients with CSCI at the acute stage.

Soft-tissue damage and segmental instability in adult patients with cervical spinal cord injury without major bone injury.

STUDY DESIGN: A retrospective imaging and clinical study. OBJECTIVE: To evaluate the extraneural soft-tissue damage and its clinical relevance in patients with traumatic cervical spinal cord injury (SCI) without major bone injury. SUMMARY OF BACKGROUND DATA: To date, various kinds of cervical discoligamentous injuries have been demonstrated on magnetic resonance images in patients with SCI without bony injury. However, it has not been clear whether these magnetic resonance imaging abnormalities are actually related to spinal segmental instability and the patients' neurological status. METHODS: Eighty-eight adult patients with acute traumatic cervical SCI without major bone injury were examined by flexion-extension lateral radiographs and magnetic resonance images within 2 days after trauma. We excluded patients with flexion recoil injury; therefore, most of the patients included were considered to have sustained a hyperextension injury. Instability of the injured cervical segment was defined when there was more than 3.5-mm posterior translation and/or more than a 11° difference in the intervertebral angle between the site of interest and adjacent segments. The neurological status was evaluated according to the American Spinal Injury Association motor score. RESULTS: On magnetic resonance images, the damage to the anterior longitudinal ligament and intervertebral disc were apparent in 44 and 37 patients, respectively. Various degrees of prevertebral fluid collection (prevertebral hyperintensity) were demonstrated in 76 patients. These magnetic resonance imaging abnormalities were significantly associated with initial cervical segmental instability as judged by flexion-extension radiographs. Interestingly, the American Spinal Injury Association motor score had a significant association with either magnetic resonance imaging abnormalities or segmental instability but not with the cervical canal diameter. CONCLUSION: A considerable proportion of the patients with traumatic cervical SCI without major bone injury were shown to have various types of soft-tissue damage associated with cervical segmental instability at the early stages of the injury. The severity of paralysis greatly depended on these discoligamentous injuries.

Analysis of the risk factors for severity of neurologic status in 216 patients with thoracolumbar and lumbar burst fractures.

STUDY DESIGN: A retrospective, consecutive case series. OBJECTIVE: To determine the risk factors that have a significant correlation with the severity of neurologic impairment in thoracolumbar and lumbar burst fractures. SUMMARY OF BACKGROUND DATA: The correlation between spinal canal stenosis due to bony fragments and the severity of neurologic deficits in thoracolumbar and lumbar burst fractures remains controversial. Moreover, there have so far been no reports in the literature in which the risk factors (spinal canal stenosis and the disruption of posterior ligamentous complex) causing a severe neurologic deficit were analyzed using a multiple logistic regression model. METHODS: A review of the clinical data (neurologic impairments on admission and a finding of posterior ligamentous complex disruption at the time of operation), axial computed tomography, and plain lateral radiography of 216 patients in thoracolumbar (T11-L1) and lumbar (L2-L5) burst fractures was performed. The factors related to neurologic impairments were analyzed using a multiple logistic regression model. RESULTS: In all cases, both the spinal canal stenosis (P < 0.01) and disruption of posterior ligamentous complex (P < 0.01) were significant risk factors. Interestingly, these two risk factors varied according to the injury levels: at thoracic level, the spinal canal stenosis (P < 0.01); at the first lumbar spine, the disruption of the posterior ligamentous complex (P < 0.01); and at the lumbar spine below L2, both of the spinal canal stenosis (P < 0.01) and the disruption of posterior ligamentous complex (P < 0.05) were significant risk factors, respectively. CONCLUSION: In the patients with thoracolumbar and lumbar burst fractures, the significance of the two important risk factors related to clinical results, namely, the stenosis ratio of spinal canal and the disruption of posterior ligamentous complex, were found to vary depending on the level of injury.

A new clinical evaluation for hysterical paralysis.

STUDY DESIGN: A cross-sectional study was performed to elucidate the usefulness of a new clinical evaluation, and a prospective study was performed to detect hysterical paralysis using this evaluation method. OBJECTIVES: To make a correct diagnosis of hysterical paralysis, a new clinical evaluation was developed. SUMMARY OF BACKGROUND DATA: Hysterical paralysis is a conversion disorder. Its diagnosis must be ruled out when encountering a patient with paralysis, therefore imaging and electrophysiological studies are often necessary, but costly. The principal salient diagnostic features for diagnosing hysterical paralysis are thought to be the preservation of a normal reflex pattern, normal rectal sensation, and normal bladder and bowel functions; however, these features are not always successfully identified. METHODS: A new clinical evaluation named the "Spinal Injuries Center" test was developed. The lower extremities of the patients were divided into two groups as follows: in group A, the patients were able to lift up the knee; in group B, the patients were unable to lift up the knee. The 96 legs of the 48 patients who had obvious myelomalacia were randomly chosen. All legs were investigated using the Spinal Injuries Center test, and the association between each group and the Spinal Injuries Center test was examined. The 28 legs of the 14 patients in whom hysterical paralysis was diagnosed were prospectively evaluated using the Spinal Injuries Center test, and the association between the groups and the Spinal Injuries Center test was examined. RESULTS: Forty-eight legs were classified as group A, and 48 legs were classified as group B. In group A, 45 legs were judged to be positive for the Spinal Injuries Center test, and 3 legs were negative. In group B, 1 leg was judged to be positive for the Spinal Injuries Center test, and 47 legs were negative. All legs of the patients with hysterical paralysis were classified as group B; however, all legs were positive for the Spinal Injuries Center test. CONCLUSIONS: The Spinal Injuries Center test is a new clinical evaluation method that can help make a correct diagnosis of hysterical paralysis. When a patient is unable to lift up his knees by himself, the result of the Spinal Injuries Center test is considered to be positive, and hysterical paralysis is diagnosed in such patients. The diagnosis of hysterical paralysis must be ruled out when encountering patients with paralysis, and as a result, imaging and electrophysiological studies are often necessary. Unfortunately, such tests are costly. Thus, a new clinical evaluation for the diagnosis of hysterical paralysis, named the Spinal Injuries Center test, was developed. When patients who are unable to lift up their knees by themselves test positive using the Spinal Injuries Center test, then they are considered to have ether hysterical or simulated paralysis.