Acute spinal cord injury. A study using physical examination and magnetic resonance imaging

Magnetic resonance imaging (MRI) was performed on 37 patients with acute spinal injury using T1- and T2-weighted images. Three different types of MRI signal patterns were detected in association with these spinal cord injuries. A classification was developed using these three patterns. Type I, seen in ten (27.0%) of the patients, demonstrated a decreased signal intensity consistent with acute intraspinal hemorrhage. Type II, seen in 16 (43.2%) of the patients, demonstrated a bright signal intensity consistent with acute cord edema. Type III, seen in three (8.1%) of the patients, demonstrated a mixed signal of hypointensity centrally and hyperintensity peripherally consistent with contusion. The remaining eight patients had normal cords by MRI. All 37 patients had an admitting neurologic assessment and classification of their spinal injury according to the Frankel classification and the Trauma Motor Index (TMI). At an average of 12.1 months postinjury, their neurologic function was reassessed. Patients with Type I patterns showed no improvement in their Frankel classification and minimal improvement in their TMI, 32.1 to 42.4. In comparison, all of the Type II and III patterns improved at least one Frankel classification. The Type II TMI increased from 70.8 to 91.9 and Type III from 37.3 to 75.7. This preliminary report indicates a distinct correlation between the pattern of spinal cord injury as identified by MRI and neurologic recovery. It appears that the ability of MRI to aid in examination of the condition of the spinal cord will offer a means of predicting neurologic recovery following acute spinal cord injury.     

Spinal epidural hematoma associated with streptokinase treatment for myocardial infarction

STUDY DESIGN: Case Report. OBJECTIVE: Thrombolytic therapy has become a routine and valuable care for selected patients with acute myocardial infarction (AMI) and rarely complicates with spinal epidural hemorrhage causing cord compression. SETTING: Elazig, Turkey CASE REPORT: A 72-year-old woman developed spinal epidural hemorrhage following streptokinase and heparin administration for AMI. Back pain and lower extremity neurologic deficits ensued secondary to spinal cord compression by epidural hematoma. Diagnosis of spinal epidural hematoma, extending through T11 to L2 vertebra levels, could be accurately made by magnetic resonance imaging (MRI). Careful follow-up by neurologic examination, reversal of anticoagulant effects, anti-edema treatment with steroids and a low-intensity rehabilitation program maintained a full recovery. Follow-up MRI, 3 months after the accident, revealed complete resolution of the hematoma. CONCLUSION: Physicians should be aware of this rare complication secondary to thrombolytic therapy. A high index of suspicion for hemorrhagic complications is necessary, particularly in elderly patients under thrombolytic treatment regardless of spinal pain, and the patient's lethargic or confused status should be taken into account. MRI is a valuable imaging option that gives information on both localization and extent of lesion and recovery.     

Functional recovery from paraplegia caused by syphilitic meningomyelitis

BACKGROUND: Syphilitic involvement of the nervous system can present in many different ways. We report a patient who presented with rapidly evolving paraparesis secondary to syphilitic meningomyelitis. METHODS: Case report. FINDINGS: Cerebrospinal fluid (CSF) studies confirmed the diagnosis of neurosyphilis. Spinal magnetic resonance imaging (MRI) studies were indicative of leptomeningeal and thoracic spinal cord disease. Treatment with IV penicillin resulted in marked clinical, radiologic, and CSF improvement. MRI imaging provided documentation of spinal cord involvement and was useful in monitoring recovery. This patient's progressive neurologic improvement was monitored for 2 years and documented by periodic Functional Independence Measure scores. CONCLUSION: Recognition of this unusual complication of secondary neurosyphilis is important, because it is a treatable cause of paraparesis with potential for good recovery.     

Magnetic resonance imaging in acute spinal cord trauma

Magnetic resonance imaging (MRI) has proven to be an invaluable tool for evaluating neoplastic, congenital, and degenerative conditions of the spine and spinal cord. Because of various technical limitations, however, the use of MRI in acutely spinal cord-injured patients has not been fully explored. Sixty-two spinal cord-injured patients underwent MRI within the first 36 hours of injury. A variety of pathological findings were detected on the MRI scans: anatomical cord transection (7 cases), spinal cord deformity secondary to extrinsic compression (28), focal cord enlargement/swelling (21), hyperintense intramedullary lesions (17), and disc herniations (2). MRI may be a useful adjunct in the evaluation of acute spinal cord injury.     

Use of magnetic resonance imaging in evaluating injuries to the pediatric thoracolumbar spine

Magnetic resonance imaging (MRI) of acute thoracolumbar spinal injuries allows excellent evaluation of the neurologic and soft tissue structures. Owing to recent advances in imaging techniques that permit greater spatial resolution and more detailed imaging of tissue, MRI now affords effective visualization of injury to the ligaments, intervertebral disk, bones, and spinal cord after spine trauma. Cord changes have been classified into three patterns that are predictive of clinical outcomes in adults with cord injuries. The value of MRI in evaluating pediatric patients with thoracolumbar injuries or in predicting their clinical outcome has not been assessed. After retrospectively reviewing 19 pediatric thoracolumbar fractures associated with neurologic deficits from three level 1 trauma centers, we conclude that MRI is the imaging modality of choice in these patients because it can accurately classify injury to bones and ligaments and because the cord patterns as determined by MRI have predictive value.     

Clinical value of magnetic resonance imaging for cervical myelopathy

The magnetic resonance imaging (MRI) findings in 115 cases of cervical myelopathy, 121 cases of cervical radiculopathy, and 64 cases of neck pain with no neurologic deficit were prospectively studied to investigate the clinical value of MRI for cervical myelopathy. The MRI findings in the T1-weighted sagittal projection were classified into four groups according to the degree of the compressed deformities of the cervical cord. The degree of compression of the cervical cord on MRI findings showed a significant correlation with the severity of myelopathy, the anteroposterior diameter of the spinal column, and the degree of compression of the dural tube in the myelograms (P less than 0.01). Fifty-one patients of cervical myelopathy had undergone both preoperative and postoperative MRI. Of these, the spinal canal of 47 patients that was well decompressed was recognized according to plain computed tomography (CT). However, 24 (51%) of these 47 patients showed on MRI a deformity in the spinal cord amounting to cord atrophy. The correlation between the clinical function of the spinal cord and the recovery of the cord deformity on MRI at the operative levels was accurately investigated in 34 patients who had no cord deformities in the adjacent intervertebral levels. Twenty patients with cord atrophy had slightly poor clinical results, although no significant difference was found between these 20 and 14 patients with recovery in the cord deformities. From these results, it was evident that T1-weighted MRI is useful in the accurate diagnosis of compression myelopathy, in accurately deciding the level of the disease focus, and in the accurate assessment of the surgical results.     

Histopathologic correlation of magnetic resonance imaging signal patterns in a spinal cord injury model

Magnetic resonance imaging (MRI) provides a noninvasive method of monitoring the pathologic response to spinal cord injury. Specific MR signal intensity patterns appear to correlate with degrees of improvement in the neurologic status in spinal cord injury patients. Histologic correlation of two types of MR signal intensity patterns are confirmed in the current study using a rat animal model. Adult male Sprague-Dawley rats underwent spinal cord trauma at the midthoracic level using a weight-dropping technique. After laminectomy, 5- and 10-gm brass weights were dropped from designated heights onto a 0.1-gm impounder placed on the exposed dura. Animals allowed to regain consciousness demonstrated variable recovery of hind limb paraplegia. Magnetic resonance images were obtained from 2 hours to 1 week after injury using a 2-tesla MRI/spectrometer. Sacrifice under anesthesia was performed by perfusive fixation; spinal columns were excised en bloc, embedded, sectioned, and observed with the compound light microscope. Magnetic resonance axial images obtained during the time sequence after injury demonstrate a distinct correlation between MR signal intensity patterns and the histologic appearance of the spinal cord. Magnetic resonance imaging delineates the pathologic processes resulting from acute spinal cord injury and can be used to differentiate the type of injury and prognosis.     

脊髓损伤的MR表现

研究脊髓损伤的MR表现。采用GESigna0．5T超导型磁共振检查机，用脊柱表面线圈，对55例脊柱创伤病人做MR检查。所有病例做轮位和矢状位检查，用自旋回波序列和快速自旋回波序列。脊髓损伤表现为脊髓水肿23例次（41．8％），髓内出血10例次（18．1％），脊髓不完全性和完全性断裂7例次（12．7％），椎间盘值22例次（364％），脊柱韧带断裂30例次（545％）。脊髓损伤多见于爆裂型和骨折脱位型脊柱骨折。MR是脊髓损伤最有效的检查方法，MR对发现和评估脊髓损伤优于CT扫描。     

Immediate spinal cord decompression for cervical spinal cord injury: feasibility and outcome

BACKGROUND: The effect of immediate surgical spinal cord decompression on neurologic outcome after spinal cord injury is controversial. Experimental models strongly suggest a beneficial effect of early decompression but there is little supportive clinical evidence. This study is designed to evaluate the feasibility and outcome of an immediate spinal cord decompression treatment protocol for cervical spinal cord injury in a tertiary treatment center. METHODS: To address this issue, 91 consecutive patients with acute, traumatic cervical spinal cord injury (1990-1997) were prospectively studied. Sixty-six patients (protocol group) underwent emergency magnetic resonance imaging (MRI) to determine the presence of persistent spinal cord compression followed, if indicated, by immediate operative decompression and stabilization. Twenty-five patients were managed outside the treatment protocol because of contraindication to magnetic resonance imaging, need for other emergency surgical procedures, or admitting surgeon preference (reference group). The protocol and reference groups had similar sex and age distributions, admitting Frankel grades, levels of neurologic injury, and Injury Severity Scores. RESULTS: Twenty-seven percent of patients seen were not enrolled in the treatment protocol because of the need for other emergent surgical treatment, contraindication to MRI, and specific surgeon bias regarding the "futility" of emergent treatment. The neurologic outcome for the patients in the reference group were similar to that in the previously reported literature. Fifty percent of protocol patients, compared with only 24% of reference patients, improved from their admitting Frankel grade. Eight protocol patients (12%), but no reference patients, improved from complete motor quadriplegia (Frankel grade A or B) to independent ambulation (Frankel grade D or E). Protocol patients required shorter intensive care unit stays, and shorter total hospital stays than reference patients. In the treatment protocol group, spinal cord decompression, confirmed by MRI, was achieved with immediate spinal column alignment and skeletal traction in 32 patients (46%). Thirty-four patients (54%) required emergent operative spinal cord decompression because of MRI-documented persistent spinal cord compression. CONCLUSION: We conclude that immediate spinal column stabilization and spinal cord decompression, based on magnetic resonance imaging, may significantly improve neurologic outcome. The feasibility of such a treatment protocol in a tertiary treatment center is well demonstrated. Additional multicenter trials are necessary to achieve definitive conclusions regarding clinical efficacy.     

Magnetic resonance imaging of acute cervical spine trauma. Correlation with severity of neurologic injury

Prior to the advent of computer-assisted imaging techniques, conventional radiographic studies did not accurately depict the severity of soft tissue injury (spinal cord and paravertebral tissue) attending severe spinal trauma. Computed tomography scanning is clearly superior to plain radiography in the demonstration of osseous fractures and impactions, but this modality does not clearly depict ligamentous or disc injuries and does not image the spinal cord directly. The authors' preliminary experience indicates that magnetic resonance imaging (MRI) more accurately defines the extent of soft tissue damage in the zone of injury. In this study, the authors correlate these objective imaging techniques with findings on neurologic exam. Seventy-eight patients with cervical spine injuries admitted to the Regional Spinal Cord Injury Center of the Delaware Valley between August 1987 and January 1989 were evaluated with surface-coil MRI on a 1.5-Tesla unit. Fifty-nine patients were studied within 7 days of injury. Image sequences consisting of T1-, proton density, and T2-weighted images were obtained in saggital views. Axial gradient recalled acquisitions in the steady state (GRASS) images were obtained from most patients. We learned that certain patterns of MRI signal were associated with severe neurologic deficit. These include: 1) intramedullary hematoma and 2) spinal cord contusion associated with edema encompassing more than one spinal segment. Magnetic resonance imaging findings also correlated with less severe injury and include 1) normal spinal cord signal and 2) small focal contusions associated with edema encompassing one spinal segment or less.     

APS Recommendations for Skin Care of Hospitalized Patients with Acute Spinal Cord Injury

Abstract

Background: Syphilitic involvement of the nervous system can present in many different ways. We report a patient who presented with rapidly evolving paraparesis secondary to syphilitic menmgomyelitis.

Methods: Case report.

Findings: Cerebrospinal fluid (CSF) studies confirmed the diagnosis of neurosyphilis. Spinal magnetic resonance imaging (MRI) studies were indicative of leptomenmgeal and thoracic spinal cord disease. Treatment with IV penicillin resulted in marked clinical, radiologic, and CSF improvement. MRI imaging provided documentation of spinal cord involvement and was useful in monitoring recovery. This patient's progressive neurologic improvement was monitored for 2 years and documented by periodic Functional Independence Measure scores.

Conclusion: Recognition of this unusual complication of secondary neurosyphilis is important, because it is a treatable cause of paraparesis with potential for good recovery.     

Carotid and vertebral artery injury in survivors of atlanto-occipital dislocation: case reports and literature review

Atlanto-occipital dislocation (AOD) usually results in immediate death from transection of the upper cervical spinal cord near the spinomedullary junction. However, over the last several decades increasing numbers of AOD survivors have been identified. Although many of these patients initially demonstrate profound neurologic deficits, a number who survive have regained most or all neurologic functions, indicating that they did not suffer mechanical disruption of the spinal cord at the time of AOD. In the survivors, a growing body of evidence indicates that many of the initial neurologic deficits are related to vascular injury to the carotid or vertebral arteries and their branches. We recently encountered three AOD survivors with no evidence of mechanical injury to the spinal cord in which angiography demonstrated vascular injury to the internal carotid artery in the form of vasospasm in one case and to the vertebral arteries in the forms of focal stenosis at the site of dural penetration, focal stenosis and distal vasospasm, and focal stenosis with distal intimal flap and dissection in one case each. Autopsy after one of the three died after cardiac arrest demonstrated diffuse infarction of the cerebrum, cerebellum, midbrain, brainstem, and upper cervical spinal cord without evidence of mechanical laceration or transection of the spinal cord. Recovery of neurologic function in two cases following prompt immobilization and angiography suggests that neurologic deficits secondary to vascular injury are potentially reversible.     

Occult spinal dysraphism in patients with anal agenesis

Recent reports have suggested an association between congenital anorectal anomalies and occult spinal dysraphism. Eighty-seven patients with anal agenesis have been treated at this institution over the last 14 years. Two of these patients had spinal cord anomalies recognized at birth (a myelomeningocele and a tethered spinal cord). Two additional patients presented with progressive neurologic deficits in early childhood and were each found to have a tethered spinal cord. To further assess the magnitude of this problem, we have used magnetic resonance imaging (MRI) of the spine to survey prospectively 23 infants with anal agenesis. Twenty-one former patients who were asymptomatic were recalled and also studied. Four of 44 patients (9%) were found to have significant occult spinal dysraphism; each child had undergone neurosurgical operation without morbidity. MRI found each child to have a tethered spinal cord, either as an isolated lesion (2) or in association with a syrinx (1) or lipomyelomeningocele (1). One of these patients had a neurologic deficit detected on careful preoperative evaluation. The other three, two of whom were less than 2 years old, had no detectable deficit. Neither the extent of the anorectal malformation, the absence of associated congenital anomalies, nor the demonstration of normal vertebral anatomy on plain radiographs of the spine precluded the presence of occult spinal dysraphism. Therefore, we recommend that all patients with anorectal anomalies undergo MRI imaging of their spines during initial evaluation to screen for occult spinal dysraphism. In addition, consideration should be given to recalling older patients for MRI evaluation.     

Functional recovery and regeneration of descending tracts in rats after spinal cord transection in infancy

STUDY DESIGN: The functional recovery of rats that underwent spinal cord transection in infancy was evaluated by multimodal examination (functional tests, electrophysiologic evaluation, tract-tracing) to determine the basis for the recovery. OBJECTIVES: To determine whether the hind limb function in rats that underwent spinal cord transection in infancy is regained completely, which descending tracts regenerate after the transection, and whether the functional recovery is correlated with axonal reconnection. SUMMARY OF BACKGROUND DATA: It is widely accepted that a newborn rat recovers its hind limb function after spinal cord transection even without any specific treatments. This functional recovery might be attributed to possible regeneration of some descending pathways, although there is a counterargument that well-trained spinal cord reflexes may bring about functional compensation. METHODS: The thoracic spinal cord of infant rats was completely transected at Th10 when they were 2 weeks of age. Multimodal functional tests and electrophysiologic studies were performed 5 weeks later. Some recovered rats (i.e., those able to walk after the transection) underwent spinal cord retransection, with subsequent reevaluation of locomotion and muscle-evoked potentials. At 6 weeks after the initial transection, tract-tracing studies were performed in some animals. RESULTS: A motor performance score detected the functional differences between the control and the recovered rats. Muscle-evoked potentials of hind limbs after electrical stimulation to the brain were recorded in some of the recovered rats, but never in the unrecovered rats. Moreover, the muscle-evoked potentials of the recovered rats disappeared after spinal cord retransection that resulted in loss of voluntary movement. Morphologic studies in two rats provided evidence that reconnection of rubrospinal, vestibulospinal, and reticulospinal tracts had occurred, whereas corticospinal regeneration was not detected. CONCLUSIONS: It can be concluded that the hind limb function of rats that underwent spinal cord transection in infancy was partially regained; that axonal regeneration of the rubrospinal, vestibulospinal, or reticulospinal tracts was demonstrated, whereas the reconnection of the corticospinal tract was not observed; and that the axonal regeneration of these tracts is involved in the functional recovery.     

Is extensive cervical laminoplasty an effective treatment for spinal cord sarcoidosis combined with cervical spondylosis?

Patients with neurosarcoidosis are usually initially treated with steroid administration even when they have concomitant cord compression on magnetic resonance imaging (MRI). Operative intervention may be indicated in patients with spinal cord sarcoidosis requiring either tissue biopsy for diagnosis or associated with progressive neurologic symptoms. However, there have been no previous reports describing clinical outcomes of laminoplasty for spinal cord sarcoidosis. The objectives of this study are to investigate whether extensive cervical laminoplasty is an effective treatment for spinal cord sarcoidosis combined with spondylotic changes and/or cervical spinal canal stenosis. Open-door laminoplasty was performed in three patients with spinal cord sarcoidosis. All patients received intensive corticosteroid therapy after the operation MRI imaging was performed in all patients before and after the operation. Operative outcomes were not satisfactory and the clinical courses of the patients fluctuated after corticosteroid therapy. Daily life activities were not significantly improved after treatments in any of the three patients, and in the long-term follow-up period the clinical course of one patient was one of inexorable deterioration to a state of quadriplegia. The possibility of spinal cord sarcoidosis should be included in the differential diagnosis, when a distinct high signal intensity area is observed within the spinal cord on T2-weighted MR images in patients with spondylotic changes. Laminoplasty is not an effective intervention for the treatment of spinal cord sarcoidosis even when patients have spondylotic changes and/or a constitutionally narrowing cervical spinal canal. Patients with neurosarcoidosis should be treated first with steroid administration even when they have concomitant cord compression on MRI.     

The role of magnetic resonance imaging in acute cervical spine fractures

Background contextThe role of magnetic resonance imaging (MRI) in neurologically intact cervical spine fractures is not well defined. To our knowledge, there are no studies that clearly identify the indications for MRI in this particular scenario. Controversy remains regarding the use of MRI in at-risk patients, primarily the obtunded and elderly patients.PurposeThe purpose of the present study was to examine the predisposing conditions where an MRI would provide additional findings that would affect management in acute cervical spine fractures.Study designRetrospective cohort involving radiographic and clinical review.Patient sampleConsecutive patients with acute cervical injuries at a single institution.Outcome measuresNeurologic recovery.MethodsA review of 830 patients with cervical spinal injuries between 2006 and 2010 was performed. Clinical information was obtained for all the patients: Glasgow Coma Scale, mechanism of injury, major medical comorbidities, associated injuries, neurologic examination, neurologic symptoms, sex, age, and alertness. Two experienced fellowship-trained spine surgeons determined if the MRI study changed the management in the individual cases based on the Sub-axial Cervical Spine Injury classification system.ResultsNinety-nine patients with a cervical fracture were included in the final analysis: median age 54 years (interquartile range, 42 years), mean Glasgow Coma Scale 13 (standard deviation±3.0), 68% males, 32% females, 42% older patients (age>60 years), 30% spondylosis, 27% polytrauma, 67% alert, 28% neurologic deficit. Major medical comorbidities, prior to injury level of activity, atlantoaxial versus subaxial, and gender were not associated with changes in diagnosis and management (p>.05). Age >60 years, neurologic deficit, polytrauma status, alertness, and spondylosis were associated with having additional clinically relevant findings seen on MRI and changes in management (p<.05). The majority of the changes in management were related to MRI's illustration of the spinal cord injury and not due to an occult instability. Eighty-one percent of the changes in management were related to the depiction of the spinal cord compression seen on MRI, whereas 19% of the changes in management were related to occult instability seen on MRI.ConclusionsOlder age (>60 years), obtunded or temporary non-assessable status, cervical spondylosis, polytrauma, and neurologic deficit are predisposing factors for further injury found on MRI but missed on computed tomographic scan alone. These additional findings can affect the management in acute cervical spine fractures. The rational of the on-call spine surgeon to order an MRI for a cervical spine fracture is well founded and often that MRI will affect the fracture management. Magnetic resonance imaging particularly helps with better defining the type of spinal cord compression. Picking up occult instability missed on computed tomographic scan was possible with MRI but not as common.     

急性无骨折脱位型颈髓损伤的机制与治疗

目的 探讨急性创伤性无骨折脱位型颈脊髓损伤的机制及治疗方法。方针 对２７例无骨折脱位型颈脊髓损伤患者进行ＲＭＩ检查;８例颈椎间盘突出对脊髓压迫明显者予以手术治疗,１９例予以非手术治疗;分别于入院时及治疗后６周对脊髓损伤程度按ＡＳＩＡ标准分级评定。结果 采用大剂量甲基强的松龙治疗６例患者,６周后ＡＳＩＡ分级平均提高了２个等级,神经功能改善较明显;颈椎间盘突出明显者早期手术治疗神经功能有一定改善,受伤     

Advanced imaging of the cervical spine and spinal cord in 22q11.2 deletion syndrome: age-matched, double-cohort, controlled study

Purpose  The 22q11.2 deletion syndrome is a common genetic syndrome with a wide spectrum of abnormalities. We have previously described multiple anomalies of the upper cervical spine in this disorder. The objective of this study was to use advanced imaging to further define the morphology of the cervical spine and spinal cord in the 22q11.2 deletion syndrome, with a comparison to age-matched controls. Methods  A total of 32 patients with a 22q11.2 deletion underwent advanced imaging (computed tomography/magnetic resonance imaging; CT/MRI) of the cervical spine. In 27 patients, space available for the cord (SAC); the sagittal diameter of the vertebral body, spinal canal, cerebrospinal fluid (CSF), and spinal cord; and the cross sectional area of the spinal canal, CSF, and spinal cord were measured at each cervical level and compared to 29 age-matched controls. Statistical analysis was performed and potential implications were hypothesized. Results  In 22q11.2 patients, advanced imaging identified 40 pathologies not evident on plain radiographs with potential mechanical and/or neurological implications. These patients also had significantly smaller values (P ≤ 0.05) of the following parameters at one or more cervical levels, relative to age-matched controls: width of the vertebral body, spinal canal, CSF, and spinal cord; area of the spinal canal, CSF, and spinal cord. Neurologic symptoms were observed in 4/32 patients, with one patient requiring surgical intervention. Conclusions  Advanced imaging of the cervical spine can detect findings not evident on plain radiographs in the 22q11.2 deletion syndrome. CT and/or MRI may be indicated when there is a high index of suspicion for clinical instability or neurologic compromise in order to rule out dynamic encroachment or impending neurologic sequelae. Spinal canal and spinal cord dimensions are reduced in these patients relative to controls with currently unknown clinical significance.     

Restoration of motor function after operative reconstruction of the acutely transected spinal cord in the canine model

Background

Cephalosomatic anastomosis or what has been called a “head transplantation” requires full reconnection of the respective transected ends of the spinal cords. The GEMINI spinal cord fusion protocol has been developed for this reason. Here, we report the first randomized, controlled study of the GEMINI protocol in large animals.

Preoperative radiological and electrophysiological evaluation in 100 adolescent idiopathic scoliosis patients

This is a prospective study of spinal magnetic resonance imaging (MRI), electrophysiological recordings, and neurological examinations of 100 patients admitted for surgery for adolescent idiopathic scoliosis (AIS), which was conducted to assess the prevalence of structural and functional abnormalities within the spinal cord in patients with clinically normal neurologic condition. In all patients the clinical diagnosis and intact neurological condition was ascertained by a spinal orthopedic surgeon. Full-length spinal axis MRI studies (T1/T2 sequences) and somato-sensory evoked potentials of the tibial nerves (tSSEPs) were preoperatively assessed by independent evaluators blinded to the patients' medical histories. Structural spinal cord abnormalities were found in three of 100 AIS patients on MR imaging. In one patient a Chiari malformation type 1 with an accompanying syringomyelia was diagnosed, which required a suboccipital decompression. In the other two patients small thoracic syringomyelias were diagnosed. Abnormalities of spinal cord function were detected in 68% of the 100 patients: tSSEP latencies corrected for body height were increased in 56% of the patients; pathological differences between tSSEPs on the left and right sides were present in 17% (12% in combination with a prolongation of the latency). The findings of this study indicate that MRI and electrophysiological examinations are essential to assess spinal cord abnormalities that are clinically not detectable in AIS patients. Even in patients with intact neurologic condition and clinically typical right-curved thoracic scoliosis, the possibility of intraspinal pathologies should be ruled out by MRI. It is especially important to detect structural pathologies like syringomyelia and Chiari malformation before proceeding with scoliosis surgery, as these conditions are associated with a higher neurological risk during scoliosis surgery. The electrophysiological recordings made in the present study, with the high number of pathological tSSEPs, are indicative of functional abnormalities with a subclinical involvement of the recorded neuronal pathways. The relevance of the latter findings is not yet clear, but pre-operative tSSEP examinations offer the possibility of assessing alterations in spinal cord function that are undetectable by clinical examination.