Classification of spinal injuries based on the essential traumatic spinal mechanisms

STUDY DESIGN: A biomechanical unitary classification of spinal injuries is proposed. OBJECTIVE: To present an evaluation of spinal injuries based on the essential traumatic spinal mechanisms: axial deformation, torsion, translation and combined mechanisms in connection with the concept of the stabilizing axial spinal pillar. SETTING: Hospital 'Sf. Treime', Iasi, Romania. METHODS: The essential mechanisms of spinal injuries are considered: (1) axial deformation with (a) compression (centric or eccentric), most often eccentric, including compression in flexion or extension; (b) spinal elongation with distraction as centric elongation, but frequently axial eccentric elongation and a flexion or extension injury; (2) torsion or axial spinal rotation, (3) segmental translation, with a shearing version for the double translation and (4) combined mechanisms - the most frequent situation. Over 300 patients with spinal injuries were analysed and the spinal instability was determined using the criteria of clinical instability. The cases of spinal instability were studied in connection with the types of lesion of the central axial spinal pillar. RESULTS: All cases with lesions of the central axial spinal pillar had traumatic spinal instability. The spinal instability was absent in cases of isolated lesions of the anterior or posterior secondary pillar. The X-ray and spinal CT analysis of the traumatic spinal lesions showed the types of lesions and specified the mechanisms of spinal injuries. The combined mechanisms were responsible for the majority of the spinal injuries. CONCLUSIONS: Spinal instability occurs because of the lesion of the central axial spinal pillar The types of lesions of the central spinal pillar and of the secondary spinal pillars are determined by the essential traumatic spinal mechanisms: axial deformation (with compression or elongation), axial rotation, translation and most frequently the above combined mechanisms.     

Radiological Investigations and Intra-operative Evoked Potentials for the Diagnosis of Nerve Root Avulsion: Evaluation of Both Modalities by Intradural Root Inspection

Summary  Fourteen patients with traumatic brachial plexus injuries underwent intradural inspection of cervical nerve roots to evaluate radiological and intra-operative electrophysiological findings concerning cervical nerve root avulsion from the spinal cord. Four neurosurgeons of our department assessed independently from each other both myelography and CT-myelography concerning intradural nerve root lesions. Each neurosurgeon assessed a total of 26 cervical nerve roots. Two investigators assessed 6/26 and 2 investigators 7/26 nerve roots falsely concerning ventral or/and dorsal root lesions compared with the findings on intradural inspection (23% and 27% false findings). There was a considerable variance concerning the assessibility and findings among the 4 neurosurgeons. Reconstructive surgery was performed after a mean interval of 6.5 months following trauma and 2 weeks following intradural inspection. After exposure of the brachial plexus and the cervical nerve roots in question via a ventral approach, 13 cervical nerve roots were stimulated electrically close to the neuroforamen and cortical evoked potentials (root-SEPs) were recorded from the contralateral postcentral region. All 5 roots with SEPs were intact (no root lesion) and all 8 roots without SEPs showed interrupted (ventral or/and dorsal) rootlets on intradural inspection. Our results demonstrate that false radiological findings concerning root lesions are possible. Intra-operative root-SEPs seem to be a useful aid for evaluation of cervical nerve root lesions. However, more electrophysiological data are necessary to ascertain, if this modality is able to replace intradural inspection in unclear radiological cases in the future.     

Spinal cord compression from traumatic anterior cervical pseudomeningoceles. Report of three cases

Pseudomeningoceles rarely develop after cervical trauma; in all reported cases the lesions have extended outside the spinal canal. The authors report the first known cases of anterior cervical pseudomeningoceles contained entirely within the spinal canal and causing cord compression and neurological injury. The authors retrospectively reviewed the cases of three patients with traumatic cervical spine injuries and concomitant compressive anterior pseudomeningoceles. The lesion was recognized in the first case when the patient's neurological status declined after he sustained a severe atlantoaxial injury; the pseudomeningocele was identified intraoperatively and decompressed. After the decompressive surgery, the patient's severe tetraparesis partially resolved. In the other two patients diagnoses of similar pseudomeningoceles were established by magnetic resonance imaging. Both patients were treated conservatively, and their mild to moderate hemiparesis due to the pseudomeningocele-induced compression abated. The high incidence of anterior cervical pseudomeningoceles seen at the authors' institution within a relatively brief period suggests that this lesion is not rare. The authors believe that it is important to recognize the compressive nature of these lesions and their potential to cause devastating neurological injury.     

High Cervical Disc Lesions in Elderly Patients – Presentation and Surgical Approach

Summary  The incidence of high cervical disc lesions is extremely rare, and the mechanism of their development is unclear. We report these three cases, and discuss the possible mechanisms. We also describe surgical strategies for these lesions.  The first and second cases were an 82-year-old male and an 84-year-old male with retro-odontoid disc hernia. The third was an 83-year-old female with a herniated disc at C2/C3. To investigate Aetiological mechanisms of these lesions, we examined the findings on cervical images in extension and flexion, and compared the results in a younger than 80-year-old group and an older than 80-year-old group.  The patients underwent surgery via a posterolateral intradural approach. Wide laminectomy and incision of the dentate ligaments enabled access to the ventral space of the upper cervical spinal canal and sufficient decompression. All patients became ambulatory postoperatively without special fixation of the cervical spine. In the younger group, the level mostly loaded during cervical movement was C5/6, however, the levels in the older group were C2/3 and C3/4.  In elderly patients, less mobilization of the middle and/or lower cervical spine due to spondylotic change causes overloading at higher levels resulting in high cervical disc lesions. Retro-odontoid disc lesions can be caused by a herniated disc at C2/C3, which migrates upward. Regarding surgical strategy, the posterolateral intradural approach is less invasive and more advantageous for these lesions.     

Coagulopathy Induced Spinal Intradural Extramedullary Haematoma: Report of Three Cases and Review of the Literature

Summary  In a retrospective review of 3 patients operated for coagulopathy induced spinal intradural-extramedullary haematoma the literature regarding coagulopathy induced spinal haemorrhage is reviewed and the etiology of these rare spinal subdural and subarachnoid haemorrhages is discussed.  Spinal intradural haematomas are usually related to trauma or a previous lumbar puncture. A review of the literature revealed only a handful cases of spinal intradural haemorrhages occurring secondary to an underlying haematological disorder or an iatrogenic coagulopathy.  Coagulopathy induced spinal haemorrhage should be included in the differential diagnosis of acute paraparesis in patients with co-existent haematological disorders or undergoing anticoagulation therapy. Due to the often mixed subdural and subarachnoid bleeding patterns we have termed this entity spinal intradural-extramedullary haematoma.     

Traumatic injuries to the craniovertebral junction: a review of rare events

The craniovertebral junction is a specific region of the spine with unique anatomical and biomechanical properties that yields a wide variety of injury patterns. Junctional traumatic fractures and/or dislocations are widely reported in clinical practice, but we could identify only a subgroup of upper cervical spine traumatic injuries with very few cases reported in the literature, and for this reason may be considered rare. In some of these cases, the absence of spinal biomechanical instability, in association with moderate clinical symptoms (neck stiffness and pain) and the difficulty in fracture identification through standard cervical radiographs, leads to a high percentage of missed injuries. In other cases, traumatic events have been commonly described only in autopsy series due to the high degree of spinal biomechanical instability. Herein, we have summarized all the relevant literature concerning this issue and also included our cases, with the aim of emphasizing prompt diagnosis and correct management. We provide a guide for correctly identifying “rare” craniovertebral junction traumatic injuries.     

Noncontiguous Spinal Metastases and Plasmocytomas Should be Operated on Through a Single Posterior Midline Approach, and Circumferential Decompression Should be Performed with Individualized Reconstruction

Summary  Background. In noncontiguous spinal metastatic disease, anterior or combined anterior-posterior surgery is an effective treatment. The objective of this study is to investigate whether circumferential decompression through a single-stage posterior midline approach with individualized spinal reconstruction can still achieve comparable results for functional improvement and for maintenance of spinal alignment in the absence of the risks associated with the more invasive transcavitary or combined approaches.  Method. Seventeen patients with noncontiguous spinal metastases and plasmocytomas at one or two adjacent levels were included in this series. Circumferential decompression was obtained with anterior reconstruction and posterior fixation in ten patients, and with posterior instrumentation alone in seven patients. Postoperatively the patients were prospectively followed, and their functional status and spinal alignment were periodically evaluated.  Findings. Fourteen patients died from progression of their underlying cancer. Their mean survival time was 8 months (range: 1 to 21 months). Three survivors were evaluated at 10, 4 and 3 months respectively. At one month after surgery, 14 patients (82%) showed neurological improvement. Of 10 preoperative nonambulators, seven regained walking capacity. Five patients who were ambulatory with assistance improved to full functional independence. Local tumour recurrence was recorded in one patient after subtotal vertebrectomy for a plasmocytoma at L5. No other tumour recurrences were noted. In one patient a partial loss of correction occurred at T6 – without functional deterioration, however. Spinal alignment was maintained in all other patients who became or remained ambulatory. No major intra-operative complications or peri-operative deaths occurred. CSF leakage was recorded as the most common complication in four patients.  Interpretation. Circumferential decompression and spinal reconstruction through a single-stage posterior midline approach is feasible and effective. The extent of surgery can be individualized by means of this technique to the patient's specific problem. In patients with limited life expectancy from metastatic neoplastic disease, the results compare favourably with the more invasive anterior or combined antero-posterior procedures.     

Case Reports of Symptomatic Metastases in Four Patients with Primary Intracranial Gliomas

Summary  Four patients with primary intracranial high-grade gliomas are reported. Three of them developed spinal symptoms and signs generated by spinal metastases a few months after first diagnosis, the last patient developed an extraspinal metastasis in cervical lymph nodes. The spinal metastasis of a 30 years old patient was located intradurally at L5/S1, in the second patient at level L3, the third patient presented with multiple metastases in the cervical, thoracic and lumbar spine.  Previously reported cases are reviewed, are discussed in the light of our own observations and analysed for the various therapeutic options.     

Airway complications in traumatic lower cervical spinal cord injury: A retrospective study

Objective

To investigate risk factors for pneumonia in patients with traumatic lower cervical spinal cord injury.

Design

Observational study, retrospective study.

Setting

Spinal cord unit in a maximum care hospital.

Methods

Thirty-seven patients with acute isolated traumatic spinal cord injury at levels C4–C8 and complete motor function injury (AIS A, B) treated from 2004 to 2010 met the criteria for inclusion in our retrospective analysis. The following parameters were considered: ventilation-specific parameters, re-intubation, creation of a tracheostomy, pneumonia, antibiotic treatment, and length of intensive care unit (ICU) stay and total hospitalization.

Results

Among the patients, 81% had primary invasive ventilation. In 78% of cases a tracheostomy was created; 3% of these cases were discharged with invasive ventilation and 28% with a tracheostomy without ventilation. Pneumonia according to Centers for Disease Control criteria occurred in 51% of cases within 21 ± 32 days of injury, and in 3% at a later date. The number of pre-existing conditions was significantly associated with pneumonia. Length of ICU stay was 25 ± 34 days, and average total hospital duration was 230 ± 144 days. Significant factors affecting the duration of ventilation were the number of pre-existing conditions and tetraplegia-specific complications.

Conclusions

Our results confirm that patients with traumatic lower cervical spinal cord injuries defined by lesion level and AIS constitute a homogeneous group. This group is characterized by a high rate of pneumonia during the first 4 weeks after injury. The number of pre-existing general conditions and spinal injury-specific comorbidities are the only risk factors identified for the development of pneumonia and/or duration of ventilation.     

Spinal clearance in the difficult trauma patient: a role for screening MRI of the spine

Identifying spinal injuries in trauma patients with altered mental status can be difficult. CT scanning and clinical examination are the basis of our spinal clearance, but screening "trauma protocol" spinal MRI is used to exclude occult injuries. We sought to evaluate the sensitivity of CT scanning for spinal injuries compared with our MRI protocol. Ninety-seven patients underwent MRI cervical spine trauma protocol during 2004. Twenty-nine patients were obtunded, 29 had neurologic symptoms, and 39 had spine pain. MRI confirmed the initial CT findings without new injuries in 83 cases. MRI reclassified fractures as degenerative changes in 12 cases. In 2 cases, the MRI identified new injuries: one a stable partial ligament tear, the second a T7 Chance fracture with ligamental disruption requiring operative fixation. There was no morbidity or mortality documented in obtaining the MRI studies. Overall negative predictive value of CT scanning of the spine was 98 per cent, the positive predictive value was 78 per cent, and the sensitivity and specificity was 94 per cent and 91 per cent, respectively. CT scanning of the cervical and axial spine is sensitive for spinal trauma but not specific. MRI trauma protocol should be reserved for cases when initial CT scanning is suggestive of traumatic injury.     

无骨折、脱位的颈脊髓损伤

通过对176例外伤性颈脊髓损伤中24例无骨折、脱位病例的回顾分析,认为MRI对不伴骨折或脱位的颈髓损伤的诊断是目前较可靠手段。提出这些病例可分为脊髓压迫型和无脊髓压迫型。治疗上前者以前路减压为佳,而脊髓内外联合减压术对阻止后者神经损害的进展有帮助。早期诊断,尽早制动,牵引乃至手术十分必要。     

A Review of the Neuropathology of Human Spinal Cord Injury with Emphasis on Special Features

Abstract

A judicious understanding of the basic neuropathology of spinal cord injuries (SCI) is essential knowledge for the clinician responsible for SCI management. An appreciation of the nature of human SCI is also necessary for the neuroscientist searching for a cure. The neuropathology of human SCI described here is derived from the study of 564 cases of spinal cord trauma held in a tissue bank and database of the Department of Neuropathology, Royal Perth Hospital in Australia. The main features of SCI neuropathology are reviewed and special aspects such as early axonal lesions, traumatic demyelination-remyelination, and quantification of white matter tracts are reported in more detail. One of the remarkable outcomes of this work is the finding that the majority of SCI patients have a proportion of spinal corcJ white matter maintained across the level of the lesion, an observation that has important therapeutic implications. (J Spinal Cord Med 1999;22:119–124)     

Idiopathic Spinal Cord Herniation: Case Report and Literature Review

Summary  We report one case of spontaneous thoracic spinal cord herniation presenting with a progressive spastic paraparesis for 4 years in a 55 years old man. From preoperative MRI, showing a ventrally displaced atrophic spinal cord at T2–T3 level, a dorsal intradural arachnoid cyst was suspected. At operation, after a 3 level laminectomy, no arachnoid cyst was found and spinal cord herniation into a meningeal diverticulum was confirmed. The herniated myelon was replaced intradurally and the lumen of the diverticulum was filled with Teflon? settled with fibrin glue to prevent recurrence. Postoperatively some neurological recovery was achieved.  The literature was reviewed, regarding clinical and epidemiological features, proposed pathophysiological mechanisms, treatment options and outcome. Only 32 surgically proved cases of thoracic spinal cord herniation with no past history of spine trauma, injury or surgery were found.     

Posttraumatic arachnoidal diverticula

Summary Arachnoidal diverticula of the spinal cord and nerve roots are relatively common lesions. Many of these lesions are congenital, but some may occur as a result of trauma or spinal surgery. This report reviews the Mayo Clinic experience with postsurgical and traumatic lesions. Of the 17 patients in the series, 11 had previous operation in the region of the lesion and 6 had nonsurgical trauma.     

Vertebral epidural arteriovenous fistula and radicular pain in neurofibromatosis type I

Summary.  A minor trauma caused opening of an arteriovenous fistula between the right vertebral artery and cervical spinal epidural venous plexus in a patient with neurofibromatosis Type I. Subsequent dilation of the plexus caused compression of the spinal cord and radicular symptomology of the right upper extremity. The single-hole fistula and its arterial feeder were filled with electrodetachable coils via an intra-arterial approach. This lead into shrinkage of the plexus, reformation of the cord caliber and full and stable clinical recovery. The achieved endovascular occlusion of the fistula proved to be permanent on follow-up.     

Migration of Pacemaker Lead Into the Spinal Venous Plexus: Case Report with Special Reference to Batson's Theory of Spinal Metastasis

Summary  Objective and Importance. Migration of a foreign material via venous routes into the spinal canal is a very rare incidence. We report the second case in which a foreign body has migrated into the spinal canal via the venous route.  Clinical Presentation. This 35-years-old man presented with sudden onset of severe low back pain and pain in the right leg four months after an unsuccessful attempt to remove a disconnected cardiac pacemaker lead via the femoral vein. Direct lumbar x-ray demonstrated the broken lead of the cardiac pacemaker at the entrance of the right L5 foramen which was also demonstrated by lumbar CT.  Surgical Intervention. After right L5 hemilaminotomy, the pacemaker lead was found in a vein of the anterior spinal venous plexus just beneath and lateral to the right L5 root. After dissecting it from the surrounding adipose tissue, the embolised pacemaker lead was taken out.  Conclusion. We present a case report and review of the literature on migration of foreign material into the spinal canal, factors effecting the flow directions in the spinal veins. This case may be the first evidence that proved Batson's theory of spinal metastases in man.     

Blunt craniocervical artery injury in cervical spine lesions: the value of CT angiography

Objective  

The awareness of traumatic craniocervical artery injuries has increased over the last years, and the detection rate varies in published trauma series. These injuries are often associated with cervical spinal and cranial trauma. The purpose of this prospective study was to determine the frequency and injury characteristics of blunt traumatic cervical artery injuries in patients suffering from cervical spine injuries by using a standardized CT angiography (CTA) protocol of the craniocervical vessels.     

An analysis of the results of transferring the musculocutaneous nerve onto the median nerve in tetraplegics

Summary Following injuries of the cervical spinal cord at the common level with C6 neurological level sparing, abduction of the shoulder and elbow flexion remain active. The flexors of the elbow are controlled by the musculocutaneous nerve formed mainly from C5 and C6 fibers, the motor cells of which are usually located above the level of the spinal lesion. The encouraging report of anastomosis of the musculocutaneous nerve to the median nerve, described by Benassy and Robart, induced us to perform similar operations in 42 patients with traumatic tetraplegia. In 32 patients this has restored simple grasping function of the hand, increasing the patients' independence. The operation is particularly indicated in cases of complete lesion of the spinal cord at the C6–C7 level in young people, and for best results. should be performed with in the first few months after trauma.     

无骨折脱位颈脊髓损伤的实质探讨

目的 探讨无骨折脱位型颈脊髓损伤的实质。方法 54例无骨折脱位颈脊髓损伤,分析其MRI表现。采取摘除突出椎间盘或/和清除椎管后方致压物、扩大椎管的手术治疗,随访其术后疗效。结果 MRI显示外伤性颈椎间盘突出为主,同一节段黄韧带、棘间和棘上韧带等软组织损伤,导致脊髓压迫、挤压性损害。术后54例病人都有不同程度的康复。结论 外伤引起的颈椎间盘突出挤压脊髓和一过性损伤是无骨折脱位颈脊髓损伤的主要原因。     

Extramedullary Hemangioblastoma of the Conus Medullaris

Summary ? Background. We report the case of an extramedullary pathologically proven hemangioblastoma of the conus medullaris. As spinal dural arteriovenous fistulas most commonly present with a conus medullaris syndrome, our presentation of the MRI, myelographic, and angiographic findings of this unique lesion may be useful in differentiating these two entities.  Clinical Material. We report the case of a 57 year old woman with a two year history of progressive low back and right lower extremity pain and weakness. Spinal MRI and myelography demonstrated serpiginous vasculature on the dorsum of the spinal cord consistent with either a vascular tumor or malformation. Selective spinal angiography was thus undertaken by the neuroendovascular team which revealed a tumor nodule consistent with vascular tumor. T12-L1 laminectomy was performed and a 6 mm vascularized tumor was found in the intradural extramedullary compartment adjacent to the conus medullaris. The tumor was completely removed and pathological analysis was consistent with hemangioblastoma.  Conclusion. This report documents a unique location for extramedullary spinal hemangioblastomas. Although both MRI and myelography are helpful in studying these lesions, angiography remains the gold standard in differentiating between vascular tumor and malformation. We suggest that the angiography be performed by a neurointerventional team to facilitate embolization, should this be warranted.