Fractures of the atlas vertebra

In a series of 400 patients with fractures and dislocations of the cervical spine, 5% involved the atlas. There are nearly equal numbers of fractures of the posterior arch, bursting fractures of Jefferson, and horizontal fractures of the anterior arch. Atlas fractures are rarely associated with neurologic deficit, but they may be the cause of severe pain. Hypotheses concerning the mechanism of injury in each type of fracture are discussed. The characteristic roentgenographic findings and the differential diagnoses are reviewed.     

Cervical spine injuries in suicidal hanging without a long-drop—patterns and possible underlying mechanisms of injury: an autopsy study

Objectives

The incidence of cervical spine injuries in suicidal hangings with a short-drop has been reported to be extremely low or non-existent. The aim of this study was to determine the frequency and pattern of cervical spine injuries in suicidal hanging.

Methods

A retrospective autopsy study was performed and short-drop suicidal hanging cases with documented cervical spine injuries were identified. This group was further analyzed with regard to the gender and age of the deceased, the position of the ligature knot, the presence of hyoid–laryngeal fractures, and the level of cervical spine injury.

Results

Cervical spine injuries were present in 25 of the 766 cases, with an average age of 71.9 ± 10.7 years (range 39–88 years). In 16 of these 25 cases, the ligature knot was in the anterior position. The most common pattern of cervical spine injury included partial or complete disruption of the anterior longitudinal ligament and widening of the lower cervical spine disk spaces, associated with absence of hyoid–laryngeal fractures.

Conclusions

Cervical spine injuries are not commonly found in short-drop suicidal hanging, occurring in only 3.3 % of all observed cases. Cervical spine injury may be occurring in 80 % of subjects aged 66.5 years and above. The most common pattern of cervical spine injury included anterior longitudinal ligament disruption of the lower cervical spine, disk space widening, and no vertebral body displacement. These injuries were mainly associated with an anterior knot position, and may be a consequence of loop pressure to the posterior neck and cervical spine hyperextension.     

Hyperextension fracture-dislocation of the thoracic spine

Extension injuries of the thoracolumbar spine are rare and often are not included in classifications of thoracolumbar trauma. Hyperextension fracture-dislocation of the thoracolumbar spine is characterized radiographically by widening of the intervertebral disc space anteriorly. Additional features may include retrolisthesis, impaction fractures of the middle and posterior columns, and anterior inferior endplate corner fractures. Magnetic resonance imaging typically reveals rupture of the anterior longitudinal ligament and hemorrhage into the disc space, and it may demonstrate associated soft tissue or spinal cord injury. We present a case of hyperextension fracture-dislocation of the thoracic spine in a middle-aged female involved in a motor vehicle collision and discuss the salient features of this injury.     

The radiographic characterization of burst fractures of the spine

A retrospective review of 75 burst fractures of the spine was performed to define the radiographic features found on high-resolution CT, polytomography, and plain radiography and thereby allow full characterization of this uncommon spinal injury. Characteristic components of the injury include: centripetally oriented disruption of the vertebral body, unilateral or bilateral laminar fractures that abut the spinous process, marked anterior wedging, vertically oriented vertebral fracture emanating from the basivertebral foramen, increased interpediculate distance, and significant spinal canal narrowing by characteristic retropulsed fragments. Nearly all bursts occurred from T9 to L5; double bursts were present in less than 10% of cases. The usually present neurologic deficit nearly always corresponded to the level of the burst rather than to the frequently found noncontiguous associated spine fracture. Recent literature suggests that these complex fractures, which were initially thought to represent stable injuries, are often unstable. A subcategorization of burst fractures and their variants is proposed to explain this instability. An approach to the radiographic diagnosis of the spinal burst is proposed, and plain film clues to distinguish the burst fracture from the more common compression fracture are discussed. Representative cases are illustrated.     

Posterior longitudinal ligament status in cervical spine bilateral facet dislocations

Objective It is generally accepted that cervical spine bilateral facet dislocation results in complete disruption of the posterior longitudinal ligament. The goal of this study was to evaluate the integrity of numerous spine-stabilizing structures by MRI, and to determine if any associations between injury patterns exist with respect to the posterior longitudinal ligament status.Design Retrospective case series.Patients A retrospective review was performed of 30 cervical spine injury subjects with bilateral facet dislocation. Assessment of 1.5T MRI images was carried out for: intervertebral disc disruption, facet fracture, and ligamentous disruption. Statistical analyses were performed to evaluate for associations between various injury patterns and posterior longitudinal ligament status.Results The frequency of MRI abnormalities was: anterior longitudinal ligament disruption (26.7%), disc herniation or disruption (90%), posterior longitudinal ligament disruption (40%), facet fracture (63.3%) and disruption of the posterior column ligament complex (97%). There were no significant associations between injury to the posterior longitudinal ligament and other structures. Compared to surgical reports, MRI was accurate for determining the status for 24 of 26 ligaments (three of three anterior longitudinal ligament, seven of nine posterior longitudinal ligament, and 14 of 14 posterior column ligament complex) but generated false negatives in two instances (in both MRI showed an intact posterior longitudinal ligament that was torn at surgery).Conclusions In contradistinction to the existing concept, the posterior longitudinal ligament can remain intact in a substantial proportion of hyperflexion injuries that produce bilateral cervical facet dislocation. Posterior longitudinal ligament integrity is not associated with any other injury pattern related to the anterior longitudinal ligament, intervertebral disc or facet fracture.     

颈椎前路手术中相关神经损伤并发症的常见原因及治疗

目的 回顾颈椎前路手术中相关神经损伤的常见原因及治疗方法.方法 2008年1月-2009年12月手术治疗859例颈椎病、颈椎后纵韧带骨化症及颈椎外伤行颈椎前路手术患者,对术后出现脊髓损伤症状加重及相关神经损伤的7例患者的临床资料进行回顾性分析.结果 859例患者中共5例发生脊髓损伤,发生率为0.58%;1例发生喉返神经损伤,发生率为0.12%;1例发生喉上神经损伤,发生率为0.12%.术后血肿发生脊髓损伤4例,经过清除血肿、甲基强的松龙等药物、高压氧及时治疗,均逐渐恢复至正常;术后发生脊髓损伤症状加重1例,经气管切开、呼吸机支持治疗及激素、高压氧治疗后脊髓损伤症状逐渐恢复至原有水平.术后发生喉返神经、喉上神经损伤患者2例经过激素、脱水等药物保守治疗,术后3个月内均恢复至正常.结论 颈椎病、颈椎后纵韧带骨化症及颈椎外伤患者行颈椎前路手术中均可能发生脊髓损伤及相关神经损伤,如能注意预防和及时治疗,预后较好.

Abstract：

Objective To review the relevant causes for and treatment of nerve injuries in the anterior cervical surgery. Methods From January 2008 to December 2009,859 cages of cervical spondylosis,ossification of cervical posterior longitudinal ligament and cervical spine trauma were treated by anterior cervical surgery.This study retrospectively analyzed the clinical data of seven cases who were with worsened symptoms of spinal cord injury and related nerve injury. Results Of 859 cases,five cases(0.58%)were with spinal cord injury,one(0.12%)with recurrent laryngeal nerve injury and one (0.12%)with laryngeal nerve injury.Hematoma occurred in four cases after surgery caused spinal cord injury and all the four patients recovered to normal after removal of the hematoma and timely treatment with mythylprednisolone and hyperbaric oxygen.Cervical spine trauma was worsened in one patient after the anterior cervical surgery.The patient restored to its original level of spinal cord gradually through some measures such as tracheotomy,ventilator support,hormone therapy and hyperbaric oxygen treatment.Laryngeal nerve injuries in two cases recovered to normal after conservative treatment with hormone,dehydration and other drugs within three months after surgery. Conclusions Anterior cervical surgery of cervical spondylosis,ossification of cervical posterior longitudinal ligament and cervical spine trauma are likely to induce the related nerve damage.The good prognosis can be obtained under timely prevention and treatment.     

MRI of cervical spine injuries complicating ankylosing spondylitis

OBJECTIVE: The objective was to study characteristic MRI findings in cervical spine fractures complicating ankylosing spondylitis (AS). Technical issues related to MRI are also addressed. MATERIALS AND METHODS: A review of 6,774 consecutive cervical spine multidetector CT (MDCT) scans obtained during 6.2 years revealed 33 ankylosed spines studied for suspected acute cervical spine injury complicating AS. Of these, 20 patients also underwent MRI. RESULTS: On MRI, of these 20 patients, 19 had a total of 29 cervical and upper thoracic spine fractures. Of 20 transverse fractures traversing both anterior and posterior columns, 7 were transdiskal and exhibited less bone marrow edema than did those traversing vertebral bodies. One Jefferson's, 1 atlas posterior arch (Jefferson's on MDCT), 2 odontoid process, and 5 non-contiguous spinous process fractures were detectable. MRI showed 2 fractures that were undetected by MDCT, and conversely, MDCT detected 6 fractures not seen on MRI; 16 patients had spinal cord findings ranging from impingement and contusion to complete transection. CONCLUSION: Magnetic resonance imaging can visualize unstable fractures of the cervical and upper thoracic spine. Paravertebral hemorrhages and any ligamentous injuries should alert radiologists to seek transverse fractures. Multiple fractures are common and often complicated by spinal cord injuries. Diagnostic images can be obtained with a flexible multipurpose coil if the use of standard spine array coil is impossible due to a rigid collar or excessive kyphosis.     

Computer tomography in injuries of the cervical vertebrae

32 patients with traumatic injuries of the cervical spine were investigated by CT. All patients were initially examined by plain films. CT was definitely superior to conventional radiology in compressive fractures of vertebral bodies. In flexion-extension injuries CT was useful showing fractures of the posterior elements in great detail. Conventional tomography was superior to CT in patients with complex dislocations of vertebral bodies. In the absence of fracture CT failed to detect disruptions of ligaments, which were readily shown by functional examination.     

Spinal instability: the orthopedic approach

The determination of spinal stability remains an important task of the spine surgeon, as treatment strategies rely heavily on this assessment. However, a clinically useful definition of spine stability remains elusive. Numerous classification systems have been proposed: White and Panjabi proposed a checklist point system to assess spinal stability for each of the cervical, thoracic, and lumbar spines. This remains one of the best recognized systems to date. Denis proposed that spinal integrity depended on the three-column system (anterior, middle, and posterior) and used it to describe thoracolumbar fractures. The spine is considered unstable when any two of the three columns are disrupted. These two classification systems are designed for traumatic injuries and do not explain other causes of instability. In the end, numerous factors must be taken into account when determining spinal stability. These include the disease process causing the injury, the medical and neurologic status of the patient, the anatomic site, and findings on imaging studies.     

CT in the evaluation of spine trauma

Fifteen patients admitted for spine trauma in an 8 month period were studied with computed tomography (CT). All the patients had initial routine plain film screening, and 10 of 15 were also examined with conventional tomography. Five patients sustained vertical fall, axial-load injuries in the thoracolumbar junction region; two others suffered missile injury to the spine. CT provided more information than plain films in all these patients due to its superior imaging of bony detail and its ability to assess soft-tissue damage. In four of these patients, conventional tomography was done but contributed no additional information. Eight other patients sustained complex fractures of the cervical spine. In all but one, the combination of plain films and CT allowed complete evaluation of the injury. In one patient, conventional tomography showed an additional linear fracture one vertebral level below the main region of injury. Plain films and CT allow complete, safe, rapid, easily interpretable evaluation of spine trauma patients in the acute setting. Conventional tomography yields no additional clinically vital information in the acute evaluation of spine trauma, when plain films are abnormal. Its current ability to show finer bony detail than CT can be reserved for evaluating equivocal plain film and CT findings or more complete evaluation (if indicated) after the patient is clinically stable.     

急性颈椎外伤的MRI诊断

目的 分析急性颈椎外伤的MRI征象,评价MRI在急性颈椎外伤诊断中的价值及限度。方法收集急性颈椎外伤150例,均有MRI检查和X线平片,15例有CT片,采用14个参数进行分析记录。结果150例中MRI检出骨折51个,小关节脱位30个,椎体脱位35个;外伤性椎间盘突出40个,硬膜外血肿2例;脊髓损伤69例;脊髓受压迫20例;前、后纵韧带损伤21例;棘间韧带和黄韧带损伤15例;椎前血肿或水肿30例;椎旁和背侧软组织损伤40例;X线平片发现椎体骨折55个,椎体脱位35个;小关节脱位35例,附件骨折25个,椎前软组织肿胀20例。15例CT均发现骨折,小关节脱位,椎管狭窄。结论MRI在显示脊髓、韧带、椎间盘和软组织损伤方面优于CT和X线平片。MRI能全面反映颈椎各种损伤的病理特征,为评估颈椎稳定性提供充分的依据;MRI和X线片的骨折检出率没有明显差异,CT应该用于复杂的颈椎骨折检查。     

Roentgen examination of cervical spine injuries in the athlete

The roentgen evaluation of the cervical spine must be performed immediately following the possibility of injury and in such a manner as not to compromise the neurologic status of the patient. Subtle roentgen findings indicating ligamentous injuries must be recognized so that they can be treated prior to developing cervical spine instability. Occult fractures, which may be difficult to diagnose on plain films and require multiple radiographic modalities, must be diagnosed so as to prevent prolonged intractable neck pain. Most importantly, recognizing the mechanism of injury and prevention of cervical spine injuries are critical to prevent catastrophic cervical spine injuries secondary to athletic participation.     

MR evaluation of the "arcuate" sign of posterolateral knee instability

OBJECTIVE: The purpose of this study was to evaluate associated knee injuries using MR imaging in patients with the "arcuate" sign, a term referring to avulsion fracture of the proximal fibula on conventional radiographs. MATERIAL AND METHODS: MR imaging of 18 cases (17 patients, both knees in one patient) with the arcuate sign on conventional radiographs was retrospectively interpreted to evaluate the associated meniscal, ligamentous, and bony injuries. In 12 cases, MR findings were correlated with surgical results. RESULTS: In all cases, avulsed bony fragments from the proximal pole of the fibula were attached to the fibular collateral ligament, the biceps femoris tendon, or both. Tear of the posterolateral capsule was seen in 12 cases (67%). Injury of the cruciate ligaments was noted in 16 cases (89%): injury to both the anterior cruciate ligament and posterior cruciate ligament was seen in nine cases (50%), injury to only the anterior cruciate ligament was seen in four, and injury to the posterior cruciate ligament only was noted in three. Bone bruises or gross fractures were seen in all cases: bone bruises on the anteromedial femoral condyle were noted in nine cases (50%) and were seen on the anteromedial tibial condyle in five cases (28%). Tear of the medial meniscus was seen in five cases (28%) and tear of the lateral meniscus in four cases (22%). Injury to the popliteus was seen in six cases (33%). Joint effusion was associated in all cases. CONCLUSION: MR imaging is useful for evaluation of associated soft-tissue injuries in patients with the arcuate sign on conventional radiographs. Avulsion injury to the proximal fibula is an important indicator of the internal derangement of the knee and for predicting the mechanism of an injury with varus stress. Cruciate ligament tear and bone bruises on the anteromedial condyle of the femur and tibia are common associated findings.     

不稳性寰椎骨折的外科治疗策略

目的 探讨枕颈或寰枢椎内固定融合技术治疗不稳性寰椎骨折的临床疗效和应用价值.方法 对2004年10月-2009年3月收治的不稳性寰椎骨折38例进行回顾性分析,其中6例寰椎爆裂性骨折合并寰枕关节不稳(5例行C0～C2固定融合术,其中1例同时合并有C7椎体压缩性骨折行C0～C3固定融合术),7例典型的Jefferson骨折,3例半环骨折,8例寰椎骨折合并Ⅱ型齿状突骨折,3例寰椎骨折合并Hangman骨折(其中2例Levine-Edwards Ⅲ型行C0～C3固定融合术,1例Ⅱ型行C1～C2固定融合术),3例寰椎骨折合并下颈椎损伤,6例寰椎横韧带断裂(Dickman Ⅰ型)伴寰枢关节不稳,2例寰椎粉碎性骨折合并寰椎侧块内侧骨性结构附着处横韧带撕裂(DickmanⅡ型).5例行C0～C2固定融合术,3例行C0～C3固定融合术,30例行C1～C2固定术并行自体髂骨植骨融合.结果 所有患者术后均获得随访,平均随访时间为28个月(12～46个月).临床症状均得到不同程度的改善.平均手术时间135 min(80～190 min),平均失血量460ml(200～3 300 ml),平均透视时间60 s.38例患者术中均未发生神经、椎动脉和其他手术相关并发症.全部患者均于术后3 d颈托固定后下地行走;术后脊髓损伤症状无加重.3例因电刀灼伤C1～C2间血管静脉丛导致出血,行止血纱布、脑棉片填塞止血,未出现颅脑缺血症状.复查X线片和CT未发现上颈椎失稳或复位丢失,螺钉位置良好,无松动、断钉,寰枢椎或枕颈部均获骨性融合.在晚期随访中,4例(11%)有颈部疼痛和僵硬感,1例枕神经痛.结论 对具有不稳定性寰椎骨折或合并寰椎横韧带损伤的患者,采用枕颈或寰枢椎内固定融合技术及短期外固定对于重建上颈椎永久稳定性是较好的手术方式,并且能阻止神经和脊髓功能的进一步损伤.

Abstract：

Objective To evaluate the clinical effect and safety of the occiput-cervicle or C1-C2 internal fixation and bone graft fusion in treatment of the unstable atlas fracture.Methods A retrospective study was performed in 38 patients with unstable atlas fractures treated by the occiput-cervicle or C1-C2 internal fixation and bone graft fusion from October 2004 to March 2009.Six patients with comminuted atlas fracture combined with instability of the occipito-atlantoid articulations were treated with occiput-C2 fusion(five patients)and with occiput-C3 fusion(one patient).There were seven patients with typical Jefferson fractures,three with semiring fractures,eight with atlas fractures combined with Anderson type Ⅱ odontoid process fractures,three with atlas fractures combined with Hangman's fractures (two patients with Levine and Edwards type Ⅲ Hangman's fractures were treated with occiput-C3 fusion and one patient Levine and Edwards type Ⅱ Hangman's fracture was treated with C1-C2 fusion),three with atlas fracture combined with lower cervicle injury,six with rupture of transverse ligament combined with instability of atlanto-axial joint(Dickman transverse ligament type Ⅰ injury)and two with comminuted fracture of the lateral mass associated with bony avulsion of the medial tubercle and transverse ligament(Dickman transverse ligament type Ⅱ injury).Of all,five patients were treated with occiput-C2 fusion,three treated with occiput-C3 fusion and 30 treated with C1-C2 fusion.Results All the patients were followed up for a range of 12-46 months(average 28 months),which showed improvement of clinical symptoms in some extent postoperatively.The operation time ranged from 80 to 190 min ates(average 135 minates),with intraoperative blood loss for 200-3 300 ml(average 460 ml)and average fluoroscopic time for 60 seconds.There were no neurological deficits,vertebral artery related complications or other complications in all the patients during the surgical operation.No neurological deficit was aggravated after the patient's mobilization with brace three days after operation.The enous plexus of blood vessel at C1-C2 rupture induced by the use of electrocautery was found in three patients who showed no cerebral hemodynamic deficit after hemostasis with hemostatic sponge and cotton piece.The follow-up X-ray and CT manifested osseous fusion in all the patients,with no looseness or breakage of the screws.The late follow-up showed pain associated with movement and limited range of motion in four patients(11%)and occipital neuralgia in one.Conclusions An occiput-cervicle fixation fusion or a C1-C2 fixation fusion combined with short external fixation can reestablish the upper cervical stability and prevent further injury of the spinal cord and nerve function and hence is an ideal option for C1 burst fracture with or without rupture of the transverse ligament.     

Calcification of the alar ligament of the cervical spine: imaging findings and clinical course

Ligamentous calcification of the cervical spine has been reported in the yellow ligament, anterior and posterior longitudinal ligaments and interspinous ligament. Calcification in the upper cervical spine is rare, although some cases with calcification of the transverse ligament of the atlas have been reported. Two patients with calcification of the alar ligament with an unusual clinical presentation and course are described. Examination by tomography and computed tomography (CT) showed calcification of the alar ligament and the transverse ligament of the atlas. CT documented decreased calcification as symptoms resolved. There may be a role for CT in the search for calcifications in the upper cervical spine in patients presenting with neck pain and pharyngodynia if radiographs are normal. Received: 13 October 2000 Revision requested: 17 November 2000 Revision received: 18 December 2000 Accepted: 19 December 2000     

Magnetic resonance imaging of ligamentous injury of the cervical spine

This study is a retrospective review of 43 patients with acute cervical spine trauma, including 97 ligamentous injuries of various types diagnosed by magnetic resonance imaging (MRI). Three general patterns of ligamentous injury were observed, including: complete rupture; partial avulsion or attenuation of the ligament, without frank rupture; and combined osseous and ligamentous fragment. Overall, proton density and T2^*-weighted gradient-echo or T2-weighted spinecho images in the sagittal plane provided the best evaluation of the spinal ligaments. Axial proton density and T2^*-weighted gradient images were useful only in assessment of the trasverse portion of the cruciate ligament. By providing direct visualization of the spinal ligaments, MRI demonstrated multiple case of ligamentous injury that were greater than expected or unexpected from plain radiographic and computed tomographic findings. Surgical proof was obtained for 11 patients with 14 ligamentous injuries that were diagnosed by MRI independently. There were two false-positive MRI diagnoses for posterior longitudinal ligament rupture, but no false-negatives among these 11 patients. This study indicates that MRI allows accurate diagnosis of cervical spine ligamentous injuries that are otherwise only inferred by the mechanism of injury and resulting spinal alignment.     

The value of plain radiographs in the prediction of outcome in pelvic fractures treated with embolisation therapy

40 haemodynamically unstable patients with pelvic injuries were studied to assess the ability of plain radiographs to detect haemorrhagic sites. Pelvic radiographs and bilateral angiograms were reviewed separately for detection of haemorrhagic sites in both anterior and posterior segments. Sensitivity and specificity of pelvic radiographs for the detection of haemorrhagic sites were obtained by analysis of angiographic findings. Angiography demonstrated arterial injury in 106 divisions: 26 right anterior, 22 right posterior, 33 left anterior and 25 left posterior. Sensitivities of the radiographs for predicting haemorrhagic sites were higher in the anterior segment (right, 96%; left, 100%) than in the posterior segment (right, 73%; left, 83%). However, specificities were lower in the anterior segment (right, 79%; left, 78%) than in the posterior segment (right, 100%; left, 100%). In 15 (58%) of 26 patients with in-dwelling Foley catheters, including those with catheter deviation, the severity of anterior injury indicated on plain radiographs was correlated with angiographic findings. Plain radiographs of the pelvis proved useful for predicting haemorrhagic sites in haemodynamically unstable patients with pelvic fractures, especially in those with anterior fractures.     

Case report: lethal fetal head injury and placental abruption in a pregnant trauma patient

Fetal trauma in blunt abdominal trauma is uncommon, but traumatic fetal head injury is almost universally fatal to the fetus. Placental abruption is the most common injury to the gravid uterus in trauma, and when the mother survives, it is the most common cause of fetal death. The imaging diagnosis of these conditions may be difficult since there are only three cases reported in the literature of intrauterine skull fractures on plain films [3, 8, 10], ultrasound is in sensitive in the diagnosis of placental abruption [24], and the most sensitive test to diagnose placental abruption is external fetal monitoring with devices that measure uterine tone and contractility and fetal heart rate [23]. The diagnosis of fetal trauma and placental abruption may be made on contrast enhanced CT performed through the abdomen and pelvis of pregnant trauma patients. For these reasons, it is useful for the radiologist interpreting the CT scan to recognize fetal head injuries and placental abruption in pregnant trauma patients.Fig. 7 Axial scans through the bony pelvis demonstrate an unstable pelvic fracture with posterior pelvic ring disruption.There is a zone 2 fracture of the left sacrum and a fracture of the left obturator ring (arrowheads)     

Malformations of the atlas vertebra simulating the Jefferson fracture

Congenital clefts and aplasias of the atlas vertebra, while rare, are often first encountered in the emergency room setting. Thirty-six patients with atlas malformations and 10 with Jefferson fractures were encountered. Sixteen of the patients with congenital malformations showed bilateral atlantoaxial lateral offset, a finding generally considered to be the result of fracture. The diagnosis of these abnormalities is readily made from plain films by noting their characteristic features. Anomalies produce lateral offset of 1-2 mm. Jefferson fractures produce a greater offset (over 3 mm).