Imaging of cervical spine trauma: are the anteroposterior and odontoid radiographs needed when CT of the entire cervical spine is routine?

Objective: To evaluate the contribution of the anteroposterior (AP) and odontoid radiographs in cervical spine trauma when helical CT of the entire cervical spine is performed in routine screening. Methods: In part 1 of the study, 47 patients with cervical spine fracture (positive) and 92 patients without fracture (negative) were retrospectively assembled into a study population. For each patient, the lateral radiograph and the CT were evaluated for the presence or absence of fracture. The results were compared to the radiology report at the time of injury which was based on the lateral, AP, and odontoid radiographs plus the CT (gold standard). In part 2 of the study, the individual sensitivities of CT and each radiograph were determined by review of the 47 positive patients with the fracture locations known a priori. Results: In all 47 positive patients, the presence of fracture was correctly identified using only the lateral radiograph and the CT. In none of the 92 negative patients was the lateral radiograph plus CT incorrectly interpreted as positive for fracture. The sensitivities for fracture of CT, the lateral radiograph, the AP radiograph, and the odontoid radiograph were 100, 47, 28, and 18 % respectively. Conclusion: The AP and odontoid radiographs did not contribute to the evaluation of suspected cervical spine fracture when the lateral radiograph and helical CT of the entire cervical spine were performed in routine screening.     

上颈椎创伤诊治:重要理念回顾与常见误区分析

上颈椎指颅颈交界区域,包括3个椎节(枕骨髁、寰椎和枢椎)与2个椎间关节,由于贡献了近一半的颈椎活动度,上颈椎易于损伤。上颈椎解剖结构复杂,功能重要,具有特殊的运动学特征,导致其创伤的诊治具有挑战性。基于文献及作者的临床实践,本文旨在为读者回顾上颈椎创伤诊治过程中的关键点,并分析常见的失误。笔者建议在整个诊治过程中,应该重点关注骨折愈合的可能性,以及椎间关节功能(稳定与节段间运动)恢复的可能性。     

Anterior cervical subluxation: an unstable position.

The radiologic signs of cervical anterior subluxation are subtle. Even when recognized, the injury may not be considered significant. However, anterior subluxation is the most unstable cervical spinal injury. The two case histories illustrate instability of the cervical spine in this type of injury. The radiologically diagnostic features on the lateral radiograph are described and the recognition of instability on mobility studies is discussed.     

Chronic repetitive unrecognized flexion injury of the cervical spine (high jumper's neck)

Unrecognized flexion injuries of the cervical spine may lead to late instability and neurologic damage. These hidden flexion injuries may be from acute or chronic traumatic episodes. Cervical spine instability was seen in an amateur high jumper as a result of chronic repetitive flexion loading of her cervical spine due to incorrect landing technique. The instability from these types of flexion injuries is generally unrecognized on a routine lateral radiograph. The presence of slight anterior subluxation, simple compression fractures, or subtle kyphotic angulation at one cervical level should alert the physician to this diagnosis. Flexion extension views are useful to demonstrate this instability. Occupations and sports which involve repetitive flexion stress to the cervical spine are at risk for this type of late instability. Therefore, in high jumping careful attention to safe techniques of landing is of utmost importance.     

Occipitocervical subluxation

Although rare, occipitoatlantal subluxation should be recognized on the lateral cervical spine radiograph.     

Routine preoperative biliary drainage: effect on management of obstructive jaundice

Dens fractures are frequently difficult to identify radiographically, particularly when it is only possible to obtain a lateral radiograph of the upper cervical spine. Further, when a dens fracture is identified in lateral projection, it is often difficult to distinguish the "high" (Type II) from the "low" (Type III) fracture. The authors describe an elongated "ring" density superimposed upon the body of the axis in the lateral cervical radiograph which, when horizontally disrupted, indicates a dens fracture and is a specific radiographic sign of the "low" variety.     

Current role of lateral cervical spine radiograph: a case report

We report a case showing the classic features of a Hangman's cervical spine fracture following a motor vehicle collision. Because this injury was not diagnosed at ED presentation, this case also illustrates the select subset of trauma patients for whom the almost obsolete lateral cervical spine radiograph remains an important part of the radiographic trauma series.     

Achalasia presenting on a lateral cervical spine radiograph of a trauma patient

We present a case in which the diagnosis of esophageal obstruction was suggested on a lateral radiograph of the cervical spine obtained after a motor vehicle accident.     

不同机种飞行人员颈椎曲度改变的特征探讨

目的　探讨歼、强击机和运输、轰炸机飞行人员颈椎生理曲度改变特征。方法　在颈椎侧位片上 ,测量各椎体曲度值 ,并与参考常值作比较。结果　在 2 0～ 2 9岁范围内 ,歼、强击机飞行人员颈椎曲度异常发生率为 5 9.2 %,运输、轰炸机飞行人员颈椎曲度异常发生率为 14 .3%;在 30～ 39岁范围内 ,歼、强击机飞行人员颈椎异常发生率为 83.3%。运输、轰炸机飞行人员颈椎异常发生率为 75 %。结论　歼、强击机飞行员颈椎曲度异常率高于运输、轰炸机 ;各机种年龄大的飞行员颈椎曲度异常率高于年轻飞行员。     

中颅窝凹陷度与颈椎张口位环枢关节显示效果的相关性研究

目的探讨中颅窝凹陷度与颈椎张口位X线片环枢关节显示效果的相关性。方法①收集标准颈椎张口位影像200例,同时照有颈椎侧位影像。②中颅窝凹陷度测量方法：在颈椎侧位影像上,连接上颌门齿下缘与枕骨下缘,测量第1、2颈椎间隙到连线的垂直距离,第1、2颈椎间隙位于连线下方的为正值,位于上方的为负值。③张口位影像评价测量方法：在标准张口位影像中,测量环枢关节颈1关节面连线中点到上颌门齿下缘的距离,连线位于上颌门齿下缘上方的为负值,相反的为正值。④评价中颅窝凹陷度测量数值与张口位影像测量数值的相关性。⑤评价中颅窝凹陷度测量数值与颈椎张口位环枢关节显示效果的相关性。结果①中颅窝凹陷度测量数值与张口位影像测量数值存在相关性。②当中颅窝凹陷度测量数值距离〉2 mm时,张口位影像环枢关节显示良好;当距离〈2 mm时,齿状突显示欠佳;而当测量数值接近0或负值时,环枢关节与上颌门齿和枕骨重叠,显示不清。结论中颅窝凹陷度对颈椎张口位影像显示效果具有相关性,当中颅窝凹陷度数值为0或负值时,张口位环枢关节与上颌门齿和枕骨重叠,显示不清。     

Predicting radiology resident errors in diagnosis of cervical spine fractures

RATIONALE AND OBJECTIVES: Our objective was to identify factors associated with resident errors of cervical spine fractures to enable targeted education. MATERIALS AND METHODS: We performed a retrospective cohort study of consecutive cases of after-hours resident interpreted cervical spine fractures over 27 months at a single level 1 academic trauma center. The outcome measure was appropriate identification of all fractures by the resident. Potential predictors of resident error or discrepancy were identified from chart review and included: age, gender; fracture location/pattern (upper/lower cervical spine, occipital condyle, C1 ring, dens, C2 pars, vertebral body, posterior column, lateral mass, transverse process); consecutive and nonconsecutive additional fractures; radiologist distracting factors (number of noncervical spine injuries); number of noncervical spine studies performed. Risk ratios with confidence intervals were calculated for categorical variables using epidemiological 2 x 2 tables, and for continuous variables using difference of means. RESULTS: There were 59 errors among 492 cervical spine fractures in a total of 327 patients. Fifty-seven of the errors were on computed tomography and 2 errors were on radiographs. Upper cervical fractures were significantly more likely to have been errors than lower cervical fractures: risk ratio (RR) of 2.2 (confidence intervals (CI) 1.3, 3.5; P = .001). Occipital condyle fractures were more likely to have been discrepant: RR = 2.2 (CI 1.3, 3.9; P = .006). Dens fractures were also significantly more likely to have been discrepant: RR = 2.0 (CI 1.0, 3.8; P = .05). Other potential predictors were not associated with significantly increased risk. CONCLUSION: Upper cervical spine fractures, in particular occipital condyle and dens fractures were significantly associated with an increased relative risk of resident missing or misinterpreting the fracture. These findings suggest that resident education should focus in particular on upper cervical spine injuries, occipital condyle, and dens fractures. The methods used in this study could also be applied to other imaging modalities and anatomic regions in the future to target resident education to more challenging areas.     

Can CT eliminate the initial portable lateral cervical spine radiograph in the multiple trauma patient? A review of 200 cases

Purpose: This investigation examines whether there is a continued role for the initial screening lateral portable radiograph in patients whose cervical spine is “cleared” by a CT examination. Methods: A retrospective review of 200 multiple trauma patients suspected of cervical spine injury (CSI) was performed. All patients had a screening lateral portable cervical spine radiograph (LPCSR) followed by cervical spine CT (CSCT). All scans were helical and included coronal and sagittal reformations. Reports of both examinations were compared for all patients. For those patients with signs of acute CSI, the two reports were compared to determine whether the LPCSR contained any information affecting patient outcome that was not detected by CSCT. Results: The CSCT showed no signs of acute CSI injury in 190 patients. Ten CSCT scans showed signs of fracture. In these 10 patients, the screening LPSCR showed signs of fracture in 1 patient, question of fracture in 2 patients, and no fracture in 7 patients. No LPCSR demonstrated significant information not seen on the accompanying CSCT. No LPSCR showed a finding that altered patient management prior to CSCT. Conclusion: The data suggest that an initial LPCSR is unnecessary if the patient is having a screening CSCT.     

枕骨髁骨折的多层螺旋CT诊断

目的 分析枕骨髁骨折的MSCT表现,提高对头颈部外伤患者枕骨髁骨折的诊断水平.方法 对110例头颈交界区骨折患者进行回顾性分析,发现枕骨髁骨折19例(17%);由2名骨放射专家独立对枕骨髁的MSCT表现进行评价.分型标准:Ⅰ型,枕骨髁粉碎性骨折;Ⅱ型,颅底广泛的骨折延伸至枕骨髁部;Ⅲ型,枕骨髁翼状韧带附着部撕脱骨折;Ⅳ型为混合型,即Ⅰ～Ⅲ型中的2型或2型以上骨折同时存在.结果 19例枕骨髁骨折中,左侧7例,右侧11例,双侧1例.枕骨髁骨折1型1例,骨折位于左侧.Ⅱ型5例,左侧2例,右侧3例,主要为枕骨髁后份和中份受累.Ⅲ型12例,右侧8例,左侧3例,双侧1例;撕脱骨片多数不同程度移位,并且6例骨折线累及关节面,7例翼状韧带增粗.Ⅳ型1例,为Ⅱ型和Ⅲ型枕骨髁骨折同时存在.枕骨髁骨折伴随征象:14例枕骨髁骨折患者分别或同时存在头部和颈椎损伤,包括颅骨骨折8例,硬膜外血肿4例,蛛网膜下腔出血1例,脑挫裂伤1例,颅内积气、大脑镰下疝1例及颈椎骨折脱位9例等.结论 MSCT对枕骨髁骨折能够作出及时、准确的影像学诊断,对于临床选择治疗方案非常重要.

Abstract：

Objective To explore the MSCT findings of occipital condyle fracture (OCF) and improve its diagnostic accuracy. Methods Nineteen patients with OCF, selected from 110 patients suffering high energy injuries at the craniocervical junction, were enrolled into the study. The MSCT appearances of OCFs were retrospectively analyzed by two experienced radiologists. OCF had four types: type Ⅰ was a comminuted fracture, type Ⅱ was a extension of basilar skull fracture, type Ⅲ was an avulsion fracture at the attachment site of alar ligament on occipital condyle, type Ⅳ was a fracture of mixed pattern consisting of two or more above fracture types. Results In 19 patients, the left, right and bilateral OCFs were seen in 7,11 cases, and 1 case, respectively. Type Ⅰ was found in one case, which was a comminution of the left occipital condyle. Type Ⅱ was found in 5 cases, which involved the middle and posterior parts of occipital condyles with 2 on the left and 3 on the right, Type Ⅲ was found in 12 cases which showed various degree of fragment displacement with 3 occuring on the left, 8 on the right, 1 involving bilateral sides, 6 involving articular surfaces and 7 accompaning by enlargment of alar ligaments. Type Ⅳ was found in one case, with coexistence of Type Ⅱ and type Ⅲ. In addition, OCFs were accompanied by head and (or) cervical spine injuries in 14 cases, which included cranial fracture in 8 cases, epidural hematoma in 4 cases, subarachnoid hemorrhage in one case, cerebral contusion and laceration in one case, subfalcial hernia in one case, cervical spine fracture and dislocation in 9 cases, and so on. Conclusion OCFs can be accurately diagnosed by MSCT, which is important for selection of treatment protocols.     

Elongation of the anterior tubercle of a cervical vertebral transverse process: An unusual variant

Elongation of the anterior tubercle of a transverse process of a cervical vertebra is a congenital anomaly that should be considered in a patient demonstrating a bony mass projecting anterior to the vertebral body on a lateral radiograph of the cervical spine. Reported is a case of elongation of the tubercles of the transverse processes of both C5 and C6 with the formation of an articulation. Computed tomography was used to definilation. Computed tomography was used to definitively differentiate this variant from a fracture fragment, bone tumor, or osteophyte. This anomaly is probably a form of supernumerary cervical rib developing at a level above the lowest cervical vertebra.     

Cervical spine injury seen only on an upright lateral view

This report describes a case in which significant cervical spine injuries were demonstrated only on the upright lateral view. On occasion, unstable or potentially unstable cervical spine injuries may only be seen on an upright lateral view.     

The chance fracture: Anteroposterior radiographic signs

Chance fractures and their ligamentous equivalents may be readily diagnosed on lateral radiographs of the thoracolumbar spine, but often, the lateral view is of insufficient diagnostic quality in the emergency setting. It is imperative, therefore, to recognize the findings of Chance injuries on the anteroposterior view of the spine. This pictorial essay emphasizes the various manifestations of the Chance fracture on the anteroposterior radiograph, an understanding of which is facilitated by a review of the mechanism of this injury.     

Traumatic retropharyngeal hematoma and prevertebral edema induced by whiplash injury

Whiplash injury commonly results in cervical spine trauma. We report a case of a 58-year-old man, who sustained a whiplash injury from contact with the headrest of his seat after his car was involved in a rear-end collision. He presented with sore throat, hoarseness, difficulty in swallowing and progressing dyspnea. The diagnostic work-up comprising lateral radiograph, CT and MR imaging disclosed the rare constellation of a retropharyngeal hematoma and prevertebral edema without further injury of the cervical spine structures. Compression of the upper airways was evident. A careful history and an appropriate diagnostic approach are essential for the work-up and management of such a life-threatening situation.     

Effect of a full and empty bladder on radiation dose to the uterus, ovaries and bladder from lumbar spine CT and X-ray examinations

This is a quantitative study of the effect of a full and empty bladder on the position of the uterus, ovaries and bladder relative to the lumbar spine. Data are used to estimate the difference in radiation dose to these organs from performing a lumbar spine CT investigation or a lateral lumbar spine radiograph with a full bladder compared with an empty bladder. 12 women of child-bearing age underwent pelvic magnetic resonance scans with full and empty bladders. The positions of the uterus, ovaries and bladder were matched with the radiation dose distribution that would have occurred either side of the inferior boundary of the CT scan volume and the lateral lumbar spine radiograph. These radiation dose profiles were measured on phantoms using a combination of ionization chambers and thermoluminescent dosemeters. When the bladder was emptied, the mean position of the endometrial cavity fundal tip moved from 4.1 cm to 6.1 cm inferior to the centre of the L5/S1 disc space, and from 0.87 cm to 1.12 cm anterior to the centre of the L5/S1 disc space. This movement on micturation would have reduced the mean dose to the uterine internal fundal tip during a pelvic CT scan from 6.8 mGy to 3.9 mGy, which represents a mean reduction of 43% (range 12-67%). The mean dose from a lateral lumbar spine examination would have been reduced from 197 microGy to 126 microGy. The change in ovary position results in the mean ovary dose being reduced by 48% for the lumbar spine CT scan and by 43%) for a lateral lumbar spine radiograph. When the bladder was emptied, the average position of the bladder wall moved from 7.2 cm to 10.3 cm inferior to the L5/S1 disc space. This change in bladder position reduces the mean dose to the wall of a full bladder from 5.7 mGy for a CT scan and 114 microGy for a lumbar spine radiograph to 2.2 mGy and 42 microGy, respectively, for an empty bladder.     

The opisthion on the lateral radiograph of the cervical spine.

Ten adult dry skulls were radiographed in the lateral projection to evaluate the appearance of the opisthion, the posterior margin of the foramen magnum. The opisthion was seen on all 10 skulls and its position was confirmed by outlining it with barium paste. In cross section, it is a teardrop-shaped structure continuous with the internal occipital crest. A beak-shaped shadow anterior to the opisthion was also examined with the barium technique. It is an overlap shdow formed by the interior margin of the foramen magnum and the inferior border of the occipital bone on the same side. In a review of 50 random radiographs of the cervical spine, the opisthion was identified on 42 (84%) and the beak-shaped overlap shadow was seen on 28 (56%). The spinolaminal line, which delineates the posterior margin of the cervical spinal canal, was an unreliable indicator of the position of the opisthion in 17 (40%) of the 42 cases in which the opisthion could be identified.     

Isolated fracture of the medial portion of the lateral mass of the atlas: a previously undescribed entity.

Four cases of fracture of the medial aspect of the lateral mass of the atlas are presented. Unlike most cases of atlantal fracture, definite history of a blow to the vertex could not be established. While the exact mechanism of injury is unknown, it is postulated that the bone fragment is produced by a combination of stretching the ligamentum transversarium and pressure on the lateral mass due to contraction of the neck muscles. All four patients were neurologically intact and complained of pain in the distribution of the greater occipital nerve. It is suggested that this fracture might be identified more often in patients with similar histories and complaints by use of laminagraphy, since part or all of the atlas is frequently obscured on routine open mouth roentgenograms of the upper cervical spine.