Mechanical contributions to chronic lateral ankle instability

Lateral ankle sprains are one of the most common athletic injuries. Even more concerning is the high recurrence rate after an initial sprain. The development of repetitive ankle sprains and persistent symptoms after injury has been termed chronic ankle instability (CAI). One of the purported causes of CAI is mechanical ankle instability (MAI).MAI results in abnormal ankle mechanics. Both hypermobility and hypomobility may change a joint's axis of rotation and result in abnormal joint mechanics. The role of hypermobility, or laxity, has been examined extensively in the literature, but more recently the role of hypomobility has also been examined. There may be a relationship between the two, with implications at the talocrural, subtalar, and inferior tibiofibular joints.Assessment and treatment should focus on both hypermobility and hypomobility and although injury may seem to be isolated to the talocrural joint, the inferior tibiofibular and subtalar joints should also be thoroughly examined.     

Quantification of C2 cervical spine rotatory fixation by X-ray,MRI and CT

Atlanto-axial rotatory displacement is known to be a cause of childhood torticollis and may as well be responsible for chronic neck pain after rear-end automobile collisions. The objective was to determine whether quantification of C2 malrotation is possible by plain radiographs in comparison to CT as the golden standard. MR imaging was evaluated as to whether it was of equal value in the detection of bony landmarks. C2 vertebra of five human cadaveric cervical spine specimens, ligamentously intact, were rotated using a Steinmann pin in steps of 5° up to 15° right and 15° left. Plain radiographs, CT and MRI images were taken in each rotational step. Data were analyzed for quantification of C2 rotation by three independent examiners. A rotation of 5° led to a spinous process deviation (SPD) from the midline of 3 mm as measured on an a.p. plain radiograph. A coefficient of rotation was calculated (1.62° mm^–1). Data analyzed by three examiners revealed a small coefficient of variation (0.03). MRI and CT measurements showed comparable results for the quantification of rotation; however, in both techniques the 15° rotation was underestimated. Quantification of upper cervical spine malrotation was possible on plain radiographs using the SPD and a rotation coefficient. MRI and CT were equally successful in the assessment of C2 malrotation.     

Is there an association between fractures of the cervical spine and first- and second-rib fractures?

OBJECTIVE: To investigate a potential association between cervical spine injury and first- and second-rib fractures. METHODS: Retrospective review of the radiologic and medical records of 28 consecutive patients admitted to an acute spinal injury unit. RESULTS: A total of 10 (36%) of the patients with cervical spine trauma also had fractures of either the first or second ribs. Eight of these 10 patients had a fracture or fracture-subluxation of the seventh cervical vertebra or the C6/7 segment. CONCLUSION: Almost one-third of patients with traumatic cervical spine injury have an associated upper-rib fracture. The strongest association is between injury at the C7 level and first-rib fracture.     

The rotational component in the dynamics of the C2-3 spinal segment.

The technique of the PA axial projection of the arches of the upper cervical vertebrae into the occipital foramen and the normal findings, are described. The influence of maximum forced anteflexion at the craniocervical junction and rotation of the head on the relations of atlas and axis is demonstrated. It seems that in this position rotation at atlas-axis level is restricted and partly transmitted to the C2-3 segment. Thus, selective clinical examination of the rotational component of the dynamics at C2-3 can be achieved and the pathological restrictions of movement can be assessed.     

The rotational component in the dynamics of the C2–3 spinal segment

Summary The technique of the PA axial projection of the arches of the upper cervical vertebrae into the occipital foramen and the normal findings, are described. The influence of maximum forced anteflexion at the craniocervical junction and rotation of the head on the relations of atlas and axis is demonstrated. It seems that in this position rotation at atlasaxis level is restricted and partly transmitted to the C_2–3 segment. Thus, selective clinical examination of the rotational component of the dynamics at C_2–3 can be achieved and the pathological restrictions of movement can be assessed.     

老年上颈椎损伤的临床特点与治疗

目的 探讨老年上颈椎损伤的临床特点与治疗方法.方法 回顾性分析我科2003年1月-2007年12月间收治的>60岁上颈椎骨折脱位患者28例的临床资料,其中男20例,女8例;年龄60～86岁,平均68.1岁.致伤原因:跌伤16例,交通伤8例,高处坠落伤4例.寰椎骨折5例;枢椎骨折15例,其中齿状突骨折8例,C2椎弓骨折6例,C2椎体骨折1例;寰枢椎损伤伴下颈椎损伤5例;寰枢椎同时损伤2例,其中齿状突骨折伴寰椎侧块骨折1例,齿状突骨折伴寰椎前弓骨折1例;寰枢关节脱位1例.并发脊髓损伤4例.保守治疗8例,开放手术治疗8例,微创经皮手术治疗12例.结果 平均住院时间比较,保守组与传统手术组间差异无统计学意义(P>0.05),而微创经皮组短于保守组与传统手术组(P<0.05).保守治疗组2例死亡,开放手术组1例死亡,其余25例均获得随访,随访时间9～56个月,平均16.8个月.保守治疗组患者满意率为50%,开放手术组为72%,微创手术组为75%.保守治疗组中4例发生并发症,传统手术组3例,微创手术组2例.结论 老年上颈椎损伤发生率较高,其损伤特点以低能量暴力为主,损伤类型以齿状突骨折最常见,具有脊髓损伤发生率低、漏诊率高等特点.在排除手术禁忌证的情况下,手术治疗特别是微创手术可取得较好的临床疗效.     

经高位咽后入路行上颈椎手术的治疗选择

目的 观察经高位咽后入路行上颈椎前路手术的适应证选择及临床效果. 方法 本组男32例,女9例;年龄12～67岁,平均41岁.Hangman骨折21例,C2椎体骨折2例,先天性齿状突不连伴难复性寰枢椎脱位12例,C1,2椎体结核4例,C3骨巨细胞瘤2例.全部患者均采用高位前方咽后入路显露C1～C3,Hangman骨折和C2椎体骨折复位后行C2,3椎间盘切除植骨融合内固定;先天性齿状突不连行前路松解复位、后路寰枢融合;结核行病灶清除,肿瘤行切除重建.创伤患者脊髓损伤按美围脊髓损伤学会(ASIA)标准评定,非创伤患者依据日本骨科学会(JOA)评分、Odom标准评定神经功能. 结果 41例患者均成功显露C1前弓～C3椎体,骨折患者行复位减压融合内固定;结核、肿瘤患者行病灶切除重建.创伤患者脊髓功能正常者无神经功能损害,不全瘫患者神经功能均有部分恢复.非创伤患者神经功能有明显改善,JOA评分由术前8.9分增加至12.5分;Odom评分临床成功率(优/良/可)达到94%.3例出现舌下神经牵拉症状,2例出现面神经刺激症状,无伤口感染. 结论 前方高位咽后入路可充分显露上颈椎,完成复位减压和稳定重建,并最大限度重建颈椎生理功能.     

Evaluation of acute cervical spine imaging based on ACR Appropriateness Criteria?

The objectives of this study were to determine the rate of acute blunt cervical spine injury at an academic urban level 1 trauma center and to evaluate the utilization of cervical spine imaging based on the established American College of Radiology (ACR) Appropriateness Criteria?. We retrospectively reviewed all radiography and CT imaging of the cervical spine performed over a year period in adult patients presenting with acute blunt cervical spine trauma. Exclusion criteria were children ≤17 years, non-acute trauma of ≥72 h, and penetrating trauma. Any fracture, dislocation, or ligamentous instability demonstrated by diagnostic imaging and requiring stabilization or specialized follow-up was defined as clinically significant cervical spine injury. A total of 1,325 cervical spine studies were reviewed in 1,245 patients; 32.7% (433/1,325) were cervical spine radiographs and 67.3% (892/1,325) were CT examinations. Approximately 1.5% (19/1,245) of the patients demonstrated clinically significant acute cervical spine injury. There were 6.4% (80/1,245) patients who received both cervical spine radiographs and CT as imaging evaluation. Based on the ACR Appropriateness Criteria?, all of the cervical spine radiographs performed (433) were determined to be “inappropriate” imaging in the setting of acute cervical spine injury.     

CT angiographic evaluation of the V3 vertebral artery course in cases of occipitalized atlas,a study of 25 cases

ObjectivesTo study the relationship of the 3rd segment of the vertebral artery to the posterior arch of the atlas in patients with occipitalized atlas, using CT angiography.MethodsA retrospective study of 25 cases with complete or partially occipitalized atlas who underwent CT angiography evaluation. Fifty vertebral arteries were analyzed in relation to the respective/related half of the posterior arch of the atlas.ResultsOut of 50 vertebral arteries, 35 (70%) were anomalous; 31 (62%) traversed though bony canal between the fused occiput and atlas, and 4 (8%) coursed between C1 and C2 (C2 segmental type of vertebral artery). Except one, all anomalous vertebral arteries were associated with a fused corresponding side of posterior arch of atlas.ConclusionThe V3 portion of the vertebral artery assumes an anomalous course at the craniovertebral junction in most cases of occipitalized atlas, and this is strongly determined by the fusion status of the posterior arch of the atlas. Aberrations in its course are still seen despite expectations based on this fusion status. Preprocedural CT Angiography provides accurate information of its course to prevent iatrogenic VA injuries.Advances in knowledgeCT Angiography should be performed before any procedures at the craniovertebral junction in cases of occipitalized atlas to prevent iatrogenic, potentially catastrophic injuries to vertebral artery due to its anomalous course in most of these cases. There are very few such studies in the literature, none in radiology literature. We also describe some rare cases, including a case never described in any literature.     

A new hypothesis for sudden infant death syndrome: the occlusion of vertebral arteries as a major cause

Many factors, such as prematurity, low weight and minor infection, may predispose to Sudden Infant Death Syndrome (SIDS) but not cause it. It is suggested that the ultimate act of dying is due to the occlusion of one or both vertebral arteries triggered by the position of the head and cervical spine. When the head is turned to one side, the ipsilateral vertebral artery may be occluded at mid-cervical level along its length, or the contra lateral artery at atlanto-axial level or on both sides with the head in the initial position. Extension of cervical spine, with or without rotation, may produce obstruction of one or both vertebral arteries. If the degree, the levels and duration of occlusion are exceeded, particularly if there is a degree of failure of the collateral circulation (including one from carotid arteries via posterior communicating arteries), this can lead to prolonged apnoea, a 'near-miss' or cot death. The factors which may predispose to SIDS among others are hypoplasia or 'unexercised' vertebral arteries (in utero) and/or hypermobility of the immature cervical spine with lax joint capsules and ligaments. These factors allow the undue stretch or kinking of the vertebral arteries resulting in occlusion when the head or cervical spine are turned. The hypothesis explains the reduction of mortality of SIDS in infants in sleeping supine position to those in the prone position. In prone position, the infant's head is rotated 90 degrees which may put stress on atlas and axis thus occlude vertebral arteries by stretching and kinking. Infants under 6 months are unable to change position unaided so duration of obstruction is an aggravating element. These factors are about 50% less in the supine position.     

单节段颈椎间盘突出症前路减压术后上肢近端麻痹的研究

 目的 探讨单节段颈椎间盘突出症(cervical disc herniation ,CDH)行前路减压术后继发上肢近端麻痹(proximal upper limb palsy ,PULP)的发作特征及危险因素。方法 回顾性分析颈椎管前路减压分别联合融合或非融合固定术,治疗235例单节段CDH患者资料,术后随访时间均在12个月以上。术前PULP组和非PULP组一般资料比较,差异均无统计学意义。按照术前临床表现,分为以脊髓型和神经根型损害两组。减压节段包括C_3/4、C_4/5、C_5/6和C_6/7椎间隙。分别比较不同手术节段或术前定位体征亚组间术后PULP发生率。以C₅椎体为界,比较其上(下)椎间水平减压术后总体PULP发生率。结果 术后26例PULP患者均接受非手术治疗,末次随访均获得基本缓解。除C_4/5椎间隙和C₅髓节外,其余节段减压术后亦可继发PULP。C₅椎体上(下)各两个椎间减压术后PULP发生率和中下水平4个颈椎间隙减压术后PULP发生率比较,差异均无统计学意义。术前脊髓型表现者,术后PULP发生率高于神经根型表现者,差异有统计学意义。结论 术前为上运动神经元通路损害为主要表现者,CDH前路减压术后更易继发PULP。PULP发作应与固有束神经元体系的早期、可逆和暂时损害密切相关。     

Cervical spine injury in the very elderly

Background: Elderly patients are known to be at increased risk of cervical spine injuries. This propensity for injury becomes more important as the population of mobile elderly individuals increases. The present study seeks to examine the incidence and spectrum of spine injury among patients aged 80 years or greater, and to examine the efficacy of a decision rule for obtaining cervical spine radiography in this extreme age group. The decision rule would determine whether imaging could be avoided in patients who have none of the following: (1) posterior midline cervical spine tenderness; (2) focal neurological deficit; (3) abnormal level of alertness; (4) evidence of intoxication; or (5) clinically apparent distracting painful injury. Methods: All blunt trauma victims presenting to participating emergency departments underwent clinical evaluation prior to radiographic imaging. The elements of the decision rule were assessed and documented in each patient prior to radiographic imaging. The presence or absence of cervical spine injury was subsequently based on the final interpretation of all radiographic studies supplemented by a review of neurosurgical and risk management logs from each participating hospital. Data on all patients aged 80 years or greater were sequestered from the main database for separate analysis. Results: The study enrolled 34,069 individuals, including 818 patients (2.4 %) with cervical spine injuries. This population contained 1,070 patients (3.1 % of all cases) aged 80 or greater, 50 of whom (4.7 %) sustained cervical spine injuries. Injuries to the craniocervical junction (particularly C2 and the odontoid) accounted for 47.3 % of the injuries in the elderly, but only 28.6 % of injuries in younger patients. Older fracture victims were also likely to have more injuries (2.54 injuries/patient) than their younger counter parts (1.78 injuries/patient). The decision rule correctly identified all very elderly cervical spine injury victims [sensitivity 100.0 %; confidence interval (CI) 92.9–100.0 %], and designated 132 patients as “low-risk,” yielding a negative predictive value of 100.0 % (CI 97.3–100.0 %). Conclusions: The very elderly are at increased risked of cervical spine injury, particularly injury to the craniocervical junction. They also tend to have more extensive injuries than younger patients. Despite the increased risk of injury, the decision rule performed well in the very elderly, and allowed correct identification of all cervical spine injury victims.     

Flexion teardrop fracture of the cervical spine: radiographic characteristics

Teardrop fracture of the cervical spine is a confusing and loosely used term, often referring to any fracture with a triangular fragment in the involved body. The flexion teardrop fracture is a specific entity that should not be confused with other types of injury with a teardrop fragment. In a radiographic analysis of 45 patients with flexion teardrop fracture, the most characteristic feature was posterior displacement of the upper column of the divided cervical spine, observed in 78% of the cases. Other radiographic characteristics included backward displacement of the posterior fragment of the involved body, widening of the interlaminar and interspinous spaces, widening of the facet joint with backward displacement of the inferior facet, and kyphotic deformity of the cervical spine at the level of injury. The injury was frequently associated with sagittal-body and laminar fractures and occurred predominantly at the C5 level.     

Spinal cord injury without radiographic abnormalities in children and adolescents: case report of a severe cervical spine lesion and review of literature

The biomechanics of the child’s and juvenile’s spine is responsible for the commonly encountered closed spinal trauma with significant neurological injury but without bony or ligament injury (particularly of the cervical spine). The ¶ligamentous laxity and hypermobility of the young bony cervical and thoracic spine predispose to spinal cord injury without radiographic abnormalities. We report a 16-year-old ¶girl with typical features of this type of injury after a “flic-flac” sports ¶injury. We conclude that children ¶and adolescents who have neurological deficits without positive radiographic findings require appropriate diagnostic screening, monitoring, and often a prolonged therapy. ¶The sometimes changing neurological deficits should never be ¶ignored or dismissed as psychogenic affection.     

The value of retropharyngeal soft tissue measurements in trauma of the adult cervical spine

Widening of the retropharyngeal soft tissue space (RSTS) has been interpreted as a sign of cervical spine trauma. Widely differing measurements are reported in the literature. However it is clear that, using the currently acceptable limits of normal, a large number of patients without spinal injury are subjected to further tests. The RSTS on lateral cervical spine radiographs of 318 patients with a history of cervical spine trauma were measured at the C2–C4 level. The values for patients found to be normal or with fractures/dislocations were evaluated. Statistical analysis of the results demonstrates a considerable overlap in the RSTS of normal and abnormal patients. Therefore we suggest that RSTS measurements are of limited diagnostic value. Using the statistical probability of abnormality, guidelines that indicate which patients may require additional study are suggested.     

A single fracture in the ring of vertebrae below the atlas: report of four cases

A single fracture of the ring of a vertebra is a rare injury of the spine. In this report, we present five single fractures of the posterior ring of the cervical spine below the atlas from four patients after motor vehicle accidents. Initial radiographs failed to show any of these fractures; all were detected by computed tomography. Single ring fractures are stable and none of our patients presented with a neurological deficit. Patients were treated conservatively with a cervical collar or a cervicothoracic brace. They all recovered without any neurological abnormalities.     

C2–3 facet joint ”pseudo-fusion”: anatomic basis of a normal variant

 Objective. To identify the anatomic basis for apparent C2–3 facet joint fusion (pseudo-fusion) on lateral cervical spine radiographs. Design and patients. The studies of 81 consecutive blunt trauma patients who had both plain radiographs and a CT scan of the upper cervical spine were reviewed. The C2–3 facet joints were evaluated on lateral cervical spine radiographs and graded ”normal” (category 1), ”indistinct” (category 2), or ”fused” (category 3), relative to the C3–4 level. The accompanying CT scans were reviewed for the presence of fusion and the angle of orientation of the facet joints relative to the axial and coronal planes. Results. In category 1 (”normal”), the C2–3 facet joints were oriented nearly parallel to the true coronal and axial plane. In category 2 (”indistinct”), both the C2–3 facet joints were oriented obliquely to the true coronal and axial planes. In category 3 (”fused”), the C2–3 facet joints were also oriented obliquely, but at a steeper angle than in category 2. Head tilt/rotation caused a change in category rating in 5 of 81 cases (6.2%). Conclusion. The appearance of C2–3 facet joint fusion (pseudo-fusion) on lateral cervical spine radiographs may be a normal anatomic variant. This ”pseudo-fusion” is due to the oblique orientation of these facet joints relative to the X-ray beam and is usually unaffected by patient position.     

Vertebral artery injury and delayed midbrain infarction after unusual fracture of transverse foramen of C3 noted by bone scintigraphy

Vertebral artery dissection and thrombosis propagation causing neurologic sequelae is a rare complication of minor neck injury. Partial fracture of the transverse foramen of the third cervical vertebral body (C3) is uncommon. The authors report a case of vertebral artery injury and delayed midbrain infarction after an unusual fracture of only the upper half of the transverse foramen of C3, noted initially by bone scintigraphy. No other fracture was noted. A minor penetrating skin wound of the neck was not thought to be related to the fracture of the transverse foramen. The right lateral inferior edge of C2 was believed to have compressed the upper half of the transverse foramen of C3 by lateral hyperflexion. Innate laxity of the cervical spine at the level of C2 with respect to C3 in pediatric patients supports this belief.