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     

MR imaging of the alar ligament: morphologic changes during axial rotation of the head in asymptomatic young adults

OBJECTIVE:. The alar ligament plays a critical role in limiting the axial rotation of the head, the left alar ligament being stretched on rotation to the right and vice versa. The purposes of this study were to assess the usefulness of MR imaging in demonstrating the alar ligament and also to identify its morphologic changes during axial rotation of the head in asymptomatic young volunteers. DESIGN AND PATIENTS:. Twenty-two healthy volunteers participated in this study. All subjects underwent four series of contiguous fast spin echo density-weighted MR images with a 2 mm slice thickness including axial and coronal images with the head in neutral position, and coronal images with alternate head rotation to the right and left. The alar ligaments seen on each series of MR images were visually graded 0-2, and grade comparisons were performed between the four series of MR images. We also assessed the morphologic changes of the alar ligament on coronal images during axial rotation of the head. RESULTS:. Grade comparisons for the demonstration of the alar ligament revealed that each of three series of coronal images was statistically significantly better in grade than axial images. During axial rotation of the head, MR images showed rather constant morphologic changes of the alar ligament: elevation and wrapping of the contralateral alar ligament around the dens, associated with slightly upward movement of C1-C2 on that side. This wrap-around effect of the contralateral alar ligament in relation to the dens sometimes caused the apparent shortening of the alar ligament on that side. CONCLUSION:. Reliable assessment of the anatomy and function of the alar ligament can be achieved with MR imaging, preferably in coronal planes. MR imaging with the aid of a functional study may be a valuable imaging modality in the evaluation of alar ligament failure.     

翼状韧带的影像解剖学研究

目的探讨翼状韧带的位置、形态及走行，并深入研究其断面解剖形态及CT和MRI表现。方法采用经福尔马林固定的正常成人头颅标本12例，其中3例用于大体解剖观察，3例制成5．0mm厚的冰冻切片，6例制成0．5mm厚的薄层切片；选取2组各51例健康志愿者分别行CT和MRI检查。结合大体和断面解剖，分析翼状韧带的CT和MRI表现，并对其进行影像学测量。结果大体和断层解剖均能清晰显示翼状韧带的位置、形态及走行。齿状突上部的横断面和齿状突中部的冠状面是显示翼状韧带的理想层面。翼状韧带在CT和MRI横断面、冠状面及矢状面上的显示率均为100％（51／51）。对于翼状韧带结构的显示，MRI优于CT，尤其是质子密度加权成像的显示效果最佳。翼状韧带宽度在男女性别及左右侧别间的差异无统计学意义（P〉0．05）。结论CT和MRI均能较好地显示翼状韧带，结合大体和断层解剖进行研究，可为翼状韧带创伤、畸形及感染等病变的诊断提供影像解剖学支持。     

Association of diffuse idiopathic skeletal hyperostosis (DISH) and calcification and ossification of the posterior longitudinal ligament.

Diffuse idiopathic skeletal hyperostosis (DISH) is a common ossifying diathesis in middle-aged and elderly patients characterized by bone proliferation along the anterior aspect of the spine and at extraspinal sites of ligament and tendon attachment to bone. Four patients with DISH revealed extensive calcification and ossification of the posterior longitudinal ligament in the cervical spine. Review of cervical spine radiographs in 74 additional patients with DISH demonstrated bony hyperostosis of the posterior aspect of the vertebrae in 41%, posterior spinal osteophytosis in 34%, and posterior longitudinal ligament calcification and ossification in 50%. These ligamentous findings, which have previously been described almost exclusively in Japanese people, appear to be an additional skeletal manifestation of DISH.     

Heterotopic calcification and tears of the ulnar collateral ligament: radiographic and MR imaging findings

OBJECTIVE. The purpose of this paper is to describe the radiographic and MR imaging appearance of heterotopic calcification in the ulnar collateral ligament. MATERIALS AND METHODS. Retrospective radiographic review of 710 patients examined for elbow pain yielded 42 individuals (age range, 16-38 years) with heterotopic calcification in the ulnar collateral ligament. Radiographic and MR imaging findings were compared with surgical findings. RESULTS. Fifty-one heterotopic calcifications were identified in 42 patients; nine patients had two sites of heterotopic calcification. Average initial calcification size in the craniocaudal dimension was 4 mm (range, 1-12 mm) and in the transverse dimension was 1 mm (range, 1-4 mm). Five of 42 patients had enlargement of the calcification on follow-up radiography. The largest heterotopic calcification that was not visualized on MR imaging measured 5 x 4 mm in craniocaudal and transverse dimensions. Of 34 patients with heterotopic calcification who underwent surgery, 26 patients (76%) had either partial or complete tears of the ulnar collateral ligament. CONCLUSION. Heterotopic calcification in the ulnar collateral ligament may be associated with partial or complete tears. The MR imaging detection of heterotopic calcification is less sensitive than that of radiography of the elbow.     

MSCT对结节性甲状腺肿及甲状腺癌的鉴别诊断价值

目的 探讨MSCT对结节性甲状腺肿及甲状腺癌的鉴别诊断价值.方法 收集42例经手术及病理证实的甲状腺结节性病变患者的资料,其中结节性甲状腺肿30例,甲状腺癌12例,2例行平扫、40例行平扫及增强CT检查,用SPSS 17.0软件进行统计学处理.结果 病灶的数目和钙化有助于鉴别结节性甲状腺肿与甲状腺癌(P＜0.05),单发病灶及甲状腺沙砾钙化好发于甲状腺癌.而病变增强后密度是否均匀,边界是否规整,颈部是否有淋巴结肿大之间的比较无统计学意义(P＞0.05),但病变突破包膜及肿大淋巴结位于中央区有助于甲状腺癌的诊断.结论 MSCT有助于甲状腺癌与结节性甲状腺肿的鉴别诊断.     

CT、MRI对脊髓型颈椎病的诊断分析

目的探讨CT、MRI对脊髓型颈椎病（CSM）的诊断价值。方法对32例CSM患者的CT、MRI资料进行回顾性分析。结果 32例患者中,CT显示骨性椎管狭窄5例,其中先天性狭窄3例,椎体缘骨质增生22例,钩突和关节突关节增生20例,有不同程度椎间盘突出23例,后纵韧带及项韧带钙化13例。MRI显示椎间盘突出、变性28例,后纵韧带增厚21例,黄韧带增厚7例,全部病例脊髓不同程度受压,其中脊髓变性6例。结论 CT、MRI是重要的检查CSM的方法,能为临床治疗提供确切依据。     

Delayed diagnosis of isolated alar ligament rupture: A case report

Ligament disruptions at the craniovertebral junction are typically associated with atlantoaxial rotatory dislocation during upper cervical spine injuries and require external orthoses or surgical stabilization. Only in few patients isolated ruptures of the alar ligament have been reported. Here we present a further case, in which the diagnosis was initially obscured by a misleading clinical symptomatology but finally established six month following the trauma, demonstrating the value of contrast-enhanced high resolution 3 Tesla magnetic resonance imaging in identifying this particular lesion.     

Radiographic findings of degeneration in cervical spines of middle-aged soccer players

Twelve amateur veteran soccer players (average age 40.1±5.4 years), who began playing in their teens and who were admitted with symptoms most likely to be related to cervical spondylosis, were examined by cervical radiography. Abnormal radiographic findings included: calcification of anterior longitudinal ligament (25%), anterior (75%) and posterior vertebral spurs (75%), ossicle between spinous processes (75%), calcification of nuchal ligament (Barsony) (58%), ossicle on spinous process (25%), and bony spur of Luschka's joints (83%). It was shown in the stress distribution by finite element method analysis that the stress in heading the ball was applied mainly to the lower parts of the cervical spine. The results of this analysis also corresponded well with some of the radiographic findings.     

Myelopathy due to ossification or calcification of the ligamentum flavum: radiologic and histologic evaluations

The clinical, radiologic, and histologic features of ossification and calcification of the ligamentum flavum were studied in 18 patients. Ossification (15 patients) usually occurred in the lower thoracic spine in men of various ages, while calcification (three patients) was found exclusively in the cervical region of older women. Histologic examinations of ossification showed mature lamellar bone associated with proliferated cartilage replacing the ligamentum flavum (endochondral ossification). This corresponded well with radiographic and computed tomographic (CT) appearances. In the cases with calcification of the ligamentum flavum, calcification within the degenerated ligamentous fibers was observed on histologic examination, and correlated well with an oval nodular density on radiographs and CT. The two conditions differ in clinical, radiologic, and histologic considerations. Pathomechanisms in the development of these lesions and clinical significance are also discussed.     

甲状腺癌的CT诊断及误诊分析

目的分析甲状腺癌的CT表现，探讨CT在甲状腺癌的诊断价值及误诊原因。方法回顾性分析32例甲状腺癌患者术前CT资料及术后病理检查结果。结果32例中24例癌性病灶边缘不规则，10例为囊性伴高密度乳头状结节，9例出现钙化，13例侵犯周围组织器官，14例颈部淋巴结转移。术前误诊8例，误诊为腺瘤4例，结节性甲状腺肿3例，弥漫性甲状腺肿1例。结论肿瘤突破被膜向周围浸润，转移淋巴结内颗粒状钙化，肿物囊性变伴高密度乳头状结节是甲状腺癌的特征性表现；而肿瘤较小，边缘清晰或合并其他甲状腺疾病是误诊的主要原因。     

MRI of the alar and transverse ligaments in whiplash-associated disorders (WAD) grades 1–2: high-signal changes by age,gender, event and time since trauma

Introduction  This study describes the prevalence of high-signal changes at magnetic resonance imaging (MRI) of the alar and transverse ligaments in whiplash-associated disorders (WAD) grades 1–2 in relation to age, gender, spinal degeneration, type of trauma event and time since trauma. Materials and methods  In 1,266 consecutive WAD1–2 patients (779 women, 487 men; mean age 42 years) referred from clinicians, high-signal changes in the alar and transverse ligaments at high-resolution proton-weighted MRI were prospectively graded 0–3 based on a previously reported, reliable grading system. Type of event according to The International Statistical Classification of Diseases and Related Health Problems and time of trauma were obtained from referral letters. Results  MRI showed grades 2–3 alar ligament changes in 449 (35.5%; 95% confidence interval (CI), 32.8 to 38.1%) and grades 2–3 transverse ligament changes in 311 (24.6%; 95% CI, 22.2% to 26.9%) of the 1,266 patients. Grades 2–3 changes were more common in men than women, odds ratio 1.9 (95% CI, 1.5 to 2.5) for alar and 1.5 (95% CI, 1.1 to 2.0) for transverse ligament changes. High-signal changes were not related to age, spinal degeneration, type of trauma event or time since trauma (median 5 years). Unilateral changes were more often left- than right-sided. Conclusions  High-signal changes of the alar and transverse ligaments are common in WAD1-2 and unlikely to represent age-dependent degeneration. Their male and left-side preponderance cannot be explained by variation in ligament stretching or image artefacts. Further studies are needed to clarify whether such changes are caused by trauma.     

The crowned dens syndrome. Evaluation with CT imaging

PURPOSE: The purpose of this study was to verify the value of computed tomography (CT) in the diagnosis of the "crowned dens" syndrome, not only in crystal deposition diseases, but also in other rheumatic or nonrheumatic conditions. MATERIALS AND METHODS: Thirty-eight patients (15 men and 23 women; mean age 55 years; age range 35-79) with neck pain were examined and divided into two groups: (1) patients already identified as rheumatic and referred for further investigation of the atlantoaxial region; (2) patients with symptoms confined to the cervical spine, with inconclusive radiographic findings. Unenhanced CT of the cervical spine (Tomoscan SR 7000 Philips, Eindhoven, Netherlands) was performed in all patients. There were 11 cases of rheumatoid arthritis (ten women and one man), two calcium pyrophosphate dihydrate crystal deposition disease (both women), one of systemic sclerosis (a woman), one of osteoarthritis (a man), one of seronegative arthritis (a man), four of neoplasm (one woman and three men) with suspected cervical involvement, one (a man) of haematological disease (lymphoma), one (a woman) of menopausal osteoporosis, ten (five men and five women) of recent or previous trauma with suspected involvement of the skull base and first cervical vertebrae and six of unknown painful cervical dysfunction (three men and three women). RESULTS: CT demonstrated calcific deposits around the dens in 12 patients (three men and nine women), in the transverse and alar ligaments, and in the anterior atlantooccipital membrane. CT revealed horseshoe- or crown-like calcification surrounding the odontoid process. In our series, other rheumatic diseases, especially rheumatoid arthritis, showed similar irregular calcifications of the atlantoaxial joint. Discussion. In calcium pyrophosphate dihydrate (CPPD) crystal deposition disease, the spine may be the only site of involvement, generally asymptomatic. Crystals located in the transverse ligament of the atlas give rise to the crowned dens syndrome, usually in patients affected by severe degenerative lesions of the atlantoaxial joint and peripheral chondrocalcinosis. Symptoms may be absent, or a neurological compressive syndrome may develop. Symptoms tend to worsen with age. The diagnosis is not always easy, as the symptoms are similar to those of other diseases, such as meningitis, cervicobrachial pain, occipitotemporal headache, calcific tendinitis of the longus colli muscle, spondylodiscitis and retropharyngeal abscess. CONCLUSION: CT is the gold standard in identifying crowned dens syndrome, as it is able to depict the shape and site of calcification and any bone erosions. Radiography of other joints (wrist, knee, pubic symphysis) may help to ascertain whether the disease is due to calcium pyrophosphate dihydrate or hydroxyapatite crystals, and is therefore recommended for routine patient management. Magnetic resonance imaging (MRI) is indicated for the study of neurological complications.     

Computed tomography of the craniocervical junction in rheumatoid arthritis

Thirty-three patients with rheumatoid arthritis had computed tomographic examination of the craniocervical junction. This demonstrated soft tissue features which have not previously been described in published reports. A low attenuation lesion between the odontoid and the transverse ligament shown in 11 patients was considered a premonitory sign of rupture of the transverse ligament or a manifestation of active disease. Computed tomography revealed spinal cord compression in 3 patients and ligamentous changes in the transverse ligament and the alar and spinal ligaments in 26 patients. Erosion of the odontoid was shown in 19 patients and subluxation in 20 patients. No relationship could be found between the clinical signs and symptoms and the radiological abnormalities except in the case of cord compression.     

Calcinosis of the supraspinal ligament--a rare secondary finding

The supraspinal ligament calcification of thoracic spine is a rare roentgenographic finding. If this calcificated ligament is fractured several times it may be possible to misinterpret it as rib serial fractures, if it is overshadowed by dorsal ribs in the side projection of thorax. According to Resnick (4) such a ligamentous calcification is found within the overall framework of the "DISH"-syndrome.     

Fact or Fiction? MRI of Alar Ligaments and Craniocervical Junction Joints in Whiplash Syndrome

Abstract Whiplash injury of the cervical spine is a frequent issue in medical expertises and causes enormous consequential costs for motor insurance companies. Some authors accuse posttraumatic changes of alar ligaments to be causative of consequential disturbances, although biomechanical experiments achieve contradictory results and neuropsychiatric studies do not support this thesis. MRI provides excellent visualization of alar ligaments. However, signal alterations of alar ligaments must be differentiated from common normal variants. Functional MRI provides no diagnostic yield.      

螺旋CT扫描多平面重建（MPR）诊断颈椎退行性病变

目的 :探讨螺旋CT扫描并多平面重建 (MPR)对颈椎退行性病变的诊断价值。材料和方法 :对 45例颈椎病患者利用常规颈椎CT扫描和螺旋CT扫描并行MPR重建 ,对比分析扫描结果。结果 :螺旋CT扫描并MPR重建除显示 42例表现为一个以上椎间盘突出并压迫神经根及硬脊膜囊外 ,还显示椎体后缘骨质增生 3 0例 ,钩椎关节骨质增生 2 1例 ,2 3例共 2 7个椎间孔狭窄 ,12例共 15个横突孔狭窄 ,9个狭窄横突孔边缘骨质硬化增白 ,并可整体直观的观察韧带骨化、肥厚及椎管狭窄情况。结论 :螺旋CT扫描并MPR重建在显示颈椎退行性变各种病理改变方面比常规CT扫描具有重要的价值。     

甲状腺结节钙化与甲状腺癌的关系

 目的 探讨术前超声发现甲状腺结节钙化与甲状腺癌的关系。方法 回顾性分析武警总医院 2012 -06 至 2012 -08 行甲状腺结节手术的患者,术前超声检查的甲状腺结节钙化类型,以及和术中、术后病理结果之间关系。结果 58例中,良性病变31例,甲状腺乳头状癌27例。术前超声甲状腺结节钙化检出率39.7%,术后病理的钙化检出率为38%,术中冷冻的钙化检出率为17.2%。良性病变钙化检出率为16.1%,良性病变微钙化检出率6.4%;甲状腺乳头状癌钙化发生率66.7%,其中微钙化发生率为51.9%。良性病变与恶性病变之间的钙化发生率、微钙化发生率比较,差异均有统计学意义(P<0.01)。良性病变的单个结节钙化发生率为20%,恶性病变的单个结节钙化发生率为61.1%,两者比较差异有统计学意义(P<0.01)。结论 术前超声发现的甲状腺结节的微钙化与甲状腺癌的关系密切。     

Pitfalls of magnetic resonance imaging of alar ligament

An observational study of variations in the appearance of the alar ligament on magnetic resonance imaging (MRI) and the normal range of lateral flexion and rotation of the atlas was performed to validate some of the premises underlying the use of MRI for the detection of injuries to the alar ligament. Fifteen healthy volunteers were included. Three sets of coronal proton-density images, and axial T2-weighted images of the craniovertebral junction, were obtained at 0.5 T with the neck in neutral position and laterally flexed (coronal proton density) or rotated (axial T2). Five of the subjects also underwent imaging at 1.5 T. The scans were independently examined twice by two radiologists. The presence of alar ligaments was recorded and a three-point scale used to grade the extent of hyperintensity exhibited by the structures: the ligament were graded as 2 and 3 if, respectively, less or more of its cross-section was hyperintense, whereas grade 1 represented a hypointense ligament. The effect of lateral flexion on image quality was assessed. Concordance analysis of the data were performed before and after dichotomising the data on grading. The atlanto-axial angle and rotation of the atlas were measured. The magnitude of movement to right was normalised to that to the left to give, respectively, the flexion index and the rotation index. The alar ligaments were most reliably seen on coronal proton-density scans, with a Maxwells RE of 0.96 as compared with 0.46 for sagittal images. Flexion of the neck improved definition of the ligaments in only rare instances. Inter-observer disagreement was marked with respect to grading of the ligament on both coronal [composite proportion of agreement (p₀)=0.44; 95% confidence intervals: 0.26, 0.64)] and sagittal scans [p₀=0.40 (0.19, 0.63)]. Dichotomising the data did not appreciably improve reliability [Maxwells RE: –0.11 (coronal scans), –0.20 (sagittal scans)]: for ligaments which demonstrated hypertensive areas (grades 2 and 3) there was complete lack of agreement for both coronal [p₂=0 (0, 0.25)] and sagittal scans [p2=0 (0–0.30)]. A large response bias was found in the reports of both readers albeit in opposite directions. There was poor concordance between scans obtained at different field strengths [RE (coronal images)=0.25; RE (sagittal images)=0.14). Mean flexion index and mean rotation index were 1.00 (SD 0.03) and 1.01 (SD 0.06), respectively. The MR imaging may not be the investigation of choice for the investigation of subtle injuries to the alar ligament. Whether it can be substituted by kinematic assessment of the occipito-atlanto-axial complex with MRI warrants investigation.     

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.