Atlantoaxial osteoarthritis in rheumatoid arthritis: FDG PET/CT findings

The cervical spine is a common focus of destruction in patients with rheumatoid arthritis, and the resultant instability and neural compression represent severe complications in these patients. Evaluation of disease activity at the level of the atlantoaxial joint is important in such cases. Here, we report a 47-year-old man with a 3-year history of rheumatoid arthritis. FDG PET/CT clearly demonstrated a hot spot in the atlantoaxial area, suggesting high metabolic activity of synovitis.     

Prevalence of sternoclavicular joint calcium pyrophosphate dihydrate crystal deposition on computed tomography

We sought to determine the prevalence of sternoclavicular (SC) joint calcium pyrophosphate dihydrate (CPPD) crystal deposition and its association with age, osteoarthritis, and atlantoaxial CPPD crystal deposition. In 209 consecutive patients, computed tomographic examinations of the cervical spine were retrospectively reviewed. Overall prevalence of CPPD crystal deposition in the SC joint was 17.2% (36/209), which increased with age (P<.0001). There was also a significant association between SC CPPD and osteoarthritis (P=.024) as well as atlantoaxial joint CPPD crystal deposition (P=.006).     

Neurologic dysfunction in patients with rheumatoid arthritis of the cervical spine. Predictive value of clinical, radiographic and MR imaging parameters

The aim of this study was to evaluate if subjective symptoms, radiographic and especially MR parameters of cervical spine involvement, can predict neurologic dysfunction in patients with severe rheumatoid arthritis (RA). Sequential radiographs, MR imaging, and neurologic examination were performed yearly in 46 consecutive RA patients with symptoms indicative of cervical spine involvement. Radiographic parameters were erosions of the dens or intervertebral joints, disc-space narrowing, horizontal and vertical atlantoaxial subluxation, subluxations below C2, and the diameter of the spinal canal. The MR features evaluated were presence of dens and atlas erosion, brainstem compression, subarachnoid space encroachment, pannus around the dens, abnormal fat body caudal to the clivus, cervicomedullary angle, and distance of the dens to the line of McRae. Muscle weakness was associated with a tenfold increased risk of neurologic dysfunction. Radiographic parameters were not associated. On MR images atlas erosion and a decreased distance of the dens to the line of McRae showed a fivefold increased risk of neurologic dysfunction. Subarachnoid space encroachment was associated with a 12-fold increased risk. Rheumatoid arthritis patients with muscle weakness and subarachnoid space encroachment of the entire cervical spine have a highly increased risk of developing neurologic dysfunction. Received: 31 December 1999 Revised: 30 May 2000 Accepted: 5 June 2000     

The cervical spine in rheumatoid arthritis: relationship between neurologic signs and morphology on MR imaging and radiographs

 Objective. Comparison of clinically observed neurologic long tract signs in a heterogeneous group of patients with rheumatoid arthritis (RA), with morphologic abnormalities of the cervical spine as depicted on radiographs and magnetic resonance (MR) images. Design. The patients were prospectively assigned to one of three classes on the basis of their neurologic status. Lateral cervical spine radiographs and sagittal T1-weighted and gradient echo images were performed. The qualitative MR features evaluated were erosion of the dens and atlas, brain stem compression, subarachnoid space encroachment, pannus around the dens, appearance of the fat body caudal to the clivus, and the signal intensity of the pannus. The quantitative imaging parameters were the cervicomedullary angle and the distance of the dens to the line of McRae. Patients. Sixty-three consecutive patients with RA and subjective symptoms, especially neck or occipital pain, and/or clinical objective signs consistent with a compromised cervical cord were included in this study. Results and conclusions. Damage documented with radiographs and MR imaging in patients with RA is often severe, even in those without neurologic signs (class 1). None of the abnormalities confined to the atlantoaxial level correlated significantly with neurologic classification. Subarachnoid space encroachment anywhere in the entire cervical spine did correlate significantly with neurologic classification.     

Atlantoaxial instability associated with an orthotopic os odontoideum: a multimodality imaging assessment

Radiography, computed tomography (CT), and magnetic resonance imaging exams of the cervical spine were performed in a 29-year-old man who was ultimately diagnosed with an orthotopic os odontoideum during admission for injuries sustained in a motor vehicle collision. Initial radiography suggested either os odontoideum or an acute fracture of the dens. Further imaging with CT and flexion and extension radiographs confirmed os odontoideum and excluded a dens fracture. Although rare, os odontoideum is an important cervical spine anomaly to consider and to distinguish from an acute fracture of the dens.     

Imaging of tumoral calcinosis: new observations

Five patients with tumoral calcinosis were evaluated with radiography, bone scintigraphy, computed tomography (CT), and magnetic resonance (MR) imaging. The arthropathy of calcium pyrophosphate dihydrate deposition disease was seen in two of the patients and pseudoxanthoma elasticum-like syndrome in three. Identification of calcific particular masses on radiographs is characteristic of tumoral calcinosis. Marrow lesions could be identified as patchy areas of calcification (calcific myelitis) in long bones and the calvarium. Bone scintigraphy appears to be the best modality for detection of the masses and marrow lesions and for monitoring therapy. At CT the masses demonstrated a varied appearance, from small and solid to large and cystic. The marrow abnormality appears as an area of increased attenuation and spotty calcification that in the skull may be associated with dural and vascular calcifications. MR imaging of the particular masses was remarkable in that the masses displayed high signal intensity on T2-weighted images despite a large calcific component. Marrow lesions also showed increased signal intensity on T2-weighted images. When calcified particular masses are present the diagnosis is rarely in question. The diagnosis may be overlooked, however, when calcific myelitis is the only manifestation.     

The crowned dens syndrome: a rare form of calcium pyrophosphate deposition disease

The crowned dens syndrome has been termed as acute neck pain ascribed to CPPD deposits associated with a tomographic appearance of calcification surrounding the odontoid process. This rare entity resulting in cervical cord compression is generally seen in older female patients. We present a 26-year-old woman with cervical cord compression due to massive calcification in the periodontoid area and discuss the X-ray and CT findings of the disease. Received: 8 July 1999; Revised: 24 September 1999; Accepted: 12 November 1999     

CT analysis of the axis for transarticular screw fixation of rheumatoid atlantoaxial instability

Objective To investigate the morphological characteristics of the axis of rheumatoid arthritis (RA) patients with atlantoaxial instability and to determine, by means of sagittal reconstructed computed tomography (CT), the suitability for atlantoaxial transarticular screw fixation.Design and patients Twenty-seven patients, who had undergone reconstructed cervical spine CT scanning preoperatively and posterior atlantoaxial arthrodesis for atlantoaxial instability, were identified from a database for inclusion in this study. The isthmus height and internal height of the lateral mass of the axis were measured using digital imaging software.Results The mean isthmus height and internal height of the lateral mass of the axis in RA patients (n=14) were significantly lower than in non-RA patients (n=13) (P<0.01). A high-riding vertebral artery (VA) was present in 54% (15 joints, 9 patients) of the 28 atlantoaxial joints in the RA group and in 12% (3 joints, 2 patients) of the 26 atlantoaxial joints in the non-RA group (P<0.01).Conclusions In RA patients, the axis showed more extensive thinning of the isthmus and lateral mass than in non-RA patients. A precise preoperative evaluation of screw trajectory using reconstruction CT imaging may be useful in atlantoaxial transarticular fixation, particularly for RA patients with atlantoaxial instability.     

Cervical rheumatoid arthritis: value of flexion and extension views in imaging

The magnetic resonance (MR) imaging findings in the cervical spines of eight patients with long-standing polyarticular rheumatoid arthritis were reviewed. Three pathologic conditions were readily demonstrated: anterior atlantoaxial subluxation (n = 6), atlantoaxial impaction (n = 6), and subaxial subluxation (n = 6). An abnormal soft-tissue signal was noted in the preodontoid space in six patients; this signal was thought to represent the associated inflammatory mass. MR imaging was useful not only for depicting the bony abnormalities in the cervical spine that are associated with rheumatoid arthritis, but also can directly show the effect of the disease process on the spinal cord and brain stem.     

Calcium pyrophosphate dihydrate crystal deposition in and around the atlantoaxial joint: association with type 2 odontoid fractures in nine patients

PURPOSE: To investigate the histopathologic anatomy of calcium pyrophosphate dihydrate (CPPD) crystal deposition in and around the atlantoaxial joint and the association between CPPD crystal deposition and subchondral cysts, erosions, and fracture involving the odontoid process of the axis. MATERIALS AND METHODS: One adult cadaver demonstrating calcification in the retro-odontoid area at computed tomography (CT) was selected for further radiography, CT, and magnetic resonance (MR) imaging at the C1-2 level. Anatomic sectioning and histologic evaluations were performed in the specimen. For clinical study, radiographs (n = 5), CT scans (n = 8), and MR images (n = 6) in nine patients (mean age, 74.4 years) with odontoid process fractures and CPPD crystal deposits in and around the atlantoaxial joint were reviewed. RESULTS: In the cadaveric specimen, radiography and CT demonstrated calcifications in the transverse ligament; histologic evaluation confirmed that these calcifications were CPPD crystal deposits. In all nine patients, radiography (n = 5) and CT (n = 8) also showed calcification in areas adjacent to the odontoid process, which included the transverse ligament. T1- and T2-weighted MR imaging showed a retro-odontoid mass of low signal intensity that compressed the cervical cord in six patients. CT, MR imaging, or both demonstrated subchondral cysts, osseous erosions, or a type 2 odontoid fracture in all patients. CONCLUSION: CPPD crystal deposition disease involving the C1-C2 articulation can be a clinically important entity that may place affected patients at increased risk of pathologic fracture of the odontoid process.     

Significant new observations on cervical spine trauma.

The results of a computer analysis of 399 patients with documented fractures and/or dislocations of the cervical spine are summarized. Vertebral arch fractures were present in half of all patients with radiographic evidence of cervical spine trauma. Two-thirds of the patients had two or more injuries. Isolated disk injuries were rare and, when present, were characterized by a vacuum sign. The dens fracture, with or without atlantoaxial dislocation, was rarely associated with injury elsewhere in the cervical spine. The study suggests that the routine five-film cervical spine examination is inadequate to detect the most common traumatic lesions. Thus vertebral arch views (pillar views) should be obtained if there is evidence to suggest hyperextension as the mechanism of injury. In addition, the study underscores the importance of aggressively searching for multiple abnormalities.     

Laron syndrome abnormalities: spinal stenosis, os odontoideum, degenerative changes of the atlanto-odontoid joint, and small oropharynx

BACKGROUND AND PURPOSE: Patients with Laron syndrome have an inborn growth hormone resistance. We investigated abnormalities in the upper airways and cervical spine in patients with Laron syndrome. METHODS: We prospectively examined 11 patients (one child aged 9 years and 10 adults aged 36-68 years), 10 of whom underwent MR imaging of the spine or head; nine, radiography of the cervical spine; and four, CT of C1-C2. The width of the spinal canal was evaluated visually and quantitatively and compared with reference values. The smallest diameter of the oropharynx and the thickness of the palate were measured and compared with reference values. Nine age-matched female patients referred for MR imaging for unrelated reasons served as control subjects. RESULTS: Cervical spinal stenosis was present in seven of the adult patients, within a confidence interval of 95%. Anomaly of the dens compatible with os odontoideum was present in three patients, causing focal myelomalacia in two. The atlanto-odontoid joint showed osteoarthritic changes in six of the adult patients. The mediolateral diameter of the oropharynx was significantly smaller in the patients with Laron syndrome than in the control subjects (P <.005). There was no difference in the thickness of the soft palate. CONCLUSION: Patients with Laron syndrome develop significant narrowing of the cervical spinal canal and early degenerative changes of the atlanto-odontoid joint. Laron syndrome is associated with os odontoideum causing myelomalacia. The dimensions of the oropharynx are small. Patients may be prone to neurologic morbidity and sleep disturbances. Routine MR imaging of the cervical spine is recommended in these patients.     

经口咽前路寰枢椎复位钢板系统治疗陈旧性齿状突骨折

目的探讨经口咽前路寰枢椎复位钢板系统(transoralpharyngeal atlantoaxial reduction plate，TARP)在陈旧性齿状突骨折引起的寰枢椎脱位中的临床应用。方法对11例陈旧性齿状突骨折引起的寰枢椎脱位患者行经口咽前路松解减压，应用TARP系统复位和固定，两侧寰枢关节间植入自体髂骨融合。结果除1例因跌倒引起螺钉松动再次脱位外，均固定牢固，融合理想，脊髓减压满意。结论经口咽前路寰枢椎复位钢板系统一次完成寰枢椎脱位的复位和固定，是治疗陈旧性齿状突骨折造成的寰枢椎脱位以及其他原因引起的难复型寰枢椎脱位较为理想的手术方法。     

Upper cervical spine fracture: sources of misdiagnosis

PURPOSE: Missing cervical spine fractures during the initial plain film study may lead to severe neurological complications for patients and to medicolegal responsibilities for the physician. The upper cervical spine tract (C1-C2) is considered to be at high risk for misdiagnoses. We decided to investigate the possible causes of mistake in the cases of missed fractures on the initial plain film, performed in the emergency room. MATERIAL AND METHODS: We retrospectively reviewed the radiological reports, the original plain films and the CT findings, of 32 patients with upper cervical (C1-C2) fractures, admitted January 1994 to December 1998. Twenty-eight of these patients (87.5%) had multisystem trauma, 4 (12.5%) had minor craniocervical trauma. None of these patients had neurological signs correlated to the cervical injuries, 30 of them had normal consciousness and reported only neck pain, 2 of them were unconscious for the associated head trauma and were hospitalized in the intensive care unit. All the patients with normal consciousness underwent conventional three-view cervical spine radiography; the two unconscious patients in the intensive care unit were submitted to bedside examination with an anteroposterior and a lateral views of the cervical spine. All patients underwent spiral CT of the upper cervical tract. RESULTS: In 9 of 32 patients (28%) a cervical fracture was missed on the plain film and CT was performed only because of persistent neck pain. We found 2 Jefferson's fractures, 2 type II dens fractures, one type I dens fracture and 4 hangman's fractures. In 8 of the 9 patients (89%) the fracture was potentially unstable. Misdiagnoses resulted from overlapping bone structures (3%), suboptimal film quality (3%), satisfaction of search phenomenon (3%), missed mild tilting of the dens (6%), missed double cortex sign (16%), missed C1-C2 lateral subluxation (6%) and marked osteoporosis (3%). Prevertebral soft tissue swelling was not seen in any of the 9 cases of missed fractures. Considering the group of patients with C1-C2 fractures separately, the false negative rate is 28%, which corresponds to 10.7% of the total number of patients with cervical fractures and dislocations examined during the same period. CONCLUSIONS: Among the causes of false-negative interpretation, osteoporosis, suboptimal film quality due to associated fractures and overlapping bone structures must be considered unavoidable. On the other hand these possibilities should be indicated on the X-ray report because, if painful symptoms persist, a CT exam is strongly advised. Subtle alterations like dens tilting, double cortex sign, lateral subluxation of C1 and prevertebral soft tissue swelling should be regarded as highly suspicious for fracture. Missing these lesions might be considered a true diagnostic mistake with possible legal consequences, which may also expose the patient to the risk of neurological complications. The satisfaction of search phenomenon can be avoided only by trying to use a search pattern for every film, which includes checking all the visible anatomical structures even in the presence of a particularly evident lesion. In all questionable cases or high-risk fracture patients, even with an apparently negative plain film, it is advisable to perform CT instead of additional plain films. Finally, in all the patients treated in the intensive care unit for head trauma, an upper cervical CT scan should be routinely carried out at the same time as the brain scan.     

Changes at the base of skull and cervical spine in Down syndrome

Lateral films of the skull base and upper cervical spine in flexion, extension, and neutral positions in 165 patients with Down syndrome, ranging in age from 16 to 60 years, were analyzed. There is a 20% incidence of atlantoaxial subluxation with a marked preponderance in men (24% incidence compared to 15% in women). In addition, there is a high incidence of degenerative changes at the C2-3 and C3-4 cervical interspaces, especially in patients over 37 years of age; these are unusual sites when compared to the normal population in which the degenerative changes are most often at the C5-6 and C6-7 levels. Four patients demonstrated subluxation at cervical interspaces other than C1-2 and six had congenital fusion of either vertebral bodies or facets in the cervical region. Several patients also had flattening of cervical vertebrae; 20% of patients had nonaeration of the sphenoid sinus and 46% had partial aeration.     

唐氏综合征患儿寰枢椎不稳定颈后路内固定术的疗效

 目的 探讨唐氏综合征(Down's syndrome, DS)患儿寰枢椎不稳定(atlantoaxial instability, AAI)行颈后路内固定手术的疗效。方法 选择2012-06至2018-11北京儿童医院收治的DS伴AAI患儿12例,其中男5例,女7例,年龄3~14岁,平均(6.9±3.1)岁。术前均行颈椎正侧位+前屈后伸位X线片并行颈椎CT平扫+重建了解椎体、C₁侧块、C₂椎弓根发育情况及椎动脉(VA)情况,有脊髓受压表现的患儿进一步完善颈椎MR检查。术后定期随访复查颈椎正侧位及前屈后伸位X线片,行颈椎CT平扫+重建了解寰枢椎对位、植骨融合及内固定情况,测量并记录术前、术后及末次随访时的寰齿前间距(atlas-dens interval, ADI)及脊髓有效空间(space available for the spinal cord, SAC)数值。结果 术后随访1.6~4.9年,平均(2.6±1.2)年。10例行C₁侧块螺钉及C₂椎弓根螺钉固定,2例用枕骨板连接C_1、2螺钉行枕-颈固定融合。ADI由术前的(7.0±2.1)mm减小到末次随访时的(1.4±0.8)mm(P<0.01),SAC由术前的(13.6±5.2)mm增加到末次随访时的(19.0±3.0)mm(P<0.01)。术后第3及6个月定期行颈部CT检查,至末次随访时所有患儿均获得了良好的骨性融合。结论 对DS患儿伴AAI行后路C₁、C₂螺钉固定及枕骨板等内固定可达到良好的治疗效果。     

Evaluation of flexion/extension of the upper cervical spine in patients with rheumatoid arthritis: an MRI study with a dedicated positioning device compared to conventional radiographs

PURPOSE: Using flexion/extension magnetic resonance imaging (MRI) with a dedicated positioning device, our purpose was to analyze pathologic cranio-vertebral joint anatomy and motion in patients with rheumatoid arthritis in comparison to normal patients, and to compare flexion/extension MRI with conventional radiographs (CRs) in patients with rheumatoid arthritis. MATERIAL AND METHODS: The 31 patients with rheumatoid arthritis and 20 healthy subjects included in the study were imaged in an open MRI scanner during flexion/extension. A dedicated positioning device was used. Additionally, we compared flexion/extension MRI with CRs in patients with rheumatoid arthritis. In MRI, the orientation and segmental motion of C0, C1, and C2 were assessed and structure of the dens and amount of pannus tissue were observed. Configuration of the cerebrospinal fluid space and the cord was evaluated in each position. In both MRI and CRs, anterior atlanto-axial subluxation and vertical dislocation were assessed and sagittal diameter of the dural sac was measured. RESULTS: In the neutral position, C1 of the patients was oriented in a more flexed position in relation to both C0 and C2 compared to that in healthy subjects. The patients had more extension in the upper cervical spine than did healthy subjects. In flexion, atlantoaxial subluxation was greater in CRs than in MRI. In MRI, the amount of vertical dislocation did not depend on position. In the patients, there was considerably more cord impingement in flexion than in other positions. CONCLUSION: Evaluation of the rheumatoid cervical spine is optimized using MR images in the neutral, flexed, and extended positions. Measurements and relationships between structures should be compared in all positions. CRs with flexion-extension views are recommended as the first imaging method.     

Rheumatoid arthritis and pseudo-rheumatoid arthritis in calcium pyrophosphate dihydrate crystal deposition disease

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease can lead to many clinical syndromes. One syndrome simulates rheumatoid arthritis and is thus called "pseudo-rheumatoid arthritis." Since some patients have true rheumatoid arthritis with CPPD crystal deposition disease, the clinician may have difficulty differentiating those patients from others who have the pseudo-rheumatoid syndrome. Such a diagnostic problem can be solved radiographically. Eleven patients with CPPD crystal deposition disease were studied; five had true rheumatoid arthritis and six had pseudo-rheumatoid arthritis. Because osseous erosions were not apparent in the arthropathy of uncomplicated CPPD crystal deposition disease, the detection of skeletal erosive changes indicated a true rheumatoid arthritis process.     

MR imaging of atlantoaxial joint in early rheumatoid arthritis

Purpose

This study was done to assess the involvement of the atlantoaxial joint in patients with early rheumatoid arthritis and evaluate the role of magnetic resonance (MR) imaging in depicting this early joint involvement.

Materials and methods

Twenty patients (16 women and four men, mean age 55.0±12.9 years) with clinical and laboratory evidence of early rheumatoid arthritis (mean disease duration <12 months) were included in our study. MR imaging of the atlantoaxial joint was performed in all patients within 3 months from diagnosis. The MR features were correlated with clinical and biochemical variables.

Results

Five (25.0%) of the 20 patients exhibited enhancement of the periodontoid synovial spaces after gadolinium administration due to inflammatory synovitis. Compared with patients without cervical involvement, these five patients showed significantly higher values of erythrocyte sedimentation rate [median 77.0 mm/h (range 25th and 75th percentile 69.0–86.0) vs median 33.0 mm/h (range 25th and 75th percentile: 9.2–52) (p=0.007)]; significantly higher C-reactive protein values [median 53.6 mg/l (range 25th and 75th percentile 21.9–81.9) vs median 14.0 mg/l (range 25th and 75th percentile 0.8–20) (p=0.03)]; higher disease activity score [median 4.2 (range 25th and 75th percentile 3.9–5.4) vs median 3.2 (range 25th and 75th percentile 2.8–3.8) (p=0.03)]. Four (80%) of these five patients presented anti-citrulline antibodies (anti-CCP) and rheumatoid factor at laboratory testing. The latter was positive in 12 of the 20 patients (66%), and anti-CCP were positive in 15 (83%).

Conclusions

MR imaging showed an atlantoaxial inflammatory synovitis in 25% of patients with early rheumatoid arthritis. Our results indicate that patients with higher disease activity are likely to be at higher risk of presenting early involvement of the atlantoaxial joint. MR imaging of the cervical spine is an excellent tool for assessing the early manifestations of rheumatoid arthritis before any destructive changes occur. Therefore, MR imaging should be included in the diagnostic workup in order to provide reliable guidance for treatment choices.     

MRI of the cervical spine: rheumatoid arthritis compared with cervical spondylosis

This study is a comparison of the cervical spine MR images from 26 patients with rheumatoid arthritis of the cervical spine with those from an age and sex matched group suffering from cervical spondylosis. Erosion of bone and major atlanto-axial subluxation were confined to rheumatoid arthritis. Soft tissue changes revealed by MRI included distortion of normal ligaments and bursae around the dens, particularly in rheumatoid arthritis. Abnormal masses of soft tissue were found in both groups, but those suggesting acute inflammation were much more frequent in rheumatoid arthritis than in cervical spondylosis. Neural compression was well demonstrated, and in rheumatoid arthritis was usually caused by bony structures whereas in cervical spondylosis it was usually due to disc material. It is concluded that MRI should be used as the first investigation to follow plain films in rheumatoid arthritis of the cervical spine. Bone and soft tissue changes are clearly shown, but interpretation of the images requires the recognition that some observed abnormalities may be due to coincidental cervical spondylosis.