Natural history of rheumatoid arthritis of the cervical spine

Prevalence and location of inflammatory and structural lesions in patients with rheumatoid arthritis and radiographic axial spondyloarthritis with chronic neck pain evaluated by magnetic resonance imaging

OBJECTIVE

Define the prevalence and location of inflammatory and structural lesions on magnetic resonance imaging (MRI) in patients with rheumatoid arthritis (RA) and radiographic axial spondyloarthritis (r-axSpA) with neck pain as leading clinical symptom.

METHODS

Patients with diagnosis of RA and r-axSpA were consecutively included if they had chronic (> 3 months) neck pain. Clinical assessment, neck pain questionnaires and MRIs of the cervical spine (CS) were performed.

RESULTS

107 patients (59 RA and 48 r-axSpA) were included. While there was no difference in the Northwick-Park-Neck-Pain-questionnaire, patients with RA reported higher neck pain compared to r-axSpA on a numeric rating scale (5.0 ± 3.6 vs. 3.0 ± 3.1; p = 0.003). Inflammatory lesions occurred predominantly in the craniocervical area in RA and in the lower CS segments in r-axSpA. Bone marrow edema (BME) was more frequent in axSpA (BME-score axSpA/RA: 0.35vs0.17; p < 0.001) while synovitis was visible in both but was more prevalent in RA (synovitis-score axSpA/RA: 0.02vs0.1; p < 0.001). BME was found in 8 (13.6%) vertebral corner vs. 9 (18.8%), in 2 (3.4%) facet joints vs. 7 (14.6%) and in 1 (1.7%) spinous processes vs. 9 (18.8%) in patients with RA/r-axSpA. In contrast, more patients with RA (30.5% vs6.3%) showed erosive osteochondrosis with endplate BME (p = 0.002).

CONCLUSION

While involvement of upper cervical inflammation was typically present in RA, r-axSpA patients showed more BME in lower CS segments, vertebral corners, facet joints and spinous processes. Neck pain is linked to upper and lower inflammatory and structural lesions of the CS in both diseases.

Automatic evaluation of atlantoaxial subluxation in rheumatoid arthritis by a deep learning model

BACKGROUND

This work aims to develop a deep learning model, assessing atlantoaxial subluxation (AAS) in rheumatoid arthritis (RA), which can often be ambiguous in clinical practice.

METHODS

We collected 4691 X-ray images of the cervical spine of the 906 patients with RA. Among these images, 3480 were used for training the deep learning model, 803 were used for validating the model during the training process, and the remaining 408 were used for testing the performance of the trained model. The two-dimensional key points' detection model of Deep High-Resolution Representation Learning for Human Pose Estimation was adopted as the base convolutional neural network model. The model inferred four coordinates to calculate the atlantodental interval (ADI) and space available for the spinal cord (SAC). Finally, these values were compared with those by clinicians to evaluate the performance of the model.

RESULTS

Among the 408 cervical images for testing the performance, the trained model correctly identified the four coordinates in 99.5% of the dataset. The values of ADI and SAC were positively correlated among the model and two clinicians. The sensitivity of AAS diagnosis with ADI or SAC by the model was 0.86 and 0.97 respectively. The specificity of that was 0.57 and 0.5 respectively.

CONCLUSIONS

We present the development of a deep learning model for the evaluation of cervical lesions of patients with RA. The model was demonstrably shown to be useful for quantitative evaluation.

Epidemiology of neuropathic pain: an analysis of prevalence and associated factors in UK Biobank

Supplemental Digital Content is Available in the Text.

An analysis of UK Biobank participants who completed a detailed pain questionnaire identified factors associated with neuropathic pain (NeuP) vs no chronic pain and non-NeuP and estimated the prevalence of NeuP.

Introduction:

Previous epidemiological studies of neuropathic pain have reported a range of prevalences and factors associated with the disorder.

Objectives:

This study aimed to verify these characteristics in a large UK cohort.

Methods:

A cross-sectional analysis was conducted of 148,828 UK Biobank participants who completed a detailed questionnaire on chronic pain. The Douleur Neuropathique en Quatre Questions (DN4) was used to distinguish between neuropathic pain (NeuP) and non-neuropathic pain (non-NeuP) in participants with pain of at least 3 months' duration. Participants were also identified with less than 3 months' pain or without pain (NoCP). Multivariable regression was used to identify factors associated with NeuP compared with non-NeuP and NoCP, respectively.

Results:

Chronic pain was present in 76,095 participants (51.1%). The overall prevalence of NeuP was 9.2%. Neuropathic pain was significantly associated with worse health-related quality of life, having a manual or personal service type occupation, and younger age compared with NoCP. As expected, NeuP was associated with diabetes and neuropathy, but also other pains (pelvic, postsurgical, and migraine) and musculoskeletal disorders (rheumatoid arthritis, osteoarthritis, and fibromyalgia). In addition, NeuP was associated with pain in the limbs and greater pain intensity and higher body mass index compared with non-NeuP. Female sex was associated with NeuP when compared with NoCP, whereas male sex was associated with NeuP when compared with non-NeuP.

Conclusion:

This is the largest epidemiological study of neuropathic pain to date. The results confirm that the disorder is common in a population of middle- to older-aged people with mixed aetiologies and is associated with a higher health impact than non-neuropathic pain.

Radiological assessment and surgical management of cervical spine involvement in patients with rheumatoid arthritis

The purpose of the present systematic review was to describe the diagnostic evaluation of rheumatoid arthritis in the cervical spine to provide a better understanding of the indications and options of surgical intervention. We performed a literature review of Pub-med, Embase, and Scopus database. Upon implementing specific inclusion and exclusion criteria, all eligible articles were identified. A total of 1878 patients with Rheumatoid Arthritis (RA) were evaluated for cervical spine involvement with plain radiographs. Atlantoaxial subluxation (AAS) ranged from 16.4 to 95.7% in plain radiographs while sub-axial subluxation ranged from 10 to 43.6% of cases. Anterior atlantodental interval (AADI) was found to between 2.5 mm and 4.61 mm in neutral and flexion position respectively, while Posterior Atlantodental Interval (PADI) was between 20.4 and 24.92 mm. 660 patients with RA had undergone an MRI. A pannus diagnosis ranged from 13.33 to 85.36% while spinal cord compression was reported in 0-13% of cases. When it comes to surgical outcomes, Atlanto-axial joint (AAJ) fusion success rates ranged from 45.16 to 100% of cases. Furthermore, the incidence of postoperative subluxation ranged from 0 to 77.7%. With regards to AADI it is evident that its value decreased in all studies. Furthermore, an improvement in Ranawat classification was variable between studies with a report improvement frequency by at least one class ranging from 0 to 54.5%. In conclusion, through careful radiographic and clinical evaluation, cervical spine involvement in patients with RA can be detected. Surgery is a valuable option for these patients and can lead to improvement in their symptoms.

Rheumatoid Diseases Involving the Cervical Spine I. History, Definition, and Diagnosis: New Trends and Technologies

The cervical spine might be involved in several conditions: congenital, traumatic, and chronic inflammatory and or degenerative rheumatic disorders. Among the inflammatory rheumatic conditions that can affect the cervical spine, rheumatoid arthritis (RA) is the most common, affecting up to 86% of patients and leading to cervical spine instability and subsequent myelopathy. Other inflammatory diseases include juvenile idiopathic arthritis (JIA) and the spondyloarthritis group (SpA), including psoriatic arthritis. Since many patients do not show symptoms of cervical involvement, diagnosis is often delayed. Radiographs are the first line imaging modality used to detect such involvement, but MRI and CT are superior in terms of early diagnosis and surgical planning.In this review, we provide an overview of cervical involvement in RA, JIA, and SpA.

Update on imaging of the cervical spine in rheumatoid arthritis

Rheumatoid arthritis is a multisystem, autoimmune, inflammatory disorder with numerous musculoskeletal manifestations. Involvement of the cervical spine is common and may result in severe complications due to synovitis, erosions, pannus formation, spinal instability and ankylosis. The purpose of this article is to review the current role of imaging in the rheumatoid spine, with emphasis on radiographs and MRI.

Recurrent Cervical Subdural Bleeding Because of Atlantoaxial Instability in a Patient with Rheumatoid Arthritis: A Case Report

CASE

Atlantoaxial instability (AAI) is a frequent complication of rheumatoid arthritis (RA), but its involvement in intracranial bleeding is unclear. We present a young woman with history of systemic lupus erythematosus and RA who developed 3 episodes of subdural bleeding at the upper cervical spine and cranial level. Imaging tests showed signs of AAI with odontoid deformity. The case was interpreted as recurrent traumatic cervical subdural hemorrhage because of AAI. No new episodes occurred after surgical C1-C2 fixation.

CONCLUSION

We report a case that had the association of hemorrhage and C1-2 instability in a patient with RA and lupus erythematosus.

Risk factor analysis of perioperative complications in patients with rheumatoid arthritis undergoing primary cervical spine surgery

Background

Rheumatoid arthritis (RA) often causes cervical spine lesions as the disease condition progresses, which induce occipital neuralgia or cervical myelopathy requiring surgical interventions. Meanwhile, patients with RA are susceptible to infection or other complications in the perioperative period because they frequently have comorbidities and use immunosuppressive medications. However, the risk factors or characteristics of patients with RA who experience perioperative complications after cervical spine surgery remain unknown. A risk factor analysis of perioperative complications in patients with RA who underwent primary cervical spine surgery was conducted in the present study.

Methods

A total of 139 patients with RA who underwent primary cervical spine surgery from January 2001 to March 2020 were retrospectively investigated. Age and height, weight, serum albumin, serum C-reactive protein, American Society of Anesthesiologists Physical Status (ASA-PS), Charlson comorbidity index, medications used, cervical spine lesion, surgery time, bleeding volume, and procedures were collected from medical records to compare the patients with complications to those without complications after surgery. The risk factors for perioperative complications were assessed by univariate and multivariate logistic regression analysis.

Results

Twenty-eight patients (20.1%) had perioperative complications. Perioperative complications were significantly associated with the following factors [data presented as odds ratio]: lower height [0.928, p=0.007], higher ASA-PS [2.296, p=0.048], longer operation time [1.013, p=0.003], more bleeding volume [1.004, p=0.04], higher rates of vertical subluxation [2.914, p=0.015] and subaxial subluxation (SAS) [2.507, p=0.036], occipito-cervical (OC) fusion [3.438, p=0.023], and occipito-cervical/thoracic (long) fusion [8.021, p=0.002] in univariate analyses. In multivariate analyses, lower height [0.915, p=0.005], higher ASA-PS [2.622, p=0.045] and long fusion [7.289, p=0.008] remained risk factors. High-dose prednisolone use [1.247, p=0.028], SAS [6.413, p=0.018], OC fusion [17.93, p=0.034], and long fusion [108.1, p<0.001] were associated with severe complications.

Conclusions

ASA-PS and long fusion could be indicators predicting perioperative complications in patients with RA after cervical spine surgery. In addition, cervical spine lesions requiring OC fusion or long fusion and high-dose prednisolone use were suggested to be risk factors for increasing severe complications.

Radiological and clinical comparisons of the patients with rheumatoid arthritis operated with rigid and dynamic instrumentation systems due to lumbar degenerative spinal diseases

BACKGROUND

It is extremely difficult to treat spine disorders with stabilization in patients with rheumatoid arthritis. Because revision rates are significantly higher in rigid stabilization. To date, there is no data about patients with rheumatoid arthritis treated with dynamic stabilization. Our aim was to compare the radiological and clinical results of patients with rheumatoid arthritis who underwent lumbar rigid stabilization or dynamic stabilization with Polyetheretherketone rod (PEEK).

METHODS

Patients with degenerative lumbar spine disease with rheumatoid arthritis who underwent dynamic stabilization between 2013 and 2015 and rigid stabilization between 2010 and 2012 were evaluated radiologically for adjacent segment disease, proximal junctional kyphosis, system problem (nonunion, screw loosening, instrumentation failure, pull out). It was also compared according to both the revision rates and the Visual Analog Scale and Oswestry Disability Index scores at the 12th month and 24th month.

RESULTS

The difference of decrease in Visual Analog Scale and Oswestry Disability Index scores from preoperative to 12th month between patients who underwent dynamic stabilization and rigid stabilization was statistically insignificant. However, there was a significant difference of increase in Visual Analog Scale and Oswestry Disability Index scores between the 12th month and 24th month of patients who underwent rigid stabilization, compared with patients with dynamic stabilization. In patients with dynamic stabilization, the problems of instrumentation were seen less frequently. Revision rates were high in patients with rigid stabilization when compared the patients with dynamic stabilization.

CONCLUSION

Radiological and clinical outcomes in patients with rheumatoid arthritis operated with dynamic stabilization are more significant when compared to rigid stabilization. These patients have lower pain and disability scores in their follow up periods. Revision rates are lower in patients with dynamic stabilization.

Cervical spine manifestations of rheumatoid arthritis: a review

Rheumatoid arthritis (RA) is a progressive autoimmune inflammatory disease affecting 1% of the population with three times as many women as men. As many as 86% of patients suffering from RA have cervical spine involvement. Synovial inflammation in the cervical spine causes instability and injuries including atlantoaxial subluxation, retroodontoid pannus formation, cranial settling, and subaxial subluxation. While many patients with cervical spine involvement are asymptomatic, symptomatic patients often present with nonspecific symptoms resulting from inflammation and additional secondary symptoms that are due to compression of the brainstem, cranial nerves, vertebral artery, and spinal cord. Radiographs are the imaging modality used most often, while MRI and CT are used for assessment of neural element involvement and surgical planning. Multiple classification systems exist. Early diagnosis and treatment of cervical spine involvement is critical. Surgical management is indicated when patients experience symptoms from cervical involvement that result in biomechanical instability and, or a neurological deficit. Atlantoaxial instability managed with atlantoaxial fusion, retroodontoid pannus with neural element compression is managed with posterior decompression and atlantoaxial fusion or occipitocervical fusion. Cranial settling is managed can be managed with anterior decompression and posterior fusion or with dorsal only approaches. Subaxial subluxation is managed with circumferential fusion or posterior only decompression and fusion. Patients with atlantoaxial instability have better functional and neurologic outcomes. RA patients have higher complication rates and more frequent need for revision surgery than the general population of spine surgery patients.

Technical outcome of atlantoaxial transarticular screw fixation without supplementary posterior construct for rheumatoid arthritis

Background

transarticular screw (TAS) fixation without a supplementary posterior construct, even in rheumatoid arthritis (RA) patients, provides sufficient stability with acceptable clinical results. Here, we present our experience with 15 RA patients who underwent atlantoaxial (AA) TAS fixation without utilizing a supplementary posterior fusion.

Methods

To treat AA instability, all 15 RA patients underwent C1-C2 TAS fixation without a supplementary posterior construct. Patients were followed for at least 24 months. Pre- and postoperative sagittal measures of C1- C2, C2-C7, and C1-C7 angles, atlanto-dens interval (ADI), posterior atlanto-dens interval (PADI), and adjacent segment (i.e., C2-C3) anterior disc height (ADH) were retrospectively recorded from lateral X-ray imaging. The presence or absence of superior migration of the odontoid (SMO), cervical subaxial subluxation, C1-C2 bony fusion, screw pull-out, and screw breakage were also noted.

Results

There was little difference between the pre- and postoperative studies regarding angles measured. Following TAS fixation, the mean ADI shortened, and mean PADI lengthened. There was no difference in the mean measures of C2-C3 ADH. There was no evidence of SMO pre- or postoperatively. Two patients developed anterior subluxation at C5-C6; one of the two also developed anterior subluxation at C2-C3. All patients subsequently showed C1-C2 bony fusion without screw pull-out or breakage.

Conclusion

In RA patients who have undergone C1-C2 TAS fixation, eliminating a supplementary posterior fusion resulted in adequate stability.

Early Report on the Impact of COVID-19 Outbreak in Neurosurgical Practice Among Members of the Latin American Federation of Neurosurgical Societies

BACKGROUND

The COVID-19 pandemic has caused severe economic consequences by local governmental measures to contain the outbreak. We provide insight on the impact that health care restriction has made on neurosurgical activity in Latin Iberoamerica.

METHODS

We performed an internet-based survey among presidents and members of the societies of the Latin American Federation of Neurosurgical Societies (FLANC). We blindly analyzed information regarding local conditions and their impact on neurosurgical praxis using SPSS software.

RESULTS

Information came from 21 countries. Sixteen society presidents reported having suspended regular activities and deferring local scheduled congresses, 14 reported mandatory isolation by government, and 4 instituted a telemedicine project. Four-hundred eighty-six colleagues, mean age 49 years, reported a mean 79% reduction in their neurosurgical praxis. Seventy-six percent of neurosurgeons have savings to self-support for 3-6 months if restrictions are long lasting.

CONCLUSIONS

Stopping activities among societies of the FLANC, together with a drop of 79% of neurosurgical praxis, adds to deficits in provider's protection equipment and increasing demand for attention in the health care systems, representing a huge financial risk to their sustainability. Neurosurgeons should be involved in local policies to protect health and economy. Telemedicine represents an excellent solution, avoiding another pandemic of severe diseases across all-specialties as nonessential care can turn essential if left untreated. Financial support and ethics code review is needed to battle this new disease, designated the occupational disease of the decade, that continues to scrag the health care system. Times of crisis are times of great opportunities for humanity to evolve.

Morphological classification of the tubercle of insertion of the transverse atlantal ligament: A computer tomography-based anatomical study of 200 subjects

BACKGROUND AND PURPOSE

The atlantal tubercle is the attachment point of the transverse atlantal ligament, the main stabilizer of the atlantoaxial complex. No system of classification of the tubercle exists in the literature. We aimed to develop a morphologically based classification system of the atlantal tubercle to aid clinicians who deal with craniocervical pathology.

MATERIALS AND METHODS

A retrospective review of computed tomography (CT) scans of the cervical spine was performed. The morphology of the atlantal tubercle was classified into four variants: rounded (classical), pointed, flattened, and hypoplastic. Age, presence, and morphological type were recorded.

RESULTS

A total of 200 CT scans were identified and reviewed. The tubercle was present bilaterally in all patients. Patients were equally distributed over various age ranges. The following morphological types were recorded: rounded (227/400; 56.8%), pointed (13/400; 3.3%), flattened (126; 31.5%), and hypoplastic (34/400; 8.5%). The same type was seen bilaterally in 68% (135/200) of patients. Morphological types appear equally on the right and left side of the atlas.

CONCLUSIONS

The first morphologically based classification system of the atlantal tubercle utilizing CT is presented. Morphology type, especially hypoplastic type, may confer an increased risk for subsequent need for posterior fusion.

Magnetic resonance imaging of the craniovertebral junction in early rheumatoid arthritis

OBJECTIVE

To assess the involvement of the atlantoaxial joint in patients with early rheumatoid arthritis (ERA) and to elucidate the risk profile for the individual patient.

MATERIALS AND METHODS

Consecutive ERA patients (disease duration < 12 months) were included in our study. A cervical spine magnetic resonance imaging (MRI) and X-rays (cervical spine, hands, wrists, and feet) were performed in all patients. The MRI features were correlated with clinical, radiological, and biochemical variables.

RESULTS

Fifty patients (13 men and 37 women) with a mean age of 58.2 years (range, 36-79 years) were included in the study. In 12 (24%) patients were detectable MRI findings suggestive of the craniovertebral junction involvement. Compared with patients without cervical involvement, the patients with atlantoaxial synovitis showed a significantly higher anti-citrullinated protein antibodies (ACPA) titer [mean 200.25 UI (SD 262.44) vs. mean 22.05 (SD 40.21) (p < 0.001)]; a worse Disease Activity Score 44 joints (DAS44) [mean 5.72 (SD 0.44) vs. mean 4.52 (SD 0.53) (p < 0.001)]; a worse Health Assessment Questionnaire Disability Index (HAQ-DI) [mean 1.55 (SD 0.37) vs. mean 1.09 (SD 0.33) (p < 0.001)], and a higher Simple Erosion Narrowing Score (SENS) [mean 15.83 (SD 4.52) vs. mean 7.71 (SD 3.43) (p < 0.001)]. The multivariate analysis revealed a meaningful relationship between atlantoaxial synovitis and ACPA, DAS44, and the presence of an erosive disease.

CONCLUSIONS

The craniovertebral junction is frequently involved in ERA patients. ACPA, high disease activity, and erosive disease at baseline are predictors of atlantoaxial involvement.

Can neck pain be an initial symptom of rheumatoid arthritis? A case report and literature review

Although rheumatoid arthritis (RA) is most commonly associated with peripheral joints, cervical spine involvement can be seen in almost 80% of patients in the presence of long-term disease, joint erosion, and risk factors such as male sex and rheumatoid factor positivity. It is very rare to have cervical involvement in the initial period of RA. If a patient has isolated cervical spine involvement without peripheral arthritis, it is highly likely that inappropriate investigations and delayed treatment may occur. Any damage that occurs in cervical spine may cause symptoms varying from slight instability to atlantoaxial subluxation, spinal cord and brain stem compression and even death. Therefore, physician should be aware that there may be isolated cervical involvement, albeit rare, in patients with RA. In this report, we presented a case of RA presenting with cervical spine involvement without peripheral arthritis to underline the importance of this kind of involvement in clinical practice. We also briefly reviewed other cases similar to ours in light of literature.

Rheumatoid Arthritis Affecting the Upper Cervical Spine: Biomechanical Assessment of the Stabilizing Ligaments

Diameters of anterior and posterior atlantodental intervals (AADI and PADI) are diagnostically conclusive regarding ongoing neurological disorders in rheumatoid arthritis. MRI and X-ray are mostly used for patients' follow-up. This investigation aimed at analyzing these intervals during motion of cervical spine, when transverse and alar ligaments are damaged. AADI and PADI of 10 native, human cervical spines were measured using lateral fluoroscopy, while the spines were assessed in neutral position first, in maximal inclination second, and in maximal extension at last. First, specimens were evaluated under intact conditions, followed by analysis after transverse and alar ligaments were destroyed. Damage of the transverse ligament leads to an increase of the AADI's diameter about 0.65 mm in flexion and damage of alar ligaments results in significant enhancement of 3.59 mm at mean. In extension, the AADI rises 0.60 mm after the transverse ligament was cut and 0.90 mm when the alar ligaments are damaged. After all ligaments are destroyed, AADI assessed in extension closely resembles AADI at neutral position. Ligamentous damage showed an average significant decrease of the PADI of 1.37 mm in the first step and of 3.57 mm in the second step in flexion, while it is reduced about 1.61 mm and 0.41 mm in the extended and similarly in the neutrally positioned spine. Alar and transverse ligaments are both of obvious importance in order to prevent AAS and movement-related spinal cord compression. Functional imaging is necessary at follow-up in order to identify patients having an advanced risk of neurological disorders.

Factors That Predict Risk of Cervical Instability in Rheumatoid Arthritis Patients

STUDY DESIGN

Retrospective data analysis.

OBJECTIVE

To identify factors affecting the atlantodental interval, the Ranawat value, and subaxial translation after rheumatoid arthritis (RA) diagnosis. In addition, factors predictive for cervical spine instability (CSI) development after RA diagnosis were examined.

SUMMARY OF BACKGROUND DATA

Development of CSI affects the prognosis and mortality of RA patients. Previous studies described that obesity is associated with reduced radiographic joint damage in RA patients. We hypothesized that body mass index (BMI) is also associated with radiographic cervical damage in RA patients.

METHODS

Cervical radiographs were taken at full flexion, neutral position, and full extension to measure the geometric length of the anterior atlantodental interval, the Ranawat value, and subaxial translation. These values were entered into multivariable linear regression analysis based on potential associated factors. Hazard ratios were calculated to identify independent factors predictive of CSI.

RESULTS

Of the patients diagnosed with RA between January 2005 and August 2015, 1611 who underwent at least one cervical radiograph were included. After adjusting for sex, age, BMI category, CSI, rheumatoid factor, and RA medication, multivariate analysis revealed that the risk of atlantoaxial subluxation in the underweight and normal BMI groups was about 1.6-fold (hazard ratio, 1.63; 95% CI, 1.10-2.43; P = 0.015) and 1.7-fold higher, respectively, than that in the obese group, and that the risk of vertical subluxation was about 2.5-fold (hazard ratio, 2.52; 95% CI, 1.32-4.83; P = 0.005) higher in the underweight group than in the obese group. We also found that the rheumatoid factor positivity was a predictive risk factor for CSI development.

CONCLUSION

We identified risk factors predictive for CSI occurrence after RA diagnosis through cervical radiograph assessment. We found that BMI was an independent predictor for development of CSI. Further large-scale prospective studies are required to confirm these findings.

LEVEL OF EVIDENCE

3.

The outcomes of instrumented posterolateral lumbar fusion in patients with rheumatoid arthritis

Aims

The aims of this study were to evaluate the clinical and radiological outcomes of instrumented posterolateral fusion (PLF) performed in patients with rheumatoid arthritis (RA).

Methods

A total of 40 patients with RA and 134 patients without RA underwent instrumented PLF for spinal stenosis between January 2003 and December 2011. The two groups were matched for age, gender, bone mineral density, the history of smoking and diabetes, and number of fusion segments. The clinical outcomes measures included the visual analogue scale (VAS) and the Korean Oswestry Disability Index (KODI), scored before surgery, one year and two years after surgery. Radiological outcomes were evaluated for problems of fixation, nonunion, and adjacent segment disease (ASD). The mean follow-up was 36.4 months in the RA group and 39.1 months in the non-RA group.

Results

Both groups had significant improvement in symptoms one year after surgery, while the RA group showed some deterioration of outcome scores owing to complications during the second year after surgery. Complications occurred at a higher rate in the group with RA (19 patients, 47.5%) than in those without RA (23 patients, 17.1%) (p < 0.001). A total of 15 patients in the RA group (37.5%) required revision surgery, mainly for implant failure and post-operative infection.

Discussion

Multimodal approaches should be considered when performing instrumented PLF in patients with RA to reduce the rate of complications, such as problems of fixation, post-operative infection and nonunion. Take home message: Specific strategies should be undertaken in order to optimise outcomes in patients with rheumatoid arthritis. Cite this article: Bone Joint J 2016;98-B:102–8.

Successful Treatment of Occipital Radiating Headache Using Pulsed Radiofrequency Therapy

Rheumatoid arthritis (RA) is a chronic inflammatory disease involving multiple joints. The cervical spine is often affected, and cases involving atlantoaxial joint can lead to instability. Anterior atlantoaxial subluxation in RA patients can lead to posterior neck pain or occipital headache because of compression of the C2 ganglion or nerve. Here, we report the successful treatment of a RA patient with occipital radiating headache using pulsed radiofrequency therapy at the C2 dorsal root ganglion.

Subaxial cervical spine involvement in symptomatic rheumatoid arthritis patients: Comparison with cervical spondylosis

OBJECTIVE

To investigate the frequency, location, characteristics, and clinical significance of subaxial involvement (below C1-C2) in a series of patients with rheumatoid arthritis (RA) and symptomatic involvement of the cervical spine.

METHODS

A total of 41 patients with RA were examined via cervical spine magnetic resonance imaging (MRI). A comparative analysis of the incidence of the different types of subaxial lesions was performed between these patients and 41 age- and sex-matched patients with symptomatic cervical spondylosis.

RESULTS

Stenosis of the spinal canal was found at the subaxial level in 85% of RA patients, and at the atlantoaxial level in 44%. Comparative analysis between these patients and the cervical spondylosis patients revealed significant differences in the types and frequencies of subaxial lesions. For both conditions, signs of discopathy and end-plate osteophytosis were the most common abnormalities observed on magnetic resonance imaging (MRI). However, in the RA patients these abnormalities coincided with subchondral bone and ligamentous acute inflammatory changes and with secondary destruction (vertebral instability) or repair (vertebral ankyloses). Only evidence of subaxial myelopathy was significantly associated with an increased risk of neurological dysfunction among the RA patients [Ranawat class II or III; P = 0.01; odds ratio (OR) = 11.43], although subaxial cord compression tended toward a significant association with the risk of neurological dysfunction (P = 0.06; OR = 3.95).

CONCLUSION

Subaxial stenosis seems to be the consequence of both the inflammatory process and mechanical-degenerative changes. Despite its frequency, it was not usually related to the occurrence of myelopathy symptoms, not even in cases with MRI evidence of spinal cord compression.

Surgical outcomes of long spinal fusions for scoliosis in adult patients with rheumatoid arthritis

OBJECT

In this study, the authors compared outcomes and complications in patients with and without rheumatoid arthritis (RA) who underwent surgery for spinal deformity.

METHODS

The authors searched the Johns Hopkins University database for patients with RA (Group RA) and without RA (Group NoRA) who underwent long spinal fusion for scoliosis by 3 surgeons at 1 institution from 2000 through 2012. Groups RA and NoRA each had 14 patients who were well matched with regard to sex (13 women/1 man and 12 women/2 men, respectively), age (mean 66.3 years [range 40.5–81.9 years] and 67.6 years [range 51–81 years]), follow-up duration (mean 35.4 months [range 1–87 months] and 44 months [range 24–51 months]), and number of primary (8 and 8) and revision (6 and 6) surgeries. Surgical outcomes, invasiveness scores, and complications were compared between the groups using the nonpaired Student t-test (p < 0.05).

RESULTS

For Groups RA and NoRA, there were no significant differences in the average number of levels fused (10.6 [range 9–17] vs 10.3 [range 7–17], respectively; p = 0.4), the average estimated blood loss (2892 ml [range 1300–5000 ml] vs 3100 ml [range 1700–5200 ml]; p = 0.73), or the average invasiveness score (35.5 [range 21–51] vs 34.5 [range 23–58]; p = 0.8). However, in Group RA, the number of major complications was significantly higher (23 vs 11; p < 0.001), the number of secondary procedures was significantly higher (14 vs 6; p < 0.001), and the number of minor complications was significantly lower (4 vs 12; p < 0.001) than those in Group NoRA.

CONCLUSIONS

Long spinal fusion in patients with RA is associated with higher rates of major complications and secondary procedures than in patients without RA.

Cervical myelopathy due to atraumatic odontoid fracture in patients with rheumatoid arthritis: A case series

To highlight the risk of cervical myelopathy due to occult, atraumatic odontoid fracture in patients with rheumatoid arthritis, we retrospectively reviewed radiographic findings and clinical observations for 7 patients with this disorder. This fracture tends to occur in patients with long-lasting rheumatoid arthritis and to be misdiagnosed as simple atlantoaxial dislocation. Since this fracture causes multidirectional instability between C1 and C2 and is expected to have poor healing potential due to bone erosion and inadequate blood supply, posterior spinal arthrodesis surgery is indicated upon identification of the fracture to prevent myelopathy.

The surgical management of the rheumatoid spine: Has the evolution of surgical intervention changed outcomes?

Context:

Surgery for the rheumatoid cervical spine has been shown to stabilize the unstable spine; arrest/improve the progression of neurological deficit, help neck pain, and possibly decelerate the degenerative disease process. Operative intervention for the rheumatoid spine has significantly changed over the last 30 years.

Aims:

The purpose of this study was to review all cases of cervical rheumatoid spine requiring surgical intervention in a single unit over the last 30 years.

Materials and Methods:

A prospectively-maintained spine database was retrospectively searched for all cases of rheumatoid spine, leading to a review of indications, imaging, Ranawat and Myelopathy Disability Index measures, surgical morbidity, and survival curve analysis.

Results:

A total of 224 cases were identified between 1981 and 2011. Dividing the data into three time-epochs, there has been a significant increase in the ratio of segment-saving Goel-Harms C1-C2: Occipitocervical fixation (OCF) surgery and survival has increased between 1981 and 2011 from 30% to 51%. Patients undergoing C1-C2 fixation were comparatively less myelopathic and in a better Ranawat class preoperatively, but postoperative outcome measures were well-preserved with favorable mortality rates over mean 39.6 months of follow-up. However, 11% of cases required OCF at mean 28 months post-C1-C2 fixation, largely due to instrumentation failure (80%).

Conclusion:

We present the largest series of surgically managed rheumatoid spines, revealing comparative data on OCF and C1-C2 fixation. Although survival has improved over the last 30 years, there have been changes in medical, surgical and perioperative management over that period of time too confounding the interpretation; however, the analysis presented suggests that rheumatoid patients presenting early in the disease process may benefit from C1 to C2 fixation, albeit with a proportion requiring OCF at a later time.

Effect of the transverse ligament rupture on the biomechanics of the cervical spine under a compressive loading

BACKGROUND

In order to diagnosis a transverse ligament rupture in the cervical spine, clinicians normally measure the atlas-dens interval by using CT scan images. However, the impact of this tear on the head and neck complex biomechanics is not widely studied. The transverse ligament plays a very important role in stabilizing the joint and its alteration may have a substantial effect on the whole head and neck complex.

METHODS

A finite element model consisting of bony structures along with cartilage, intervertebral discs and all ligaments was developed based on CT and MRI images. The effect of head weights (compressive load) of 30 N to 57 N was investigated in the cases of intact and ruptured transverse ligament joints. The model was validated based on experimental studies investigating the response of the cervical spine under the extension-flexion moment.

FINDINGS

The predictions indicate a significant alteration of the kinematics and load distribution at the facet joints of the cervical spine with a transverse ligament tear. The vertebrae flexion, the contact force at the facets joints and the atlas-dens interval increase with the rupture of the transverse ligament and are dependent to the head weight.

INTERPRETATION

A transverse ligament tear increases the flexion angle of the head and the vertebrae as well as the atlas-dens interval. The atlas-dens interval reaches a critical value when the compressive loading exceeds 40 N. Supporting the head after an injury should be considered to avoid compression of the spinal cord and permanent neurologic damage.

Cervical spine instability in rheumatoid arthritis

Rheumatoid arthritis (RA) is the most common inflammatory disease of the cervical spine (CS). After hands and feet, CS is the most commonly involved segment, being present in more than half of the patients with RA. Especially in the CS, RA may cause degeneration of ligaments, leading to laxity, instability and subluxation of the vertebral bodies. This is often asymptomatic or symptoms are erroneously attributed to peripheral manifestations. Otherwise, this may cause compression of spinal cord (SC) and medulla oblongata leading to severe neurologic deficits and even sudden death. Owing to its potentially debilitating and life-threatening sequelae, inevitable progression once neurologic deficits occur and the poor medical condition of afflicted patients, CS involvement remains a priority in the diagnosis and its treatment will remain a challenge. The surgical approach aims a solid fixation of the upper cervical spine, giving stability, preventing neurologic deterioration and injury to the SC, leading to improved neurologic function, vascular integrity and maintenance of sagittal balance. The recent advances in surgical techniques, complete understanding of the anatomy and precise preoperative evaluation led to safer and more effective procedures that have decreased complication rates. Based on the fact that when a patient becomes myelopathic the rate of long-term mortality increases and the chance of neurologic recovery decreases, many authors agree that early surgical intervention, before the onset of neurologic deficits, gives a more satisfactory outcome. However, the timing when a prophylactic stabilization should occur is poorly defined, and so, patients with radiographic instability but without evidence of neurologic deficit are still the most difficult to manage.

Lumbar scoliosis in rheumatoid arthritis: epidemiological research with a DXA cohort

STUDY DESIGN

A retrospective cross-sectional study.

OBJECTIVE

The aim of this study was to identify the prevalence of and risk factors for lumbar scoliosis in patients with rheumatoid arthritis (RA) using lumbar images obtained from dual-energy x-ray absorptiometry (DXA).

SUMMARY OF BACKGROUND DATA

The prevalence of lumbar scoliosis in the normal adult population has been reported, but that in patients with RA remains unclear.

METHODS

Subjects comprised 241 patients with RA who underwent annual DXA. Cobb angles of the lumbar spine were measured by lumbar anteroposterior DXA and the prevalence of lumbar scoliosis (curvature ≥10°) was calculated. Correlations between lumbar scoliosis and potential risk factors (age, sex, duration of RA, T score of lumbar spine and hip, medications for RA [daily predonisolone dose, use of biological agents] and osteoporosis, disease activity score-C-reactive protein, progression stage and functional classification of RA, and severity of hand deformity were analyzed.

RESULTS

The prevalence of lumbar scoliosis in patients with RA was 32.0%. Mean Cobb angle was 7.1º ± 5.5º among all subjects, compared with 13.6º ± 4.4º (range, 10º-32º) among subjects with scoliosis. Subjects with scoliosis were significantly older (67.8 yr) than those without (61.6 yr, P < 0.0001). The daily prednisolone dose was significantly higher in subjects with scoliosis (4.14 mg) than in those without (3.46 mg, P = 0.0389). The T score of the hip was significantly smaller in subjects with scoliosis (-1.79) than in those without (-1.26, P = 0.0005). A multivariate logistic regression analysis revealed age as the sole risk factor for lumbar scoliotic changes in patients with RA (odds ratio, 1.068; 95% confidence interval, 1.031-1.107; P = 0.0003).

CONCLUSION

The prevalence of lumbar scoliosis in patients with RA was 32.0%, about 3- or 4-times higher than its prevalence as obtained from previous reports of DXA cohorts irrespective of RA. Increased age represented an independent risk factor for lumbar scoliosis in patients with RA.

LEVEL OF EVIDENCE

4.

Artrodesis C1C2 con tornillos transarticulares en artritis reumatoidea: experiencia y revisión de la literatura

OBJETIVO: Describir los resultados clínicos e imagenológicos utilizando la técnica de fijación C1 C2 con tornillos transarticulares y asas de alambre en pacientes portadores de AR en un seguimiento a largo plazo y revisar la literatura actual. MÉTODO: Entre los años 2002 y 2006, 11 pacientes (9 mujeres y 2 hombres) con inestabilidad C1 C2 secundaria a AR fueron intervenidos quirúrgicamente. Se realizó fijación C1 C2 con tornillos transarticulares por vía posterior más asas de alambre y aplicación de injerto óseo autólogo de cresta ilíaca. Se registró Índice de Ranawat pre y posoperatorio, Distancia Anterior Atlas Odontoides (DAAO) pre y posoperatorio, tiempo operatorio, días de hospitalización, complicaciones intra y posoperatorias y tiempo de consolidación radiológica, con un seguimiento promedio de 34 meses. RESULTADOS: Todos los pacientes presentaron mejoría del Índice de Ranawat en el postoperatorio. La DAAO preoperatoria promedio fue de 11,9 mm (DS ± 2,57), rango 7 a 16, y la DAAO postoperatoria promedio fue de 3 mm (DS ± 1,20), rango 2 a 6. El tiempo quirúrgico fue de 94 minutos en promedio y el promedio de días de hospitalización fue de 7 días. No se presentaron complicaciones intraoperatorias. Un caso presentó seroma de herida operatoria que requirió tratamiento quirúrgico. El tiempo de consolidación fue en promedio 14 semanas. CONCLUSIÓN: La artrodesis atlantoaxial con tornillos y amarras es una buena alternativa para el manejo de la inestabilidad C1-C2 en pacientes portadores de AR, consiguiendo buenos resultados clínicos e imagenológicos en un seguimiento a largo plazo.

A biomechanical rationale for C1-ring osteosynthesis as treatment for displaced Jefferson burst fractures with incompetency of the transverse atlantal ligament

Nonsurgical treatment of Jefferson burst fractures (JBF) confers increased rates of C1-2 malunion with potential for cranial settling and neurologic sequels. Hence, fusion C1-2 was recognized as the superior treatment for displaced JBF, but sacrifies C1-2 motion. Ruf et al. introduced the C1-ring osteosynthesis (C1-RO). First results were favorable, but C1-RO was not without criticism due to the lack of clinical and biomechanical data serving evidence that C1-RO is safe in displaced JBF with proven rupture of the transverse atlantal ligament (TAL). Therefore, our objectives were to perform a biomechanical analysis of C1-RO for the treatment of displaced Jefferson burst fractures (JBF) with incompetency of the TAL. Five specimens C0-2 were subjected to loading with posteroanterior force transmission in an electromechanical testing machine (ETM). With the TAL left intact, loads were applied posteriorly via the C1-RO ramping from 10 to 100 N. Atlantoaxial subluxation was measured radiographically in terms of the anterior antlantodental interval (AADI) with an image intensifier placed surrounding the ETM. Load-displacement data were also recorded by the ETM. After testing the TAL-intact state, the atlas was osteotomized yielding for a JBF, the TAL and left lateral joint capsule were cut and the C1-RO was accomplished. The C1-RO was subjected to cyclic loading, ramping from 20 to 100 N to simulate post-surgery in vivo loading. Afterwards incremental loading (10-100 N) was repeated with subsequent increase in loads until failure occurred. Small differences (1-1.5 mm) existed between the radiographic AADI under incremental loading (10-100 N) with the TAL-intact as compared to the TAL-disrupted state. Significant differences existed for the beginning of loading (10 N, P = 0.02). Under physiological loads, the increase in the AADI within the incremental steps (10-100 N) was not significantly different between TAL-disrupted and TAL-intact state. Analysis of failure load (FL) testing showed no significant differences among the radiologically assessed displacement data (AADI) and that of the ETM (P = 0.5). FL was Ø297.5 +/- 108.5 N (range 158.8-449.0 N). The related displacement assessed by the ETM was Ø5.8 +/- 2.8 mm (range 2.3-7.9). All specimens succeeded a FL >150 N, four of them >250 N and three of them >300 N. In the TAL-disrupted state loads up to 100 N were transferred to C1, but the radiographic AADI did not exceed 5 mm in any specimen. In conclusion, reconstruction after displaced JBF with TAL and one capsule disrupted using a C1-RO involves imparting an axial tensile force to lift C0 into proper alignment to the C1-2 complex. Simultaneous compressive forces on the C1-lateral masses and occipital condyles allow for the recreation of the functional C0-2 ligamentous tension band and height. We demonstrated that under physiological loads, the C1-RO restores sufficient stability at C1-2 preventing significant translation. C1-RO might be a valid alternative for the treatment of displaced JBF in comparison to fusion of C1-2.

Rheumatoid Arthritis of the Craniovertebral Junction

BACKGROUND

Rheumatoid arthritis (RA) is the most common inflammatory disease involving the spine. It has a predilection for involving the craniocervical spine. Despite widespread involvement of the cervical spine with RA, few patients need surgery. The 3 major spinal manifestations of RA in the cervical spine are basilar invagination, atlantoaxial instability, and subaxial subluxations. Surgical management of RA involving the craniovertebral junction remains a challenge despite a decline in severe cases and an improvement in surgical techniques.

METHODS

We conducted an exhaustive review of English-language publications discussing RA involving the craniovertebral junction. We paid special attention to publications detailing modern surgical management of these conditions. In addition, we outline our own surgical experience with such patients.

RESULTS

We discuss alternative surgical methods for treating basilar invagination, atlantoaxial instability, and concurrent subaxial subluxations. We detail our surgical technique for transoral odontoidectomy, occipital cervical fusion, and atlantoaxial fusion. We detail the use of spinal surgical navigation in both of these procedures.

CONCLUSION

Surgical management of RA remains a challenging field. There clearly has been a decrease in cases of mutilating RA involving the craniovertebral junction. Surgical techniques for managing these conditions have steadily improved.

EVALUATION OF THE CERVICAL SPINE AMONG PATIENTS WITH RHEUMATOID ARTHRITIS

Objective: To evaluate the prevalence of cervical spine abnormalities among patients with rheumatoid arthritis and correlate the imaging findings with the clinical state. Methods: A cross-sectional study on 35 patients was carried out at the School of Medicine of the Federal University of Goiás (UFG) in 2004. The following were evaluated: age, use of medications and the clinical picture of pain and neurological characteristics. The erythrocyte sedimentation rate (ESR) and rheumatoid factor were tested, and radiographs of the cervical spine were produced in anteroposterior, lateral and dynamic views. To evaluate the influence of the variables on the emergence of instabilities, univariate and multivariate logistic regression tests were used (p < 0.05). Results: Among the 35 patients evaluated, 13 (37.1%) presented a stable cervical spine. Out of the 22 patients with instability, six presented more than one type. Atlantoaxial instability was found in 15 patients, with a mean anterior atlantodental distance of 3.40 mm in the neutral lateral radiographic view and 6.54 mm in the lateral view with flexion. Basilar invagination was found in five patients and subaxial subluxation in seven patients. Two thirds of the asymptomatic patients had instabilities. Bicipital hyperreflexia presented statistically significant correlations with atlantoaxial instability (p = 0.024) and subaxial instability (p = 0.01). Age at diagnosis correlated with subaxial instability (p = 0.02). Conclusions: The prevalence of cervical instability was 62.9 % (22/35). The most frequent instabilities were: atlantoaxial subluxation (42.9 %), subaxial subluxation (20%) and basilar invagination (14.3%). The correlation between instabilities and clinical signs and symptoms was poor. The patients with subaxial subluxation presented disease onset at a younger age. Dynamic radiography was important for diagnosing atlantoaxial subluxation.

The kinematic relationships of the upper cervical spine

STUDY DESIGN

A retrospective radiographic study.

OBJECTIVE

To elucidate the kinematic relationships of the upper cervical spine.

SUMMARY OF BACKGROUND DATA

To our knowledge, few reports have described the kinematic relationships of the upper cervical spine in patients with general age-related cervical spondylosis.

METHODS

We performed Kinetic magnetic resonance imaging for 295 consecutive patients experiencing neck pain without neurologic symptoms. Subjects with rheumatoid arthritis, traumatic history, and severe degenerative changes in the upper cervical spine were excluded. Anterior atlantodens interval (AADI) and the cervicomedullary angle in 3 different postures were measured, and the variations in each value between flexion and neutral (F-N), neutral and extension (N-E), and flexion and extension (F-E) were calculated. The subjects were classified into 3 groups according to the space available for the cord values (A: <or=14 mm, B: 14-15 mm, C: >or=15 mm).

RESULTS

AADI significantly increased from extension to flexion posture, however, no significant differences were observed in every posture among the groups. F-N variation in AADI showed no significant differences among the groups; however, N-E variation between Groups A and C and between Groups B and C and F-E variation between Groups A and C showed significant differences. The cervicomedullary angle significantly increased from flexion to extension posture, however, no significant differences were observed in every posture among the groups. Angle variations among the groups showed no significant differences, except for F-N angle variation between Groups B and C. None of the variations in AADI and the cervicomedullary angle were significantly correlated.

CONCLUSION

Our results suggest that only the kinematics of the atlantoaxial movement, especially the posterior movement, was greatly affected by the narrowing of space available for the cord. The central atlantoaxial joint may be closely related to the mechanisms for protecting the spinal cord by restriction of the atlantoaxial movement.

Subaxial subluxation after atlantoaxial transarticular screw fixation in rheumatoid patients

The most common cervical abnormality associated with rheumatoid arthritis (RA) is atlantoaxial subluxation, and atlantoaxial transarticular screw fixation has proved to be one of the most reliable, stable fixation techniques for treating atlantoaxial subluxation. Following C1-C2 fixation, however, subaxial subluxation reportedly can bring about neurological deterioration and require secondary operative interventions. Rheumatoid patients appear to have a higher risk, but there has been no systematic comparison between rheumatoid and non-rheumatoid patients. Contributing radiological factors to the subluxation have also not been evaluated. The objective of this study was to evaluate subaxial subluxation after atlantoaxial transarticular screw fixation in patients with and without RA and to find contributing factors. Forty-three patients who submitted to atlantoaxial transarticular screw fixation without any concomitant operation were followed up for more than 1 year. Subaxial subluxation and related radiological factors were evaluated by functional X-ray measurements. Statistical analyses showed that aggravations of subluxation of 2.5 mm or greater were more likely to occur in RA patients than in non-RA patients over an average of 4.2 years of follow-up, and postoperative subluxation occurred in the anterior direction in the upper cervical spine. X-ray evaluations revealed that such patients had a significantly smaller postoperative C2-C7 angle, and that the postoperative AA angle correlated negatively with this. Furthermore, anterior subluxation aggravation was significantly correlated with the perioperative atlantoaxial and C2-C7 angle changes, and these two changes were strongly correlated to each other. In conclusion, after atlantoaxial transarticular screw fixation, rheumatoid patients have a greater risk of developing subaxial subluxations. The increase of the atlantoaxial angel at the operation can lead to a decrease in the C2-C7 angle, followed by anterior subluxation of the upper cervical spine and possibly neurological deterioration.

Columna cervical reumática

La artritis reumatoidea (AR) afecta a millones de personas en el mundo. Hasta un 86% de los pacientes presenta alteraciones a nivel cervical. Los patrones de inestabilidad cervical asociados a la artritis reumatoidea son: inestabilidad atlanto-axial, impactación atlanto-axial y subluxación subaxial. Una vez que aparecen alteraciones neurológicas su progresión puede ser rápida y llevar incluso a la muerte. El tratamiento de la AR es fundamentalmente médico. Los medicamentos y esquemas actuales podrían prevenir o retardar la aparición de alteraciones a nivel atlanto-axial. El examen clínico y radiológico periódico permite detectar a los pacientes que ya presentan compromiso neurológico, o a los que están en riesgo de desarrollarlo, en cuyos casos debe considerarse la cirugía como opción terapéutica. La recuperación neurológica post-quirúrgica depende del nivel de compromiso neurológico previo, lo que refuerza la importancia de la detección y derivación precoz de los pacientes en riesgo. El tratamiento quirúrgico debe llevarse a cabo en centros especializados, por grupos multidisciplinarios. Esto, junto con la intervención temprana, ayudaría a reducir las complicaciones peri-operatorias.

[Surgery of the cervical spine in rheumatoid arthritis. Diagnostics and indication]

The cervical spine is often affected in rheumatoid arthritis. Beside destructive changes, instabilities can occur, mainly in the upper cervical spine. Typical symptoms are missing so that routine x-ray examinations are needed to prevent severe consequences up to death. AP/lateral cervical spine x-rays and lateral functional x-rays are the standard diagnostic tool. Depending on the findings, further neurological examination and MRI must be initiated. Aim is the early recognition, respectively prevention of myelopathy. Therapy includes stage dependent conservative and surgical measures.

Atlantoaxial transarticular screw fixation with posterior wiring using polyethylene cable: facet fusion despite posterior graft resorption in rheumatoid patients

STUDY DESIGN

A comparative retrospective study on the posterior graft union and the facet fusion in atlantoaxial transarticular screw fixation.

OBJECTIVE

To evaluate the posterior graft union and the facet fusion in atlantoaxial transarticular screw fixation when a polyethylene (PE) cable was used in rheumatoid and nonrheumatoid patients.

SUMMARY OF BACKGROUND DATA

In atlantoaxial transarticular screw fixation, metal wires or cables for posterior bone graft fixation can cause intraoperative or delayed spinal cord compression. PE cables do not have the risk, but there has been no comparative report. Also, a precise evaluation on the posterior graft union and the facet fusion has not been reported.

METHODS

Thirty-eight patients who submitted to atlantoaxial transarticular screw fixation and posterior bone graft without any concomitant operation were followed up for more than 2 years. The posterior graft union and the facet fusion were evaluated by functional radiographs and computed tomography scans.

RESULTS

Seven patients showed the posterior graft nonunion. All of them were rheumatoid patients and received PE cable wiring for posterior internal fixation. However, 5 of the 7 cases presented stable C1-C2 with the facet fusion demonstrated by functional radiographs and computed tomography scans, achieving an overall fusion rate of 95%.

CONCLUSION

In atlantoaxial transarticular screw fixation, the use of PE cable and rheumatoid background are 2 of the unfavorable factors for the posterior graft union. However, atlantoaxial transarticular screws can bring the facet fusion despite the posterior graft failure in such cases.

Treatment of upper cervical spine involvement in rheumatoid arthritis patients

The cervical spine, especially the upper cervical spine, is a common focus of destruction by rheumatoid arthritis (RA). Because of its potentially debilitating and life-threatening sequelae, cervical spine involvement remains a priority in the diagnosis and treatment of RA. Many studies show that early surgical intervention gives a more satisfactory outcome. Surgery aims to establish spinal stability and to prevent neurological deterioration and injury to the spinal cord, leading to improved neurological function. The recent sophisticated screw-rod-plate technique allows one to obtain a solid fixation of the upper cervical spine with a high possibility of bone union even in RA patients. Although surgery of the occipitoatlantoaxial region is a challenge with many possibilities of serious complications, recent advances in the surgical technique, complete understanding of the anatomy, and precise preoperative evaluation have decreased complication rates. Early consultation with a specialized spine surgeon is mandatory once cervical involvement is suspected in an RA patient because once the patient becomes myelopathic, the rate of long-term mortality increases and the chance of neurological recovery decreases.

Cervical high-intensity intramedullary lesions without spinal cord compression in achondroplasia

OBJECT

In the authors' experience, the appearance of a cervical high-intensity intramedullary (CHII) lesion on magnetic resonance (MR) images in the absence of local spinal cord compression is frequently observed in patients with achondroplasia, although it has been mentioned only sporadically in the literature. Hence, the authors conducted a retrospective study in a consecutive single-center series of patients with achondroplasia to determine the prevalence and imaging features of this entity. They also reviewed the literature.

METHODS

Cervical MR imaging studies obtained to establish diagnoses in 25 adult patients with achondroplasia and assessed at the Leiden University Medical Center after neurogenic claudication developed were evaluated for the presence of a CHII lesion. Imaging features of the lesion were described, and a literature search was performed. The CHII lesion was demonstrated in 16 of 25 adult patients with achondroplasia (64%) in the absence of local spinal cord compression. All lesions were located at the C-2 level and appeared to be confined to the gray matter. The CHII lesion was associated with local spinal cord thinning, most likely representing focal atrophy. In their literature search the authors found no description of the CHII lesion in adults, although its presence has been mentioned as a peculiarity in the pediatric achondroplastic population.

CONCLUSIONS

In this large series of adults with achondroplasia and symptomatic neurogenic claudication, a CHII lesion was frequently depicted on imaging studies, but it remains a fully explored imaging phenomenon. Its cause and clinical relevance require investigation, as does its prevalence in the general achondroplastic population.

Complex Deformities of the Cervical Spine

Cervical deformities arise from a multitude of causes, including genetic, congenital, inflammatory, degenerative, and iatrogenic etiologies. They often require surgical intervention for treatment of pain, progressive structural decompensation, and neurologic deterioration. Although congenital and hereditary causes of cervical deformity require specialized attention to particular clinical features and operative considerations, postsurgical (iatrogenic) cervical deformity after surgery is the most common single cause. Appropriate treatment involves careful selection of conservative and aggressive measures and familiarity with advanced surgical techniques that allow for the safe correction of these challenging deformities. Flexible deformities can be managed with single-staged procedures, whereas fixed deformities require two-staged or even three-staged procedures. Staged surgery for fixed cervical deformities can achieve up to 28 degrees of angular correction and 31% translational correction.

Efficacy of computer-assisted pedicle screw insertion for cervical instability in RA patients

We evaluated the efficacy of the computer-assisted cervical pedicle screw insertion, compared with those inserted without the help of the system on the cervix of rheumatoid arthritis (RA) patients. Eighty-six cervical pedicle screws were inserted without the help of the system. Of the 86, 59 screws were in non-RA patients with degenerative spine, and 27 were in RA patients. The accuracy of the screw insertions was evaluated by a CT-based method. Then, 25 screws were inserted with the system into the cervical spines between C2 and C6 in RA patients (Navigation group). The efficacy of the system was assessed by the CT-based method, compared with 27 screws inserted without the system (Conventional group). The screws in RA patients tended to be more deviated than those in non-RA patients. In Conventional group, four screws (15%) were placed far laterally, and two (7%), far medially. In contrast, no screw was placed far laterally or medially in Navigation group (P < 0.05).

Long-term incidence of subaxial cervical spine instability following cervical arthrodesis surgery in patients with rheumatoid arthritis

OBJECTIVE

Cervical spine deformities are well-known complications of RA. A 5- to 20-year follow-up of 51 consecutive rheumatoid patients who underwent posterior cervical arthrodesis is presented to evaluate the recurrence of instability and need for further surgery.

METHODS

We conducted a retrospective review of the clinical features of 11 men and 40 women with an established diagnosis of RA and associated cervical deformities who underwent cervical spine surgery at the Mayo Clinic (Rochester, MN) between 1979 and 1990. Their mean age was 61 +/- 10 years (SD), and their duration of RA averaged 21 +/- 8.9 years (SD). There were 22 patients who presented with myelopathy, 7 with radiculopathy, and 22 with instability/neck pain. There were 33 patients with AAS, 2 with SMO process into the foramen magnum, 8 with SAS, and 8 with combinations of these. Preoperative reduction was followed by decompression and fusion using wiring techniques and autologous bone graft. Postoperative halo orthosis was provided for at least 3 months. The mean follow-up was 8.3 +/- 6 years (SD).

RESULTS

There were 31 patients (61%) who underwent atlantoaxial arthrodesis, 17 patients (33%) who underwent subaxial, and 3 patients (6%) who underwent occipitocervical arthrodesis. During follow-up, 39% (13/33) of patients with AAS developed nonsymptomatic (6) or symptomatic/unstable (7) SASs subsequent to C1-C2 fusion. The latter 7 patients (21%) subsequently required extension of their arthrodesis. Adjacent segment disease was most common at the C3-C4 interspace after atlantoaxial fusion in 62% (8/13). Among the 8 patients who underwent isolated cervical fusion for SAS, 1 patient (1/8, 12%) developed adjacent instability after a fall and required extension of the previous fusion. No secondary procedure was required for the 6 patients initially stabilized by C1-(C6-T1) fusions for combinations of AAS + SAS. None of the patients initially treated by C1-C2 arthrodesis for AAS progressed to SMO.

CONCLUSIONS

The incidence of subaxial instability in patients with rheumatoid disease who underwent cervical arthrodesis may be higher than previously reported, indicating the need for continued follow-up in these patients. Adjacent segment disease may be most common at the C3-C4 level following atlantoaxial fusion. Early stabilization of the C1-C2 complex in the patients with AAS may potentially prevent progression of SMO.