Treatment of upper cervical spine involvement in rheumatoid arthritis patients

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.

Vertebrobasilar Infarction Due to Bow Hunter's Syndrome in a Patient with Rheumatoid Arthritis: A Case Report

A 60-year-old woman with a 37-year history of rheumatoid arthritis (RA) had a sudden onset of headache. Head MRI showed acute multiple infarctions in the vertebrobasilar region, and MR angiography showed stenosis of the right vertebral artery (VA). 3D-CT angiography of the craniovertebral junction showed atlantoaxial subluxation and stenosis of the right VA just distal to the transverse foramen of C2, which was due to osteophytes and degenerative changes secondary to RA. Digital subtraction angiography clearly demonstrated occlusion of the right VA during rightward head rotation. Based on those findings, rotatory instability at C1-2 was considered as the primary cause of the vertebrobasilar infarctions, and Bow Hunter's syndrome was diagnosed. The patient underwent C1-5 posterior fixation, and brain infarction has not recurred.

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.

Occipital and external acoustic meatus to axis angle: a useful predictor of oropharyngeal space in rheumatoid arthritis patients with atlantoaxial subluxation

OBJECTIVE

Dyspnea and/or dysphagia is a life-threatening complication after occipitocervical fusion. The occiput-C2 angle (O-C2a) is useful for preventing dyspnea and/or dysphagia because O-C2a affects the oropharyngeal space. However, O-C2a is unreliable in atlantoaxial subluxation (AAS) because it does not reflect the translational motion of the cranium to C2, another factor affecting oropharyngeal area in patients with rheumatoid arthritis (RA) who have reducible AAS. The authors previously proposed the occipital and external acoustic meatus to axis angle (O-EAa; i.e., the angle made by McGregor's line and a line joining the external auditory canal and the middle point of the endplate of the axis [EA line]) as a novel, useful, and powerful predictor of the anterior-posterior narrowest oropharyngeal airway space (nPAS) distance in healthy subjects. The aim of the present study was to elucidate the validity of O-EAa as an indicator of oropharyngeal airway space in RA patients with AAS.

METHODS

The authors investigated 64 patients with RA. The authors collected lateral cervical radiographs at neutral position, flexion, extension, protrusion, and retraction and measured the O-C2a, C2-C6, O-EAa, anterior atlantodental interval (AADI), and nPAS. Patients were classified into 2 groups according to the presence of AAS and its mobility: group N, patients without AAS; and group R, patients with reducible AAS during dynamic cervical movement.

RESULTS

Group N had a significantly lower AADI and O-EAa than group R in all but the extension position. The O-EAa was a better predictor for nPAS than O-C2a according to the mixed-effects models in both groups (marginal R2: 0.510 and 0.575 for the O-C2a and O-EAa models in group N, and 0.250 and 0.390 for the same models, respectively, in group R).

CONCLUSIONS

O-EAa was superior to O-C2a in predicting nPAS, especially in the case of AAS, because it affects both O-C2a and cranial translational motion. O-EAa would be a useful parameter for surgeons performing occipitocervical fusion in patients with AAS.

Neurologic Manifestations of Rheumatoid Arthritis

Neurologic manifestations of rheumatoid arthritis (RA) range in severity from mild paresthesias in the hand from carpal tunnel syndrome to sudden death due to impingement of the medulla by an eroded, vertically subluxed dens. Most neurologic complications are a consequence of articular inflammation and damage that leads to compression of adjacent structures of the central or peripheral nervous systems. Rare but serious extra-articular manifestations include inflammation of the meninges and ischemic neuropathies due to necrotizing arteritis of the vasa vasorum. Medical therapy with synthetic disease-modifying antirheumatic drugs and biological agents has diminished the incidence of serious neurologic manifestations in RA.

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.

Rheumatoid arthritis-induced lateral atlantoaxial subluxation with multiple vertebrobasilar infarctions

STUDY DESIGN

Case report.

OBJECTIVE

To highlight the probability that lateral atlantoaxial subluxation (AAS) exists in patients with rheumatoid arthritis (RA) and induces vertebrobasilar infarctions that are more foregrounded than compressive myelopathy.

SUMMARY OF BACKGROUND DATA

Although lateral subluxation is a well-known subtype of AAS, a case of cerebral ischemia associated with lateral AAS has not been reported before.

METHODS

A 52-year-old male with a 6-year history of RA had a sudden onset of visual field defect and mild right cerebellar ataxia. Head magnetic resonance imaging revealed acute multiple infarctions in the vertebrobasilar area, and magnetic resonance angiography revealed stenosis of the left vertebral artery (VA). Lateral radiograph of the cervical spine in the neutral position revealed atlanto-occipital assimilation and anterior AAS. T2-weighted sagittal images on cervical magnetic resonance imaging revealed high signal intensity in the spinal cord at C1-C2. Cerebral angiography revealed right VA occlusion and severe stenosis of the left V3 segment of VA. Three-dimensional computed tomography angiography of the craniovertebral junction revealed lateral AAS, which was due to severe erosive changes of the facet joints, and the left V3 portion was stenosed by a bony component. During conservative therapy, the patient experienced left occulomotor nerve palsy due to a second stroke.

RESULTS

Two months later, the patient underwent occipitocervical posterior fusion with an iliac bone graft. His postoperative course was uneventful, and the left VA stenosis disappeared. At the 45-month follow-up, he had no further infarctions. Bony fusion was radiologically confirmed, and 3-dimensional computed tomography angiography revealed good patency of the affected left VA.

CONCLUSION

In patients with RA, the potential risk of AAS should be recognized. Lateral AAS in particular may induce cerebral ischemia by positional VA occlusion in advanced stages of the disease.

LEVEL OF EVIDENCE

N/A.

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.

Quantification of synovitis in the cranio-cervical region: dynamic contrast enhanced and diffusion weighted magnetic resonance imaging in early rheumatoid arthritis--a feasibility follow up study

OBJECTIVE

To test the feasibility of dynamic contrast enhanced (DCEI) and diffusion weighted (DWI) magnetic resonance imaging (MRI) for quantifying synovitis of the cranio-cervical (C-C) region in patients with early rheumatoid arthritis (RA) and neck pain at the beginning and at a six month follow up.

METHODS

27 patients with duration of RA of less than 24 months and neck pain were studied with standard qualitative MRI evaluation and two quantitative MRI methods (DCEI and DWI) at the level of atlantoaxial joints. Rate of early enhancement (REE), enhancement gradient (Genh) and apparent diffusion coefficient (ADC) were extracted from DCEI and DWI data. MRI was coupled with clinical assessment and radiographic imaging.

RESULTS

Using standard qualitative MRI evaluation, unequivocal active synovitis (grade 2 or 3 contrast enhancement) was proved in 16 (59%) patients at baseline and 14 (54%) at follow up. DCEI and DWI measurements confirmed active synovitis in 25 (93%) patients at baseline and 24 (92%) at follow up. Average REE, Genh and ADC values decreased during follow up, however the difference was not statistically significant (p>0.05). Both qualitative and quantitative MRI methods confirmed active inflammatory disease in the C-C region following therapy although all clinical criteria showed signs of improvement of the peripheral disease.

CONCLUSIONS

The study proved the feasibility of DCEI and DWI MRI for quantifying synovitis of the C-C region in patients with early RA and neck pain. Both techniques can be used as additional method for evaluation of synovitis of the C-C region in RA.

Remodeling of C2 facet deformity prevents recurrent subluxation in patients with chronic atlantoaxial rotatory fixation: a novel strategy for treatment of chronic atlantoaxial rotatory fixation

STUDY DESIGN

A retrospective case series.

OBJECTIVE

To propose a novel treatment strategy for chronic atlantoaxial rotatory fixation (AARF).

SUMMARY OF BACKGROUND DATA

Treatment strategy for chronic or recurrent AARF remains controversial. We have previously reported that a deformity of the superior facet of the axis (C2 facet deformity), which is frequently observed in patients with chronic AARFs, is a risk factor for recurrent dislocation. In this article, we report seven consecutive cases of chronic AARF who underwent closed manipulation followed by external halo fixation and maintained good reduction with the remodeling of the C2 facet deformity.

METHODS

Seven girls with a chronic AARF who sustained torticollis for an average of 4.6 months after the onset were referred to our clinic. Closed manipulation by careful manipulation under general anesthesia followed by external immobilization with a halo vest was performed in all cases. Radiographic findings and clinical courses were retrospectively reviewed with approvals by the institutional review board.

RESULTS

Three-dimensional computed tomography images before reduction revealed persistent atlantoaxial subluxation and the C2 facet deformity in the dislocated side in all cases. Follow-up three-dimensional computed tomographic scans demonstrated the remodeling of the C2 facet deformity at an average of 2.8 months after successful reduction of subluxation. Subsequently, the halo vests were removed and gentle neck range of motion exercise was started in all cases. The normal cervical range of motion was obtained 2 weeks after the removal of halo vests in five cases, whereas the range of motion remained limited in two cases. At a mean follow-up of 17.4 months, neither symptoms nor recurrence of subluxation occurred in all cases.

CONCLUSION

Chronic irreducible and recurrent unstable AARF can be managed successfully by careful closed manipulation followed by halo fixation, if the C1 and C2 have not been osseously fused. The remodeling of the C2 facet deformity detected on follow-up CT scans can be a useful radiographic parameter to determine the appropriate period of halo fixation in this new treatment strategy obviating the need for surgical intervention.