Presentation and course
Rheumatoid arthritis is a chronic inflammatory arthropathy of unknown etiology, characterized by persistent synovitis that typically involves peripheral joints in a symmetric distribution. The hallmark pathology, synovial inflammation causing cartilage destruction, bone erosion, and subsequent joint deformity, follows a variable course. Some patients experience only mild oligoarticular disease of brief duration, whereas others develop relentlessly progressive destruction with profound functional impairment. A substantial subset involves other organ systems, including the nervous system, which forms the focus of this review.
The 2010 ACR/EULAR classification criteria, which replaced the 1987 criteria to enable earlier diagnosis and treatment initiation, are presented in Table 1. This revision reflects a fundamental shift in approach: rather than requiring features of established disease such as rheumatoid nodules or radiographic erosions, the current criteria emphasize serologic markers and joint-involvement patterns that permit classification before irreversible damage occurs (02).
Table 1. 2010 ACR/EULAR Classification Criteria for Rheumatoid Arthritis
Domain | Category | Points |
Joint involvement | 1 large joint
2 to 10 large joints
1 to 3 small joints
4 to 10 small joints
More than 10 joints (1 or more small) | 0
1
2
3
5 |
Serology | Negative RF and ACPA
Low-positive RF or ACPA
High-positive RF or ACPA | 0
2
3 |
Acute-phase reactants | Normal CRP and ESR
Abnormal CRP or ESR | 0
1 |
Symptom duration | Less than 6 weeks
6 or more weeks | 0
1 |
A score of 6 or higher is required for classification as definite rheumatoid arthritis. Criteria apply to patients with at least one joint with definite clinical synovitis not better explained by another disease. ACPA = anticitrullinated protein antibody; RF = rheumatoid factor.
|
Extra-articular manifestations occur in nearly one in four patients, with rheumatoid factor positivity, smoking, and older age at onset identified as predisposing factors (22). These manifestations affect the skin, heart, lungs, and eyes, but the nervous system involvement that concerns us here may occur in either the central or peripheral compartments. Neurologic complications of rheumatoid arthritis are summarized in Table 2. Although peripheral nervous system involvement represents the most common clinically apparent neurologic complication, the frequency of cervical spine abnormalities is consistently underestimated.
Table 2. Neurologic Complications of Rheumatoid Arthritis
Category | Manifestations |
Central nervous system | Aseptic meningitis, cerebral vasculitis, rheumatoid pachymeningitis |
Spinal | Cervical stenosis or myelopathy, atlantoaxial subluxation, lumbar stenosis or radiculopathy |
Peripheral nervous system | Entrapment neuropathies (carpal tunnel, ulnar, tarsal tunnel), sensory or sensorimotor polyneuropathy, vasculitic neuropathy (mononeuritis multiplex), demyelinating neuropathy |
Treatment-related | TNF-alpha inhibitor demyelination, JAK inhibitor cardiovascular or venous thromboembolism events, progressive multifocal leukoencephalopathy (rituximab, other biologics) |
Peripheral neuropathy. Peripheral neuropathies represent the most common neurologic manifestation of rheumatoid arthritis, though their true prevalence has only recently been appreciated. Electrodiagnostic studies detect peripheral neuropathy in one third to two thirds of patients when systematically assessed, a substantial proportion of which remain subclinical until testing is performed (01). This high burden of unrecognized neuropathy has important implications for patient counseling and symptom attribution.
Entrapment neuropathies. Carpal tunnel syndrome stands as the most frequent peripheral neuropathy in rheumatoid arthritis, affecting 10% to 30% of patients depending on diagnostic criteria, with electrophysiological confirmation in approximately 10% to 17% (19). The association is robust: a 2025 population-based study demonstrated a 2.23-fold increased risk of carpal tunnel syndrome in patients with rheumatoid arthritis, with the intriguing finding that carpal tunnel syndrome was present even 2 or more years before the diagnosis of rheumatoid arthritis, suggesting shared pathophysiology or that median nerve compression may be an early feature of the inflammatory process (09).
The clinical presentation mirrors that seen in the general population: pain or paresthesia affecting the lateral palm and lateral three fingers, often with nocturnal exacerbation and provocation by repetitive hand use. Tinel sign at the wrist is typically present, and thenar atrophy with weakness of abductor pollicis brevis indicates more advanced compression. Nerve ultrasound in rheumatoid arthritis-associated carpal tunnel syndrome reveals an inflammatory pattern (tenosynovitis and synovitis) rather than the marked nerve swelling characteristic of idiopathic cases; median nerve cross-sectional area averages 10.6 mm² compared to 17.7 mm² in idiopathic carpal tunnel syndrome (29). This distinction has diagnostic implications; clinical symptoms alone carry low specificity in patients with rheumatoid arthritis, making electrodiagnostic confirmation or ultrasound assessment advisable.
Ulnar neuropathy at the elbow is the second most common entrapment neuropathy, presenting with medial hand paresthesia and, in severe cases, intrinsic hand weakness. Tarsal tunnel syndrome occurs in up to 33% of patients with rheumatoid arthritis, particularly those with foot involvement (16), though diagnostic certainty is complicated by the lack of standardized electrodiagnostic criteria and the multiple mimics (lumbar radiculopathy, polyneuropathy, musculoskeletal pain) that commonly coexist in this population.
Polyneuropathy. Beyond entrapment, patients with rheumatoid arthritis develop axonal sensory or sensorimotor polyneuropathy at rates exceeding those of the general population. The typical presentation involves distal sensory symptoms (numbness, tingling, burning) with gradual proximal spread, accompanied by diminished or absent ankle reflexes and, eventually, distal weakness. Risk factors independently associated with neuropathy include older age, longer disease duration, number of affected small joints (adjusted OR 1.62 for polyneuropathy) (01), and most strikingly, anti-CCP antibody positivity, which carries a relative risk of 14.27 (95% CI 1.37–148.26) in multivariate analysis (28). This strong serologic association suggests that the autoimmune process itself, rather than mechanical or metabolic factors alone, drives nerve damage.
Vasculitic neuropathy. Mononeuritis multiplex, the hallmark of vasculitic neuropathy, presents with an acute or subacute onset of painful motor and sensory deficits following individual nerve distributions in a stepwise pattern. This complication occurs in the context of active, untreated rheumatoid arthritis and typically accompanies constitutional symptoms and other manifestations of systemic disease. Paradoxically, vasculitis often emerges when articular disease appears “burnt out.” With effective disease-modifying therapy, vasculitic neuropathy has become rare, though it remains a medical emergency when it occurs; deficits are often irreversible if treatment is delayed, and historical 5-year mortality reached 43% (24). Over time, confluent deficits from multiple nerve infarctions may mimic a distal symmetric polyneuropathy, obscuring the underlying diagnosis.
Demyelinating neuropathy. Chronic inflammatory demyelinating polyneuropathy is rarely seen in rheumatoid arthritis and typically represents a coexisting condition rather than a direct manifestation of the disease. However, demyelinating neuropathy may occur as a complication of TNF-alpha inhibitor therapy, a distinction with important treatment implications.
Central nervous system manifestations. Central nervous system vasculitis and aseptic meningitis are rare but potentially devastating manifestations of rheumatoid arthritis. They may present in isolation or concurrently, with mental status changes, focal neurologic deficits, headaches, or seizures (34). The average age of onset is 62 years, and CNS involvement tends to occur later in the disease course, though in 17% of patients, it represents the presenting manifestation of rheumatoid arthritis. Active systemic disease is present in approximately 35% of cases, meaning quiescent joints do not exclude CNS involvement.
Rheumatoid meningitis. Fewer than 200 cases of rheumatoid meningitis have been reported. A systematic review of 130 cases established the clinical phenotype: transient focal neurologic signs occur in 65% of patients, systemic symptoms in 51%, episodic headache in 50%, and neuropsychiatric alterations in 48% (34). Joint manifestations are present in only 27% at presentation, underscoring that meningitis may occur with minimal articular disease.
Serological markers prove highly sensitive for diagnosis; rheumatoid factor positivity reaches 90% and anti-CCP antibody positivity 89%, with elevated inflammatory markers (CRP 82%, ESR 82%) nearly universally present (34). MRI demonstrates leptomeningeal enhancement in most cases; the “mismatch DWI/FLAIR” pattern of patchy diffusion restriction without corresponding FLAIR hyperintensity has been proposed as a potentially useful diagnostic sign. CSF biomarkers, including markedly elevated anti-CCP antibodies (up to 19,600 IU/mL), CXCL-13, and IL-6, may aid diagnosis and monitoring.
Treatment centers on high-dose corticosteroid induction (methylprednisolone 500 to 1000 mg daily for 3 to 5 days) followed by maintenance therapy. TNF-alpha inhibitors should be avoided, as cases of TNF-alpha-induced aseptic meningitis have been reported. Tocilizumab and rituximab have shown efficacy as maintenance biologics.
Cerebral rheumatoid vasculitis. A 2025 comprehensive review of 37 histologically confirmed cases documented dramatic improvement in outcomes with modern treatment (37). The typical patient is female (73%), with a median age of 51 years and a median rheumatoid arthritis duration of 12 years before neurologic onset. Mental status changes (54%), paralysis (46%), and seizures (43%) predominate clinically. The most striking finding concerns prognosis: mortality decreased from 90% before 1980 to 15% after 1980, reflecting the impact of immunosuppressive therapy. Combination corticosteroids plus immunosuppressants achieved 82% efficacy, compared with 64% mortality with corticosteroids alone. Cyclophosphamide remains the first-line therapy, with rituximab emerging as an alternative.
Spinal stenosis.
Cervical spine disease. Cervical spine involvement, whether due to instability, pannus formation, or accelerated degenerative arthritis, represents a common manifestation that can appear early in the disease course (27). Although upper cervical involvement, such as atlantoaxial subluxation, is considered the classic pattern, patients with rheumatoid arthritis actually develop subaxial cervical stenosis more frequently.
A 2024 study of 240 patients found anterior atlantoaxial subluxation in 10.4% of patients, with one-third of affected patients reporting no neck pain—a finding that underscores the importance of screening asymptomatic patients (03). A prospective Japanese cohort study of 634 patients over 10 years demonstrated that pre-existing atlantoaxial subluxation significantly predicted vertical subluxation aggravation (17). Longstanding disease has been associated with more severe cervical involvement (05).
The impact of biological therapy on cervical spine progression carries important nuance; biologics prevent de novo cervical lesions (only 8% progression in patients without pre-existing disease) but fail to halt progression of existing lesions (80% progression in patients with established subluxation) (15). This finding emphasizes that once structural damage begins, biomechanical progression continues regardless of disease activity control.
Presentation ranges from asymptomatic to nonspecific neck pain or limited range of motion. Cervical radiculopathy produces arm pain, positional paresthesia, or weakness in patterns determined by the involved roots. Upper cervical involvement (C2–C4) may present with posterior headaches or auricular paresthesia. Myelopathy manifests as arm weakness, impaired hand dexterity, gait instability, or bladder urgency. Cervicomedullary junction involvement may cause lower facial paresthesia due to spinal trigeminal nucleus compression or brainstem symptoms, such as Lhermitte sign, vertigo, or dysphagia.
Examination findings of radiculopathy include dermatomal sensory loss, myotomal weakness, and depressed reflexes. Myelopathy produces hyperreflexia, Hoffman or Babinski signs, diffuse weakness, Romberg sign, and wide-based gait--findings that may occur without prominent pain symptoms.
Lumbar spine disease. Lumbar involvement remains underrecognized. Lower back pain affects 25% ot 40% of patients in the literature, whereas spondylolisthesis occurs in 46.5% (vs. 26.6% controls, p< 0.01) and vertebral fractures in 45.9% (vs. 33.9% controls, p=0.01) (32). Thoraco-lumbar scoliosis shows a trend toward increased prevalence (29.7% vs. 22.9% in controls, p=0.08), though this does not reach statistical significance (32). Rheumatoid arthritis has been identified as an independent risk factor for reoperation and lumbar fusion within 2 years after laminectomy (11).
Surgical outcomes in rheumatoid arthritis carry substantially elevated risk. A 2022 meta-analysis of 703 patients versus 2,569 controls found surgical site infection risk 2.29-fold higher, overall complication risk 1.61-fold higher, implant-related complication risk 3.93-fold higher, and reoperation risk 2.45-fold higher. Hospital stays averaged 4.62 days longer (30). Critically, steroid dependence drives much of this risk; a propensity-matched multicenter analysis found 30-day complication rates of 17% in patients with steroid-dependent rheumatoid arthritis versus 3% in non-rheumatoid arthritis controls, whereas steroid-independent patients showed outcomes comparable to the general population (18).
Prognosis and complications
Neurologic complications of treatment. Infectious complications of classical immunosuppressive therapy with corticosteroids, cyclophosphamide, azathioprine, methotrexate, or mycophenolate include opportunistic infections with mycobacteria, fungi, and viruses, as well as Epstein-Barr virus-associated CNS lymphoma. Although monoclonal antibodies target the immune system more specifically than these traditional agents, they carry distinct neurologic risks that have emerged with widespread use.
TNF-alpha inhibitors. TNF-alpha inhibitors increase relapse risk and worsen outcomes in patients with multiple sclerosis, and their use has been implicated in demyelinating disease even in the absence of a history of multiple sclerosis. Presentations include optic neuritis, clinically isolated syndrome, or multiple sclerosis-like disease, occurring most often with infliximab, etanercept, or adalimumab (20). British Society for Rheumatology Biologics Register data documented 35 demyelinating events among 13,489 patients, yielding an incidence rate of approximately 20 per 100,000 patient-years (33). Average onset occurs approximately 5 months after therapy initiation, with paresthesias (65%), optic neuritis (40%), and confusion (25%) as leading presentations (23).
Population-based studies suggest the risk may be lower than initially estimated, and a Danish study found no association between TNF-alpha inhibition and neuroinflammatory complications. Most cases occur within the first year of treatment (20), and neurologic symptoms tend to improve or stabilize in most patients (23). TNF-alpha inhibitors are contraindicated in patients with a personal or family history of multiple sclerosis.
Demyelinating peripheral neuropathy, usually chronic inflammatory demyelinating polyradiculoneuropathy, has also been described with TNF-alpha inhibitors (04). Unlike central demyelinating syndromes, peripheral demyelinating neuropathies may progress even after drug withdrawal, and response to steroids is suboptimal. Long-term intravenous immunoglobulin is often required.
JAK inhibitors. The ORAL Surveillance trial fundamentally altered the risk-benefit calculus for JAK inhibitors (36). This randomized trial of 4,362 patients with rheumatoid arthritis aged 50 years or older with at least one cardiovascular risk factor found that tofacitinib failed non-inferiority versus TNF inhibitors for major adverse cardiovascular events and malignancy. Venous thromboembolism risk was dose-dependently elevated (approximately five-fold higher with tofacitinib 10 mg versus TNF inhibitors over 6 years) with prior venous thromboembolism, morbid obesity, and age 65 or older as key risk factors.
Risk concentrates in specific subgroups: age 65 or older, current or former smokers, and prior cardiac events. Post-hoc analysis found the risk difference was not apparent in patients under 65 years who never smoked. Real-world evidence has been conflicting; the STAR-RA study of 102,263 patients showed no increased myocardial infarction or stroke risk in routine care, though a subcohort mimicking ORAL Surveillance criteria reproduced the trial signal.
Herpes zoster with neurologic complications represents another concern. Network meta-analysis demonstrated elevated risk across the JAK inhibitor class, with Asian ethnicity, older age, and higher doses as risk factors. Case reports document herpes zoster encephalitis during tofacitinib therapy, and varicella-zoster virus vasculopathy can cause stroke, arterial dissection, or spinal cord infarction. Herpes zoster vaccination before JAK inhibitor initiation is now recommended.
IL-6 inhibitors. Tocilizumab and sarilumab demonstrate favorable neurologic safety profiles, with no established association with demyelinating disease.
Rituximab. Progressive multifocal leukoencephalopathy has been reported with rituximab and other monoclonal antibodies used in rheumatologic disorders (06). The estimated risk is 2.56 per 100,000 exposed patients--approximately 1 case per 25,000 to 40,000 treated. All confirmed cases had at least one progressive multifocal leukoencephalopathy risk factor independent of rituximab, and no consistent latency pattern has emerged. There is no proven effective therapy; discontinuation of immunosuppression is advisable. Late-onset neutropenia affects 1.3% of patients, with a median onset of 4.5 to 5 months after infusion (26).
