Can multiple sclerosis (MS) present with an inability to use legs?

Multiple Sclerosis Can Present with Inability to Use Legs

Yes, multiple sclerosis (MS) commonly presents with bilateral leg weakness or inability to use legs, which is a manifestation of spinal cord involvement in the disease. 1, 2

Clinical Presentation of MS Affecting Mobility

• MS typically presents in young adults (ages 20-30) with various neurological symptoms including unilateral optic neuritis, partial myelitis, sensory disturbances, or brainstem syndromes that develop over several days 3
• 50-80% of people with MS have balance and gait dysfunction, with over 50% experiencing falls at least once each year 2
• Spinal cord involvement is seen in 80-90% of patients with MS, most commonly affecting the cervical cord, which can lead to lower extremity weakness 4
• Patients with primary progressive MS tend to have more spinal cord involvement than patients with relapsing-remitting MS 4

Diagnostic Considerations for MS-Related Leg Weakness

• When evaluating bilateral leg weakness, MS should be considered in the differential diagnosis alongside other central nervous system causes such as spinal cord compression or myelopathy and spinal stenosis 1
• MRI is essential for diagnosis, with spinal cord lesions fulfilling part of the diagnostic criteria for MS according to the 2016 MAGNIMS criteria 4
• Diagnosis is made based on a combination of signs and symptoms, radiographic findings (MRI T2 lesions), and laboratory findings (cerebrospinal fluid-specific oligoclonal bands), which are components of the 2017 McDonald Criteria 3
• Symptomatic lesions in the spinal cord can contribute to both dissemination in space (DIS) and dissemination in time (DIT) criteria for MS diagnosis 4

Distinguishing MS from Other Causes of Bilateral Leg Weakness

• The differential diagnosis for bilateral leg weakness includes:
  • Peripheral nervous system causes: Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy (CIDP), and toxic or metabolic neuropathies 1
  • Central nervous system causes: spinal cord compression, myelopathy, spinal stenosis, and MS 1
  • Neuromuscular junction and muscle disorders: myasthenia gravis and inflammatory myopathies 1
• MS-related leg weakness is typically accompanied by other signs of central nervous system involvement, such as sensory changes, hyperreflexia, and Babinski sign, which help distinguish it from peripheral causes 3, 5

Impact of MS-Related Mobility Impairment

• Difficulty walking is reported by 41% of people with MS, including 13% with inability to walk at least twice a week 6
• Among those with difficulty walking, 70% consider it the most challenging aspect of having MS 6
• Of those with inability to walk at least twice a week, 74% report disruption of their daily lives 6
• Only 34% of people with MS with difficulty walking remain employed, indicating significant impact on socioeconomic status 6

Management of MS-Related Leg Weakness

• Disease-modifying therapies (DMTs) can reduce clinical relapses and MRI lesions, potentially slowing progression of disability 3
• Balance training should be offered to patients with MS who have balance disorders 4
• Effective interventions for balance include trunk training, task-oriented intervention, force platform biofeedback, Tai Chi, aquatic therapy, and partial body weight support treadmill training 4
• Rehabilitation is a key component of management, with four phases recommended for people with MS: pre-habilitation, acute rehabilitation, subacute rehabilitation, and community rehabilitation 4

Prognosis

• At 15 years from MS onset, approximately 50% of patients are disabled to the point of requiring at least a cane to walk a half block 7
• Early age at onset, female sex, relapsing-remitting course at onset, and optic neuritis or sensory symptoms at onset are associated with a more favorable course 7
• Life expectancy is not substantially altered in patients with MS, particularly in the early years of the illness 7

Clinical Pearls

• Communication between people with MS and physicians regarding difficulty walking is often suboptimal; 39% of people with MS report they never or rarely discussed it with their doctor 6
• Special care must be taken in diagnosing MS in those with progressive onset and atypical presentations; additional evidence from CSF and visual evoked potentials may help secure the diagnosis 4
• Early recognition and treatment of MS is critical to prevent disability progression, as axonal damage can occur early in the disease course 3