Multiple Sclerosis (MS) is a chronic autoimmune disease of the central nervous system, affecting the brain and spinal cord. The immune system attacks the myelin sheath, the protective layer surrounding nerve fibers. This damage disrupts electrical signals between the brain and the body, leading to unpredictable symptoms. While walking ability is a major concern, most people with MS can walk, though the degree of difficulty and need for support often change over time.
How MS Affects Walking Ability
Walking, or gait, requires coordination between neurological and muscular systems. MS impairs this function through demyelination and nerve fiber damage in the brain and spinal cord areas controlling movement and sensation. This damage slows or blocks messages to the leg muscles, resulting in gait impairment.
Chronic fatigue is a primary factor affecting walking. This is an overwhelming, persistent exhaustion that drastically reduces muscle endurance and walking distance. A person might walk normally in the morning, but the accumulated effort can cause noticeable gait problems later in the day.
Walking is also compromised by spasticity, which is involuntary stiffness and tightness, particularly in the legs. This interferes with the smooth swing of the leg during a step. Another common issue is foot drop, a weakness in the muscles that lift the front of the foot, causing the toes to drag and increasing the risk of tripping.
Coordination and balance problems, medically termed ataxia, are a consequence of nerve damage, particularly in the cerebellum. Ataxia leads to an unsteady, swaying gait, often causing people to walk with their feet spread wide apart to maintain stability. Furthermore, sensory deficits, such as numbness in the feet, prevent a person from feeling the ground beneath them, leading to a loss of awareness of where their feet are placed and contributing to unsteadiness.
Strategies for Maintaining Gait and Balance
Proactive, consistent intervention offers the best chance of maintaining walking function and independence. Physical therapy (PT) and occupational therapy (OT) are central to this strategy, providing individualized programs to address specific mobility deficits. A physical therapist will conduct a detailed gait analysis to identify issues like reduced step length or poor ankle control before designing a treatment plan.
PT includes targeted exercises to improve mobility. Stretching is valuable for managing spasticity and improving flexibility. Strength training focuses on the core, hips, and leg muscles to stabilize the walking pattern and improve overall endurance. Balance exercises, such as tandem standing or weight shifts, improve coordination and directly reduce the risk of falling. Aquatic therapy, or exercising in a pool, is also recommended because the buoyancy supports the body, allowing for gentle resistance training.
Pharmaceutical management helps control symptoms that interfere with mobility. Dalfampridine is specifically approved to improve walking speed in people with MS. Spasticity is commonly managed with muscle relaxants such as baclofen or tizanidine, which reduce stiffness and involuntary spasms. For localized, severe spasticity, injections of botulinum toxin can temporarily relax targeted muscles. Managing these symptoms through medication and consistent exercise reduces the physical effort required to walk, helping to conserve energy and combat fatigue.
Utilizing Mobility Assistance and Adaptive Technology
When walking is compromised, external aids and technologies help maintain independence and safety. A physical or occupational therapist can recommend the most appropriate device based on individual needs, such as a cane for mild balance issues or a walker for greater instability. Walkers and rollators offer support and a place to rest, which is beneficial when fatigue is pronounced.
For foot drop, an ankle-foot orthosis (AFO) is a brace that stabilizes the ankle and holds the foot in a neutral position. The AFO prevents the toe from dragging, making walking safer and more efficient. For severe fatigue or covering longer distances, a manual or power wheelchair allows a person to conserve energy and participate more fully in daily life.
Adaptive technology also includes home modifications that improve accessibility and reduce accident risk. Simple changes like installing grab bars in the bathroom, using ramps to eliminate steps, and ensuring clear pathways support safe movement. These external supports enable continued engagement in activities of daily living.
Understanding Long-Term Mobility Progression
The trajectory of mobility loss in MS is highly variable and depends on the specific form of the disease. While most people with MS experience some walking difficulty, the majority remain able to walk for many years after diagnosis. The disease course includes relapsing-remitting MS, which features periods of symptom worsening followed by recovery, and progressive forms, where disability steadily increases.
The Expanded Disability Status Scale (EDSS) is the standardized tool neurologists use to measure disability progression, with scores ranging from 0 (no disability) to 10 (death due to MS). The EDSS places a strong emphasis on walking ability, using it as the primary metric for scores between 4.5 and 7.0. For example, a score of 4.5 indicates a person can walk without aid but has significant disability, and a score of 6.0 indicates the need for a cane or crutch to walk 100 meters.
Advancements in disease-modifying therapies have significantly altered the long-term outlook, especially for those with relapsing-remitting MS. These treatments reduce the frequency of relapses, slowing the accumulation of permanent disability. Although approximately 80% of people with MS develop some gait problems within 10 to 15 years of onset, many individuals never require the consistent use of a wheelchair.