Multiple Sclerosis Rehabilitation, An Issue of Physical Medicine and Rehabilitation Clinics (eBook)

Shana L. Johnson, George H. Kraft (Autoren)

eBook Download: EPUB

2013 | 1. Auflage
225 Seiten
Elsevier Health Sciences (Verlag)
978-0-323-24234-9 (ISBN)

Infos

This issue of Physical Medicine and Rehabilitation Clinics devoted to Multiple Sclerosis is Guest Edited by Drs. George Kraft and Shana Johnson. Articles in this issue include: Gait Impairment and Optimizing Mobility in MS; Spasticity management; Exercise; ADLs and Adaptive Equipment; Movement Disorders; Fatigue Management; Cognitive Impairment and Management; Neurogenic Bladder and Bowel; Visual Issues; Depression and Pain; Adaptive Technology and Vocational Issues; Aging; Evoked Potentials; and Research.

Textauszug

Gait Impairment and Optimizing Mobility in Multiple Sclerosis

Victoria Stevens, PT, NCS∗[e-mail], Kelli Goodman, PT, DPT, Katherine Rough, PT, DPT, NCS and George H. Kraft, MD, MS,     University of Washington Medicine, Seattle, WA, USA

∗Corresponding author.

Multiple sclerosis (MS) is an immune-mediated disease that causes demyelination and degeneration within the brain and spinal cord. This may result in many impairments, including impaired ambulation, muscle weakness, abnormal tone, visual disturbances, decreased sensation, and fatigue. Rehabilitation helps patients with MS maximize independence by helping to manage and minimize impairments. Deficits seen in ambulation should be addressed to improve energy efficiency and reduce falls. Compensation through appropriate prescription of assistive devices, bracing, and wheelchairs will help improve safety. Rehabilitation can make a significant impact on achieving and maintaining quality of life and independence.

Keywords

• Multiple sclerosis • Gait • Falls • Balance • Rehabilitation

Key points

• Multiple sclerosis (MS) is an immune-mediated disease that causes demyelination and axonal degeneration within the brain and spinal cord.

• Impairments include impaired ambulation, muscle weakness, abnormal tone, visual disturbances, decreased sensation, and fatigue.

• Rehabilitation helps patients with MS maximize independence by helping to manage and minimize impairments.

• Deficits seen in ambulation should be addressed to improve energy efficiency and reduce falls.

• Compensation through appropriate prescription of assistive devices, bracing, and wheelchairs will help improve safety.

• Rehabilitation can make a significant impact on achieving and maintaining quality of life and independence.

Introduction

Multiple sclerosis (MS) is an immune-mediated disease that causes both demyelination and axonal degeneration within the brain and spinal cord. These pathologic changes in the nerves of the central nervous system (CNS) may cause many impairments, commonly including muscle weakness, increased tone, bladder dysfunction, cognitive impairment, visual impairment, sensory changes, and fatigue. One of the signature characteristics of MS is its predilection for affecting muscles and sensation innervated by the most caudal nerves: muscles and sensory structures of the feet, legs, and bladder. This is because of the cumulative impact of lesions throughout the CNS; nerve dysfunction is greatest over the longest pathways: those between the cortex and lower lumbo-sacral roots (the “cumulative impact” explanation).1

There are currently a number of medications approved by the Food and Drug Administration (FDA) that can reduce the number of exacerbations and slow disease progression (disease-modifying treatments or DMTs) and one medication that may improve walking (dalfampridine [Ampyra]), none of them provide a cure.2 Rehabilitation aimed at maximizing patients’ current levels of function and increasing their overall independence is an important adjunct to DMTs in MS care.3

Gait abnormalities

Patients with MS have a range of gait abnormalities, including decreased step length, decreased cadence, reduced joint movement, and increased variability of most gait parameters. These changes lead to decreased velocity, reduced endurance, increased metabolic costs, and reduced community ambulation.4 Even in those individuals with minimal disability (expanded disability status scale [EDSS] ≤3.5),5 analysis shows that persons with MS walk slower, with fewer, shorter, wider steps; have increased variability in time between steps; and spend more time in double support compared with controls.6

Several types of abnormal gait patterns can arise as a result of MS; the specific pattern is dependent on the location of the lesions within the CNS. Some of the more common gait patterns are described in the following section and include spastic paresis, cerebellar ataxia, and sensory ataxia. Often a combination of patterns is seen.

Gait Patterns

Spastic paresis

Spastic paresis results from insufficient supraspinal recruitment of motor neurons in specific leg muscles during the gait cycle. Depending on which muscles are weak, limitations can be seen in stance or swing phase resulting in a variety of impairments including foot drop (ankle-foot weakness); knee hyperextension or hyperflexion; anterior, posterior, or lateral trunk lean; circumduction; and hip drop.7 The most common pattern in MS is asymmetric spastic paraparesis, but all patterns can be seen, including monoparesis, hemiparesis, and tetraparesis.

Ankle-foot weakness in its mildest and most common form, it is manifested by 2 characteristics:

1. Weakness of ankle dorsiflexion (and sometimes associated weak push-off)

2. Motor fatigue

Motor fatigue is greater weakness with greater duration of use and is also accounted for by the likelihood of increased sequential demyelinated regions encountered over the longest pathways in the CNS. This is caused by conduction block seen in partially demyelinated motor pathways over an extended period of activation, and may be associated with increase in body temperature or other causes.8 An easy assessment of this condition is to observe the wear pattern on the front of the sole of a shoe.

Cerebellar ataxia

Cerebellar ataxia occurs as a result of damage to the cerebellum or its connections and is characterized by incoordination, poor postural control, dysmetria, dysdiadochokinesia, and increased variability in stride length, as well as wide base of support and stooped trunk position.6

Sensory ataxia

Sensory ataxia results from damage to the dorsal columns of the spinal cord that transmit proprioception, or from damage in the processing centers for afferent information, such as the thalamus or the parietal lobe. This gait is characterized by postural instability, heavy heel strikes, poor kinematics from lower limb joint position, and decreased gait velocity. This may be tested in clinic with the Romberg test: the patients with MS is asked to stand, feet together, and can do so with eyes open but not when closed. A more quantitative method of assessing posterior column function is with tibial nerve somatosensory evoked potentials (SEPs) (see the article by Kraft elsewhere in this issue for further exploration of this topic).9

Weakness

Overall muscle force generated during a contraction is lower in patients with MS because of reduced central motor drive and consequent muscle recruitment, reduced muscle metabolic response, and muscle atrophy due to disuse. Strength training is known to promote neural adaptations, such as improved motor unit activation and synchronization of firing rates, both of which deteriorate rapidly with inactivity.7

Strength training has been shown to be beneficial in several MS studies. Guitierrez and colleagues10 showed that an 8-week program of resistance training improved gait kinematics. The study found that resistance training facilitates positive changes in gait (specifically, longer strides), more time spent in swing phase, and less time in the stance and double-support phase. This study also showed improved toe clearance, which is a significant factor in decreasing falls. A trend toward improvement in the self-reported EDSS scale, which relies heavily on ambulation as a determinant of disability, was also documented.10 Kraft and colleagues11 found improved function, strength, and psychosocial well-being in a group of patients with MS after a 3-month course of strength training. DeBolt and McCubbin12 found that a home-based resistance program was well tolerated, caused no exacerbations in this population, and improved leg extension muscle power. This research demonstrates the critical importance of initiating an individualized home exercise program in a patient with MS. It is important that these patients are referred to physical therapy early on in their disease process to maximize strength and independence. Rehabilitation can make a significant impact on achieving and maintaining quality of life and independence.

Spasticity

Spasticity is commonly seen in the MS population. An increased level of tone is associated with higher levels of disability. Barnes and colleagues13 investigated the prevalence of spasticity in 68 subjects and identified that 97% had spasticity in at least one leg that was present at a clinically significant level in 47%.

There are several muscles that commonly interfere with ambulation in the MS population. Hypertonic plantarflexors cause the foot to point down, making toe clearance in the swing phase of gait difficult, resulting in...

Produkt-Details

• Erscheint lt. Verlag: 1.1.2014
• Sprache: englisch
• Themenwelt: Medizin / Pharmazie ► Medizinische Fachgebiete ► Neurologie
• Themenwelt: Medizin / Pharmazie ► Pflege
• Themenwelt: Medizin / Pharmazie ► Physiotherapie / Ergotherapie ► Rehabilitation
• ISBN-10: 0-323-24234-0 / 0323242340
• ISBN-13: 978-0-323-24234-9 / 9780323242349