Multiple Sclerosis is a demyelization disorder of the central nervous system and the spinal cord; which leads to patches of plaques in the regions of the brain and spinal cord. (Stedman’s Medical Dictionary, 2000) There are many types of multiple sclerosis, however the severity and type of multiple sclerosis depends upon the size and location of the plaque.
Causes of multiple sclerosis may vary; however, research has linked many different causes to the onset of MS. Causes may include: a virus causing demyelization, violent trauma to the head or spinal cord, and or an immune system attack which cause the body to attack the myelin sheaths around the neurons in the ascending and descending pathways.
The most common symptoms and limitations for multiple sclerosis patients are fatigue, muscle weakness, difficulty walking, and loss of vision (Silverthorn, 1998). Patients may also experience stiffness and spacticity, balance and coordination impairment, bladder or bowel dysfunction, cognitive or emotional disturbances, or pain. Each individual may experience one or more symptoms sporadically, with temporary periods of remission (Whitney, 2001). Thus, limitations depend on the severity of the MS or if the MS is in remission or exacerbation state.
Since MS is a neurological disease, many limitations are caused by a lack of neuromuscular control. One limitation for MS patients is spacticity. Since the patient becomes more spastic and loses control of voluntary muscle, it becomes harder for them to control desired movement plans. Gait becomes a problem because the MS patient cannot always control the appropriate muscles needed to effectively and efficiently loco mote.
Efficiency of movement is also a limitation among patients with MS. Most MS patients become tired or weak due the amount of energy it takes to control muscle activity. Weakness is due to poor transmission of electrical impulse, thus server uphill locomotion may only fatigue the nerve and further increase the muscle weakness. However, Randall and Schapiro found that patients with MS who perform well balance exercises that involve weight lifting or repetitive movements of muscles to the point of fatigue do not increase their muscular strength. Rather they increase weakness and fatigue. (Randall & Schapiro, 1994)
Fatigue is another limitation for patients with MS because it makes it difficult to maintain proper workout intensity. Muscle fatigue leads to unproductive gait as well as putting the patient at a higher risk of injury due to the fact that fatigue often leads to nausea and disorientation. This in turn could lead the MS patient to even higher risk of injuring themselves because they are even less aware of there surrounding environment.
Another limitation for MS patients is muscle weakness. For many MS patients pain becomes a major issue as the condition begins to worsen. Thus, this causes muscle to weaken dramatically due to the fact that pain causes the patients to move less, and in turn leads to muscle atrophy. Since there is a decrease in muscle mass and strength the ability, gait also becomes altered.
In 1976, Baum and Rothschild found that 123,000 people were reportedly diagnosed with multiple sclerosis. Female were 1.7 times more likely than a male to be diagnosed, and a non-white person was half as likely to be diagnosed versus a white individual. Those living in areas considered as “high risk” were 1.9 times as likely to be diagnosed with the disease. “Prevalence rate by age rose sharply from the group below 20 years old to the 30-39 age groups, and then rapidly decreased for those 60 years and older (Baum and Rothschild, 1981).” More recently, from 1990 to 1992, the Centers for Disease Control and Prevention reported 180,000 new cases of MS, with 250,000 to 350,000 Americans living with the disease at that time. Women were stated to be three times more likely than men to get MS (Whitney, 2001). Over time it seems the prevalence of this disease has not increased sharply within the general population of Americans, although the likelihood of a female being diagnosed with the disease is increasing. This may be due to environmental or genetic risk factors.
Locomotion is the most basic and yet most essential part of a human transportation. The purpose of this paper is to focus on how Multiple Sclerosis effects gait pattern.
In a study by Goldfarb & Simon 1984, research was conducted for the purpose of looking at the relationship between Amyotrophic MS and walking performance. They studied 7 women and 17 men who were all within normal height/weight ranges (all subjects were within 15 pounds of a standard height weight table). This was used to rule out obesity. Subject’s ages ranged from 31-81 years.
Eight muscles were identified for either the swing phase or stance phase. Swing muscles were anterior tibialis, hamstrings, quadriceps and hip flexors; Stance muscles included the gastronomies, quadriceps, adductors, gluteus medius and gluteus maximums.
Goldfarb, et al found that patients with Amyotrophic MS spend less time in the swing phase and more time in stance phase. Therefore, walking velocity decreased in patients Amyotrophic MS. They also found there was no correlation between velocity of walking and the following: 1) the number of months since patient was diagnosed, 2) pulmonary function and 3) the type of neurological involvement (Goldfarb & Simon 1984).
Another study on MS looked at the effects of an aquatic exercise program on gait parameters. 11 patients with MS volunteered for the study but two quit before the final test. All subjects participated in a 10 week aquatic exercise program consisting of aqua-calisthenics and freestyle swimming. Three sixty minute exercise sessions were held each day and exercise intensity was 60% to 75% sub maximal (Gehlsen, et al 1986)
Results indicated patients with MS showed decrease in stride length, slower free speed walking rates and higher walking cadence than those patients without MS. They also found that patients with MS have less vertical lift when walking.. Thus, according to there research aquatic fitness programs have no major effect on improving or impairing studied gait parameters.
A study by Rodgers et al 1999 also looked at gait characteristic before and after a six month aerobic training program. 18 patients (14 female and 4 male) with different stages of MS were studied. The exercise program consisted of a cycle ergo-meter protocol in which the subjects exercised three times a week for 30 minutes maintaining a heart rate in and around 65 to 70% (Rodgers, et al 1999). The subjects used a combined arm/leg ergo-meter for a total of 24 weeks.
They found that there was an increase hip abduction/adduction and internal/external rotation indicating that a specific range of motion pattern was favorable due to exercise. They also found that patients with MS have an increase tightness of the hip flexors.
However, because of the nature of the disease they were only able concluded that because neurological decline from MS occurred within the 6 month time frame for several subjects, it was difficult to differentiate the effects of intervention by exercise, form changes in status resulting from progressive of the disease (Rodgers, et al 1999).
Frzovic, Morris & Vowels 2000 looked at standing balance performance in patients with MS. Twenty eight subjects were used, 14 with MS and 14 without MS (14 control subject matched for age, gender and height). In this study subjects were measured on their standing balance with feet apart, feet together, stride stance, double support stance, single support stance and self generated perturbations.
Results illustrated that there were no differences between MS and the MS control group on the ability to maintain standing balance with feet apart, feet together or in stride stance. Patients with MS performed more poorly than control subjects in double and single leg stance and in the functional reach test, arm test, step test and in response to external perturbation (Frzovic, Morris & Vowels, 2000)
Not only was research conducted on the effects of MS on exercise and balance. Research was also conducted on the effects of drugs on MS and its effect on gait parameter. Several forms of treatment for the symptoms and progression of MS are currently being researched. For example, low-dose oral methotrexate (MTX), human interferons (IFNs), and the drug cladribine have all been approved to treat MS. Use of oral methotrexate was studied by Goodkin, et al. (1995) in an attempt to find a drug less toxic than drugs copolymer 1 and interferon beta-1b. A study conducted by Orsnes, Sorensen, Larsen & Ravnborg 2000 looked at the effects of baclofen on gait. 14 patients aging from 24-57 were studied. The study was a placebo-controlled, double-blind cross-over study, all patients were either assigned to baclofen or placebo. Doses of 5mg 3 times a day were taken, after 11 days measurements were taken, followed by a two week wash out period. After which the seven placebo patients were given baclofen and seven baclofen patients were given the placebo.
Results revealed that there was no significant difference between baclofen and placebo treatment in postural and gait instability with open and closed eyes (Orsnes, Sorensen, Larsen & Ravnborg 2000). Thus, they concluded that the effects of baclofen on gait in treatment of spacticity was not evident in their study
MS is a severe demyelization disease that has numerous effects on the human body’s functional ability. In the research discussed it is evident that gait patterns in patients with MS are determined by the progression to the disease, rather then exercise and training. Research concluded that aerobic and aquatic training have little to no significance in the maintance of gait patterns in MS patients. Drug therapies have more side effects then benefits. For example, Orsnes, Sorensen, Larsen & Ravnborg 2000 found that nine patients reported side effects of fatigue dizziness, nausea, bad temper, diarrhea and more frequent urination. Also the study found that the drug had also little to no effect on maintance of gait patterns.
Furthermore, according to the research, destruction of myelin on the axons is thought to be due to the development of lesions in the central nervous system. Loss of myelin makes it difficult for people suffering from Multiple Sclerosis to perform control voluntary movement (gait). This is because the axon potentials that are transmitted from one neuron to another in a healthy individual are lacking the insulation of myelin, which then delays conduction.
Impaired walking ability in spastic patients is probably caused by decrease voluntary force in the dorsiflexor muscles, increased passive stiffness of the ankle joint and increased threshold of the stretch reflexes along with impaired modulation of the H-reflex (Sinkjaer, Anderson & Nielsen 1996)
It is clear that further research must be conducted in order to find a cure or a form of inhabiting the onset of MS. Discovery of a medication that treats all symptoms and slows the progression of the disease internally to improve movement function would be ideal. For many sufferers of MS, the disease goes into remission frequently. With a drug that treats the disease as a whole would allow patients to be able to live symptom free live as well maintain there normal gait pattern.