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Poliomyelitis
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REVIEW PAPER
Poliomyelitis Part 1: An Old Problem Revisited Elizabeth Dean Mu bina Agboatwalla Maruke Dallimore Zehra Habib Du re-Samin A k ram
Over the past decade, interest in poliomyelitis has re-emerged in industrialised countries with the recognition that survivors of the disease are at risk of developing late sequelae including fatigue, weakness, pain, and reduced endurance which can significantly impair an individual's ability to function in daily life. Research and clinical investigation of the late sequelae of poliomyelitis Key Words Poliomyelitis, pathophysiology, late sequelae, multisystem and the natural history of the disease have assessment. nutrition, poliomyelitis clinic, sociocultural factors. provided insight into those components of the early management of poliomyelitis that were beneficial Summery and those which may have been detrimental. This Although poliomyelitis continues to be the major crippling disease article (part 1 of a two-part series) describes the of children globally, protocols for its management have not been significantly updated since the disease was eradicated in the pathophysiology of acute poliomyelitis and the industrialisedworld in the early 1960s. An understanding of the late sequelae of the disease. An understanding pathophysiology of poliomyelitis and its late sequelae (part 1). of the pathophysiology of poliomyelitis and its in conjunction with contemporary principles of rehabilitation practice, provides a basis for revising the principles of acute late sequelae provides a basis for revising its management of this disease. assessment (part 1)and early management (part 2). A detailed multisystem assessment is the basis for the treatment prescription. This assessment includes evaluation of the child's The goal of the World Health Organisation and growth and development and nutritional status, given that the Rotary International to eradicate poliomyelitisby majority of children who contract poliomyelitis live in developing the year 2000 may be optimistic based on the countries where malnutrition is prevalent. Finally, we provide some guidelines for developing a poliomyelitis clinic based on prevalence of poliomyelitis in developing countries minimal resources. Sociocultural factors musl be considered and and the problems associated with the widespread integrated into programme planning, however, because the dissemination of immunization programmes. successof the programme will rest, in large part, on the sensitivity Although prevention of and education about of the facility and its staff to such factors. poliomyelitis continue to be high priorities, the health care delivery systems, in developing countries in particular, need to consider how best to manage children who will be affected by poliomyelitis in the foreseeable future as well as those children who are currently affected. The two articles in this series are directed towards physical therapists in developing as well as industrialised countries. We hope to sensitise not only therapists in industrialised countries to the multiple challenges of practising in the developing world generally, and specifically in Introduction relation to the management of poliomyelitis, Although poliomyelitis has been effectively but to the management of poliomyelitis in the eradicated in the industralised world since the growing numbers of children and adults who 1950s and early 60s with the advent of the Salk have emigrated from developing to industrialised and Sabin vaccines (Center for Disease Control, countries. Sporadic outbreaks of poliomyelitis 1975), this disease and its disabling residua in the industrialised world have occurred since continue to be prevalent in developing countries. the epidemic. These outbreaks usually occur in Furthermore, small outbreaks in industrialised sectarian groups who do not wish to have their countries continue to occur periodically (Price and children immunised on religious grounds. There Plum, 1978).AJthough the total number of persons is grave concern, however, by health care workers, affected is less than ten annually in North America that this trend will place an increasing number (Fischer, 19851,outbreaks of epidemic proportions of children at risk. Finally, we propose that may recur in industrialised countries without this information will be beneficial to physical constant education, and surveillance and vigilance therapists involved with the management of through immunisation programmes. other disabling neuromuscular conditions.
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Pathophysiology of Poliomyelitis Acute Poliomyelitis Acute poliomyelitis is contracted through an enterovirus that accesses the body orofaecally (Jubelt and Lipton, 1989; Paul, 1971). There are three antigenically distinct viruses responsible for the disease (Bodian, 1962). These viruses incubate in the oropharynx and the gastrointestinal system for seven to ten days. If the viruses access the circulatory system and a viraemia results, the central nervous system is exposed to infection. The virus targets the anterior motor horn cells of the spinal cord primarily in the thoracic and lumbar regions. Less commonly, the virus attacks the respiratory centres of the midbrain, the cranial nerves, and the intermediolateral columns of the spinal cord which control sympathetic nervous system function. Depending on the site of involvement, there are three primary presentations: spinal. bulbar and encephalitic or some combination of these (Price and Plum, 1978). The presence and temporal occurrence of neuronal inflammation is variable in that, in some caees, nerve cell destruction may precede inflammation whereas in other cases inflammation may be virtually absent (Bodian, 1972). Spinal involvement is the most common type followed by a relatively small proportion of patients with bulbar involvement. The least common presentation is the encephalitic form. The early clinical presentation ia variable and often includes one or more of the following signs and symptoms: headache, irritability, malaise, fever, stiffness, muscle pain, paresis in one or more limbs, inability to roll, stand or walk, and breathing and swallowing problems.
The epidemiology of the disease differs in various parts of the world and possibly in different epochs (Fischer, 1985). In the industrialised countries, where sanitation standards were high during the epidemic, children may have succumbed because of their lack of natural immunity compared with children in the developing world where poliomyelitis is endemic and small outbreaks occur-seasonally. Endemic poliomyelitis which tends to occur in developing countries affects children mainly under the age of five (Horstmann, 1963) whereas in areas of epidemic poliomyelitis the peak age rises to 5 to 14 years with paralysis also occurring in some young adults. The older the child is on contracting the poliovirus, the greater degree of paralysis. Severel antecedent events were associated with the onset of poliomyelitis during the Western epidemic including heavy exertion, trauma, pregnancy, and surgery (Price and Plum, 1978; Klingman et al, 1988). Genetic susceptibility has also been proposed as a risk factor (Price and Plum, 1978), however, whether this reflects the
ph-lapy,
January 1995, vol81, M) 1
fact that family members were in closer proximity to an infected individual is unclear. The few cases of poliomyelitis that are reported annually in North America (Center for Disease Control, 1975; Price and Plum, 1978) include nonvaccinated immigrants, those who object to vaccinations on religious grounds, and child caregivers who contract poliomyelitis from an infant recently immunised with live vaccine. In developing countries, poliomyelitis may be contracted due to not being vaccinated, or being partially immunised (ie a child has not completed the immunisation schedule), or from receiving inadequately stored vaccine. Recovery from poliomyelitisis usually considerable with respect to functional return (Dean, 1991). Mortality usually multe from bulbar involvement from which children tend to recover better than adolescents and adults (Price and Plum, 1978). Prior to the vaccines, mortality rates declined in the industrialised world as a result of improved medical management of the disease and its complications.
Chronic Poliomyelitis and Late Sequelae Over the past 15 years in the industrialid countries there have been increasing reports of new problems in individuals with a history of poliomyelitis (Bruno, 1985; Cashman et ul, 1987; Frustace, 1988; Raymond, 1986; Wiechera, 1987). After some thirty to forty years of stable functioning, poliomyelitis survivora are reporting new symptoms including fatigue, weakness and pain in limbs previously not thought to have been affected as well as those that were affected,reduced endurance, increased difficulty with breathing and swallowing, increased sensitivity to cold, and psychological problems. The onset of these new problems has been reported to be related to the number of years after the initial onset of poliomyelitis, the severity of the disease initially, older age at onset, and a rapid initial recovery (Halstead and Rossi, 1985). Estimates of the number of individuals affected by the late sequelae of poliomyelitis range from 20% to 80% (Halstead and WiGhers, 1985; Holman, 1986; Olsen and Henig, 1981). Several hypotheses for these late sequelae have been proposed including overwork of both affected and non-affected muscles, new denervation, muscle atrophy, impaired neuromuscular transmission, axonal degeneration, increased wear and tear on muscles and joints, biomechanical strain, impaired movement economy (ie an increased energy cost to walk), and cardiopulmonary deconditioning (Cashman et al, 1987; Dean and Ross, 1993; Peach, 1990). More recently there have been reports of immunological changes in patients with the late sequelae of poliomyelitis (Ginsberg et al, 1989). It has
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not been substantiated that the poliomyelitis has been reactivated in some way. The natural course of poliomyelitis h a s become better understood with the documentation of these late effects. Estimating the incidence of the late sequelae of poliomyelitis in developing countries has been hampered by the general lack of recognition of these symptoms, although these have only been apparent relatively recently in the industrialised countries. Poliomyelitis survivors may in fact differ between industrialised and developing countries. First, there are no statistics available to compare the incidence of spinal, bulbar, and encephalitic types of disease between the developing and industralised countries. In the industralised countries, many children who were severely affected survived due to medical advances compared with those in developing countries who may never have received medical attention, and if they did, life preserving facilities might have been unavailable. Thus, children who have survived poliomyelitis in developing countries may represent a biologically hardier cohort. Second, given the shorter life expectancy in developing countries, the late sequelae of the disease may not be manifested. As life expectancy increases globally, however, these effects will become more prevalent. Finally, as the late sequelae of poliomyelitis become publicised in developing countries, detection and intervention will be improved.
Management of Acute Poliomyelitis During the Epidemic Management of acute poliomyelitis i n industrialised countries during the epidemic in the middle of this century was based largely on the methods of Sister Kenny. They included routine heat treatments, stretching, and muscle reeducation (Cole et al, 1942; Pohl and Kenny, 1943). Despite the harsh criticism of these methods by the American Medical Association in 1944 (Ghormley and Compere, 19441,their use persisted throughout the industralised world through the epidemic years, and continue to prevail in the management of poliomyelitis in developing countries up to the present time. The major criticisms of Sister Kenny’s methods were the absence of any physiologic or scientific basis, and that they were administered routinely rather based on an assessment which was actively discouraged. Lack of improvement was attributed to caregivers not carrying out home treatments adequately (Ghormley and Compere, 1944). Although Sister Kenny denounced t h e use of mechanical ventilatory assistance (Cole et al, 1942), this tenet, fortunately, did not appear to have been stringently followed.
Basis for Revised and Updated Management Research and clinical reports in the literature related to the early management of poliomyelitis declined exponentially after the introduction of the vaccines and the eradication of the disease in the industrialised world. Nonetheless, important information can be gleaned from the current pathophysiologic understanding of the disease, and the knowledge that has accrued in recent years on chronic poliomyelitis and its late sequelae. This physiologic and scientific knowledge base, in conjunction with contemporary principles of rehabilitation practice, provides a framework for revising and updating the management of early poliomyelitis. Thus, in part 2 on ‘Revised Principles of Management’, the recommendations based on this framework are designed to exploit the strengths and minimise the potentially deleterious effects of the traditional methods of treating poliomyelitis. Revising the assessment and management of acute poliomyelitis based on current understanding of the pathophysiology of the disease and its late sequelae will help to minimise its residual effects in both the short and long term.
Assessment Differential Diagnosis The diagnosis of poliomyelitis is based primarily on the history and clinical presentation, and can be confirmed with a spinal tap or analysis of a stool specimen (Wilson et al, 1991). Poliomyelitis survivors in Western industralised countries 0 t h identify a ‘polio’ leg or arm.However, this can be a n unreliable indicator of the absence of signs of poliomyelitis in other limbs (Dean, 1991). Muscle groups previously not believed to be affected may show signs some three decades later (Dalakas, 1988). Similarly, ventilatory problems can be manifested years later even though respiratory involvement was not detected at onset (Dean et a?, 1991). In addition, there have been reports of misdiagnosis of other conditions during the epidemic. In developing countries, a high proportion of children fail to be diagnosed or are misdiagnosed (WHO, 1989a). A definitive diagnosis and detailed assessment are essential for optimal management. Accurate detection and diagnosis of poliomyelitis is a major problem in developing countries. This has not been facilitated by the definition for a case of poliomyelitis disseminated by the World Health Organisation (WHO, 1989b). A caSe of poliomyelitis is defined a s any patient with acute flaccid paralysis (including any child under 15years of age diagnosed to have Guillain-Bme syndrome) for whom no other cause can be ident-
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of the patient’s stage of recovery (Dean, 1991). The physical examination needs to include an examination of the head, neck and coughing and swallowing mechanisms, respiratory status and respiratory muscles (including the diaphragm, muscles of the chest wall and abdomen),chest wall, spinal alignment, cardiovascular, gastro-intestinal, genito-urinary and immunological systems, and Electrodiagnosis may have a more important role nutritional status. than has previously been recognised in assessment of poliomyelitis. Nerve conduction studies, for In addition to the Possible Primary effects Of example, can establish whether a muscle is POliOmyelitiS On cardiopulmonary function, the and Of neuromuScular and denervated, innervated or has components of both (Bournan and Shaffer, 1957). m i s is important musculoskeletal involvement may have a direct diagnostic information in the acute stage of the effect on cardiopulmonary status (Dean and Ross, disease. It also provides a physiologic basis for 1993, 1989; Waters et al, 1978). For example, cost of treatment and indices of physiologic recovery of the movement economy (eg the muscle and of treatment response Over time. ~f a walking) and cardiorespiratory conditioning muscle is totally denervaM, eledri-1 stimulation are important components Of function that are may have a role in maintaining tissue viability not often considered in patients with either acute until re-innervation OCCmS (Spielholz, 1987; or chronic neuromuscular dysfunction. Impaired Cummings, 1992). If there is no sign of re- movement economy a n d cardiorespiratory innemation within ten months, the probability deconditioning, however, contribute to fatigue, of it ever happening is considerably diminished weakness and pain and thereby can significantly (Reynolds, 1959). impair function. Thus, these components of movement energetics need to be assessed in both In the assessment Of PoliomYelitis, the short and long term as they can provide a electromyography has a role in differentiating rationalbasis for management. innervated and denervated muscle, and in establishing the rate and degree of muscle recovery (Cashman et al, 1987). In the assessment of post Facilitiesfor a Poliomyelitis Clinic poliomyelitis muscular atrophy in the chronic Poliomyelitis clinics require relatively few stages of the disease, the role of electromyography resources. An area that is physically safe is needed has been reported to be limited in that old in which various types of active exercise can be and new denervation cannot be distinguished encouraged. (Cashman et al, 1987). Given that one of the most justifiable treatments Neuromuscular and Musculoskeletal for post-acute paralytic poliomyelitis in young children is active exercise, commensurate with Assessments Physically examining infants and children with each child’s stage of neurodevelopment and poliomyelitis presents a unique challenge to maturation, a clinic needs to be equipped with the clinician. Conventional neuromuscular and mats, treatment tables, adjustable Parallel musculoskeletal examinations are hampered bars with a horizontal walkway, bolsters, balls, because they often rely on patient co-operation. a climbing f r a m e and cycling apparatus. Furthermore, malnourishment and developmental Hydrotherapy is a valuable therapeutic adjunct, delay may obscure the clinical presentation of but this may be impractical if the hygiene of a pool poliomyelitis in a significant propohion of children and patients is difficult to maintain. Air-inflatable in developing countries. Thus, on-going assessment splints can help to determine whether a n orthosis of nutritional status is essential. In the indust- would be beneficial before having one made. rialised countries, developmental milestones Splinting materials and personnel to make and have a n important role in monitoring growth fit orthoses will demand a significant proportion and development, and helping to establish the of the resources of the clinic. Finally, running contribution of these factors to treatment outcome. water and disinfectant are required to clean Such norms are often unavailable for children in equipment and minimise the spread of infection. developing countries. Furthermore, because of With imagination, the decor of a prevalent malnutrition, their use may be limited. rehabilitation facility can be enhanced with the use of bright colours, toys, puppets, music, pictures, Multi-system Assessment jumping harnesses, and apparatus that turns, spins Poliomyelitis has multi-system consequences in and rolls which can be used for both sensoly and addition to its neuromuscular and musculoskeletal motor stimulation and integration. Because many effects and these should be examined regardless children will attend the clinic for many weeks and
ified. Even in the absence of objective laboratory tests, a more rigorous diagnostic description of acute poliomyelitis would enhance detection and appropriate management of the disease and improve statistics on the prevalence of poliomyelitis globally. Electrodiagnosis
Phyaiothenpy,January 1995. vol81, no 1
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often months, the arrangement of the sensory stimuli should be changed frequently to minimise habituation. The treatment modalities need to be modifiable so they can be used to promote active exercise in a n atmosphere of fun and play.
Sociocultural Factors Related to Prevention and Treatment Efficacy Sociocultural norms, attitudes and education significantly influence the effectiveness of prevention and treatment programmes related to poliomyelitis. In order for prevention programmes to be successful in developing countries, several conditions are necessary. The child's caregiver needs to be aware of the importance of vaccination and the necessity of adhering to the child's immunisation schedule. I n addition, t h e probability of adequate immunisation is increased ifthe family lives within proximity of a health care centre that disseminates the vaccine, assures its potency and administers it during the maximal potency period. A significant proportion of children contract poliomyelitis with only partial immunity to the disease. Although some families may live within reach of a health care clinic, the demands on the family's resources to take one member away from the family to escort one child may not be feasible either for vaccinations or for a prolonged course of therapy. Transport costs may also discourage families. Thus, community-based health care centres are integral to instituting effective treatment a s well a s prevention programmes for poliomyelitis.
'ecovery, and teaching the caregiver about xeatment progression. The caregiver practises xogressing treatment under supervision and with appropriate feedback from the physical therapist. I'reatment parameters are discussed with the :aregiver to help ensure that they are performed appropriately. In this way, the caregiver is actively involved in the short-and long-term rehabilitation goals for the child while the therapist is able to devote more time to other children. Attitudes prevail in some developing countries that can impact adversely on health care delivery. For example, attitudes towards female children can result in girls being less well nourished and receiving poorer health care than boys. Negative attitudes may also prevail regarding disability. Some societies believe that impairment is retribution for wrong-doing or Kharmic law. In developing countries, individuals with disabilities have fewer available resources and opportunities and so are often neglected, have minimal access to health care, and resort to begging with the risk of being exploited on the streets.
Grass-roots groups can be used to disseminate h e a l t h promotion information throughout communities in developing countries. Such groups have been established in the Karachi area by two of the authors (Drs Agboatwalla and Akram). Their function has primarily been to educate women to talk to other women about maternal and child care, health and nutrition, hygiene and sanitation, food preparation and diarrhoea prevention. In addition, this communication system can be used to inform parents about the importance of immunisation Illiteracy rates are high in developing countries, and reinforce the importance of the detection and particularly for women who are the primary treatment of poliomyelitis. child caregivers. Educational information regarding prevention of poliomyelitis, its In developing countries, certain attitudes prevail recognition and management therefore may not be related to the expectations of patients and accessed by the child's caregiver, so that other clinicians toward the provision of health care. means of disseminating such information are There has been a n increasing trend in the West required. In addition, numerous dialects often over the past 25 years towards patients taking a n prevail within even small regions, thus the health active role in health maintenance and recovery carer facilities need to consider provision of from illness with less emphasis on being merely interpreters for the various dialects spoken in their passive recipients of care. This trend is less areas. Communication between clinicians and prevalent in developing countries where passive patients and their caregivers is crucial in providing treatments, eg the use of modalities, drugs or effective treatment for poliomyelitis and related surgery, are often favoured by patients and problems such as nutritional deficits, hygiene and their families. In this social context, the clinician sanitation, general infant health, co-operation with is inclined to respond to their expectation. home treatments and following a child's progress. Unlike some other areas of medicine, however, rehabilitation demands active involvement and The greater part of therapy needs to be carried out participation of the patient and family to maximise at home. Even three or four visits weekly to a long-term functional gain and independence. Thus, poliomyelitis clinic are not likely to be as effective education of the caregiver of a child with polioa s several short sessions daily administered at myelitis is essential from the outset to promote home by the child's caregiver. Visits to a active involvement with and commitment to the poliomyelitis clinic should focus on reassessment rehabilitation programme. Education of all types of the child, recording physical changes and of health care workers in developing countries
Phy8iotherapy,January 1995, vol61, no 1
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about the importance of rehabilitation is also Based on the pathophysiology of poliomyelitis and its late sequelae, several conclusions can be drawn necessarv. that will augment treatment efficacy and Means of elevating the status of disabled persons maximise functional independence over the life in developing countries in the context of the family cycle. A definitive differential diagnosis is and society are challanges that need to be essential. The overall assessment needs to include addressed by cross-cultural social scientists. This a precise description of those muscle groups that is one way that better health care and treatment are affected and the severity. The systemic effects of people with disabilities, and their integration of the disease need to be evaluated as part of a into society in these countries could be achieved. multisystem assessment; and given the problems with nutrition in the developing world, a Conclusions nutritional assessment needs to be included. Despite the efficacy of the poliomyelitis vaccine, Because growth and maturation will influence the current problems with its distribution, storage and clinical presentation and course of recovery, administration and social obstacles may hinder the clinicians need a thorough understanding of eradication of the disease by the year 2000 as normal growth and development and the impact decreed by the World Health Organisation. From of malnutrition on such development. Electroall indications, poliomyelitis will continue to be diagnostic procedures are the only means of rampant in many developing countries for more ascertaining whether muscle is denervated, and than another decade, and small outbreaks will of monitoring changes in muscle re-innervation continue to occur periodically in industrialised with recovery and treatment. The following article countries. This projection, coupled with the fact addresses treatment - which needs to be directed that many children and adults are d i c t e d with at each child's specific problems, prioritised the disease world-wide,demands that principles for according to the patient's needs, and judiciously the management of poliomyelitis be revised and timed with expected spontaneous recovery to updated 80 that treatment is physiologically based maximise functional return and independence in and the strengths of time-honoured practices are the short and long term. while effects Acknowledgments, authors' details and combined references are minimised. given after the second article in this series.
REVIEW PAPER
Poliomyelitis Part 2: Revised Principles of Management Elizabeth Dean Mubina Agboatwalla Mamke Dall imore Zehra Habib Du re-Samin A kram
Key Wonls Poliomyelitis, management, rest, deformity prevention, active exercise, electrical stimulation, orthoses.
Summary An understandingof the pathophysiology of poliomyelitis and its late sequelae (part 1) in conjunction with contemporary principles of rehabilitation practice, provides a basis for revising the principles for acute management to optimise function over the long term. This article outlines such a revised basis for treatment of early poliomyelitis. First, treatment is based on a definitive diagnosis and multi-system assessment given the systemic effects of the disease (part 1). A nutritional assessment is also essential in developing countries
Phyrbthempy, January 1995, vol81, no 1
where this disease is prevalent. Treatment should be implemented early and continued throughout the first year after onset when most recovery is likely to occur. Rest, comfort, and the prevention of deformity with proper body positioning and range of motion exercise remain Driorities. In the post-acute stage, however, the routine procedures outlined by Sister Kenny that dominated management in the epidemic in the industrialisedcountries should be replaced with prescriptive physiologically-based treatment. Heat may reduce pain, spasm and stiffness, and optimise the effect of range of motion exercise. Exercise needs to be prescribed in such a wav that over-exertion, fatigue, pain and further muscle damage are minimised. Dynamic moderate resistive exercise can be supported for strength and endurance training. Heavy resistive exercise may contribute to muscle irritation, pain and muscle damage. The frequency. duration and time course of treatment are based on the assessment. We conclude that the revision of management of poliomyelitis based on an understanding of its pathophysiology and the late sequelae will promote long-term function and minimise the demands of these patients on the health care delivery system over time.
REVIEW PAPER
Poliomyelitis Part 1: An Old Problem Revisited Elizabeth Dean Mu bina Agboatwalla Maruke Dallimore Zehra Habib Du re-Samin A k ram
Over the past decade, interest in poliomyelitis has re-emerged in industrialised countries with the recognition that survivors of the disease are at risk of developing late sequelae including fatigue, weakness, pain, and reduced endurance which can significantly impair an individual's ability to function in daily life. Research and clinical investigation of the late sequelae of poliomyelitis Key Words Poliomyelitis, pathophysiology, late sequelae, multisystem and the natural history of the disease have assessment. nutrition, poliomyelitis clinic, sociocultural factors. provided insight into those components of the early management of poliomyelitis that were beneficial Summery and those which may have been detrimental. This Although poliomyelitis continues to be the major crippling disease article (part 1 of a two-part series) describes the of children globally, protocols for its management have not been significantly updated since the disease was eradicated in the pathophysiology of acute poliomyelitis and the industrialisedworld in the early 1960s. An understanding of the late sequelae of the disease. An understanding pathophysiology of poliomyelitis and its late sequelae (part 1). of the pathophysiology of poliomyelitis and its in conjunction with contemporary principles of rehabilitation practice, provides a basis for revising the principles of acute late sequelae provides a basis for revising its management of this disease. assessment (part 1)and early management (part 2). A detailed multisystem assessment is the basis for the treatment prescription. This assessment includes evaluation of the child's The goal of the World Health Organisation and growth and development and nutritional status, given that the Rotary International to eradicate poliomyelitisby majority of children who contract poliomyelitis live in developing the year 2000 may be optimistic based on the countries where malnutrition is prevalent. Finally, we provide some guidelines for developing a poliomyelitis clinic based on prevalence of poliomyelitis in developing countries minimal resources. Sociocultural factors musl be considered and and the problems associated with the widespread integrated into programme planning, however, because the dissemination of immunization programmes. successof the programme will rest, in large part, on the sensitivity Although prevention of and education about of the facility and its staff to such factors. poliomyelitis continue to be high priorities, the health care delivery systems, in developing countries in particular, need to consider how best to manage children who will be affected by poliomyelitis in the foreseeable future as well as those children who are currently affected. The two articles in this series are directed towards physical therapists in developing as well as industrialised countries. We hope to sensitise not only therapists in industrialised countries to the multiple challenges of practising in the developing world generally, and specifically in Introduction relation to the management of poliomyelitis, Although poliomyelitis has been effectively but to the management of poliomyelitis in the eradicated in the industralised world since the growing numbers of children and adults who 1950s and early 60s with the advent of the Salk have emigrated from developing to industrialised and Sabin vaccines (Center for Disease Control, countries. Sporadic outbreaks of poliomyelitis 1975), this disease and its disabling residua in the industrialised world have occurred since continue to be prevalent in developing countries. the epidemic. These outbreaks usually occur in Furthermore, small outbreaks in industrialised sectarian groups who do not wish to have their countries continue to occur periodically (Price and children immunised on religious grounds. There Plum, 1978).AJthough the total number of persons is grave concern, however, by health care workers, affected is less than ten annually in North America that this trend will place an increasing number (Fischer, 19851,outbreaks of epidemic proportions of children at risk. Finally, we propose that may recur in industrialised countries without this information will be beneficial to physical constant education, and surveillance and vigilance therapists involved with the management of through immunisation programmes. other disabling neuromuscular conditions.
18
Pathophysiology of Poliomyelitis Acute Poliomyelitis Acute poliomyelitis is contracted through an enterovirus that accesses the body orofaecally (Jubelt and Lipton, 1989; Paul, 1971). There are three antigenically distinct viruses responsible for the disease (Bodian, 1962). These viruses incubate in the oropharynx and the gastrointestinal system for seven to ten days. If the viruses access the circulatory system and a viraemia results, the central nervous system is exposed to infection. The virus targets the anterior motor horn cells of the spinal cord primarily in the thoracic and lumbar regions. Less commonly, the virus attacks the respiratory centres of the midbrain, the cranial nerves, and the intermediolateral columns of the spinal cord which control sympathetic nervous system function. Depending on the site of involvement, there are three primary presentations: spinal. bulbar and encephalitic or some combination of these (Price and Plum, 1978). The presence and temporal occurrence of neuronal inflammation is variable in that, in some caees, nerve cell destruction may precede inflammation whereas in other cases inflammation may be virtually absent (Bodian, 1972). Spinal involvement is the most common type followed by a relatively small proportion of patients with bulbar involvement. The least common presentation is the encephalitic form. The early clinical presentation ia variable and often includes one or more of the following signs and symptoms: headache, irritability, malaise, fever, stiffness, muscle pain, paresis in one or more limbs, inability to roll, stand or walk, and breathing and swallowing problems.
The epidemiology of the disease differs in various parts of the world and possibly in different epochs (Fischer, 1985). In the industrialised countries, where sanitation standards were high during the epidemic, children may have succumbed because of their lack of natural immunity compared with children in the developing world where poliomyelitis is endemic and small outbreaks occur-seasonally. Endemic poliomyelitis which tends to occur in developing countries affects children mainly under the age of five (Horstmann, 1963) whereas in areas of epidemic poliomyelitis the peak age rises to 5 to 14 years with paralysis also occurring in some young adults. The older the child is on contracting the poliovirus, the greater degree of paralysis. Severel antecedent events were associated with the onset of poliomyelitis during the Western epidemic including heavy exertion, trauma, pregnancy, and surgery (Price and Plum, 1978; Klingman et al, 1988). Genetic susceptibility has also been proposed as a risk factor (Price and Plum, 1978), however, whether this reflects the
ph-lapy,
January 1995, vol81, M) 1
fact that family members were in closer proximity to an infected individual is unclear. The few cases of poliomyelitis that are reported annually in North America (Center for Disease Control, 1975; Price and Plum, 1978) include nonvaccinated immigrants, those who object to vaccinations on religious grounds, and child caregivers who contract poliomyelitis from an infant recently immunised with live vaccine. In developing countries, poliomyelitis may be contracted due to not being vaccinated, or being partially immunised (ie a child has not completed the immunisation schedule), or from receiving inadequately stored vaccine. Recovery from poliomyelitisis usually considerable with respect to functional return (Dean, 1991). Mortality usually multe from bulbar involvement from which children tend to recover better than adolescents and adults (Price and Plum, 1978). Prior to the vaccines, mortality rates declined in the industrialised world as a result of improved medical management of the disease and its complications.
Chronic Poliomyelitis and Late Sequelae Over the past 15 years in the industrialid countries there have been increasing reports of new problems in individuals with a history of poliomyelitis (Bruno, 1985; Cashman et ul, 1987; Frustace, 1988; Raymond, 1986; Wiechera, 1987). After some thirty to forty years of stable functioning, poliomyelitis survivora are reporting new symptoms including fatigue, weakness and pain in limbs previously not thought to have been affected as well as those that were affected,reduced endurance, increased difficulty with breathing and swallowing, increased sensitivity to cold, and psychological problems. The onset of these new problems has been reported to be related to the number of years after the initial onset of poliomyelitis, the severity of the disease initially, older age at onset, and a rapid initial recovery (Halstead and Rossi, 1985). Estimates of the number of individuals affected by the late sequelae of poliomyelitis range from 20% to 80% (Halstead and WiGhers, 1985; Holman, 1986; Olsen and Henig, 1981). Several hypotheses for these late sequelae have been proposed including overwork of both affected and non-affected muscles, new denervation, muscle atrophy, impaired neuromuscular transmission, axonal degeneration, increased wear and tear on muscles and joints, biomechanical strain, impaired movement economy (ie an increased energy cost to walk), and cardiopulmonary deconditioning (Cashman et al, 1987; Dean and Ross, 1993; Peach, 1990). More recently there have been reports of immunological changes in patients with the late sequelae of poliomyelitis (Ginsberg et al, 1989). It has
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not been substantiated that the poliomyelitis has been reactivated in some way. The natural course of poliomyelitis h a s become better understood with the documentation of these late effects. Estimating the incidence of the late sequelae of poliomyelitis in developing countries has been hampered by the general lack of recognition of these symptoms, although these have only been apparent relatively recently in the industrialised countries. Poliomyelitis survivors may in fact differ between industrialised and developing countries. First, there are no statistics available to compare the incidence of spinal, bulbar, and encephalitic types of disease between the developing and industralised countries. In the industralised countries, many children who were severely affected survived due to medical advances compared with those in developing countries who may never have received medical attention, and if they did, life preserving facilities might have been unavailable. Thus, children who have survived poliomyelitis in developing countries may represent a biologically hardier cohort. Second, given the shorter life expectancy in developing countries, the late sequelae of the disease may not be manifested. As life expectancy increases globally, however, these effects will become more prevalent. Finally, as the late sequelae of poliomyelitis become publicised in developing countries, detection and intervention will be improved.
Management of Acute Poliomyelitis During the Epidemic Management of acute poliomyelitis i n industrialised countries during the epidemic in the middle of this century was based largely on the methods of Sister Kenny. They included routine heat treatments, stretching, and muscle reeducation (Cole et al, 1942; Pohl and Kenny, 1943). Despite the harsh criticism of these methods by the American Medical Association in 1944 (Ghormley and Compere, 19441,their use persisted throughout the industralised world through the epidemic years, and continue to prevail in the management of poliomyelitis in developing countries up to the present time. The major criticisms of Sister Kenny’s methods were the absence of any physiologic or scientific basis, and that they were administered routinely rather based on an assessment which was actively discouraged. Lack of improvement was attributed to caregivers not carrying out home treatments adequately (Ghormley and Compere, 1944). Although Sister Kenny denounced t h e use of mechanical ventilatory assistance (Cole et al, 1942), this tenet, fortunately, did not appear to have been stringently followed.
Basis for Revised and Updated Management Research and clinical reports in the literature related to the early management of poliomyelitis declined exponentially after the introduction of the vaccines and the eradication of the disease in the industrialised world. Nonetheless, important information can be gleaned from the current pathophysiologic understanding of the disease, and the knowledge that has accrued in recent years on chronic poliomyelitis and its late sequelae. This physiologic and scientific knowledge base, in conjunction with contemporary principles of rehabilitation practice, provides a framework for revising and updating the management of early poliomyelitis. Thus, in part 2 on ‘Revised Principles of Management’, the recommendations based on this framework are designed to exploit the strengths and minimise the potentially deleterious effects of the traditional methods of treating poliomyelitis. Revising the assessment and management of acute poliomyelitis based on current understanding of the pathophysiology of the disease and its late sequelae will help to minimise its residual effects in both the short and long term.
Assessment Differential Diagnosis The diagnosis of poliomyelitis is based primarily on the history and clinical presentation, and can be confirmed with a spinal tap or analysis of a stool specimen (Wilson et al, 1991). Poliomyelitis survivors in Western industralised countries 0 t h identify a ‘polio’ leg or arm.However, this can be a n unreliable indicator of the absence of signs of poliomyelitis in other limbs (Dean, 1991). Muscle groups previously not believed to be affected may show signs some three decades later (Dalakas, 1988). Similarly, ventilatory problems can be manifested years later even though respiratory involvement was not detected at onset (Dean et a?, 1991). In addition, there have been reports of misdiagnosis of other conditions during the epidemic. In developing countries, a high proportion of children fail to be diagnosed or are misdiagnosed (WHO, 1989a). A definitive diagnosis and detailed assessment are essential for optimal management. Accurate detection and diagnosis of poliomyelitis is a major problem in developing countries. This has not been facilitated by the definition for a case of poliomyelitis disseminated by the World Health Organisation (WHO, 1989b). A caSe of poliomyelitis is defined a s any patient with acute flaccid paralysis (including any child under 15years of age diagnosed to have Guillain-Bme syndrome) for whom no other cause can be ident-
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of the patient’s stage of recovery (Dean, 1991). The physical examination needs to include an examination of the head, neck and coughing and swallowing mechanisms, respiratory status and respiratory muscles (including the diaphragm, muscles of the chest wall and abdomen),chest wall, spinal alignment, cardiovascular, gastro-intestinal, genito-urinary and immunological systems, and Electrodiagnosis may have a more important role nutritional status. than has previously been recognised in assessment of poliomyelitis. Nerve conduction studies, for In addition to the Possible Primary effects Of example, can establish whether a muscle is POliOmyelitiS On cardiopulmonary function, the and Of neuromuScular and denervated, innervated or has components of both (Bournan and Shaffer, 1957). m i s is important musculoskeletal involvement may have a direct diagnostic information in the acute stage of the effect on cardiopulmonary status (Dean and Ross, disease. It also provides a physiologic basis for 1993, 1989; Waters et al, 1978). For example, cost of treatment and indices of physiologic recovery of the movement economy (eg the muscle and of treatment response Over time. ~f a walking) and cardiorespiratory conditioning muscle is totally denervaM, eledri-1 stimulation are important components Of function that are may have a role in maintaining tissue viability not often considered in patients with either acute until re-innervation OCCmS (Spielholz, 1987; or chronic neuromuscular dysfunction. Impaired Cummings, 1992). If there is no sign of re- movement economy a n d cardiorespiratory innemation within ten months, the probability deconditioning, however, contribute to fatigue, of it ever happening is considerably diminished weakness and pain and thereby can significantly (Reynolds, 1959). impair function. Thus, these components of movement energetics need to be assessed in both In the assessment Of PoliomYelitis, the short and long term as they can provide a electromyography has a role in differentiating rationalbasis for management. innervated and denervated muscle, and in establishing the rate and degree of muscle recovery (Cashman et al, 1987). In the assessment of post Facilitiesfor a Poliomyelitis Clinic poliomyelitis muscular atrophy in the chronic Poliomyelitis clinics require relatively few stages of the disease, the role of electromyography resources. An area that is physically safe is needed has been reported to be limited in that old in which various types of active exercise can be and new denervation cannot be distinguished encouraged. (Cashman et al, 1987). Given that one of the most justifiable treatments Neuromuscular and Musculoskeletal for post-acute paralytic poliomyelitis in young children is active exercise, commensurate with Assessments Physically examining infants and children with each child’s stage of neurodevelopment and poliomyelitis presents a unique challenge to maturation, a clinic needs to be equipped with the clinician. Conventional neuromuscular and mats, treatment tables, adjustable Parallel musculoskeletal examinations are hampered bars with a horizontal walkway, bolsters, balls, because they often rely on patient co-operation. a climbing f r a m e and cycling apparatus. Furthermore, malnourishment and developmental Hydrotherapy is a valuable therapeutic adjunct, delay may obscure the clinical presentation of but this may be impractical if the hygiene of a pool poliomyelitis in a significant propohion of children and patients is difficult to maintain. Air-inflatable in developing countries. Thus, on-going assessment splints can help to determine whether a n orthosis of nutritional status is essential. In the indust- would be beneficial before having one made. rialised countries, developmental milestones Splinting materials and personnel to make and have a n important role in monitoring growth fit orthoses will demand a significant proportion and development, and helping to establish the of the resources of the clinic. Finally, running contribution of these factors to treatment outcome. water and disinfectant are required to clean Such norms are often unavailable for children in equipment and minimise the spread of infection. developing countries. Furthermore, because of With imagination, the decor of a prevalent malnutrition, their use may be limited. rehabilitation facility can be enhanced with the use of bright colours, toys, puppets, music, pictures, Multi-system Assessment jumping harnesses, and apparatus that turns, spins Poliomyelitis has multi-system consequences in and rolls which can be used for both sensoly and addition to its neuromuscular and musculoskeletal motor stimulation and integration. Because many effects and these should be examined regardless children will attend the clinic for many weeks and
ified. Even in the absence of objective laboratory tests, a more rigorous diagnostic description of acute poliomyelitis would enhance detection and appropriate management of the disease and improve statistics on the prevalence of poliomyelitis globally. Electrodiagnosis
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often months, the arrangement of the sensory stimuli should be changed frequently to minimise habituation. The treatment modalities need to be modifiable so they can be used to promote active exercise in a n atmosphere of fun and play.
Sociocultural Factors Related to Prevention and Treatment Efficacy Sociocultural norms, attitudes and education significantly influence the effectiveness of prevention and treatment programmes related to poliomyelitis. In order for prevention programmes to be successful in developing countries, several conditions are necessary. The child's caregiver needs to be aware of the importance of vaccination and the necessity of adhering to the child's immunisation schedule. I n addition, t h e probability of adequate immunisation is increased ifthe family lives within proximity of a health care centre that disseminates the vaccine, assures its potency and administers it during the maximal potency period. A significant proportion of children contract poliomyelitis with only partial immunity to the disease. Although some families may live within reach of a health care clinic, the demands on the family's resources to take one member away from the family to escort one child may not be feasible either for vaccinations or for a prolonged course of therapy. Transport costs may also discourage families. Thus, community-based health care centres are integral to instituting effective treatment a s well a s prevention programmes for poliomyelitis.
'ecovery, and teaching the caregiver about xeatment progression. The caregiver practises xogressing treatment under supervision and with appropriate feedback from the physical therapist. I'reatment parameters are discussed with the :aregiver to help ensure that they are performed appropriately. In this way, the caregiver is actively involved in the short-and long-term rehabilitation goals for the child while the therapist is able to devote more time to other children. Attitudes prevail in some developing countries that can impact adversely on health care delivery. For example, attitudes towards female children can result in girls being less well nourished and receiving poorer health care than boys. Negative attitudes may also prevail regarding disability. Some societies believe that impairment is retribution for wrong-doing or Kharmic law. In developing countries, individuals with disabilities have fewer available resources and opportunities and so are often neglected, have minimal access to health care, and resort to begging with the risk of being exploited on the streets.
Grass-roots groups can be used to disseminate h e a l t h promotion information throughout communities in developing countries. Such groups have been established in the Karachi area by two of the authors (Drs Agboatwalla and Akram). Their function has primarily been to educate women to talk to other women about maternal and child care, health and nutrition, hygiene and sanitation, food preparation and diarrhoea prevention. In addition, this communication system can be used to inform parents about the importance of immunisation Illiteracy rates are high in developing countries, and reinforce the importance of the detection and particularly for women who are the primary treatment of poliomyelitis. child caregivers. Educational information regarding prevention of poliomyelitis, its In developing countries, certain attitudes prevail recognition and management therefore may not be related to the expectations of patients and accessed by the child's caregiver, so that other clinicians toward the provision of health care. means of disseminating such information are There has been a n increasing trend in the West required. In addition, numerous dialects often over the past 25 years towards patients taking a n prevail within even small regions, thus the health active role in health maintenance and recovery carer facilities need to consider provision of from illness with less emphasis on being merely interpreters for the various dialects spoken in their passive recipients of care. This trend is less areas. Communication between clinicians and prevalent in developing countries where passive patients and their caregivers is crucial in providing treatments, eg the use of modalities, drugs or effective treatment for poliomyelitis and related surgery, are often favoured by patients and problems such as nutritional deficits, hygiene and their families. In this social context, the clinician sanitation, general infant health, co-operation with is inclined to respond to their expectation. home treatments and following a child's progress. Unlike some other areas of medicine, however, rehabilitation demands active involvement and The greater part of therapy needs to be carried out participation of the patient and family to maximise at home. Even three or four visits weekly to a long-term functional gain and independence. Thus, poliomyelitis clinic are not likely to be as effective education of the caregiver of a child with polioa s several short sessions daily administered at myelitis is essential from the outset to promote home by the child's caregiver. Visits to a active involvement with and commitment to the poliomyelitis clinic should focus on reassessment rehabilitation programme. Education of all types of the child, recording physical changes and of health care workers in developing countries
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about the importance of rehabilitation is also Based on the pathophysiology of poliomyelitis and its late sequelae, several conclusions can be drawn necessarv. that will augment treatment efficacy and Means of elevating the status of disabled persons maximise functional independence over the life in developing countries in the context of the family cycle. A definitive differential diagnosis is and society are challanges that need to be essential. The overall assessment needs to include addressed by cross-cultural social scientists. This a precise description of those muscle groups that is one way that better health care and treatment are affected and the severity. The systemic effects of people with disabilities, and their integration of the disease need to be evaluated as part of a into society in these countries could be achieved. multisystem assessment; and given the problems with nutrition in the developing world, a Conclusions nutritional assessment needs to be included. Despite the efficacy of the poliomyelitis vaccine, Because growth and maturation will influence the current problems with its distribution, storage and clinical presentation and course of recovery, administration and social obstacles may hinder the clinicians need a thorough understanding of eradication of the disease by the year 2000 as normal growth and development and the impact decreed by the World Health Organisation. From of malnutrition on such development. Electroall indications, poliomyelitis will continue to be diagnostic procedures are the only means of rampant in many developing countries for more ascertaining whether muscle is denervated, and than another decade, and small outbreaks will of monitoring changes in muscle re-innervation continue to occur periodically in industrialised with recovery and treatment. The following article countries. This projection, coupled with the fact addresses treatment - which needs to be directed that many children and adults are d i c t e d with at each child's specific problems, prioritised the disease world-wide,demands that principles for according to the patient's needs, and judiciously the management of poliomyelitis be revised and timed with expected spontaneous recovery to updated 80 that treatment is physiologically based maximise functional return and independence in and the strengths of time-honoured practices are the short and long term. while effects Acknowledgments, authors' details and combined references are minimised. given after the second article in this series.
REVIEW PAPER
Poliomyelitis Part 2: Revised Principles of Management Elizabeth Dean Mubina Agboatwalla Mamke Dall imore Zehra Habib Du re-Samin A kram
Key Wonls Poliomyelitis, management, rest, deformity prevention, active exercise, electrical stimulation, orthoses.
Summary An understandingof the pathophysiology of poliomyelitis and its late sequelae (part 1) in conjunction with contemporary principles of rehabilitation practice, provides a basis for revising the principles for acute management to optimise function over the long term. This article outlines such a revised basis for treatment of early poliomyelitis. First, treatment is based on a definitive diagnosis and multi-system assessment given the systemic effects of the disease (part 1). A nutritional assessment is also essential in developing countries
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where this disease is prevalent. Treatment should be implemented early and continued throughout the first year after onset when most recovery is likely to occur. Rest, comfort, and the prevention of deformity with proper body positioning and range of motion exercise remain Driorities. In the post-acute stage, however, the routine procedures outlined by Sister Kenny that dominated management in the epidemic in the industrialisedcountries should be replaced with prescriptive physiologically-based treatment. Heat may reduce pain, spasm and stiffness, and optimise the effect of range of motion exercise. Exercise needs to be prescribed in such a wav that over-exertion, fatigue, pain and further muscle damage are minimised. Dynamic moderate resistive exercise can be supported for strength and endurance training. Heavy resistive exercise may contribute to muscle irritation, pain and muscle damage. The frequency. duration and time course of treatment are based on the assessment. We conclude that the revision of management of poliomyelitis based on an understanding of its pathophysiology and the late sequelae will promote long-term function and minimise the demands of these patients on the health care delivery system over time.