|Synonyms and related keywords: PPS|
History: Symptoms usually appear earlier in patients who have very severe residual weakness, early bulbar respiratory difficulty in the acute illness, and those who were older when they contracted acute polio. PPS symptoms tend to occur first in the weaker muscles.
- Fatigue: In individuals without polio or PPS, the functional consequences of aging and loss of motor units may be unnoticeable until a very advanced age. In the individual with PPS, any further loss of strength may be more readily apparent. In contrast to patients with chronic fatigue syndrome, postpolio fatigue is prominent in the early hours of the afternoon and decreases after brief periods of rest. PPS-related fatigue usually does not prevent patients from working.
- Pathogenesis can include chronic pain, type A personality, depression, dysfunctional reticular-activated system, sleep disorders, and respiratory dysfunction.
- PPS produces somnolence and difficulty in concentrating and remembering.
- Pathogenesis may be metabolic exhaustion of the enlarged motor units, neuromuscular junction transmission defects, scarring within the motor neurons, or loss of motor units due to aging.
- PPS produces decreased muscular endurance and increased muscular fatigability.
- A number of functional etiologies for weakness have been hypothesized, including disuse, overuse, and chronic weakness, as well as weight gain.
- Asymmetric and scattered weakness may be present.
- Some authors have found evidence that previously unaffected muscles later become weak; in these cases, they discovered that the patient was unaware or had not been told that the particular muscle had been affected during the acute episode.
- Muscle pain
- Deep aching pain may be a component of a myofascial pain syndrome or fibromyalgia.
- This feature is extremely prevalent in PPS.
- Gait disturbance: Difficulty with gait is caused by progressive weakness, pain, osteoarthritis, or joint instability; it is common in patients who previously used assistive devices but later discarded them.
- Respiratory problems
- Respiratory disorders are most prevalent in patients with residual respiratory muscle weakness.
- These changes cause chronic microatelectasis, diminished pulmonary compliance, increased chest wall tightness, chronic alveolar hypoventilation, decreased cough and expiratory flow, and decreased clearing of secretions.
- The new respiratory difficulties are not only related to new respiratory muscle weakness but also to scoliosis, pulmonary emphysema, cardiovascular insufficiency, or poor posture.
- A central component also may occur because acute bulbar polio often affects the medullary structures, including the reticular formation and sleep regulatory system.
- Swallowing problems
- These difficulties can occur in patients with bulbar and nonbulbar postpolio.
- Subclinical asymmetrical weakness in the pharyngeal constrictor muscles is almost always present in all postpolio muscular atrophy (PPMA) patients, including those who do not complain of new swallowing difficulties.
- Autonomic dysfunction: The cause is unclear; the peripheral component could include muscular atrophy and, therefore, diminished heat production.
- Sleep apnea
- This disorder is not uncommon in patients left with residual bulbar dysfunction or severe respiratory compromise.
- Sleep apnea appears to be due to a combination of the following:
- Central apnea, due to a residual dysfunction of the surviving bulbar reticular neurons
- Obstructive apnea, due to pharyngeal weakness and increased musculoskeletal deformities from scoliosis or emphysema
- PPMA, resulting in diminished muscle strength of the respiratory, intercostal, and abdominal muscle groups
- Flat back syndrome
- Another possible symptom in some patients with PPS is the flat back syndrome, which consists of the inability to stand erect because of forward flexion of the trunk and pain in the low back and legs.
- The flat back syndrome typically occurs in patients with diminished lumbar lordosis as a result of instrumentation of the spine for scoliosis, vertebral fracture, or degenerative joint disease.
- The trunk extensor musculature plays an essential role in maintaining upright posture, and it may be that PPS-related weakness in this musculature represents a major contributing factor to the flat back syndrome in these patients.
Physical: Progressive weakness and atrophy may be observed in muscles that were affected initially by the poliovirus or in muscles that were spared clinically, which tends to happen in an asymmetric distribution. Fasciculations sometimes can be observed in atrophic muscles, as a result of the lower motor neuron injury.
|Author: Flor M Muñiz, MD, Staff Physician, Department of Physical Medicine and Rehabilitation, Thomas Jefferson UniversityCoauthor(s): Gerald Herbison, MD, Clinical Professor, Department of Physical Medicine and Rehabilitation, Thomas Jefferson University|
|Flor M Muñiz, MD, is a member of the following medical societies: American Medical Association|
|Editor(s): Martin K Childers, DO, Associate Professor, Department of Physical Medicine and Rehabilitation, University of Missouri School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, Pharmacy, eMedicine; Kat Kolaski, MD, Adjunct Clinical Assistant Professor, Department of Pediatrics, University of North Carolina; Director, Pediatric and Adolescent Rehabilitation, Charlotte Institute of Rehabilitation; Kelly L Allen, MD, Consulting Staff, Department of Physical Medicine and Rehabilitation, Lourdes Regional Rehabilitation Center, Our Lady of Lourdes Medical Center; and Denise I Campagnolo, MD, MS, Clinical Director of Spinal Cord Injury Program, Associate Professor, Department of Physical Medicine and Rehabilitation, New Jersey Medical School|
Post Polio Litaff, Association A.C _APPLAC Mexico