Exercise programs for patients with post-polio syndrome: a case report.

Exercise Programs for Patients with Post-Polio Syndrome: A Case Report The development of increased muscular weakness years after the initial contraction of poliomyelitis was first documented as long ago as 1875 by Raymond and Charcot. [1] More than three decades have elapsed since epidemics of poliomyelitis were common in the United States. Data compiled from 1920 through 1987 by the Centers for Disease Control, Atlanta, Ga (unpublished data, April 1988), indicate that about 514,000 individuals have survived an initial episode of paralytic poliomyelitis in the United States. The literature contains many reports regarding the complaints of patients with post-polio syndrome, including diminutiong of muscle strength and endurance and loss of functional capabilities. Symptoms become evident about 30 years following the initial acute infection, regardless of the age of the patient at the time of poliomyelitis onset. [2,3 Reports have been published in the intervening years, which also describe this later onset of increased muscle weakness, and there has been much speculation regarding the mechanisms involved in this process. [3-9] There has been a dearth of published information, however, concerning the response of muscles weakened by poliomyelitis to exercise.

Herbison et al suggest that an isometric (static) or progressive resistance exercise program performed five to six times daily may increase muscle strength in these patients when the exercise program is initiated weeks to years after the onset of poliomyelitis. [10] Muller reported that the daily performance by children of 18-second maximal isometric contractions resulted in an increase of strength of muscles affected by poliomyelitis. [11] These results were observed when children with post-polio syndrome initiated the exercise regimen 6 to 15 years after the onset of poliomyelitis. Twist and Ma indicated that a combination of moderate exercise and rest improved the strength of a patient with post-polio syndrome, as assessed by manual muscle testing. [12] They suggest that "tough and exhaustive exercise" is inappropriate for those individuals experiending a decline in muscle strenght and endurance secondary to port-polio syndrome. Alsentzer states that his clinical experience suggests that "strengthening exercises add only short-lived, if any, strength and endurance" in patients with post-polio syndrome and may accelerate the development of weakness and loss of endurance. [13] No information is available regarding the effects of an intensive program of exercise for patients with post-polio syndrome. The purpose of this case report is to report the result of a specific isokinetic exercise regimen performed by a patient with post-polio syndrome.

History

The patient was a 59-year-old male who contracted poliomyelitis in 1944 at the age of 16 years, with an initial loss of all active movement in the left lower extremity. The Table indicates the left lower extremity muscle strength at the peak of recovery, three years after the onset of poliomyelitis. Passive range of motion was within normal limits at this time, and all other muscles not indicated in the Table were unaffected.

The patient did not use any orthosis and walked with a compensatory foot-drop pattern that was discernible to the acute observer. The patient resumed vigorous athletic activity between 1945 and 1948, including football, basketball, baseball, volleyball, and tennis. Although he was unable to run as quickly as he had before contracting poliomyelitis, his only complaint was difficulty in walking over irregular surfaces. The patient's pattern of physical activity since 1973 involved playing tennis three times weekly, in addition to a usual amount of walking and stair-climbing activities.

In 1978, at the age of 50 years, the patient noted some deterioration of muscle strength and endurance in the left lower extremity, with a noticeable effect on gait. He became more fatigued when walking lengthy distances, and there was an appreciable increase in the frequency of catching his toe on objects with the affected left leg. The patient began to use a polypropylene ankle-foot orthosis in 1980, primarily when he anticipated walks exceeding 0.25 mile (*1) or walks over irregular surfaces. The patient reported that the use of the AFO increased ankle stability and enabled him to ambulate at a more rapid rate with less expenditure of energy. The patient limited his use of the AFO because he feared becoming totally dependent on the orthosis.

In 1986, the patient noted a continued and somewhat more pronounced diminution of muscle strength and endurance. He, therefore, decided to wear the AFO more frequently. By mid-1987, the patient perceived a further decline in the strength and the endurance of the left hamstring muscle group, and occasionally developed cramping during recreational activities. The patient decided to attempt to increase his strength through a regular exercise program to prevent greater dependence on the AFO.

Method

The patient exercised three times a week for six weeks. He did not engage in any other exercise program and continued the pattern of daily activity previously described. We selected the knee flexor and extensor muscles for study because

1. The strength of the knee flexors and extensors could be quantified using an isokinetic device.

2. The patient was using the knee flexors as the primary muscle group to clear the foot during the swing phase of gait.

3. The strength of the knee flexors and extensors of our patient was comparable to the strength of the knee flexors and extensors of the patient tested by Twist and Ma. [12]

Knee flexion and extension torques were assessed before instituting the exercise program and then at 2, 4, and 6 weeks after the beginning of the program. Two additional tests were conducted at 6 and 22 weeks following the cessation of exercise. All exercise and testing was performed on the Cybex [R] II isokinetic dynamometer. (2) At each testing session, the patient also subjectively reported his muscle strength and endurance in performing functional activities.

We tested the affected and the unaffected legs of the patient at test velocities of 60[degrees] and 180[degrees]/sec at each of the six testing sessions. The order of affected-unaffected leg testing and the order of test speeds were randomized at each test session. The patient sat in the testing apparatus with hips and knees flexed at approximately 90 degrees. We stabilized the patient with thigh, pelvic, and chest straps. Before testing each leg, we performed procedures to correct all torque values for the effects of gravity acting on the mass of the lower leg and the mass of the Cybex[R] II dynamometer arm.[14]

The patient performed one practice series of five submaximal knee extension-flexion repetitions at the first test velocity to become familiar with the testing condition and to minimize any practice effect. After two minutes of rest, the patient performed three maximal knee extension-flexion efforts. After another two minutes of rest, the patient performed a second series of three maximal knee extension-flexion efforts. The examiner (MTG) recorded the peak knee extension torque value and the peak knee flexion torque value that occurred during either of the two data collection series. The investigators used an identical procedure for the second test velocity for the same lower extremity. The investigators then positioned the patient for the same testing protocol for the contralateral leg.

One of the authors (MTG) has evaluated the reliability of this testing protocol for another investigation (in progress). Six subjects were tested twice with the previously described protocol, with two days separating the testing sessions. Each subject provided an extension and a flexion peak torque measurement for each leg at both test velocities, for a total of eight observations per subject. The Pearson product-moment correlation coefficient for 48 repeated measurement of peak torque was .93, and the mean difference between repeated measurements was 6.1 ft.lb (*3) (s = 5.8).

For each exercise session, the patient performed knee flexion and extension exercises at 60[degrees] and 180[degress]/sec with each leg. Following the performance of a few submaximal extension-flextion efforts at 60[degrees] and 180[degress]/sec, the patient performed a set of 10 maximum extension-flexion efforst at 60[degree]/sec. The patient rested for about two minutes and then performed a second set of 10 repetitions at the same angular velocity. The identical protocol was used in performing two sets of 10 repetitions at 180[degrees]/sec for the same extremity and in performing two sets of 10 repetitions at each angular velocity for the contralateral leg. We considered this exercise program relatively more intensive than other reported exercise programs that have effected an increase in the muscle strength of healthy subjects. [15,16] The patient did not alter his normal daily activities either during the 6-week exercise program or during the 22-week period that followed the exervide program.

Results

The peak knee flexion and knee extension torques produced by the patient over the course of the six testing sessions are graphically represented in Figures 1 and 2. The patient subjectively reported that his muscle strength and endurance in performing functional activities decreased during the third week of the exercise program and improved during the last two weeks of the exercise program.

Discussion and Conclusions

The results of this case study do not support the conclusions of Twist and Ma [12] or Alsentzer. [13] Our patient did not demonstrate an appreciable decrease in the ability to exert torques either at the end of the vigorous 6-week exercise program or at 6 or 22 weeks following the cessation of the exercise program. Our patient, however, did not demonstrate what we consider an appreciable increase in the strength of muscles affected or unaffected by poliomyelitis. Twist and Ma did report a rather dramatic increase in the strength of a debilitated patient with post-polio syndrome following a more conservative exercise program. Their patient increased the strength of three out of four muscle groups by more than one muscle test grade. [12] Muller reported an increase in strength in the leg muscles of children with post-polio syndrome after they performed an isometric exercise program. [11]

Our case study and other studies concerned with exercise programs for patients with post-polio syndrome are dissimilar in several respects. The study by Muller involved a young patient population and an exercise program consisting of isometric muscle contractions. Muller used a strain gauge to assess muscle strength. [11] The patient in Twist and Ma's study [12] was ralatively more debilitated than our patient, and they used MMT to assess muscle strength. Twist and Ma used an exercise program consisting of isometric, isotonic (dynamic), and proprioceptive exercise set of 10 facilitation exercies. Their patient rested for three to five minutes between each exercise set of 10 reptitions. Our patient rested for one minute between each exercise set of 10 maximal isokinetic contractions. The results of our study indicated no deleterious effects from an intesive exercise program with a relatively active patient.

Future studies in this are should involve large numbers of subjects, and the research design should control for initial differences in muscle strength and age among subjects. Inveestigators should examine the efficacy of varying levels of exercise intensity mode of muscle contraction, and duration of exercise program in comparing experimental groups against a control group. We also suggest that in addition to measuring peak torque, other dependent variables (eg, work, power, muscular endurance, functional task performance) may be valuable in assessng treatment efficacy for post-polio syndrome exercise regimens.

Very little research is available to guide the clinician in treating patients with post-polio syndrome who complain of diminishing muscle strength. The results of this case study suggest that an intensive exercise program may not have deleterious effects on the muscular performance of patients with post-polio syndrome. We suggest that clinicians should document and report the results of the exercise programs implemented with these patients to add to the knowledge base in this area. Controlled studies are needed to investigate the efficacy of post-polio syndrome exercise programs.

Acknowledgment

We thank Ruth Eden for her assistance in the production of the figures.

(1) 1 mile = 1.6093 km.

(2) Cybex, Div. of Lunex, Inc, 2100 Smithtown Ave, Ronkonkoma, NY 11779.

(3) 1 ft.lb = 1.356 Nm.

References

[1] Raymond M, Charcot JM: Paralysie essentiele de l'enfance: Atrophie musculaire consecutive. Gazette Medicale de Paris 4:225, 1875 (French)

[2] Cosgrove JL, Alexander MA, Kitts EL, et al: Late effects of poliomyelitis. Arch Phys Med REhabil 68:4-7, 1987

[3] Dalakas MC, Elder G, Hallett M, et al: A long-term follow-up study of patients with post-poliomyelitis neuromuscular symptoms. N Engl J Med 314:959-963, 1986

[4] Campbell AMG, Williams FR, Pearce J: Late motor neuron degeneration following poliomyelitis. Neurology 19:1101-1106, 1969

[5] Pietsch MC, Morris PJ: An assocation of HLA-A3 and HL-A7 with paralytic poliomyelitis. Tissue Antigen 4:50-55, 1974

[6] Johnson RT: Viral Infections of the Nervous System. New York, NY, Raven Press, 1982

[7] Alter M, Kurland LT, Molgaard CA: Late progressive muscular atrophy and antecedent poliomylitis. In Rowland LP (ed): Human Moto Neuron diseases. New York, NY, Raven Press, 1982, pp 303-309

[8] Dalakas MC, Sever JL, Madden DL, et al: Late post-poliomyelitis muscular atrophy: Clinical, virological, and immunological studies. Rev Infect Dis 6:5562-5567, 1984

[9] Mulder DW, Rosenbaum RA, Layton DO Jr: Late progression of poliomyelitis or forme frustration amyotrophic lateral sclerosis. Mayo Clin Proc 47 745-761, 1972

[10] Herbison GJ, Jaweed MM, Ditunno JF: Exercise therapies in peripheral neuropathis. Arch Phys Med Rehabil 64:201-205, 1983

[11] Muller EA: Influence of training and of inactivity on muscle strength. Arch Phys Med Rehabil 51:449-462, 1970

[12] Twist DJ, Ma DM: Physical therapy managemement of the patient with post-polio syndrome: A case report. Phys Ther 66:1403- 1406, 1986

[13] Alsentzer J: Post-polio syndrome. NC MED J 47:399-400, 1986

[14] Fillyaw M, Bevins T, Fernandez L: Importance of correcting isokinetic peak torque for the effect of gravity when calculating knee flexor to extensor muscle ratios. Phys Ther 66: 23-31, 1986

[15] Lesmes GR, Costill DL, Coyle EF, et al: Muscle strength and power changes during maximal isokenetic training. Med Sci Sports 10: 266-269, 1978

[16] Krotkiewski M, Aniansson A, Grimby G, et al The effect of unilateral isokinetic strength training on local adipose and muscle tissue morphology, thickness and ezymes. Eur J Appl Physiol 42:271-281, 1979

M Gross, PhD, PT, is Assistant Professor, Division of Physical Tehrapy, The University of North Carolina at Chapel Hill, CB# 7135. Medical School Wing E 222H, Chapel Hill, NC 27599-7135 (USA).

C Schuch, MS, PT, is Associate Professor, Division of Physical Tehrapy, The University of North Carolina at Chapel Hill.

THis article was submitted February 9, 1988; was with the authors for revision for five weeks; and was accepted June 6, 1988.