Effects of Hyperbaric Oxygen Therapy on children with Spastic Diplegic Cerebral Palsy     

     A Pilot Project

Montgomery, D., Ph.D., Goldberg, J., M. Sc., P.T., Amar, M., M.D.., Lacroix, V., M.D.

Lecomte, J., M.A., Lambert, J., Ph.D., Vanasse, M.,M.D.,  Marois, P., M.D.

 Affiliations:                     

1 McGill University

Hôpital Sainte-Justine

Hôpital Marie Enfant

Institut Maritime de Rimouski

Université de Montréal

Correspondence:

Dr. David Montgomery, McGill University

475 Pine Ave. West Montreal, QC, H2W 1S4

Tel: 514-398-4184 ext. 0558,   Fax: 514-398-4186

E-mail davidlm@glen-net.ca                   

August 21, 1999

  Abstract

HBO therapy for children with cerebral palsy (CP) is not new. Research documenting the effects in this population has been anecdotal. We evaluated the effects of HBO therapy for 25 children (X = 5.6 ± 1.6 years) with a functional diagnosis of spastic diplegic CP. Pre and post HBO evaluations consisted of the following measures: gross motor function (GMFM); fine motor function (Jebsen test for hand function); spasticity (modified Ashworth scale); video analysis; and parental questionnaire. The protocol for HBO therapy was 20 treatments of 95% oxygen at 1.75 atm abs for 60 minutes. The Wilcoxon matched pairs signed rank test for non-parametric measures was used to compare pre and post treatment data. Results showed improved gross motor function in 3 of the 5 items in the GMFM test, improved fine motor function in 3 of the 6 hand tests. reduced spasticitv in 3 of 4 muscle groups when assessed by a physician specializing in CP, and improvements for 4 of 9 questions posed to parents. HBO therapy appears to be a promising treatment for children with CP.

Key Words: Hyperbaric Oxygenation, Cerebral Palsy, Pediatrics

  Introduction

Cerebral palsy (CP) is a collection of diverse syndromes characterized by disorders of movement and posture caused by a non-progressive injury to the immature brain (1). The brain injury leading to CP can occur in the prenatal,  perinatal, or postnatal period (2). Almost half of all children with CP were born prematurely. The combination of immaturity, fragile brain vasculature, and the physical stresses of prematurity combine to predispose these children to compromised cerebral blood flow (3). In these children the cause of the brain injury is often elusive. The average prevalence rate for industrialized countries has been estimated at 2 per 1000 live births (4).

Cerebral palsy is classified two ways: by the type of muscle tone abnormality and the areas of the body that are affected (5). Increased muscle tone or spasticity is defined as a motor disorder characterized by a velocity dependent increase in tonic stretch reflexes (muscle tone) with exaggerated tendon jerks resulting from hyperexcitability of the stretch reflex, as one component of the upper motor neuron syndrome (6,7). Spasticity affects approximately 75% of all patients with CP (8,9). When characterized by body part, diplegia is the most common type. In spastic diplegia, there is an interruption of the pyramidal fibers originating from the cortical motor region that leads to spasticity. Hyperactivity of the alpha motor neurons results in spasticity, increased muscle tone, and hyperreflexia. Abnormalities of muscle tone are frequently accompanied by muscle weakness.

In order to improve motor function, treatments are often directed at reducing the spasticity in persons with CP. Pharmacology, surgery and physical therapy have been the standard approach for treatment of children with CP. Medications for spasticity are limited and sometimes have undesired side effects. Surgery, particularly selective dorsal rhizotomy, is the most effective treatment in reducing spasticity but not all children with CP are appropriate candidates for this procedure (10, 1). Few studies have documented long term improvements from physical therapy (12.13,14).

Hyperbaric oxygen therapy (HBO) has been used to treat children with CP for a number of years. Recently, there has been a return to this treatment in China. England. Germany. Russia. South Africa, and the United States. There is at the present time, no scientific evidence to support the use of HBO to treat these children. One anecdotal report (15) summarized the clinical-experience in Brazil showing a reduction in spasticity following HBO treatments for patients with neurological impairments. Due to the desire of parents to seek out this treatment for their children at significant financial expense, we felt it was our responsibility to objectively evaluate the efficacy of HBO treatment for persons with CP prior to recommending this option to parents. The objectives in this pilot study were to examine if HBO treatments would alter: (1) gross motor function, (2) fine motor control, and (3) muscle spasticity in children with CP.

  Methods

Subjects: Twenty-five volunteer subjects with a mean age 5.6 ± 1.6 years (range 3.1 - 8.2 years) participated in this study. Subjects consisted of 10 girls and 15 boys with a functional diagnosis of spastic diplegia. Potential subjects were obtained by referrals from rehabilitation centers in Quebec and/or requests from parents. In order to be considered for participation in the study, subjects had to meet the following inclusion criteria: 1) functional diagnosis of spastic diplegia; 2) age range from 3 to 8 years; 3) functional plateau in rehabilitation for the last 12 months (defined as no measurable functional changes in gross motor performance as documented by their physical therapist); 4) ability to understand and respond to verbal instruction; and 5) medical clearance for HBO therapy. Children were excluded from: the study if any of the following criteria were present in their medical history: previous rhizotomy, recent thoracic surgery, epilepsy, cancer, chronic asthma, ventriculo-peritoneal shunts and previous HBOT therapy. In addition children taking anti-spasticity medication or those with behavior problems were also excluded.

Of the 60 children that met the inclusion/exclusion criteria, 25 were randomly selected. Informed consent was obtained from the parent or legal guardian of each child prior to participation in the study. The study was approved by ethical review committees at McGill University in Montreal and the Regional Hospital in Rimouski, Quebec. No children received physical or occupational therapy during the course of the study.

Procedures: The same therapists conducted pre and post treatment evaluations which were separated by 37.2 ± 8.0 days. The procedures for these evaluations were identical and are outlined below. The physical and occupational therapists worked in a hospital setting and were accustomed to administering the GMFM test Jebsen test and modified Ashworth scale. They had no contact with the children during the HBO treatments. Each evaluation consisted of the following five tests:

1. Gross Motor Function: The Gross Motor Function Measure (GMFM) was used since it is a standardized index of gross motor function for children with cerebral palsy (16,17). The GMFM is a criterion based observational measure (88-items) that assesses motor function in five dimensions. The five dimensions and their respective maximum scores are: A =lying and rolling (51), B = sitting (60), C = crawling and kneeling (42), D = standing (39), and E = walking, running and jumping (72). Each item is scored on a 4-point scale (0 = does not initiate activity, 1 = initiated activity, 2 = partially completes activity, 3 = completes activity). Specific descriptions on how to score each item are found in the administration and scoring guidelines in the test manual (18). The physical therapist who administered the test had been trained and had several years experience using the test. Subjects completed each item of the GMFM test and were given a score for each dimension by the physical therapist.

2. Fine Motor Function: Fine motor function was evaluated with the Jebsen Test, which is an objective and standardized 7-item assessment of hand function (19). An occupational therapist administered the following 6 items or sub-tests: 1) turning over 3 by 5 inch cards: 2) picking up small objects and placing them in a container: 3) stacking checkers; 4) simulated eating; 5) moving empty large cans; and 6) moving weighted large cans. The seventh item (writing a short sentence) was omitted due to the age of some of the children. Subjects remained seated during the test. The sub-tests were presented in the same sequence, administered in the same manner and were always performed with the non-dominant hand first. After the instructions were given, the child was asked if he/she understood the task to be performed before starting the sub-test. Each task was timed by the occupational therapist with a score in seconds recorded for each sub-test for the dominant and non-dominant hands.

3. Spasticity Level: Spasticity was evaluated using the modified Ashworth scale (MAS) (20) in four muscle groups (hip adductors, quadriceps femoris, hamstrings. and ankle plantar flexors). Spasticity was graded from 0 (no increase in muscle tone) to 4 (affected part rigid in flexion or extension) on a 6-point scale. During the pre and post evaluations, spasticity was evaluated separately by a physician and physical therapist with each assigning a score for the level of spasticity for each muscle.

4. Video Analysis: Subjects were recorded on videotape pre and post treatment performing numerous gross motor and fine motor tasks (e.g. pedaling their legs, rolling, sitting, crawling. standing, walking, reaching and coloring). Each videotaping session was recorded on a separate cassette with no date or time stamp. The videotapes were randomly analyzed by 2 pediatric physical therapists and were only viewed at the end of the study. The physical therapists were blinded and did not know if they were viewing a performance pre or post HBO therapy. Therapists viewed the pre and post tapes simultaneously on two monitors and rated one video as "better” if motor function was improved.

5.  Questionnaire: A 9-item questionnaire was administered verbally by the physical therapist to the same parent of each subject pre and post HBO therapy. The questionnaire included the following categories: 1) walking; 2) walking on knees; 3) crawling; 4) sitting on the floor: 5) sitting on a bench; 6) undressing; 7) eating; 8) bath and personal hygiene: and 9) communication. The scale of independence (5-point scale) for each category ranged from 0 to 4 (0 = dependent, no participation: 1 = dependent, participates but requires constant help throughout the activity; 2 = dependent, needs help only to finish the activity; 3 = independent with some form of aid or compensation: 4 = independent). Each category consisted of 3 - 4 questions in order to determine the child's level of autonomy and to assign the appropriate score.

HBO therapy: Subjects were randomly assigned to one of two hyperbaric oxygen treatment units. Ten children received HBO treatment at the Cleghorn Hyperbaric Oxygen Laboratory of McGill University and 15 children received HBO treatment at the Centre Hospitalier Regional de Rimouski. The protocol for the HBO therapy was 95% oxygen at 1.75 atm abs for 60 minutes. All subjects received 20 HBO treatments. The schedule of treatments at McGill University was: 1 treatment/day; 5 days/week for 4 weeks in a monoplace hyperbaric chamber (Sigma Plus Monoplace Hyperbaric System, Perry Baromedical, Riviera Beach, FL) that was pressurized with 95% oxygen. During treatments, a parent or guardian accompanied the child in the hyperbaric chamber. The schedule of treatments at the Centre Hospitalier Regional de Rimouski was: 2 treatments/day; 5 days/week for 2 weeks in a multi-place (6 person) hyperbaric chamber that was pressurized with air and oxygen delivery to the patient via a hood. Pressure equalization (P.E.) tubes were inserted in the ears of 13 children to facilitate compression discomfort in the multi-place unit.

Data Analysis: For data analysis, each child served as his/her own control by using pre HBO scores as the baseline for comparison. Since the children ranged in age from 3 to 8 years of age, measurements of the dependent variables resulted in large inter-individual variability. The mean and S.D. results for each dependent variable are summarized for pre and post evaluations. In addition, the data for the GMFM test were analyzed to determine the percent change between pre and post evaluations for each child. The Wilcoxon matched-pairs signed-ranks test was used to determine significant changes from the pre to post test for the GMFM test, functional evaluation of the hand, spasticity evaluation, and the 9-item questionnaire to the parents. Statistical significance was determined if p < 0.05.

  Results

Results of the GMFM are illustrated in Table 1 as a percentage of the maximum score for each dimension. Maximum scores were: A (51), B (60), C (42), D (39), and E (72). Significant (p <0.05) improvements from pre to post evaluation were observed for dimensions B (sitting), D (standing) and E (walking, running, jumping). Table 1displays the results of the GMFM test for each child. The average improvement in the total GMFM score was 5.3%.

Table 1. Individual Results for the GMFM Test.
	Item A		Item B		Item C		Item D		Item E		Total		Percent
Subject	Pre	Post	Pre	Post	Pre	Post	Pre	Post	Pre	Post	Pre	Post	Change
1	51	51	57	57	30	39	17	26	14	18	169	191	13.0%
2	35	36	16	12	1	0	0	4	1	3	53	55	3.8%
3	51	51	60	60	42	42	39	38	71	71	263	262	-0.4%
4	49	51	57	59	37	38	20	21	10	13	173	182	5.2%
5	10		10		0		0		0		20
6	51	51	58	59	40	40	32	32	50	50	231	232	0.4%
7	49	48	34	36	5	12	1	5	3	3	92	104	13.0%
8	41	45	35	33	25	21	8	4	2	2	111	105	-5.4%
9	51	51	59	59	34	35	22	26	14	15	180	186	3.3%
10	51	51	60	60	42	42	39	35	55	68	247	256	3.6%
11	49	49	46	53	39	32	20	11	11	12	165	157	-4.8%
12	48	48	32	42	32	34	11	12	8	7	131	143	9.2%
13	49	49	59	57	35	40	16	26	10	12	169	184	8.9%
14	49	49	58	56	37	34	10	18	12	10	166	167	0.6%
15	49	49	48	56	38	34	11	21	9	9	155	169	9.0%
16	51	49	37	53	31	28	7	21	9	9	135	160	18.5%
17	29	28	14	13	3	2	2	2	3	3	51	48	-5.9%
18	51	49	57	58	30	24	20	22	16	15	174	168	-3.4%
19	47	49	30	34	13	23	2	6	3	5	95	117	23.2%
20	48	49	50	50	29	23	5	5	3	5	135	132	-2.2%
21	49	49	60	60	41	39	32	31	51	56	233	235	0.9%
22	49	48	24	27	22	21	2	3	3	5	100	104	4.0%
23	49	51	55	58	34	39	27	26	30	35	195	209	7.2%
24	51	51	60	60	40	39	28	32	39	41	218	223	2.3%
25	47	49	21	29	21	27	5	8	2	5	96	118	22.9%
Mean	46.2	48	43.9	47.5	28	29.5	15	18.1	17	20	150	163	5.3%
Maximu	51		60		42		39		72		264

 

Table 2 summarizes the results for the functional evaluation of the hand. Scores were measured objectively since time to complete each test was recorded. There was a significant improvement in 3 of the 6 tests - turning cards, moving large cans, and moving weighted cans. Total time for the six tests averaged 260 seconds on the pre test and 221 seconds on the post test.

Table 2. Functional Evaluation of the Hand (X ± S.D.)
Task (seconds)	Pre HBO		Post HBO		p
	Dominant	Non-Dom	Dominant	Non-Dom	Dom	N-D
Turning cards	17.9 ± 12.7	20.4 ± 13.7	15.1 ± 10.3	17.3 ± 11.2	**	*
Picking up small objects	21.0 ± 10.7	24.2 ± 14.5	20.7 ± 16.1	22.1 ± 11.8
Moving large cans	15.8 ± 11.2	15.1 ± 8.9	11.7 ± 6.3	11.4 ± 5.9	**	*
Moving weighted cans	18.6 ± 17.9	15.1 ± 8.5	11.8 ± 7.4	11.6 ± 5.7	**	*
Simulating eating	50.0 ± 42.0	37.6 ± 22.6	35.6 ± 24.1	40.9 ± 33.9
Staking checkers	11.6 ± 7.7	12.8 ± 10.4	10.7 ± 8.0	11.9 ± 6.9
* p value < 0.05
** p value < 0.01

Spasticity was evaluated subjectively by a physician and a physical therapist using the 6-point MAS (0, 1, 1+, 2 3,4). Both individuals had extensive clinical experience assessing children with cerebral palsy. The assessment by the physician determined significant reduction in spasticity in the hip adductors, hamstrings, and ankle plantar flexors. In contrast, the physical therapist noted improvement in only one muscle group - left quadriceps femoris.

Table 3. Spasticity Evaluation - modified Ashworth scale (X ± S.D.).
The values represent scores that range from 0 (no increase in muscle
tone) to 4 (affected part rigid in flexion or extension).
Muscles	Evaluator	Limb	Pre HBO	Post HBO	p
Hip	PT	Right	1.16 ± 0.7	1.30 ± 0.8
		Left	1.06 ± 0.8	1.16 ± 0.8
Adductors	MD	Right	1.28 ± 0.8	0.78 ± 0.7	p < 0.01
		Left	1.32 ± 0.8	0.78 ± 0.7	p < 0.01
Quadriceps	PT	Right	0.78 ± 0.9	0.76 ± 1.0
		Left	0.88 ± 0.8	0.64 ± 0.7	p < 0.05
Femoris	MD	Right	1.40 ± 0.8	1.08 ± 1.0
		Left	1.36 ± 0.8	0.96 ± 1.0
Hamstrings	PT	Right	0.42 ± 0.6	0.30 ± 0.5
		Left	0.12 ± 0.4	0.16 ± 0.5
	MD	Right	1.34 ± 0.6	0.84 ± 0.7	p < 0.01
		Left	1.34 ± 0.6	0.92 ± 0.8	p < 0.01
Ankle	PT	Right	1.74 ± 0.6	1.62 ± 0.7
Plantar		Left	1.54 ± 0.6	1.60 ± 0.7
Flexors	MD	Right	1.87 ± 0.7	1.16 ± 0.9	p < 0.01
		Left	1.79 ± 0.8	1.14 ± 0.9	p < 0.01
PT - physical therapist
MD - physician

For the video analysis, two “blinded" reviewers with no knowledge as to whether the tapes were recorded pre or post HBO treatments performed the analysis. Their evaluation provided an objective assessment of gross motor function. The post test video was rated as displaying better movement for 16 children (67%), while the pre test video was rated as better for 7 children (29%). The videos were rated as equal for one child. One child was not filmed on the post-test.

The responses of the parents to the questionnaire items were rated on a 5-point scale by a physical therapist. These results are illustrated in Figure 2. For statistical analysis, the pre and post scores for each child were compared. An example of the assessment technique for question 1 (walking) is summarized in Table 4. The “shaded" area across the diagonal represents unchanged scores from pre to post test. Scores to the right of the diagonal represent improvement while scores to the left of the diagonal represent decreased performance. For question 1, nine children demonstrated increased scores, in fifteen children the scores were unchanged, and no children were rated as having decreased scores. Table 5 summarizes the results for the 9 questions to the parents. Significant (p <0.05) improvement occurred for 4 activities - walking, high kneeling walking, sitting on the floor, and sitting on the bench.

Table 4.	The Responses of the Parents (n=24) to Q1 (Walking) as interpreted by the
	Physical Therapist. The values represent scores that grade the amount of
	independence of the child and range from 0 (dependant, no participation by the
	child) to 4 (independent).
Pre HBO	Post HBO Treatments
Treatments	0	1	2	3	4
0
1		1	2
2			6	5
3				5	2
4					3

 

Table 5.	Questionnaire to the Parents. The numbers represent the number of children (n= 24)
	that had increased, were unchanged, or had decreased scores when the post
	evaluation was compared to the pre-evaluation for each question.
Question	Post HBO vs Pre HBO			p
	Increased	Unchanged	Decreased
Walking	9	15	0	0.01
High Kneel walking	8	16	0	0.01
Crawling	4	19	1	0.14
Sitting on the floor	12	12	0	0.01
Sitting on the bench	10	14	0	0.01
Undressing	4	20	0	0.07
Eating	2	22	0	0.18
Personal hygiene	2	22	0	0.18
Communication	1	23	0	0.32

In addition, parents noted changes in their children that were not measured in our assessment. They verbally reported improvements in alertness, concentration. quality of sleep, and ability to communicate both verbally and non-verbally. Question 9 (pertaining to communication) was specific to speech and did not examine non-verbal communication skills. Following the completion of the study, most children returned to the care of their therapists (both physical and occupational). These professionals reported changes that supported the impressions of the parents.

  Discussion

This is the first study to objectively evaluate the effects of HBO therapy for children with CP. Following 20 HBO treatments, our findings demonstrated improved gross motor function in 3 of the 5 items in the GMFM test, improved fine motor function in 3 of the 6 hand tests of the Jeben evaluation, and reduced spasticity in 3 of 4 muscle groups when assessed by a physician specializing in the management of children with cerebral palsy. In addition, significant improvements were noted for 4 of the 9 questions posed to the parents.

There are risks associated with HBO therapy including oxygen toxicity, pneumothorax, barotrauma (e.g. sinuses, middle ear), and visual changes as possible side effects as well as risk of fire. In our opinion, the benefits of HBO therapy for 60-minutes at 1.75 atm abs outweigh the potential risks.

Since the children with CP had reached a functional plateau in their rehabilitation, no measurable changes in gross and fine motor function were expected during the two-month duration of this study (21). Changes in the GMFM overall score are considered genuine improvements in motor function (18) since the GMFM consists of observations on 88 items. The overall changes in the GMFM scores seen in our subjects was an improvement of 5.3% which is well within the mean of the reported expected changes following intensive (twice a week) physical therapy. Two recent studies (18,22) document the expected functional changes in children with spastic diplegia following intensive physical therapy programs lasting 6 and 3 months respectively. They reported increases in GMFM scores of 3.7% and 7.0%, respectively. However, it is important to note that the children in our study received only HBO treatments which were administered over a one month period and received no physical therapy.

In the GMFM test dimension A (lying and rolling) and C (crawling and kneeling) did not change significantly from pre to post test. Lack of significance for dimension A may be attributed to the high functioning level of the children on the pre test which was 91% of the maximum score. Dimension C included crawling which was the primary mode of locomotion for these children and therefore is difficult to change over a short period of time.

The divergent findings for the spasticity evaluations conducted by two health care professionals both with extensive experience in pediatric rehabilitation however are more difficult to interpret. Clinically, it is known that spasticity is a difficult variable to quantify. The MAS is the most commonly used method to evaluate spasticity. Despite its wide spread use in clinical and research settings, it remains a subjective tool and as a consequence its reliability has been questioned particularly for lower extremity muscle groups (23, 24). More objective methods of quantification such as electromyography, deep tendon reflex tests, and resistance to motion tests are methodologically difficult to use in the evaluation of spasticity in young children (25). In our study, pre test MAS scores for all muscles averaged 0.96 for the physical therapist and 1.46 for the physician, a discrepancy of 0.5 units on the MAS. These values reflect low levels of muscle spasticity at the onset, and therefore make measurable decreases in spasticity difficult to assess. In addition, the testing positions for the evaluation of each muscle group were not standardized and evaluations conducted by the physician and therapist were not always on the same day. This may explain the conflicting results since it is known that spasticity levels are affected by a host of external events such as fatigue, excitability, fear and discomfort which can vary from day to day (6,26).

Future studies will attempt to improve inter-rater reliability of the MAS by establishing specific evaluation criteria, with rater training given prior to the study, and by conducting the evaluation of the children consecutively by each evaluator. We recognize that there are other limitations in this pilot study that include the absence of an independent control group, no placebo treatment, small sample size, number of treatments (20), different treatment protocols conducted in Montreal and Rimouski, as well as the subjective nature of some of the evaluations. However, the encouraging findings from this pilot study will result in a multi-centre trial in Quebec that will include a placebo group a greater number of treatments (40), more objective measurements, and multiple post HBO evaluations to determine if benefits are retained. In addition, the effects of HBO on speech, language, concentration and alertness will be examined in this future study.

  References

1. Molnar GE. Cerebral palsy. In Molnar GE (ed): Pediatric Rehabilitation, Baltimore. Williams & Wilkins. 1985,481-533.

2. Kudrjavcev T. Schoenberg BS_,  Kurland LT. Groover, RV. Cerebral Palsy: Trends in incidence and changes in concurrent neonatal mortality: Rochester. Mn, 1985 - 1970. Neurology 1983; 33:1433-1438.

3. Bozynski MEA, Nelson MN, Genaze D, Rosati-Skertich, C, Matalon. TAS. Vasan, U, Naughton, PM. Cranial ultrasonography and the prediction of cerebral palsy in infants weighing < 1200 grams at birth. Developmental Medicine and Child Neurology 1988; 30:342-348.

4. Biether JK, Cummins 5K, Nelson KB. The California cerebral palsy project Pediatric Perinatology and Epidemiology 1993; 6:339-351.

5. Stempien LM. Gaebler-Spira D. Rehabilitation of children and adults with cerebral palsy. In: Physical Medicine and Rehabilitation. Braddon. RL, Buschbacher. R, Dumitra, D, Johnson. EW. Matthews, D, Sinaki, M.eds., Saunders, 1996, pp. 1113-1132.

6. Katz RT, Rymer WZ. Spastic hypertonia: Mechanisms and measurement. Archives of Physical Medicine and Rehabilitation 1989; 70:144-155.

7. Lance JW. Symposium Synopsis. In: Feldman RG, Young RR, Koella WP Spasticitv:Disordered Motor Control. (Eds). Chicago: Yearbook Publishers: 1980. p. 485494.

8. Krageloh-Mann ~ Hagberg G, Meisner C, Schelp B, Haas G, Eeg-Olofsson KE, Hagberg B,

Michaelis R. Bilateral spastic cerebral palsy - A comparative study between southwest

Germany and western Sweden. I Clinical patterns and disabilities. Developmental

Medicine and Child Neurology 1993; 35:1031-1047.

9. Kudrjavcev T, Schoenberg BS, Kurland LT, Groover RV. Cerebral palsy: Survival rates, associated handicaps, and distribution by clinical subtype. Rochester, MN 1950 - 1976. Neurology 1985; 35:900-903.

10. Park TS, Owen JH. Surgical management of spastic diplegia in cerebral palsy. The New England Journal of Medicine 1999 326:745-749.

11. Peacock WJ, Staudt LA. Spasticity in cerebral palsy and the selective dorsal rhizotomy procedure. Journal of Child Neurology 1990; 5:179-185.

12. Herndon WA, Troup P, Yngve DA, et al. Effects of neurodevelopmental treatment on movement patterns of children with cerebral palsy. Journal of Pediatric Orthopedics 1987; 7:395-400.  

13. Mayo N. The effect of physical therapy for children with motor delay and cerebral palsy: A randomized clinical trial. American Journal of Physical Medicine and Rehabilitation 1991; 70-258-267.  

14. Palmer FB, Shapiro BK, Wachtel RC, Allen, MC, Hiller JE. Harryman SE. Mosher BS. - Meinert CL, Capute AJ. The effects of physical therapy on cerebral palsy. A controlled trial in infants with spastic diplegia. The New England Journal Medicine 1988: 318:803-808.  

15. Machado JJ. Reduction of spasticity, clinicallv observed in patients with neurological diseases, submitted .to hyperbaric oxygen-therapy specially children with cerebral palsis. Transcripts from the annual meeting of the Undersea and Hyperbaric Medicine conference, 1969.  

16. Russell DJ, Rosenbaum PL, Cadman DT, Gowland C, Hardy S. Jarvis S. The Gross Motor Function Measure: A means to evaluate the effects of physical therapy. Developmental Medicine and Child Neurology 1989; 31:341-352.  

17. Nordmark E. Hägglund G. Jarnlo GB. Reliability of the Gross Motor Function Measure in cerebral palsy. Scandinavian Journal of Rehabilitation Medicine 1997; 29- 95-~8  

18. Russell DJ, Rosenbaum PL, Gowland C, Hardy S. Lane M, Plews N. McGavin H. Cadman D, Jarvic S. A measure of Gross Motor Function in Cerebral Palsy. Gross Motor Function Measure Manual 1990, McMaster University; Hamilton: Ont.  

19. Jebsen RH. Taylor N, Trieschmann RB, Trotter MJ, Howard LA. An objective and standardized test of hand function. Archives of Physical Medicine and Rehabilitation 1969; 50:311-319.  

20. Bohannon RW, Smith MB. Interrater reliabilitv of a modified Ashworth scale of muscle spasticity. Physical Therapy 1987; 67(2): 206-207.  

21. Haley SM. Coster WJ, Ludlow LH. Pediatric functional outcome measure. Physical Medicine and Rehabilitation Clinics of North America. 1991 ;4(2): 689-723.  

22. Trahan J, Malouin F. Changes in gross motor function measure in children with different types of cerebral palsy: An eight-month follow-up study. Pediatric Physical Therapy 1999-11-19-17.  

23. Sloan RL, Sinclair E, Thompson J, Taylor S, Pentland B. Inter-rater reliability of the modified Ashworth scale for spasticity in hemiplegic patients. International Journal of Rehabilitation Research 1992; 15:158-161.  

24. Engsberg JR, Olree KS, Ross SA, Park TS. Quantitative clinical measure of spasticity in children with cerebral palsy. Archives of physical Medicine and Rehabilitation 1996: 77: 594-599.  

25. Kathrein JE. Inter-rater reliability in the assessment of muscle tone in infants and children. Physical and Occupational Therapy in Pediatrics 1990:10(1): 27-4 I  

  Acknowledgments

This project was funded by La Fondation Maurice Tanguay, L'Association de Ia Paralysie Cerebrale du Quebec, Hopital Marie Enfant and its Foundation. We also wish to thank the therapists who took part in the evaluation of the children (N. Leclerc P.T. and L Audette O.T.), and personnel from the Hopital Marie Enfant (S. Desrochers and C. Gagnon) who assisted with this study. We are grateful to the staff of the hyperbaric chamber in Rimouski and the Centre hospitalier regional de Rimouski.

  Legends

Figure 1. GMFM test results expressed as a percent of maximum potential score

Figure 2. Responses of the parents to a 9-item questionnaire