PRIMITIVE REFLEX PROFILE: A QUANTITATION OF PRIMITIVE REFLEXES IN INFANCY

Arnold J. Cupute Frederick B. Palmer Bruce K. Shupiro Renee C. Wuchtel Alan Ross Pusquule J. Accurdo

Primitive reflexes are brainstem-mediated responses that undergo significant evol- ution during the first year of life. They are present by birth and their suppression seems to be related to the development of normal motor function (Milani-Comparetti and Gidoni 1967u, b, Capute et ul 1982~) . They persist o r re-appear in the presence of brain damage and it is thought that they inhibit certain motor abilities among cerebral-palsied children (Molnar and Gordon 1976). Since existing information on the evolution of primitive reflexes is qualitative o r restricted to a presentlabsent dichotomy (Bleck 1975), a clinical grading on an ordinal scale was developed, similar to that used for the grading of deep-tendon reflexes. Such a scale is the necessary first step to a more refined description of motor development in infancy as the strength of reflex activity may be as predictive of motor disability, as its presence or absence.

While primitive reflexes have long been noted to be present in infants, attempts to quantify them have only been reported recently. Hoskins and Squires (1973) graded eight reflex behaviors in the first year of life but the scale reduced to a present/absent, normaVabnorma1 desig- nation which could not be used quantitat- ively. Mayberry (1974) studied newborns and developed a five-point scale which

focused on the stimuli required to elicit a response, rather than the character o r degree of the response. Touwen (1976), using data derived from monthly exami- nations of 5 1 normal infants, presented the developmental course of 70 items (in- cluding some primitive reflexes) used commonly in neurological and develop- mental assessments. While the sample size and selection prevented establishment of norms and the lack of abnormals prevented validation, Touwen did present a method of infant neurological assessment which was quantifiable.

The primitive reflex profile (PRP) study involves the prospective sequential evalu- ation of primitive reflexes and other aspects of motor development among infants from birth to two years of age. The examination was designed to score nine primitive reflexes: the asymmetrical tonic neck reflex (ATNR), the symmetrical tonic neck reflex (STNR), the positive support reflex (PS), the tonic labyrinthine reflex in supine (TLS) and in prone (TLP), the segmental rolling pattern, both head-on- body (SRHB) and body-on-body (SRBB), the Galant reflex (G) and the Moro reflex (M). The reflexes were selected and the grading system evolved from clinical observations of pathologically persisting primitive reflexes in cerebral-palsied

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TABLE I Primitive reflexes

children (Capute et al. 19786, Capute 1979). A brief description of each reflex is given in Table I. In general, the five-point scoring system was adjusted to classify each reflex as absent (0), minimally present, as by tone changes ( l ) , physiologi- cally present and readily visible (2), more strongly present (3) and obligatory or controlling the patient (4). A sample of the scoring system is give in Table 11; a detailed grading system has been published earlier (Capute er al. 1978a) and is summarized for each reflex in Figure legends 1 to 9.

Subjects and method The criteria for entrance into the study included birth at one of four participating hospital nurseries, planned pediatric follow-up at one of the co-operating pediatric groups or clinics and informed consent obtained in the newborn period. Although some infants had perinatal risk factors, normality was defined solely by the outcome measures described below.

A total of 381 infants were examined in the newborn nursery and then at each well- baby visit through to 24 months of age. The sex/race distribution is given in Table 111; the social-class (Hollingshead and Redlich 1958) distribution of the childrens' families is presented in Table IV. Gestational age by Dubowitz assessment was between 38 and 42 weeks inclusive. (Premature and postmature infants have been excluded from the present report.)

The assessment included a structured interval developmental history from the child's parent(s), a classic neurological examination for tone, deep tendon reflexes and Babinski reflexes, and an evaluation of graded primitive reflexes and several postural reactions. Each primitive reflex was scored on a five-point scale and it was noted whether the infant was crying or resisting the examination for that particular reflex. Consistency on three out of five trials was required for a particular score. These examinations usually were carried out just after the actual pediatric check-up.

A team of six developmental pedia- tricians trained in the research scales performed the evaluations over a period of 4% years. They had no record of the child's previous scores on the PRP or neurological evaluation. Inter-rater reliability studies were completed at regular intervals

% Interrater Reflex Description agreement

ATNR Supine: Rotation of head to one side produces extension of extremities on that side and contralateral flexion; the 'fencer' posture. Sitting: Head extension produces arm extension and leg flexion; head flexion produces arm flexion and leg extension. Vertical suspension: Stimulation of ball of foot produces leg extension to support weight. Supine: Extension of head produces shoulder retraction, leg extension. Prone: Head flexion produces shoulder protraction and leg flexion. Supine: Head flexion and rotation produces segmental (derotational) untwisting of body. Supine: Hip rotation produces segmental (derotational) untwisting of body. Prone suspension: Paravertebral stroking produces lateral flexion of trunk with concavity towards stimulated side. Supine: Sudden head extension produces abduction followed by adduction and flexion of upper extremities.

78 .2 r: 2 P STNR

95.0 PS

u 90.6

82 .5 TLS

TLP

75.0 SRHB

Y 81.7

81 .9

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72.1

TABLE I1 Sample primitive reflex grading for ATNR

0 Absent 1+ With passive head rotation, no visible

response, but increased extensor tone noted in extremities on chin side or increased flexor tone' on occiput side. (Active movement may elicit visible response.) With passive head rotation, visible extension of extremities on chin side or flexion on occiput side. (In some babies the visible component will be limited toflexion/extension of the fingers.) With passive head rotation, full (180") but transient extension in the extremities on the chin side or full (>90°) flexion of extremities on the occiput side. (The upper extremities of some babies with a positive tonic labyrinthine reflex will start from a position of flexion and, therefore, only slight visible movement will cause them to be scored 3+.) With passive head rotation, obligatory (more than 30secs) extension of extremities on chin side or flexion of extremities on occiput side.

2+

3+

4+

3 76 (From Capute et al. (1978)).

TABLE I11 Race and sex breakdown of PRP normative population

White

Male Female

White

Non-white (0 ’ 39) (0.35) (74%)

(0.13) (0.13) (26%) 198 183 38 1

(48%) (100%) (52%)

74 117 75 13 1 280 (0.19) (0.31) (0.20) (0.03) (0.00) (0.73)

TABLE IV Socio-economic status of normative population

Non-white 5 6 21 24 39 I (0.01) 1 (0.02) I (C S B j 1 (0.06) I (0.10) 79 123 96 37 40

(0.21) (0.32) (0.25) (0.10) (0.10)

Race 95

(0.25) 315*

(0.98)

I 2 3 4 5

I I I I I I

*Socio-economic status unknown for six infants. In Hollingshead’s two-factor index of social position, the lower numbers represent the higher socio-economic strata.

throughout the study and variation among examiners was within acceptable limits (Table I).

All 381 infants were designated as clinically normal, i.e. they had no signs of developmental disabilities at one year of age. This was confirmed by use of the Bayley Scales of Infant Development, performed on 374 of the children at about one year of age (1 1 to 18 months), and on the remaining seven by 26 months of age. Two children with mental and/or motor scores more than two standard deviations below the mean (68) were retested at 24 months of age, found to be within the normal range at that time, and therefore included in the normal group. The 381 infantshad a mean mental index of 103.7 (SD 13.4) and a mean motor index of 104.0 (SD 12.1). The motor milestones shown in Table V were obtained by history at each well-baby visit.

Results The PRP results for each reflex are presented in Figures 1 to 9. The bar charts give the distribution of reflex scores at each

age interval. For many infants there was considerable variation in the ages at which each well-baby check-up was accomplished and for this reason the interval limits in Table VI were employed. Thus, for example, children who received their two- month examination between 73 and 109 days of age would not have these data included in the bar charts. This explains the variable subject numbers. Third-degree polynomials were fitted for all valid data points (20,720) by the method of least squares to better illustrate the develop- mental trend for each reflex.

Composite bar chartdcurves are given for all the infants. When looked at separately by race and sex, there were occasional minor but non-significant differences. These were not considered clinically important given the nature of the scoring system and the distribution of scores at each age level.

The effect of crying/resistance was noted to increase the percentage of ‘missing’ scores (‘impossible t o complete examination or obtain reliable grading of reflex’) but did not otherwise influence the

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TABLE V Mean age (mths) of gross motor milestone attainment for normative population

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Milestone Mean S D No.

Rolls P S 3 . 6 1 . 4 Rolls S P 4 . 8 1 .4 Sits (supp.) 5 . 3 1 .0 Sits (unsupp.) 6 . 3 1 . 2 Comes to sit 7 . 5 1 .5 Creeps 6 . 7 1 . 5 Crawls 7 . 8 1 . 7 Pulls to stand 8 . 1 1 . 6 Cruises 8 . 8 1 . 7 Walks 11 .7 1 . 9 Walks backward 14 .3 2 . 4 Runs 14 .8 2 . 7

369 358 274 362 344 299 366 375 37 1 368 298 344

TABLE VI Age intervals established for PRP standardization

Age bracket Age (days) No examinationr

Newborn 0-6 346 2 weeks 13-19 247 2 months 53-73 297 4 months 109-136 294 6 months 172- 199 290 9 months 256-290 257

12 months 340-388 266 I5 months 431-479 25 1

18 months 522-570 225 24 months 697-759 203

distribution of scores. Thus, some reflex scores at certain ages were more difficult to obtain but when obtained, even with ‘cryinglresistance’, they exhibited a similar distribution to the scores of co-operative infants.

The ATNR (Fig. 1) is present in the majority of children at birth but does not reach its peak until about two months of age; it then steadily declines through the first year of life. The TLS (Fig. 2) has a similar evolution.

The TLP (Fig. 3) has a less pronounced evolution with a peak at four tosix months of age; the overlap of this reflex pattern with the traditional Landau response has been discussed elsewhere (Capute et a/. 1982b). The STNR (Fig. 4) is not found in most normal children using the current examination technique; it is observed

transiently with a peak between four and six months of age.

Both segmental rolling responses, SRHB and SRBB (Figs. 5 and 6), have evolved from a predominantly obligatory response (neck righting o r ‘log rolling’ in which the body turns as a single piece, hips and shoulders going over together) (scored 4), to a segmental pattern (2 or 3) and finally to a derotational score of 2. The grading system for both responses actually combines the decay or disappearance of the obligatory response (the true primitive reflex) with the appearance of the mature response of segmental rolling. Since averaging the scores of the development of the segmental rolling responses would make little sense, the two fitted curves for these reflexes represent the decay of the obligatory (‘4’) response.

The P s (Fig. 7) shows a constant increase over the first six months of life, reaching a plateau between nine and 12 months of age. The M reflex (Fig. 8) displays its expected rapid decay in the first six months of life; the G reflex (Fig. 9) shows only slight fading over the first year of life.

Discussion The nine primitive reflexes studied were selected because they were readily observ- able, underwent rapid change in the first year of life and were considered to be related to the onset of motor function in normal and brain-damaged children (Milani-Comparetti and Gidoni 1967a, b; Capute ef a/. 1982~) .

Both the ATNR and the TLS exhibit a similar pattern of evolution: present at birth in most infants, maximal strength two to four months, visible responses fading by the end of the first year of life, tone changes persisting into the second year of life, an obligatory response virtually never present normally and disappearance by two years of age. Clinically, these two primitive reflexes have been considered the most sensitive indicators of early motor abnormaiity. Two other reflexes that go to zero in their early development include the M, always present a t birth and gone by six months, and the STNR which is seen only briefly in a small percentage of normal children.

The TLP and G reflexes display more prolonged decay curves. With the TLP this

4. 100

80

60

40

20

0

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60 2 5 -

60 TLP s c o r e .

10- 40

20 5-

0

NEW 2 ,2 4 6 9 12 15 I6 24 BORN WKS "---------/

MONTHS ATNR

I 5 10 15 20 25 30 35 40 45 50 h

A g e in w e e k s

Fig. 1. Distribution of asymmetric tonic reflex ( A TNR) scores .for intervai examinations: bar chart and.firted curve (see text). Abbreviated scoring system as follows: 0 =absent: I + = appropriate tone change without position change; 2 + = visible, but not pronounced, position change; 3 + =pronounced change, <30 seconds; 4 + =obligatory position change. 2 3 0

0

I

2

u 3 seconds.

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MONTHS A g e in w e e k s T LS

Fig. 2. Distribution of ionic labyrinthine .supine (TLS) scores: 0 = absent: 1 + =appropriate tone change, no position change; 2 + = extension disappears with neck flexion, <5 seconds; 3 + =extension disappears with neck ,flerion, 5-30 seconds; 4 + =obligatory. extension remains for 30 secondr after neck Jlexion.

T L P

Fig. 3. Distribution of tonic labyrinthine prone (TLP) scores: 0 = absent; I + =appropriate tone change. no poyition change: 2 + =upper and lower e.xtremity.flexion. <90"; 3 + =upper and lower extremity flexion. >90". 4 + = obligatory, .sustained upper and [ower e.utremitv ,flexion >90"for >30 seconds.

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5

90- 60

70-

4 0 SRBB score

20 30 -

I O - 0

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% 345 244 293 291 265 256 261 242 217 166

8 0 30-

60 25-

STNR 20- 40 score lJ .

10-

05- 20

0 NEW 2 \2 4 6 9 I2 15 16 24, 10 20 30 40 50 60 BORN WKS

Age in w e e k s MONTHS STNR

Fig. 4. Distribution of symmetric tonic neck reflex (STNR) scores; O=absent; I + =appropriate tone change without position change: 2 f =visible, but not pronounced, position change; 3 f =pronounced position change, <30 seconds: 4 f =obligatory position change, 230 seconds.

344 247 295 268 267 219 206 151 123 139

80

60

40

20

0 NEW 2 \2 5 10 15 20 25 30 35 40 45 50 66 BORN WKS 4 6 9 I 2 15- I6 24

MONTHS A g e in weeks S R H 8

Fig. 5. Distribution of segmental rolling, head-on-body (SRHB) scores. O=no rolling when head rotated > 120" from supine; 1 + =derotational rolling when head rotated 90-120" f rom supine; 2 -k = derotational rolling when head rotated <90" from supine; 3 + = non-derotational rolling (1.e. lower extremities rotate before upper), 4 f =log rolling (i.e. upper and lower extremities rotate simultaneously).

Fig. 6. Distribution of segmental rolling, body-on-body (SRBB) scores: O=no rolling when hips rotated >120° from supine: I f = derotational rolling when hips rotated 90-120" f rom supine: 2 f = derotational rolling when hips rotated <90" from supine; 3 f = non-derotational rolling (i.e. upper extremities rotate before lower): 4 -+ =log rolling (i.e. lower and upper extremities rotate simultaneously). 380

346 245 297 294 290 252 257 243 218 196

80 2l 1 5

60

10 20 30 4 0 50 60 sro7ei:lf Age in weeks

40

20

0 NEW 2 \2 4 6 9 12 15 18 24/ BORN WKS

MONTHS PS

Fig. 7, Distribution of positive support (PS) scores: O=no weight bearing; I + =bears weight <30 seconds; 2 t =bears werght >30 seconds, heel on surface within 5 seconds, 3 f =bears weight 230 seconds, heels on surface between 5-30 seconds; 4+ =bears weight >30 seconds, on toes 30 second2 or more.

I O - 20

%

Age in weeks MONTHS MORO

Fig. 8. Distribution of Moro (M) scores: 0 =absent; I f =arm abduction and extension, no adduction; 2 + =arm abduction and extension followed by arm adduction; 3 t = 2 + with some trunk and lower extremity extension; 4 + = opisthotonus.

GALANT

Fig, 9. Distribution of Galani (G) scores: 0 =absent; I + = trunk incurvature more felt than seen; 2 + = trunk incurvature < 4 Y ; 3 + =trunk incurvature >4S0; 4 + = 3 + with hip elevation.

M

M Ic)

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is probably secondary to the STNR and Landau responses, interfering with the interpretation of the TLP. The G fails to show clear maturational changes and is consistent with the findings of Touwen (1976) who postulated interference from a 'tickle' response.

Unlike those reflexes which go to zero, the PS and both SR responses go to '2' . With the PS, two patterns are being measured: the decay of the primitive neonatal positive-support reflex (by six months) and the maturation of the true PS postural reaction (after four months). A transient exaggeration of the PS before one year of age is not abnormal. Supporting weight on the balls of the feet for between five and 30 seconds may be analogous to 'toe walking'. The PS findings are more consistent with Paine et al. (1964) than with Touwen (1976), who found that few children under six months of age supported weight for more than five seconds. Again, with both SR responses two patterns are being monitored: the decay of the true primitive reflex (log rolling) which is gone by six months and the maturation of the SR postural responses. Thus, although some of the difficulty in interpreting the results stems from the arbitrary nature of the grading system, the results reflect the complex interweaving of different response patterns which provide the reflex substrate for motor development.

This report documents the feasibility of applying a reflex grading system in an office setting and yields normative data that can be used in future studies of infant motor development. By using a uniform grading system such as the PRP, pro- fessionals will be better able to chart progress and communicate findings. Because the normal timetable for the appearance/disappearance of primitive reflexes is delayed significantly in cerebral- palsied children, changes in the evolution of such reflex patterns may be one of the earliest indicators of motor dysfunction (Paine et af. 1964, Stern 1971).

Obligatory responses in the ATNR, STNR, TLS o r T L P should always be a cause of concern. As has long been known about the Moro reflex, complete absence of the ATNR, TLS, TLP , SRHB, SRBB or G at birth suggests neurological abnormality. The significance of other deviations from the patterns described will need to be elucidated further, but clinical appli- cations should include the early diagnosis of cerebral palsy.

It is difficult t o diagnose cerebral palsy in the first six months because of poor predictability of isolated neurological signs such as stretch reflexes o r Babinski signs. By monitoring primitive reflex maturation and noting deviations from normal, additional information may be provided to allow early diagnosis of cerebral palsy. Paine et al. (1964) have shown this for single, obligatory reflexes. By using a compilation of multiple graded reflexes (Capute 1979) earlier diagnosis may be possible in the absence of obligatory findings.

AcknowledKements This study was supported by Maternal and Child Health Services Research Grant MC-R 240392, US Department of Health and Human Services. The co- operation of Harvey P. Katz, M.D. and the entire pediatric staff of the Columbia Medical Plan, Leroy Bernstein, M.D., the Baltimore City Hospitals, Sinai Primary Care Center a n d Park Heights Center, and The Johns Hopkins Hospital CCCC Clinic, in allowing the researchers access to their patient populations and use of their office facilities is greatly appreciared. Steven Schmidt, Liz Loden, Joanne Riley, Maureen Maguire and Rebecca Timmons have been instrumental in the completion of the study. Appreciation t o Amy Cronin for typing the manuscript. Figures were prepared under the supervision of Mr. Leon Schlossberg.

Aurhors' Appointments *Arnold J. Capute, M.D.; Frederick B. Palmer, M.D.; Bruce K . Shapiro, M.D. ; Renee C. Wachtel, M.D.; Alan Ross, Ph.D.; Pasquale J . Accardo, M.D.; The Department of Pediatrics, The Johns Hopkins University School of Medicine and The John F. Kennedy Institute for Handicapped Children, Baltimore, M D .

*Correspondence to first aurhor at 707 N. Broadway, Baltimore. MD 21205.

SUMMARY This report describes quantitative standardization data on nine primitive reflexes for a cohort of 381 normal infants evaluated longitudinally a t each visit between birth and two years of age. Normality was confirmed by the use of the Bayley Scales of Infant Development a t one year of age. The standardization of this new examination technique complements the traditional infant neurological examination and may allow primitive reflexes t o become a useful adjunct to the prediction of motor disability in early infancy.

RE SUM^ Profil ~ P Y rPfIere3 primairec: quant!fication des ref7eser primaires de la premiPre enfance Cet article rapporte les donnies de standardisation quantitative de neuf rkflexes primaires 6tablis ri partir d’une cohorte de 381 nourrissons normaux ktudies longitudinalement a chaque visite entre la naissance et I’ige de deux ans. La normalit6 a et6 confirm& cliniquement par I’utilisation des Bayley Scales of Infant Development a I’bge de un an. La standardisation de cette nouvelle technique d’examen complete I’examen neurologique traditionnel d u nourrisson et peut permettre a I’appreciation des reflexes primaires de devenir un appoint utile dans la prkdiction dcs troubles moteurs de la premiere enfance.

ZlJSAM M EN FASSUNG Profil der Primitivref7exe: eine Quantlfi’zierung der Primitivrefleue im Kindesalter Diese Arbeit beschreiht quantitative Standardisierungsdaten von neun Primitivreflexen bei einer Gruppe von 381 gesunden Kleinkindern, die von der Geburt bis zum Alter von zwei Jahren bei jeder Vorstellung genau unrersucht worden sind. Im Alter von ejnem J a h r wurden die Kinder anhand der Bayley Scales of Infanr Development untersucht und daran die Normalitat gemessen. Die Standardisierung dieser neuen Untersuchungstechnik ergantz die traditionellen neurologischen Untersuchungen des Kindes und kann eine sinnvolle zusatzliche Untersuchung zur Vorhersage motorischer Storungen im fruhen Kindesalter sein.

RESlJMEN Perfil de lot reflelos primitivos: cuant!ficacicin de 10s reflejos primitivos en nitios Este trabajo describe la estandardizacion cuantitativa de 10s datos d e nueve reflejos primitivos en un grupo de 381 lactantes normales evaluados longitudinalmente en cada visita entre el nacimiento y 10s d o s afios de edad. La normalidad se confirm6 con la Escala de Bayley del Desarrollo del lactante a1 afio de edad. La estandarizacion de esta nueva tkcnica de examen complementa el examnen neurologico tradicional y puede hacer que 10s reflejos primitivos constituyan un anexo util para la prediccion d e una incapacidad motora en la fase precoz de la lactancia

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Capute, A. J . (1979) ‘Identifying cerebral palsy in infancy through study of primitive reflex profiles.’ Pediatric Annals, 8, 589-595.

Accardo, P. J . , Vining, E. P. G., Rubenstein, J . E., Harryman, S. (1978a) Primitive Reflex Profile. MonoRraphs in Developmental Pediatrics, Volume I. Baltimore: University Park Press.

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Mayberry, W. (1974) ‘Developing infant predictors for sensory-integrative dysfunction.’ American Journal of Occupational Therapy, 28, 141 -143.

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- - (19676) ‘Routine developmental examin- ation in normal a n d retarded children.’ Develop- mental Medicine and Child Neurology, 9, 63 1-638.

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Paine, R. S., Brazelton, T . B., Donovan, D. E., Drorobaugh, J . E., Hubbell, J. P., J r . , Sears, E. M. (1964) ‘Evolution of postural reflexes in normal infants and in the presence of chronic brain syndromes.’ Neurology. 14, 1036-1048.

Stern, F. M. (1971) ‘The reflex development o f the infant .’ American Journal of Occupational Therapy. . . 25, 155-158.

Touwen, B. (1976) Neurological Development in lnfancv. Clinics in Develoumental Medicine. NG. 38. London: S.I.M.P.’ with Heinemann Medical; Philadelphia: Lippincott.

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