Elsevier

Early Human Development

Volume 90, Issue 8, August 2014, Pages 387-392
Early Human Development

Jerky spontaneous movements at term age in preterm infants who later developed cerebral palsy

https://doi.org/10.1016/j.earlhumdev.2014.05.004Get rights and content

Highlights

  • We have identified characteristics of spontaneous movements at term age in preterm infants who later developed CP.

  • Infants who developed CP by 3 years of age showed more often jerky movements than those who developed normally.

  • Computer-based video analysis system can be useful in quantifying the spontaneous movements at term age for predicting CP.

Abstract

Background

Assessment of spontaneous movements in infants has been a powerful predictor of cerebral palsy (CP). Recent advancements on computer-based video analysis can provide detailed information about the properties of spontaneous movements.

Aims

The aim of this study was to investigate the relationship between spontaneous movements of the 4 limbs at term age and the development of CP at 3 years of age by using a computer-based video analysis system.

Study design and subjects

We analyzed video recordings of spontaneous movements at 36–44 weeks postmenstrual age (PMA) for 145 preterm infants who were born preterm (22–36 weeks PMA with birthweights of 460–1498 g). Sixteen of the infants developed CP by 3 years of age, while 129 developed normally. We compared 6 movement indices calculated from 2-dimensional trajectories of all limbs between the 2 groups.

Results

We found that the indices of jerkiness were higher in the CP group than in the normal group (p < 0.1 for arms and p < 0.01 for legs). No decline was observed in the average velocity and number of movement units in the CP group compared with to the normal group.

Conclusions

Jerkiness of spontaneous movements at term age provides additional information for predicting CP in infants born preterm.

Introduction

Young infants exhibit spontaneous movements of the entire body including the arms, legs, and trunk. Spontaneous movements with complex and fluent properties of the entire body, which are referred to as “general movements,” emerge in early gestational age and change in their movement properties from “writhing” to “fidgety” within the second month of post term age [1], [2], [3]. General movements have been thought to reflect the status of the development of the central nervous system. Therefore, dysfunction of young nervous systems can be reflected by alterations in general movements [1], [2], [3]. Qualitative assessment of general movements has been used as a diagnostic tool for predicting neurodevelopmental disorder. For a systematic review of the predictive validity of qualitative assessment of general movements with respect to neurodevelopmental outcome see [4]. Cerebral palsy (CP) can be predicted by assessment of “fidgety movements,” which consist of a continuous stream of tiny elegant movements observed at 9–20 weeks—post-term [4], [5], [6], [7], [8], [9], [10], [11]. In particular, the absence of fidgety movements is a powerful predictor of CP [8], [10], [11]. Moreover, assessment of the motor repertoire or specific movement characteristics around 3 months post-term improves the predictive power for CP [5], [9], [12]. Studies on computer-based video analysis of spontaneous movements between 10 and 15 weeks post-term also showed that this quantitative method could predict CP in high-risk infants [13], [14].

Regarding the relationship between movements at term age (36–44 wks postmenstrual age [PMA]) and developmental outcome, qualitative assessment of the general movements, which are called “writhing movements,” is a good predictor of CP [1]. In particular, the presence of “cramped-synchronized” movement has high predictive value for spastic CP [7], [8], [15]. A single preterm general movement assessment is also moderately associated with functional motor outcome at 14 months [16]. Although the assessment of spontaneous movements at term age may have lower predicting value for CP than that at 3–4 months of ages [3], [8], computer-based movement analysis at term age will provide crucial information for understanding neurological development and predicting outcome. A recent study using computer-based video analysis has shown that specific characteristics of spontaneous movements in preterm infants at term age are associated with developmental delays at 3 years of age [17]. Although that study did not include children definitively diagnosed with CP, the same analysis can be applied to study the relationship between spontaneous movements at term age and later development of CP.

The present study compared the spontaneous movements at term age in children who had no abnormality at 3 years of age with those in children who were diagnosed with CP by 3 years of age by computer-based analysis of time series of limb movements. We hypothesized that the limb movements at term age in children who later developed CP may be more jerky than those in children who had no abnormality. This hypothesis is based on a theory of human motor control which showed that movements of limbs are controlled in such a way that jerk (rate of acceleration) of movements is minimized [18] and the generation of smooth movements may be mediated by the cortical mechanisms. Since precursory supraspinal mechanisms for movement generation have been considered to be present at term age in typically developing infants [19], disorder of supraspinal mechanisms, which can lead to later CP, may be reflected as production of jerky movements even at term age. In the present study, we examined not only jerk index but also other indices, as used in the previous study [17], to reveal the properties of spontaneous movements at term age in children who later developed CP.

Section snippets

Participants

This study was conducted as part of a prospective observation of infants born between 2002 and 2010 in the Neonatal Intensive Care Unit (NICU) at the Nagano Children's Hospital, Japan, which is specialized to perinatal care and admits high-risk infants born preterm with low-birthweight. We retrospectively selected the preterm infants who developed CP and who developed typically at 3 years of age. Fig. 1 shows the flow diagram of the study children. 884 infants were enrolled in this study. A

Participant characteristics

The characteristics of the infants in the CP (n = 16) and normal groups (n = 129) are shown in Table 1. No significant group differences were found in birthweight, gestational age, percentage of participants with Apgar scores at 5 min < 7, and the age at recording. Assessments by ultrasound and/or MRI revealed periventricular leukomalacia (PVL) (n = 6; 5 were in the CP group and 1 was in the normal group), intraventricular hemorrhage (IVH) (n = 12; 5 were in the CP group (grade I, II, and IV were 1, 1,

Discussion

In the present study, we found evidence that the jerkiness calculated by 2D trajectories of infants' movements at term age can be associated with CP development. The jerk index of the CP group was higher than that of the normal group. This is in line with previous studies that have regarded the jerkiness of spontaneous movements of preterm and term infants as an indicator of neurological abnormality [1], [25]. However, in a previous study on general movements at age 9 to 13 weeks post-term, the

Conclusion

A computer-based video analysis revealed that higher jerkiness of spontaneous movements at term age is associated with later development of CP in preterm-born infants. A possible explanation for this is that disorder of precursory supraspinal mechanisms for movement generation at term age may be reflected as production of jerky movements.

Conflict of interest

There were no conflicts of interest.

Acknowledgments

We would like to thank Hiroki Oohashi for his appropriate suggestions about statistical analysis and Ryoya Saji, Rieko Takaya, Yoshiharu Yamamoto, and Daichi Nozaki for their helpful discussions. We would like to thank Kayo Asakawa, Yoshiko Koda, and Keiko Hirano for their administrative assistance. We also thank the parents and infants who participated in this study. This work was partly supported by a Grant-in-Aid for Scientific Research (no. 20670001 and no. 24119002 to G.T.), Clinical

References (35)

  • H.F.R. Prechtl

    General movement assessment as a method of developmental neurology: new paradigms and their consequences

    Dev Med Child Neurol

    (2001)
  • V. Darsaklis et al.

    Predictive validity of Prechtl's method on the qualitative assessment of general movements: a systematic review of the evidence

    Dev Med Child Neurol

    (2011)
  • J.L.M. Bruggink et al.

    Early motor repertoire is related to level of self-mobility in children with cerebral palsy at school age

    Dev Med Child Neurol

    (2009)
  • F. Ferarri et al.

    Qualitative changes of general movements in preterm infants with brain lesions

    Early Hum Dev

    (1990)
  • F. Ferrari et al.

    Cramped synchronized general movements in preterm infants as an early marker for cerebral palsy

    Arch Pediatr Adolesc Med

    (2002)
  • M. Bosanquet et al.

    A systematic review of tests to predict cerebral palsy in young children

    Dev Med Child Neurol

    (2013)
  • E.G. Hamer et al.

    Assessment of specific characteristics of abnormal general movements: does it enhance the prediction of cerebral palsy?

    Dev Med Child Neurol

    (2011)
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