Locomotor development of the newborn baby and peculiarities of premature infants
Before reaching independent walking and free playing with hands, the newborn (the term one or the premature one) passes through certain stages of its neuro-motor development, both in the common (gross) motor skills, and in the fine manipulation (fine motor skills) with upper limbs.
Many factors influence the development and shaping of the locomotor system in the newborn and the infant, as well as on the pattern of the cross-legged walking in humans. Such factors include:
- Primitive reflexes and mechanisms residing and disappearing, which affect the state of the muscular tone. Slowing their extinction is associated with negative changes in muscle tone and delayed motor development.
- Reactions of straightening against gravity and related support planes.
- Taking a different position and related reference points and planes
- Stimulation of age-adequate balancing effects, ensuring the retention of age-designated positions.
- Activation of certain age-determined moves, forward movement, and movements to the side
- Turn on different planes of movement, specific to certain age and the relevant to them balance reactions.
- Adoption of the center of gravity movement along different planes.
- The status of the muscle tone, activation of the muscle activity and directions of the movements.
- Presence or absence of inner need to move.
- Formation and development of a body scheme and the related orientation in space.
- Acquisition and development of sensorimotor experience.
K. Bobath says "balancing the position of the body is achieved by working the muscles of the infant against the action of gravity".
The acquisition of its own sensorimotor experience (SME) is extremely important for the proper nerve-motor development of the infant. It is acquired gradually and independently, the child should be left only to communicate with the outside world according to its age capabilities and achieved motor skills. SME is based on the independent muscle activity of the infant against gravity.
The infant, depending on its calendar age, uses planes of various sizes and various reference points, both on belly position and lying on his back. The used planes and reference points change in a certain way with the growth of the infant until independent walking is achieved.
- For example, the support of the newborn, lying on its belly, is entirely on the whole abdomen and the forearms;
- In the first quarter, the support gradually and smoothly reduces in size and is located in the forearms and pelvis (symmetrical elbow support);
- In the second quarter, in the same way, the support plane gradually decreases and locates in the palms and thighs (palms support), and, in addition to the sagittal plane, the center of gravity begins to move also in the frontal plane (single elbow support – a snatch from a symmetrical elbow support);
- In the third quarter, the support continues gradually to decrease and is located only in the hands and knees (a four-pillar standing), with the appearance of moving forward (creeping provided by three-pillar standing, as the center of gravity moves already in sagittal, frontal and transverse planes);
- In the fourth quarter, from creeping through knee standing and half-kneeling, the child takes a two-foot support, while mastering single-foot support through sagittal walking on furniture and placing hands, is related to the emergence of independent walking.
In the process of self-straightening and toddling, the infant uses different contact surfaces and points (abdomen, pelvis, hips, feet and forearms, elbows and palms), by which independently, but gradually and smoothly, controls the center of gravity, together with this building a scheme of its body that serves as orientation in space. The SME undergoes a smooth and gradual development, related to the maturation of the brain, which by itself is an accumulation of information through trial and error.
Development of motor skills
From a prone position (baby lying on its belly)
Mapping gross motor skills of calendar age:
- 1.5 months - forearm support
- 3 months - symmetrical elbow support
- 4.5 months - a single elbow support
- 6 months - palm support
- 7.5 months - four-pillar standing
- 9 months - crawling, standing on his knees, straightening on the vertical axis
- 10,5 months - creeping on the vertical axis, sideways walking
- 12 months - walking (broad-based - "Winnie walking")
- 15 months - self-straightening up from the floor ("a dog walk")
- 18 months - self-straightening up from the floor through half-kneeling, going up stairs with one hand support
From a supine position (the baby lying on its back)
Mapping gross and fine motor skills at calendar age:
- 1.5 months - asymmetric position "fencer", non-targeted movements of the hands
- 3 months - fixates and follows with eyes, a centered position of the hands
- 4.5 months - turning to a side position; visual-motor coordination: hand-mouth-hand, targeted snatch behind the midline of the body, the hand takes the gripping function, start of stereognosis;
- 6 months - turning from back to belly; "key grip" - thumb to the side of the flexed index finger;
- 7.5 months - oblique seating, side seating; visual-motor coordination, hand-foot-mouth; "tweezers grip" - a contact between the index finger and the thumb;
- 9 months - seating in the long plane (with straight knees); "pincer grip" - touching the tips of the index finger and the thumb;
- 10.5 months - an isolated stretch of the index finger
Some specific features of premature infants
The maturation of all organs and systems, including central nervous system (CNS) and muscle apparatus in preterm infants is not completed. The immaturity of the nervous system can be characterized by incomplete differentiation of the brain substance, the insufficient development of the responses of the vestibular system, the lower degree of myelinization of the main conduction fibres, the lower overall muscle tone, the predominance of the tone of the extensor (expandable) muscles, and a lack of primitive reflexes. The immature muscle apparatus most often represents less muscular force, and in particular of the flexor (shrinking) muscles, which develop in full force and endurance in the last 8-12 weeks and are essential to overcoming the gravity by turning from abdominal or back position of the newborn.
The aforementioned CNS abnormalities in premature infants are sometimes combined with asphyxia (Apgar 6 and less) and / or various types and degree of cerebral hemorrhage, which causes "oxygen starvation" of the brain, and are responsible for the following possible problems in neuro-motor development of the premature child.
Does the child need rehabilitation and if YES, what kind?
1. Not every preterm infants needs a specialized rehabilitation, but it is necessary the baby to be followed up by a doctor, specialist in pediatric neurology and / or by a doctor, specializing in physical and rehabilitation medicine (FRM) with experience in children neurorehabilitation, who could make the necessary assessment of inclusion specialized stimulation of the motor development.
The most accurate in evaluating the motor development of the child is the combined neuro-kinesiology examination, which includes testing the following:
- Spontaneous motility (what the child can perform alone);
- Testing of tendon and periosteal reflexes, as well as dynamics (presence and disappearance) of primitive reflexes and mechanisms
- Provoked motility (stimulation of the vestibular system of the baby by certain movements in space, which trigger activation of certain muscle groups and chains, such as by the type of muscle activation and the complex of movements, "the correctness of the brain commandment" can be assessed).
2. Do not trust the medical or healthcare professionals who soothe you that "because the child is premature, it could be lagging behind in the neuro-motor development." We must recalculate the calendar age of the child including the prematurity period by estimating the so-called "corrected age" of the newborn. Once the corrected age is calculated, the baby should follow the respective stages in its motor development. (e.g. if the baby is 6 calendar months, and was born three months earlier, then his "corrected age" is three months, and the motor requirements must meet those of a three-month old baby), and if it does not cover them, a specialized medical care should be sought.
3. Like any term newborn, the premature baby also needs a massage and passive movements during the first few months until the moment the child begins to turn to the side by itself (4.5 months corrected age).
4. However, stimulating hands and feet that must be excluded from the massage as those are areas that unlock very primitive reflexes and mechanisms, which being continuously activated in one immature and / or traumatized CNS could lead to some undesirable deviations in the neuro- motor development of the premature baby.
5. Newborn premature babies especially, apart from the massage and the passive movements, also need specific "embryonic" positioning when carried by the parent and / or when awake. The embryonic positioning at carrying is as follows: the baby is put with its back to the parent between the carrying arm and his body, the inner leg of the child is fixed by the carrying arm of the parent and the outer leg astride it, the head is located between the biceps of the carrying arm of the parent and his rib muscle. In this position, the child feels support the from the back and from the sides along the whole body, much like to the position during the mother's pregnancy. This position gives peace and antigravity facilitation for the child, reduces the strength of the cervical and posterior thigh extensors of the child, which in premature babies have expressed precedence that may lead to delays in the function of the cervical and ventral flexors and from there to a delay in the motor development of the premature baby.
Embryonic "nest type" positioning when awaken and lying on the back: After the first week, the premature baby should be allowed to stay awake lying both on the back and on the belly. Due to the prevalence of the strength of the extensor muscles (extensors) lying on hits, that being a reflex (labyrinth tonic reflex), and due to immaturity of both the central nervous system and the muscles, it is recommended the child to be positioned in a fetal "type nest" position. Such nests are recommended to be used both in the NICU and at home until the age of 3.5 - 4 months, when the attempts of the baby to turn to the side start to appear.
6. While wishing to enjoy our child and to play with it (swinging like the airplane; giving the finger to be gripped by the palm; tossing the child like an elevator: supporting it at the armpits to stand upright or step), we provoke an immature vestibular system and immature muscle groups and chains, which are not ready to bear the corresponding burden, therefore we unlock inadequate motor responses, which often deform more or less the motor development of the baby or block it partially.
7. If you notice any asymmetry in the motion of the lower or upper limbs, you should seek specialized medical consultation as fast as possible: a pediatric neurologist and / or specialist in physical and rehabilitation medicine with expertise in child neuro-rehabilitation.
8. The specialized rehabilitation in neonates and infants includes stimulation of movements by various methods, some of which are applied in our country. The specialist pediatric neuro-rehabilitation (neuro-stimulation) is carried out in specialized hospitals by trained physicians - specialists in physical and rehabilitation medicine and therapists (physical therapists, physiotherapists, occupational therapists). The massage and the passive movements in present retardation or "deformation" of the motor development have no significant therapeutic value and their application represents a loss of rehabilitation time. Some pediatricians, pediatric neurologists and therapists suggest to the parents to use stimulation of some movements of the newborn and the baby by activating primitive reflexes and mechanisms (foothold and creeping - Bauer reflex; contraction of the fingers - gripping reflex of Robinson; contraction of the toes - plantar gripping reflex; spreading of toes - Babinski reflex; sharp hands unfolding and embracing - reflex of Moreau; horizontally holding the chest in the air for stretching the head - Landau reflex; and others), leading to the activation and retention of the activity of the wrong muscle groups and chains, which in immature central nervous system of the premature newborns, easily leads to distortion or delay of the neuro-motor development of the baby and increased risk of fixing these incorrect motor patterns in time and shaping the clinical picture of cerebral palsy.