Posturology – multidisciplinary medical discipline

SUMMARY
Posturology studies the biomechanical and neurophysiological processes that allow the elaboration and active maintenance of diff erent body segments. It is a multidisciplinary method.
Postural pathology occurs when the centres integrating the central nervous system fail to achieve a synthesis of the information obtained by the receptors.
Postural deficiency syndrome (PDS) translates into a very varied symptomatology: musculoskeletal disorders, cognitive and perceptual disorders, disruptions of the motor scheme. The practice of posturology requires knowledge in two fi elds: neurophysiology and biomechanics. Before studying the posture of a child or adolescent, it is necessary to know the patient’s archaic refl exes and her/his psychomotor development.
Keywords: posturology, postural control, psychomotor development, rehabilitation

From birth to the end of adolescence, the acquisition and maturation of the postural system involve specific diagnostic and therapeutic aspects. The child’s postural and locomotor system becomes functional when the neural circuits involved in achieving the muscle tone are mature.
The maturation of these circuits is performed proximal-distally, so the postural-motor development stages will be [1]:
– Performing head control,
– Sitting posture,
– Walking on four limbs,
– Independent walking.
For postural control, the child uses cephalic (visual, vestibular) neurosensory information, that in the buccal sphere (deglutition, ventilation) and support information (podal, proprioceptive, articular and cutaneous).
Child posturology is a multidisciplinary approach that intervenes in a significant number of disorders concerning psychomotor and postural development. What are the specific aspects in child posturology?
1. Childhood and adolescence is the period of acquisition and maturation of the postural system during which the child is sensitive to internal or external disorders.
2. Postural treatment of the child and adolescent differs from that of the adult. It must adhere to the specific hierarchy of each ontogenetic stages of postural maturation [2].
Postural pathology occurs when the centres integrating the central nervous system cannot synthesize the information received from the various receptors. Postural deficiency syndrome (P.D.S.) has a very multifarious symptomatology:
a) Musculoskeletal disorders (headache, cervicalgia, lumbar pains, disc herniation, arthroses, repeated injuries of athletes);
b) Perceptual and cognitive disorders (dizziness, imbalances, disorders of spatial location, disorders concerning learning, attention and concentration);
c) Disorders of the motor scheme (dyspraxia, disorders of control and positioning of the body in space).
P.D.S. specific to the child:
– A newborn may have neurosensory receptor dysfunction related to torticollis or plagiocephaly. The consequence is a lack of harmonious integration of exteroceptive or proprioceptive sensory information. Thus, the anti-gravity posture, walking in four limbs or walking in orthostatism can be altered.
– Occasionally, P.D.S. occurs at a later stage of the child’s development, during schooling, when perceptual and proprioceptive disorders (dyslexia, attention and concentration disorders, lack of skill or repeated falls) occur.
– In adolescents, musculoskeletal forms, orthodontic, ventilatory or learning disorders may be described. In posturology, a multidisciplinary method, the following specialists can intervene: the rehabilitation doctor, the kinetotherapist, the ophthalmologist, the pedologist, the dentist, the otorhinolaryngologist, the orthophonist, the neurologist, the surgeon, the radiologist, the psychologist, the paediatrician, etc. For the postural approach of the child and adolescent, basic knowledge on archaic reflexes and psychomotor development is necessary. ARCHAIC REFLEXES should be well known by the kinetotherapist, especially regarding the age at which they must disappear: sucking reflex, automatic walking, Moro, grasping, symmetrical and asymmetrical tonic reflexes of the neck. These reflexes play an essential role in the realization of the motor schemes. Their non-integration contributes to difficulties in physical, emotional, cognitive activities.
PSYCHOMOTOR DEVELOPMENT OF THE CHILD: the newborn has a spontaneous anarchic, diffuse motriticity, with hypertonia flexion model of the limbs and the trunk. The development of tone and posture informs us about the neurological maturation of the infant [3]. The new born will be able to stabilize the head according to the actual movement of the body, but also due to the visual system [4]. At 2 months the difference in posture between the blind and the others can be observed [5]. During the different ontological stages, the body scheme is based on sensory information in interaction with the physical and social environment [6]. The muscular tone of the newborn will be apprehended depending on: the scarf manoeuvre, the measurement of the popliteal angle. At birth, motricity depends on the corticospinal system, whose maturation is descending. For the overall motricity, the motor acquisitions depend on the control of the axial tone that will allow the following: control of the head at 3 months, “sitting” posture at 7 months, orthostatism with support at 10-12 months, walking between 12-15 months, climbing the stairs with alternation at 30 months, maintaining the unipodal support for 5 seconds at 4 years, and walking along a line at 6 years. For fine motor skills (after the grasping reflex disappears), the infant develops the contact prehension at about 4 months and the voluntary one towards 5 months. Studies show that 4-10% of school-age children have psychomotor developmental disorders (in the absence of a motor, sensitive or sensory impairment or of brain injuries) and require a rehabilitation program [7]. The optimization of the motor development matures towards 18-19 years of age. Bourgeois has shown that the balance control process is immature at 7 years, it begins to develop at 14 years and is perfected at 18 [7]. Assaiante (1995 and 2010) identified the different ontogenetic stages that correspond to the periods of change in postural strategy in children and adolescents [8,9].
CONSEQUENCES OF ONTOGENETIC STAGE I (0-14 months)
– Any impairment of cephalic control will have major repercussions on postural and psychomotor development.
– Any restriction of the free articular movement of the cranio-cervical, cervico-dorsal junctions (plagiocephaly, torticollis) has major consequences on the postural and psychomotor development.
– The acquisition of walking on 4 limbs requires good mobility of cranio-cervical and cervicodorsal junctions [2].
– Postural development at this stage is descending, cephalo-caudal.

THE CONSEQUENCES OF THE ONTOGENETIC STAGE II (14 months-6 years)
– At this stage, the acquisition of walking takes place, which gradually presents a diminution of the support base.
– The postural organization being ascending at this age (caudal cephalic), there are often walking disorders.
– There is unrestricted mobility of the dorsolumbar and lumbosacral transition areas that acts as a pulley wheel between the trunk and the lower limbs.
– Any restriction of joint play in the dorsolumbar and lumbosacral areas has consequences on postural development [2].
TRANSITION PERIOD STAGE III (6-7 years)
– The child reorganizes the control of the cephalocaudal postural balance.
– S/he switches from the “head-trunk” block mode of operation to a dissociated mode [10].
– During this transitional period, the child partially and transiently loses control of peripheral vision in favour of vestibular control, thus balance strategies develop. – In the case of the pathological child (with dyspraxia, dyslexia, gait disorders), the transition period is delayed. CONSEQUENCES OF THE ONTOGENETIC STAGE IV (8-18-19 years)
– Transient neglect of proprioceptive information is noted.
– More efficient control of the degree of freedom of the cervical joints (i.e. descending organization of balance control).
– Increased visual contributions [11]
– Any impairment, especially of the visual or mandibular receptors, will influence postural and psychomotor development.
THE CONSEQUENCES OF THE ONTOGENETIC STAGE V (over 19 years)
– Approximately, the healthy adult relies on proprioceptive information (70%), 10% on sight and 20% on vestibular information.
– There is a complete “head-trunk” dissociation, selective control of the degrees of freedom in the cervical spine.
– Proprioceptive information is sufficient for the vertical orientation of the adult [2,12].
CONCLUSION
Any disturbance of the cephalic or supportive receptors in one of the ontogenetic stages has major repercussions on the postural and psychomotor development of the child, with the adoption in adulthood of an inappropriate postural strategy, associated with co-morbidities.

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