THE ROLE OF THE EYES IN POSTURAL BALANCE

The ocular sensor is one of the 6 sensory sensors of the upright postural system. So the eyes have a central role in posture control.

In posturologie , the balance and good posture of an individual translates by the alignment of the feet on the ground and the eyes on the horizon. If these two conditions are not met, the body is still able to move since the other sensors compensate. Nevertheless, postural imbalances appear and cause pain and other constraining symptoms in daily life.

Hence the need to monitor the proper functioning and good health of the eyes and particularly of the oculomotor muscles.

The importance of the eyes in maintaining posture

The double function of the eyes

Organ of sight, the eye has a dual role within the postural system: it is both an exosensor and an endosensor.

On the one hand, the retina (exosensor) receives information from outside the body so that man observes his environment and orients himself in space.

On the other hand, the oculomotor muscles (endosensor) allow the eyes to move. They also transmit to the brain information concerning the body in relation to its environment, and more particularly the position adopted by the eyes in relation to space. However, to see correctly, the head must be able to follow the movement of the eyes. Thus, the oculomotor muscles are associated with the muscles of the neck: this is the oculo-cephalyric reflex. These two muscle groups work in coordination. Together, they provide the brain with information about the behavior of the eyes in relation to its environment and the target: Are the eyes and head moving to follow the target? Is the target stationary or moving?

Thanks to this dual function, the eyes play an important role in postural maintenance.

Oculomotor imbalances and their impact on posture

As with any other sensor in the system, if the eyes, and more particularly the oculomotor muscles, suffer from a deficiency or an imbalance, the system compensates for the lack. This is how man can always stand and move.

The operation is simple: if the oculomotor muscles are not working properly, the eyes cannot move as they should. In this case, the information that the muscles transmit to the brain is distorted. To avoid this, the brain rectifies the problem by adapting the posture of the individual as needed. Instead of the eyes moving, other areas of the body move to compensate. Obviously, in this case, the cervical area is the first to be affected. Indeed, the head will have to make the movement or position itself in such a way as to compensate for the movements that the oculomotor muscles cannot make. However, in the long term, postural disorders appear because the position of the head, and therefore of the rest of the body, is no longer natural. And even if the body does not directly feel the weakness of the eye muscles, the poor posture causes pain that can quickly handicap daily life.

There are different types of oculomotor imbalances and each leads to various postural changes and disorders:

  • – A heterophoria: it is a deviation of the eyeballs. Caused by weakness of the oculomotor muscles, eye movement is no longer symmetrical and the visual axis is no longer aligned. Unlike a strabismus, this deviation is not permanent and does not affect the eye at rest.

There are several heterophoria depending on the deviation:

  • exophoria (article link “The postural impact of ocular convergence insufficiency) when the deviation is divergent
  • esophoria when it is convergent
  • hyperphoria when the person looks up
  • hypophoria when looking down.

According to heterophoria, certain situations will force the person to maintain a posture that is not natural and that will cause pain. This is how a person who suffers from convergence insufficiency bends down and brings his head closer as soon as he has to see up close (reading, using screens, etc.). We therefore understand that in the medium to long term, this will cause him back and neck pain.

  • spectacles whose correction is no longer suitable: spectacle lenses are made so that the necessary correction is facing the pupils. If this is no longer the case, the individual naturally orients his head in order to regain a comfortable view.
  • A postural disorder affecting another sensory sensor: when the eyes are no longer aligned with the horizon, once again, the head and the oculomotor muscles compensate. For example, an individual who does not stand straight because he has one leg shorter than the other (even if this is not visible to the naked eye or constraining for the person), tilts his head so that his eyes remain aligned. Even the smallest deviation can cause an imbalance in posture.

These dysfunctions in the eyes therefore reveal postural imbalances which cause pain and in various terms symptoms:

  • – Head rotation
  • – Back and neck pain: neck pain, sciatica, lumbago, etc.
  • – Headaches
  • – Visuospatial dyspraxia, concentration disorder
  • – Dizziness, nausea
  • – Fatigue visual
  • – General tiredness
  • – …

Thus, it is important to detect the possible deficiency of the ocular sensor, not only to relieve certain pains but especially to avoid postural disorders which will have more serious consequences.

Detection of eye sensor asynchrony

Several tests exist to detect an oculomotor disorder such as the test of ocular motricity or the convergence test. Generally, after detection, the disorder is treated through orthoptic sessions (re-education of the eye muscles). Nevertheless, these tests do not make it possible to understand the origin of the problem. However, if the origin of the disorder comes from a postural imbalance and therefore from another sensor, this solution will not be sustainable.

If a health professional diagnoses you with an imbalance of the oculomotor muscles, we advise you to do a postural check-up < /strong> with a doctor specializing in posturology. An orthoptist can be specialized in posturology, as is the case with many other doctors (podiatrist, osteopath, dentist, ENT, ophthalmologist, general practitioner, physiotherapist, etc.). The postural assessment is an examination that makes it possible to analyze the whole posture and each sensory sensor using several tests and medical devices in order to detect where the postural disorder comes from.

La méthode de Maddox

Among the tests carried out during the assessment, the Maddox test is the one which allows you to check the eye sensor. This method consists of looking at a point of light placed 2 meters away. In front of one open eye is placed the Maddox wand (composed of a red lens with parallel lines), the other eye remains open and uncovered. Thus, the uncovered eye sees the luminous point while the other sees a horizontal or vertical luminous line depending on the position of the wand. This exam is done on both eyes. If the line passes over the luminous point, the eyes do not present any asynchrony, we say that there is orthophoria (horizontal or vertical). However, if the line is offset from the point, there is heterophoria. And the doctor is able to determine which one based on what the patient sees.

Thus, the Maddox method makes it possible to diagnose the different types of heterophoria as shown in the image.

However, if the disorder is caused by another sensor, the other postural assessment tests will make it possible to determine which is in question.

Les solutions

After diagnosing the disorder and its origin, the practitioner is able to offer his patient the appropriate treatment. Generally, heterophoria is treated with orthoptic sessions. In addition to the re-education of the oculomotor muscles, some individuals are prescribed osteopathy sessions. It is generally to relieve or even treat the postural imbalances caused by the oculomotor disorder.

In the event that another sensor is dysfunctional, the doctor will redirect the patient to the appropriate healthcare professional.

Likewise if the bad posture comes from eyeglasses. In this situation, this is easily detectable by the posturologist, especially with the vertical bar test. Strikethrough.