The normal human head tends to be straight, whether gazing at a distant object or reading a book, newspaper or magazine, the line of sight always points forward and the head remains straight. If the gaze target is not directly in front of the observer, beyond the practical gaze field of view (13 degrees), the head will normally turn with it. If the gaze target is too far from the frontal field of vision, the body will also turn to keep the head straight. For various reasons, the baby’s head tilts to one side, commonly known as crooked head, crooked neck, slant neck. I. Causes of lopsided neck 1. The most common one is surgical lopsided neck. For example, abnormal muscles on one side of the neck, the most common ones are contracture of the sternocleidomastoid muscle, or cervical hemivertebrae, cervical tuberculosis, atlantoaxial subluxation, etc. 2. The second is ocular strabismus. The cause is mainly strabismus. Patients with strabismus often show abnormal head position, which can avoid diplopia and achieve binocular fusion function. 2. Definition and significance of ophthalmic strabismus Because the abnormal head position caused by strabismus is often located in a compensatory position, that is, when the head is tilted to this position, it has a compensatory effect, so it is called compensatory head position, or ophthalmic strabismus. The compensatory head position chosen by the patient is often the optimal position. By optimal position, we mean that the angle of head deviation is minimal and causes the least inconvenience to the patient. The abnormal head position exactly compensates for the defective eye movements, relaxes the paralytic muscles, and keeps the visual axis of both eyes in balance. The direction of the skewed head position depends on the paralytic muscle. Generally, the head position is taken to avoid the direction of the paralytic muscle, and the vision is directed to the field of vision opposite to that of the paralytic muscle. There are many causes of ocular strabismus, such as paralytic strabismus, idiopathic nystagmus, monocular profound amblyopia (abnormal head position is obvious when reading), mechanical factors limiting eye movements (such as retrobulbar syndrome, fixed strabismus, orbital wall fracture, etc.), ptosis, A-V syndrome, oblique axis astigmatism, etc. IV. Manifestations of ophthalmic strabismus Ophthalmic strabismus caused by paralytic strabismus is the most common. Among them, superior oblique muscle paralysis is the most common. The main manifestation of this disease is that the two eyes are one low and one high, but because the degree is small, we usually cannot see it with the naked eye, and the main manifestation is the tilted head, because when people do not have strabismus normally, the two eyes are parallel and are very positive, and at this time the two eyes see objects that can be fused into one and gathered in one point. If a child has congenital paralytic strabismus, there is a problem with the eyes, one is high and the other is low, so the child’s eyes appear to have two images, one high and one low, so the child sometimes sees his mother as two mothers, which makes him very uncomfortable. By tilting the head to one side, the two eyes become parallel and the child sees one, so this head tilt is to correct the diplopia caused by the strabismus. If you set the head right after, there will be two mothers again, and this time it is not possible to distinguish which one is real.