Congenital hip dislocation is an alteration in the relationship between the cup (joint cavity) and the head of the femur. It refers to a loss of contact between the surfaces of these two bony structures at birth. Congenital hip dislocation is the most severe stage of developmental dysplasia of the hip.
It is usually diagnosed during the first six months of life by physical examination of the baby with maneuvers called Ortolani and Barlow. The presence of asymmetry in the folds of the thighs and buttocks or the difference in length between the lower limbs can also make us suspicious.
Incidence and prognosis
Its incidence is between 1 and 6 of every 1,000 newborns, and if it is not treated promptly, it can cause severe disability. However, correct treatment in the first weeks of life with a Pavlik harness manages to return anatomical and functional normality to the hips, which were dislocated entirely in most cases, so that an accurate diagnosis followed by early treatment is decisive in these cases. Kids.
This anomaly is caused, in most cases, by a partial arrest of intrauterine growth in the hip region. If the alteration occurs before the third month of pregnancy, the hip appears already dislocated at birth (embryonal-type dislocation).
What is developmental dysplasia of the hip?
Developmental dysplasia of the hip refers to a broad spectrum of pathological alterations that include: dislocation, subluxation, and dysplasia, which can appear from birth to the development of walking.
We have three types of hip dysplasia:
Teratological dysplasia: these are severe dysplasias that occur during the embryonic phase, are irreducible and are associated with other essential alterations, such as myelomeningocele. Developmental dysplasia of the hip: occurs during perinatal life, may be present at birth, is not usually associated with syndromes, and has associated risk factors. Infantile and adolescent dysplasia: occurs when there is a deformity of the proximal femur and the acetabulum, but the joint is reduced.
Congenital Hip Dislocation in Babies: Baby Lying Down with Legs Spread with Hip Problems
why it occurs
There are three main risk factors:
Female sex: the estrogens produced in the female fetus are related to the increase in relaxin, a substance that causes an increase in ligamentous laxity. Breech presentation: presenting greater risk if associated with knee extension (this position is called pure breech). Family history: if there is an affected sibling, the risk is 6%; if one of the parents is involved, it is 12%, and 36% if a sibling and one of the parents are affected.
How is it diagnosed?
If the baby has at least two of these factors, or the physical examination is pathological, an ultrasound of the hips after birth is recommended. Prematurity appears to be a protective factor.
In the case of a routine examination associated with risk factors, it should be performed after four weeks of life. It is not recommended before this age due to physiological hyperlaxity, which is associated with a high rate of false positives.
Hip ultrasound should be performed in experienced centers since it is a radiologist-dependent test. From four to six months of age, when ossification of the nuclei of the head of the femur occurs, the examination of choice is radiography of the hips.
The anomaly of the imaging test requires the assessment of a child traumatologist, like the ones you can find in the MAPFRE Salud insurance medical chart, to apply the appropriate orthopedic treatment. The treatment of choice is the Pavlik harness or abduction splint. This is placed in cases of reducible hips in babies less than six months of age.
The harness must be checked and placed weekly by the traumatologist, who will check that the femoral head is well reduced. If a hip reduction is not achieved within three weeks, treatment will be stopped. If effective, this harness should be maintained for between three and four months, gradually removing it.
Late or refractory treatment to this harness requires more complex interventions and not always good results.
Even if the parameters of the hip have normalized, these children may develop late dysplasia, which is why follow-up is necessary until skeletal maturation.
Neonatal screening for congenital hip dislocation
Nowadays, universal screening is carried out on all newborns to detect dislocation early. Congenital hip disease. It consists of the physical examination of the baby’s hips by his pediatrician in all check-ups from the neonatal period to six months. Despite its systematic performance in all centers and all children, it has not been possible to solve this problem entirely since the physical examination depends on the experience of the professional. In addition, in 50% of cases in which a hip is dislocated, it cannot be detected by physical examination, the failure rate being even higher when the dislocation is bilateral.
In countries where universal screening for hip dysplasia has been implemented by law (Germany, Austria, Switzerland…) employing an ultrasound scan of the newborn, the number of dislocated hips that require surgical treatment has been reduced to practically 0. It has also managed to reduce by 1/3 the total cost attributable to the disease process.
What you should know…
This anomaly is caused, in most cases, by a partial arrest of intrauterine growth in the hip region. The treatment of choice is the Pavlik harness or abduction splint. This is placed in cases of reducible hips in babies less than six months of age. In countries where universal screening for hip dysplasia has been implemented by law (Germany, Austria, Switzerland...) using an ultrasound scan of the newborn, the number of dislocated hips that require surgical treatment has been reduced to practically 0.