Diagnosis
The diagnosis in the infant can be made by means of an ultrasound examination (sonography) of the hip. On the one hand, this method is very reliable, and on the other hand, unlike X-ray or CT (computed tomography), it is completely free of radiation exposure, which should be avoided especially in children. Sonography is prescribed as a screening (early detection examination) for the U2 or U3 preventive examination.
In this way, the affected children are detected very early, which is essential for effective therapy and minimization of later consequential damage. The ultrasound image is used to differentiate between different stages of the disease (according to Graf).
- Grade I describes a normally shaped acetabulum
- Grade II describes a pathological dysplasia
- From grade III on, there is an additional dislocation of the femoral head (the femoral head no longer sits correctly in the socket)
- Grade IV describes a dysplastic hip with complete dislocation.
Therapy
Hip dysplasia must be treated in any case. Which procedure is indicated depends on the stage of the disease. A Graf II hip is treated by means of a so-called Tübingen flexion orthosis or a spreading plaster cast.
The principle here is that the femoral head is centered in the acetabulum (i.e. pressed into the socket) by a certain fixed position of the affected leg (flexion and spreading), which leads to stimulation of acetabular growth in small children. The aim is therefore to ensure that the acetabulum grows in such a way that it better accommodates the femoral head. From stage Graf III onwards, such a treatment is no longer sufficient; here the femoral head must be reduced (i.e. re-centered in the acetabulum).
Such a reduction can usually be performed “closed” (i.e. without open surgery), but can take several weeks. The child must then wear a plaster cast (usually the so-called fat-white plaster) for a few weeks and undergo regular sonographic checks.Here, too, a splint such as the Tübingen Hip Flexion Splint is used afterwards, which must be worn until healing is complete. If there is no improvement after 2-5 years, surgery must be performed. There are several procedures to choose from, all of them so-called osteotomies (i.e. cutting through bone parts of the hip or femoral head with subsequent rotation and reattachment), such as the Salter osteotomy or acetabuloplasty.
