Hip Health
By Ina Joshi, DPT and Tara Liddle, DPT
Developmental Hip Dysplasia, also known as Congenital Hip Dislocation, is a common diagnosis in infancy.
Due to space limitations in the womb, babies tend to grow in a tucked position, called physiologic flexion. Over time, the flexed position leads to hip flexor and external rotator tightness, which is why we see newborns stay in a flexed position shortly after birth. As the infant spends more time out of the womb, gravity, positioning, and active movement help the legs straighten out.
Dysplasia occurs when the acetabulum is more shallow than it should be. When the hip joint is shallow, the chances of subluxation or dislocating the hip is higher.
Hip dysplasia may be developmental, with no known exact cause. There is also a genetic component to the issue; having a parent or sibling with the diagnosis increases the likelihood of being born with hip dysplasia. Breech positioning may also lead to hip instability and dysplasia due to increased pressure on the joints and ligaments.
Developmental hip dysplasia is a general instability, or looseness, of the hip joint. 1 in 100 infants are treated for hip dysplasia, and 1 in 500 infants are born with completely dislocated hips. Females are 4-5 times more likely to have hip dysplasia than males. The greater incidence in females may be due to higher ligamentous laxity in girls than boys. Infants born with fixed foot deformities or torticollis are more likely to have hip dysplasia as well. About 60 percent of unstable newborn hips spontaneously correct within the first two to four weeks after birth.
Newborn checkups help with early identification. X-rays are unreliable until six to eight weeks of age. Positioning after birth is the most preventive strategy for hip health. The safest position for an infant’s legs is one they naturally fall into; hips flexed, rotated outward, and spread apart. The goal of treatment ranges from observation to wearing a harness. If left untreated, cartilaginous, muscular, and bony changes may occur, leading to significant issues in later development. In severe or untreated cases, surgical intervention may be necessary to tighten the ligaments and muscles surrounding the hip joint.
It is essential to check positions in carriers, car seats, and while swaddling for safety. When swaddling or using a carrier, make sure the baby is in a hip healthy position. The least healthy position is when the hips and knees are straight with the legs together.
If you have any questions about positioning, please feel free to reach out!