Developmental Dysplasia of the Hip (DDH) is a medical term for general instability, or looseness, of the hip joint. A number of different terms for hip dysplasia exist depending on severity and time of occurrence. In the case of DDH, the infant/child’s joint is otherwise typically developing except for the instability. Early diagnosis, prevention, and simple treatment are extremely important to prevent long term disability caused by DDH.
Hip Joint Anatomy
Within the womb, a baby spends the majority of their time tucked in the fetal position, in which both hips and knees are bent or flexed.
After birth, it takes several months for the joints to stretch out naturally. The hip joint is a ball (femoral head) and socket (acetabulum) joint held together by ligaments.
During the first few months of life the ball is more likely to be loose within the socket because babies are naturally flexible and because the edges of the socket are made of soft cartilage. If the hips are forced into an overstretched position too early, the ball is at risk of permanently deforming the edges of the cup shaped socket (hip dysplasia) or gradually slipping out of the socket altogether (hip dislocation).
Hip dysplasia or dislocation in babies is not typically painful so this may go undetected until the child begins to walk. The risk of hip dysplasia or dislocation is greatest in the first few months of life. By six months of age, most babies have nearly doubled in size, the hips are more developed and the ligaments are stronger, so are less susceptible to developing hip dysplasia.
Signs and Symptoms of DDH
Asymmetrical buttock creases can suggest hip dysplasia in infants, an ultrasound or x-ray study is necessary to confirm diagnosis.
2. Hip Click
Hip clicks or pops can sometimes suggest hip dysplasia but a snapping sound can also occur in healthy hips from developing ligaments in and around the hip joint.
3. Limited Range of Motion
Parents may have difficulty diapering because the hips cannot fully spread.
Pain is normally not present in infants and young children with hip dysplasia, but pain is the most common symptom of hip dysplasia during adolescence.
A painless but exaggerated waddling limp or leg length discrepancy are the most common findings indicative of hip dysplasia after learning to walk. If both hips are dislocated, then limping with marked swayback may become noticeable after the child starts walking.
The most unhealthy position for the hips during infancy is when the legs are held in extension with the hips and knees straight and the legs brought together, which is the opposite of the fetal position. The risk to the hips is greater when this unhealthy position is maintained for a long time.
The healthiest position for the hips is for the hips to fall or spread (naturally) apart to the side, with the thighs supported and the hips and knees bent. This position has been called the jockey position, straddle position, or frog position. Free movement of the hips without forcing them together promotes natural hip development.
Severity of DDH
Image courtesy of Canadian Orthopaedic Foundation
Hip dysplasia has a wide range of severity. In some children the ligaments around the hip joint are loose allowing the hip to subluxate. This is when the ball is no longer centered in the socket. Other times the ball is slightly or completely dislocated from the socket.
Unfortunately hip dysplasia cannot be prevented 100%. While the causes of hip dysplasia continue to be studied, here are some helpful tips to help prevent and reduce the risks of developing hip dysplasia.
Baby Swaddling & Hip Dysplasia
Improper swaddling may lead to developmental dysplasia of the hip. When in the womb the baby’s legs are in a fetal position with the legs bent up and across each other. Sudden straightening of the legs to a standing position can loosen the joints and damage the soft cartilage of the socket.
Many parents find that swaddling can provide comfort for fussy babies, reduce crying, and develop more settled sleep patterns. When babies are swaddled, care should be taken to swaddle properly so the baby is safe and healthy.
In order for swaddling to allow healthy hip development, the legs should be able to bend up and out at the hips. This position allows for natural development of the hip joints.
The baby’s legs should not be tightly wrapped straight down and pressed together. Swaddling infants with the hips and knees in an extended position may increase the risk of hip dysplasia and dislocation.
Baby Wearing & Hip Dysplasia
Proper infant hip position while babywearing is especially important because the period of time for babywearing is usually longer than baby transport. When proper hip position is maintained while babywearing, there may be substantial benefit for natural hip development. The Spread Squat position is recommended with the thighs spread around the caregiver’s torso and the hips bent so the knees are slightly higher than the buttocks or at the level of the buttocks with the thighs supported.
At this time the following products have been deemed “hip-healthy” by the International Hip Dysplasia Institute.
Best Swaddle Blankets
3. ERGO Swaddle
3. Moby Wrap
For more information about hip dysplasia visit the International Hip Dysplasia Institute. Thank you for allowing us to use your helpful images as reference.
Learn more about Dinosaur Physical Therapy!