Developmental_Dysplasia_of_the_Hip_Flashcards

Question 1

What is Developmental Dysplasia of the Hip (DDH)?

Answer 1

DDH, previously known as congenital dislocation of the hip, affects 1-3% of newborns and involves abnormal development of the hip joint.

Question 2

What are the risk factors for DDH?

Answer 2

Risk factors include female sex, breech presentation, positive family history, firstborn status, oligohydramnios, birth weight over 5 kg, and congenital calcaneovalgus foot deformity.

Question 3

What are the screening recommendations for DDH?

Answer 3

Screening with ultrasound is recommended for infants with a first-degree family history of hip problems, breech presentation at/after 36 weeks, or in multiple pregnancies. All infants undergo Barlow and Ortolani tests at newborn and six-week checks.

Question 4

How is DDH diagnosed?

Answer 4

DDH is diagnosed through clinical examination using the Barlow test (to dislocate) and Ortolani test (to relocate) the femoral head, checking for leg symmetry, knee level, and hip abduction. Ultrasound confirms diagnosis, or X-ray if older than 4.5 months.

Question 5

What is the management for DDH?

Answer 5

Management includes spontaneous stabilization by 3-6 weeks for most, use of Pavlik harness for children younger than 4-5 months, and possible surgery for older children.

Question 6

What is the first line of management for DDH in infants less than 6 months old?

Answer 6

Observation - Progress is monitored by repeat ultrasound or X-ray.

Question 7

What is the second line of management for DDH if observation is not sufficient?

Answer 7

The infant may be placed in a splint or Pavlik harness to keep the hip flexed and abducted - follow-up with x-ray at 6 months of age.

Question 8

What is the third line of management for DDH if conservative measures fail?

Answer 8

Surgery, specifically reduction with spica casting.

Question 9

When should an ultrasound scan be performed to check for DDH?

Answer 9

At 6 weeks in the following cases:

Breech presentation at 36 weeks gestation (regardless of presentation at delivery)
Breech delivery (including <36 weeks gestation)
Family history of DDH

Question 10

From what age is hip X-ray better than ultrasound for diagnosing DDH?

Answer 10

From 6 months onwards.

Question 11

What is the typical prognosis for most unstable hips in infants with DDH?

Answer 11

Most unstable hips will resolve spontaneously by 3-6 weeks.

Question 12

What is the preferred treatment for DDH in children younger than 4-5 months?

Answer 12

Pavlik harness.

Question 13

What might older children with DDH require?

Answer 13

Surgery.

Question 14

Which sex is at greater risk for DDH?

Answer 14

Female sex.

Question 15

summarise DDH

Answer 15

Developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) is gradually replacing the old term ‘congenital dislocation of the hip’ (CDH). It affects around 1-3% of newborns.

Risk factors
female sex: 6 times greater risk
breech presentation
positive family history
firstborn children
oligohydramnios
birth weight > 5 kg
congenital calcaneovalgus foot deformity

DDH is slightly more common in the left hip. Around 20% of cases are bilateral.

Screening for DDH
the following infants require a routine ultrasound examination
first-degree family history of hip problems in early life
breech presentation at or after 36 weeks gestation, irrespective of presentation at birth or mode of delivery
multiple pregnancy
all infants are screened at both the newborn check and also the six-week baby check using the Barlow and Ortolani tests

Clinical examination
Barlow test: attempts to dislocate an articulated femoral head
Ortolani test: attempts to relocate a dislocated femoral head
other important factors include:
symmetry of leg length
level of knees when hips and knees are bilaterally flexed
restricted abduction of the hip in flexion

Imaging
ultrasound is generally used to confirm the diagnosis if clinically suspected
however, if the infant is > 4.5 months then x-ray is the first line investigation

Management
most unstable hips will spontaneously stabilise by 3-6 weeks of age
Pavlik harness (dynamic flexion-abduction orthosis) in children younger than 4-5 months
older children may require surgery

Question 16

summarise management of DDH

Answer 16

 Seek specialist orthopaedic opinion
Management
 First line (<6 months old): Observation - Progress is monitored by repeat ultrasound or X-ray
 Second line: The infant may be placed in a splint or Pavlik harness to keep the hip flexed
and abducted - follow-up with x-ray at 6 months of age.
 Third line: Surgery if conservative measures fail (reduction with spica casting)
 Indications for ultrasound scan at 6 weeks to check for DDH:
o Breech presentation at 36/40 (regardless of presentation at delivery) o Breech delivery (including <36/40)
o Family history of DDH
 From 6 months onwards, hip X-ray is better than ultrasound
 Summary

Most unstable hips will resolve spontaneously by 3-6 weeks Pavlik harness in children younger than 4-5 months
Older children may require surgery
Female sex at greater risk

Question 17

A 38-year-old woman who has a 3-month old baby comes to see you as her friend’s baby has had a hip ultrasound and she believes it is unfair that this has not been offered to her child. You explain to her that only babies who have risk factors for hip dysplasia are offered an ultrasound.

Which one of the following is a risk factor for hip dysplasia?

Forceps delivery
Maternal age greater than 40 years
Breech presentation
Ventouse delivery
Maternal obesity

Answer 17

Breech presentation

Breech presentation is a risk factor for developmental dysplasia of the hip

Ultrasound screening for developmental dysplasia of the hip (DDH) is done at 6 weeks of age for newborns with specific risk factors.

These include

A first-degree family history of hip problems in early life.
Breech presentation at or after 36 weeks gestation (irrespective of presentation at delivery)
Breech presentation at delivery if this is earlier than 36 weeks.

Furthermore, those children found to have a positive Barlow or Ortolani test are sent for a hip ultrasound to rule out DDH.

Question 18

A 3-month-old baby girl is diagnosed as having developmental dysplasia of the left hip following an ultrasound examination. Clinical examination of the hip was abnormal at birth. What treatment is she most likely to be given?

Double nappies
Pavlik harness (dynamic flexion-abduction orthosis)
Spica cast in flexion and abduction
Re-scan at 6 months
Surgery

Answer 18

The correct answer is Pavlik harness (dynamic flexion-abduction orthosis). The Pavlik harness is the first-line treatment for developmental dysplasia of the hip (DDH) in infants under six months of age, particularly when diagnosed early as in this case. The harness holds the baby’s hips in an optimal position for joint and socket development, allowing natural growth to correct the dysplasia. It has a high success rate with few complications if used correctly.

Discussing the incorrect answers:

Double nappies are not a recommended treatment for DDH. This outdated method was thought to hold the hips in a beneficial position, but it does not provide sufficient stability or alignment for proper hip joint development.

Spica cast in flexion and abduction is typically used when initial treatment with a Pavlik harness has failed or if the child is older at diagnosis (usually over six months). In this case, since the baby girl is only three months old and no previous treatment has been attempted, this would not be the first choice of treatment.

A Re-scan at 6 months would not be appropriate without any initial intervention. DDH can lead to long-term problems such as limping, hip pain, and osteoarthritis if left untreated. Therefore, delaying treatment could result in poorer outcomes.

Finally, Surgery is usually reserved for cases where non-surgical treatments have failed or if the condition is diagnosed late (typically after walking age). As our patient is only three months old and there’s no indication that non-surgical interventions won’t work, surgery would not be considered at this stage.

Question 19

A doctor is undertaking a newborn baby check and discovers that the hips are Barlow and Ortolani test positive.

Which of the following is most likely to apply to this child?

Female
Caesarean section birth
Low birth weight
Cephalic presentation
Polyhydramnios

Answer 19

Female

Female sex is a risk factor for developmental dysplasia of hip

Barlow and Ortolani tests are positive in developmental dysplasia of the hip. Of the answers listed, the only risk factor for DDH is being female. C-Section birth is not relevant. The opposite of the remaining answers are risk factors for DDH: high birth weight, breech presentation and oligohydramnios.

Question 20

A six-week-old baby has been brought in by his mother after she is concerned about his movement. He is diagnosed as having developmental dysplasia of the hip on ultrasound.

Which statement is correct regarding the management of developmental dysplasia of the hip?

Avascular necrosis and temporary femoral nerve palsy are potential complications of splinting

A Pavlik harness can be applied at any age

Prognosis is not affected by the age at diagnosis

Recovery following closed reduction is usually complete after four weeks

Surgical reduction is always indicated

Answer 20

Explanation
A
Avascular necrosis and temporary femoral nerve palsy are potential complications of splinting

Pavlik harness splinting is not without complications but can be less invasive than surgical correction, depending on the child’s age. If the child is under six months, the splint is usually tried first, and if there is no response, the child may go on to have surgery.

Avascular necrosis (AVN) and femoral nerve palsy both are considered potential risk factors for splinting used for DDH. In the context of DDH and hip splinting, AVN can occur if the splint or brace exerts excessive pressure on the femoral head, and with splinting, pressure from the splint or brace can sometimes affect the femoral nerve and cause temporary nerve dysfunction.

D
Recovery following closed reduction is usually complete after four weeks

Following reduction surgery, children usually need a plaster cast or a reduction brace for three to four months.

B
A Pavlik harness can be applied at any age

Pavlik harnesses are contraindicated in children over six months old or with an irreducible hip. In children with a delayed diagnosis or an irreducible hip, surgery is the only treatment option available.

C
Prognosis is not affected by the age at diagnosis

The greater the child’s age at diagnosis, the more likely they will need a more extensive corrective procedure.

E
Surgical reduction is always indicated

Surgery is reserved for children in whom a Pavlik harness is not indicated or has not worked. It may also be indicated for children who were too old at presentation to try a harness or have an irreducible hip.

Question 21

An overweight 13-year-old boy presents with left groin pain that has been getting progressively worse over the last few weeks, to the point that he is now unable to bear weight on his left leg. He has a Trendelenburg gait and, although there is no pain on palpation or any obvious swelling on examination, there is obligatory external rotation during passive flexion of the hip and limited range of movement, especially in internal rotation, abduction and flexion of the hip. Anteroposterior (AP) and frog-leg lateral radiographs of the hip and pelvis show that the Klein’s line does not intersect the femoral head.

What is the most appropriate treatment option for him?

Observation and follow-up, reassuring his parents that these are growing pains which will improve

Hip spica casting and no weight-bearing for 4 weeks
Limited weight-bearing on crutches for 2 weeks and analgesia
Hip arthroscopy and labral repair
In situ screw fixation

Answer 21

Explanation
E
In situ screw fixation
The history and examination findings are suggestive of SCFE, for which the patient has several risk factors. The management of SCFE involves in situ screw fixation, usually performed percutaneously.

A
Observation and follow-up, reassuring his parents that these are growing pains which will improve

The history and examination findings do not suggest growing pains. Reassurance is not appropriate at this stage.

B
Hip spica casting and no weight-bearing for 4 weeks
Hip spica casts are usually used in the treatment of congenital hip dislocations in infants. They have no role in the treatment of slipped capital femoral epiphysis (SCFE).

C
Limited weight-bearing on crutches for 2 weeks and analgesia
This will not resolve the patient’s SCFE.

D
Hip arthroscopy and labral repair
Hip arthroscopy and labral repair have no role in the management of SCFE.

Question 22

A five-year-old male walks with a limp due to right hip pain, relieved by rest and made worse by walking or standing. His vital signs are normal. The Trendelenburg sign presents when he stands on his right leg. X-rays reveal periarticular right hip swelling in soft tissue. A bone scan reveals reduced activity in the anterolateral right capital femoral epiphysis.

What is the most likely diagnosis?

A slipped capital femoral epiphysis
Legg-Calvé-Perthes disease
Septic arthritis
Epiphyseal dysplasia
Synovitis

Answer 22

Explanation
B
Legg-Calvé-Perthes disease
Legg–Calvé–Perthes disease is a self-limiting condition caused by compromised blood flow to the femoral head. Its exact cause is unclear but may relate to developmental changes in the hip’s blood supply. The disease typically occurs between ages four and nine when retinacular arteries are crucial for femoral head blood supply. The formation of the epiphyseal plate and ossification at puberty further alters blood flow. The patient also exhibits synovitis and hip joint effusion, indicated by soft tissue swelling around the hip joint.

A
A slipped capital femoral epiphysis
A slipped capital femoral epiphysis would be obvious on hip radiography. The radiological findings, in this case, do not suggest this diagnosis.

C
Septic arthritis
Septic arthritis would cause features of a systemic inflammatory response. The normal vital signs in this scenario indicate no systemic inflammatory process occurring.

D
Epiphyseal dysplasia
Epiphyseal dysplasia, a congenital defect, would most likely present when the child started to walk.

E
Synovitis
There is radiological evidence of synovitis in this scenario. However, synovitis is a non-specific sign and not a specific diagnosis.