DDH assesment in newborns screening.pptx

Ddh screening in newborns

1. Developmental Dysplasia of Hip SEMINAR BY DR.GNANAVELU INJETI PARAMITHA CHILDREN’S HOSPITAL KOTHAPET

2. Spectrum of conditions related to the development of the hip in infants and young children. It includes abnormal development of the acetabulum and proximal femur and mechanical instability of the hip joint.

3. Typical DDH which generally occurs in otherwise healthy infants. Teratologic hip dysplasia: occurs in association with various syndromes ( Ehlers-Danlos, Down syndrome, arthrogryposis) Neuromuscular hip dysplasia: occurs when there is weakness and/or spasticity in some or all of the hip muscle groups (in spina bifida or cerebral palsy).

4. Term Definition Dysplasia Abnormality of the shape of the hip joint (usually shallowness of the acetabulum, involving the superior and anterior margins). Sublaxatable / sublaxable The femoral head is reduced (within the acetabulum) at rest but can be partially dislocated or subluxated with examination maneuvers. This is a hip with mild instability or laxity . Dislocatable The femoral head is reduced at rest but can dislocate in other positions or with examination maneuvers. This is a hip with instability . Sublaxation The femoral head is partially outside of the acetabulum but remains in contact with it. Reducible The hip is dislocated at rest, but the femoral head can be positioned into the acetabulum with manipulation Dislocation Complete loss of contact between the femoral head and the acetabulum.

5. Epidemiology The incidence of DDH with dislocation is 1 to 2 per 1000 children . Mild hip instability is more common in newborns, with reported incidence as high as 40 percent It is increased in the Lapp and Native American populations (25 to 50 cases per 1000 births) and decreased in African and Asian populations

6. Both hips are involved in as many as 37 percent of patients . Among the unilateral cases, the left hip is affected more often than the right. may be related to the typical left occiput anterior fetal positioning, in which the left hip is forced into adduction against the mother’s sacrum

7. Risk factors Female sex: DDH is two to three times more common in female than in male infants - Transient increase in ligamentous laxity related to increased susceptibility of female infants to the maternal hormone relaxin Breech: Breech position during the third trimester is the greatest single risk factor for DDH. The absolute risk of DDH is as high as 12 percent in breech females and 3 percent in breech males The risk is higher in infants with frank breech than with footling breech presentation.

8. Successful external cephalic version was associated with decreased risk of DDH requiring treatment The increased risk of DDH is present regardless of the method of delivery. Family history: In a review of 589 patients with DDH, the risk of recurrence in subsequent children was 6 percent when there was one affected child, 12 percent when there was one affected parent, and 36 percent when there was an affected parent and an affected child

9. Swaddling: These practices limit hip mobility and position the hip in adduction and extension, which may play a role in the development of DDH Others : Associated with DDH but have not been proven to increase the risk These include torticollis, plagiocephaly, metatarsus adductus , clubfoot, being the firstborn infant, oligohydramnios, birthweight >4 kg, and multiple gestation pregnancies

10. Embryology and Pathogenesis

11. By the 11 week of gestation, the hip joint is fully formed. The femoral head grows at a faster rate than the acetabulum, so that by the end of gestation, the femoral head is less than 50 percent covered by the acetabular roof. During the final four weeks of gestation, the hip is vulnerable to mechanical forces, such as adduction , that direct the femoral head away from the central portion of the acetabulum. Conditions that limit fetal mobility , including breech positioning, accentuate these mechanical forces. This results in eccentric contact between the femoral head and the acetabulum.

12. Abnormal ossification of the acetabulum occurs and a shallow acetabulum develops With time, the intra-articular structures hypertrophy, including the labrum with a thickened ridge ( neolimbus ), ligamentum teres, and fibrofatty tissue (pulvinar). Contractures develop in the iliopsoas and hip adductors, and the inferior capsule is pulled into the empty acetabulum, further decreasing the potential for the femoral head to reduce into the acetabulum.

13. A false acetabulum may form where the femoral head contacts the lateral wall of the pelvis above the true acetabulum. The lack of contact between the femoral head and acetabulum inhibits further normal development of the hip joint.

14. Clinical features The spectrum of presentation ranges from instability on the newborn examination, to subtle limited abduction in the infant, to asymmetric gait in the toddler, to activity-related pain in the adolescent, to osteoarthritis in the adult. The most important aspects of the examination are hip instability in the young infant and range of motion in the older infant and child

15. Hip instability: Each hip should be examined individually for reducibility and instability. The infant should be on a stable surface in the supine position, with the hip flexed to 90° and in neutral rotation. The examination should occur when the infant is calm and not crying. The hips are best examined with all clothing and diapers removed from the lower extremities

16. ORTOLANI SIGN The thigh is grasped loosely with the examiner's index and middle finger along the greater trochanter and the thumb on the inner thigh. From an adducted position, the hip is gently abducted while lifting or pushing the trochanter anteriorly Extreme abduction should be avoided as it decreases the sensitivity of the Ortolani maneuver

17. ORTOLANI SIGN If the hip is dislocated, the Ortolani maneuver may reduce it and is accompanied by a palpable clunk.

18. BARLOW’S TEST The thigh is grasped loosely with the examiner's index and middle finger along the greater trochanter and the thumb on the inner thigh. The hip is gently adducted and, no downward pressure is applied, and the head is palpated to detect moving out of the back of the acetabulum. The examiner should not attempt to forcefully dislocate the femoral head.

19. If the hip is dislocatable , posterior movement and a palpable clunk may be detected as the femoral head exits the acetabulum. The combination of the Barlow and Ortolani maneuvers has a high specificity (approximately 98 to 99 percent) in the detection of hip instability.

20. Asymmetry: Helpful in unilateral DDH. Lack of asymmetry does not exclude DDH and may delay the diagnosis. (37% B/L)

21. Galeazzi/Allis/Perkins This is performed with the infant supine, hips flexed to 90°, knees flexed, and feet flat on a level surface and side by side, with the heels in apposition to the buttocks. In this position, the knees are normally at the same level. In unilateral dislocation, the head of the femur is displaced posteriorlyfunctionally shortening the thigh, and the ipsilateral knee will be lower than the other knee. A positive Galeazzi test is not specific for DDH. Other causes of leg-length discrepancy must be considered ( eg , hemihypertrophy, femoral hypoplasia, coxa vara ).

22. Asymmetry in the position or number of the inguinal, thigh, or gluteal skin folds may be a clue to the diagnosis of unilateral DDH. In the case of DDH,the increased folds are caused by "bunching" of the skin and muscle around a functionally shortened femur. Asymmetric skin folds are less helpful than other signs in predicting DDH. Asymmetric skin folds are sensitive but not specific for DDH, since skin fold asymmetry is present in approximately 24 percent of all infants

23. Range of motion In a child older than two to three months, limitation of abduction (<45°) is the most reliable sign of DDH. Normal range of motion in a supine infant with the pelvis stabilized is >75° for abduction and at least 30° past the midline for adduction Infants younger than two to three months may have normal adduction because they have not had enough time to develop an adduction contracture.

24. Klisic test A positive Klisic test is suggestive of DDH. Performed by placing the index finger on the anterior-superior iliac spine and the middle finger on the greater trochanter. An imaginary line between these points passes through or above the umbilicus in a child without DDH (negative). The line passes below the umbilicus if the hip is dislocated (positive Klisic test) because the greater trochanter is in a more superior position. The Klisic test is particularly helpful in bilateral dislocations when abduction is symmetrical and the Galeazzi sign is negative

25. Bilateral dislocation In infants younger than three months, the tests for instability may be useful in detecting bilateral DDH. As DDH progresses, dislocated hips become irreducible and instability is no longer detected. Findings related to symmetry (Galeazzi sign, thigh folds) are not helpful in bilateral dislocation

26. In children older than three months, the most important examination finding for bilateral dislocated hips is symmetric limited abduction (<45°). Other signs may include widening of the perineum, bilateral positive Klisic tests, and short thigh segments relative to the child's size

27. Trendelenburg test Normally, the pelvis stays level when a patient stands on one leg. When standing on the affected leg, the pelvis tilts downward toward the unaffected side because of gluteal muscle weakness on the affected side

28. Dysplasia without dislocation Usually has no clinical findings and is asymptomatic until adolescence or early adulthood. It is often found only through diligent screening of risk factors or incidentally when radiographs are obtained for other concerns or for assessment of activity-related hip pain in an adolescent or young adult.

29. Diagnostic imaging Ultrasonography Primary imaging technique for assessing the morphology and stability of the infant hip. It is an important adjunct to the clinical evaluation until four to six months of age. Helpful in confirming physical examination findings and evaluating infants with risk factors who have normal examination findings.

30. The alpha angle is measured from the lateral wall of the ilium and the bony roof line. The beta angle is the angle formed by the lateral wall of the ilium and the cartilaginous roof line. These angles are used to classify DDH according to the Graf system

31. Another important parameter is the percentage of the femoral epiphysis that is covered by the acetabular roof. For infants younger than four months of age, generally consider coverage of >50 percent to be normal. and the alpha angle measures greater than 60° Femoral head is less than 50% covered by the bony acetabulum and that the alpha angle measures less than 60°.

32. Radiographs Radiographs helpful in the evaluation of DDH after four to six months of age. Before that, radiographs have limited value because the femoral head and acetabulum are cartilaginous and unossified. After four to six months, when AP radiographs are obtained, the hips should be in the neutral position

33. Complete superolateral dislocation of the left femoral head (arrow). The left acetabulum is shallow (asterisk). Smaller size of the femoral epiphysis on the dislocated left side. The right hip is normal. The heart shape is a lead shield protecting the ovaries.

34. Radiographic findings consistent with DDH: Lateral and superior positioning of the ossified portion of the femoral head and neck Increased acetabular index Delayed appearance of the femoral ossific nucleus on the involved side or asymmetric sizes of the femoral ossific nuclei

35. Hilgenreiner and Perkins lines Hilgenreiner line is a horizontal line through the upper margin of the radiolucent triradiate cartilage. Perkins line is a vertical line drawn from the most lateral ossified margin of the roof of the acetabulum and perpendicular to Hilgenreiner line. In the normal hip, the medial end of the ossified upper femoral metaphysis lies medial to Perkins line and inferior to Hilgenreiner line. In the subluxated hip, it lies lateral to Perkins line. In the dislocated hip, it lies lateral to Perkins line and superior to Hilgenreiner line.

36. Shenton line Shenton line is drawn from the medial border of the femoral neck to the superior border of the obturator foramen. In the normal right hip, it is a continuous contour, whereas in the hip with DDH (the left hip), it is disrupted.

37. Acetabular Index Angle formed between Hilgenreiner line and a tangential line to the lateral ossific margin of the roof of the acetabulum. The acetabular index changes with axial and sagittal plane rotation of the pelvis and is helpful in measuring the development of the osseous roof of the acetabulum. In the newborn, the acetabular index must be over 40° to be significantly abnormal.

38. Both femoral heads are displaced laterally and superiorly. The acetabular index (AI) is also increased (>40°) bilaterally.

39. Other imaging modalities, such as arthrography, CT, and MRI are not useful in the diagnosis of DDH but may be used to evaluate postsurgical reduction Compared with CT, MRI exposes the patient to no radiation and provides information about vascularity of the femoral head. It is also helpful for evaluating long-term sequelae of partially treated or untreated DDH, such as labral tears and arthritis

40. Diagnosis Physical examination: Demonstrating hip instability , asymmetry (in unilateral cases), and/or limited abduction Imging : Used to make the diagnosis in infants with inconclusive examination findings. Also used to make the diagnosis in infants who have risk factors and normal examination

41. Ultrasonography generally is preferred for infants younger than four to six months of age and radiography for infants older than four to six months. Ultrasonographic measurements are used to classify DDH according to the Graf system. Radiographic findings of DDH include lateral and superior positioning of the ossified portion of the femoral head and neck, increased acetabular index, and delayed appearance of the femoral ossific nucleus on the involved side or asymmetric sizes of the femoral ossific nuclei

42. Approach to diagnosis and referral Positive Ortolani or positive Barlow Referral to an orthopedic surgeon Suboptimal or inconclusive examination Newborn – If the newborn examination is suboptimal (the infant is not relaxed enough for a reliable assessment of motion and stability) or inconclusive (no evidence of instability, but with joint clicks or thigh asymmetry) Re-examined at the next health supervision visit (usually at four weeks of age).

43. Four weeks Referral to an orthopedic surgeon for further evaluation and management. Alternative courses of action, depending upon the level of suspicion, include: Ultrasonography at six to eight weeks (adjusted for prematurity), at which point "minor" ultrasonographic abnormalities found in newborns should be resolved Continuing to follow clinically

44. Four weeks and older For infants four weeks and older with subtle or nonspecific findings, suggest imaging or referral. ultrasonography if the infant is younger than six months and radiographs if the infant is older than six months of age Normal examination and risk factors The risk of dislocation is greatly reduced if the newborn examination is normal. USG of hip at 6 weeks

45. Obtain imaging (by ultrasonography at four to six weeks of age) for infants with any of the following risk factors Male and female infants with breech positioning at ≥34 weeks gestation Family history of DDH (including hip replacement for dysplasia before age 40 years in a close relative) History of clinical instability on examination If ultrasonography is unavailable or a child with a risk factor presents at six months or older, screening may be done with a radiograph of the hips and pelvis

46. The hips of infants with risk factors for DDH who have normal examination and normal imaging studies at six weeks (ultrasonography) or four months (radiographs) should continue to be examined at subsequent health supervision visits until the child is walking independently. Normal clinical examination at six weeks of age does not definitively exclude DDH Normal ultrasonography at six weeks of age is not necessarily predictive of absence of dysplasia

47. Normal examination and no risk factors Should continue to be examined for signs of DDH at subsequent health supervision visits. Normal findings at age six to eight weeks do not definitively exclude DDH

48. Screening

49. AAOS: Recommends against universal ultrasound screening of infants for DDH Pediatric Orthopaedic Society of North America (POSNA ): recommends following the American Academy of Pediatrics clinical practice guideline with clinical assessment for DDH at birth and every well-child visit until the child is walking normally and selective imaging of infants with risk factors

50. Treatment Goal of treatment To obtain and maintain concentric reduction (alignment of the geometric centers of the femoral head and the acetabulum) of the hip. In the young child, concentric reduction provides an optimal environment for the development of the femoral head and acetabulum. In the older child, who has completed development of the hip joint, concentric reduction helps to prevent or postpone development of osteoarthritis of the hip Concentric reduction is the goal no matter when DDH is diagnosed. The therapies necessary to achieve concentric reduction vary depending upon the age at presentation or diagnosis, stability, and severity

51. 0 to 4 weeks The management of infants younger than four weeks of age depends upon the clinical findings and risk factors Laxity: Usually improves spontaneously It is important to avoid over-diagnosis and overtreatment of DDH in this age group. If mild instability/laxity is found in the newborn nursery, repeat examination after four weeks of age is suggested

52. Dislocation or instability: Prompt referral (within a few weeks) to an orthopedic surgeon is indicated if the hip is dislocated or dislocatable (at any age), or if laxity persists beyond four weeks of age Pavlik harness

53. 4 weeks to 6 months: Mild instability Re-examination and ultrasonography at six weeks of age. However, some orthopedic surgeons begin treatment with a Pavlik harness.

54. Dislocation or persistent instability These types of DDH are unlikely to resolve without treatment and may result in functional disability, pain, and accelerated osteoarthritis. Treatment with an abduction splint ( eg , Pavlik harness, von Rosen splint). The choice of abduction splint varies regionally. The Pavlik harness is the most thoroughly studied and most commonly used abduction splint worldwide. Frejka pillow is another type of abduction device used in the treatment of DDH, but it has been associated with an increased rate of avascular necrosis.

55. Pavlik harness The Pavlik harness is a dynamic splint that prevents hip extension and limits adduction (which can lead to dislocation), but permits flexion and abduction. This positioning promotes normal development of a dysplastic hip and stabilization of a subluxated hip and usually leads to gradual reduction of a dislocated hip, even if it is not reducible on physical examination

56. Indications: For infants younger than six months with hip dislocation or persistently dislocatable or subluxatable hips Contraindications: Muscle imbalance (spina bifida) Severe stiffness (arthrogryposis) Excessive laxity (Ehlers-Danlos syndrome) Age older than 10 months Family situation in which consistent and careful use cannot be guaranteed

57. Application and instructions The Pavlik harness is typically fit with hip flexion of 100° and adduction limited to within three fingerbreadths of the midline (the knees should be separated by six fingerbreadths when brought to the midline). Abduction is not forced but encouraged via gravity. Weekly or biweekly adjustments are necessary to maintain the ideal position. Caregivers are cautioned regarding hyperflexion and hyperabduction of the hips, which may cause femoral nerve palsy and osteonecrosis, respectively. Ultrasonography is used to monitor treatment.

58. Duration of treatment Two to three months usually necessary for patients who demonstrate improvement with the Pavlik harness. A combination of clinical examination demonstrating a stable hip and ultrasonography demonstrating improved acetabular development are used to determine when treatment can be discontinued Discontinued after three weeks if a dislocated hip has not reduced.

59. Rigid abduction orthosis After failure of reduction with a Pavlik harness, a rigid abduction orthosis ( ie , brace that holds the hip[s] in abduction, but unlike the Pavlik harness is not flexible may be used to gain reduction Reduction under anesthesia is usually required if reduction with a rigid abduction orthosis is unsuccessful

60. Effectiveness – In observational studies, Dislocatable or subluxatable hips improve in approximately 95 percent of cases For complete dislocation is approximately 85 percent (with success defined as achievement and maintenance of hip reduction). For children older than four weeks, the age at initiation of Pavlik harness treatment is an important predictor of outcome. Earlier treatment is associated with greater success Early failure of Pavlik harness treatment is more likely when there is low percentage coverage (<20 percent) of the femoral head, a high dislocation (one in which the femoral head has migrated superiorly), or irreducible dislocation on physical examination

61. Complications Complications of Pavlik harness therapy include Osteonecrosis of the femoral head, residual dysplasia, femoral nerve palsy, and skin breakdown. Other complications may include brachial plexus palsy, knee subluxation, inferior dislocation, and Pavlik disease (flattening of the posterior acetabulum caused by excessive hip abduction and flexion)

62. Dysplasia without dislocation Treatment with the Pavlik harness if isolated acetabular dysplasia (Graf type IIa or worse) persists beyond six weeks of age Monitor treatment with ultrasonography every four to six weeks until the ultrasonographic measurements become normal, at which point use of the Pavlik harness is weaned over six weeks. Follow-up radiographs are obtained at six months of age and regularly until skeletal maturity

63. AGE 6 TO 18 MONTHS OR FAILURE OF ABDUCTION SPLINT Closed or open reduction performed in the operating room under anesthesia In children older than six months, the rate of successful reduction with Pavlik harness treatment is less than 50 percent, and there is a higher risk of osteonecrosis (avascular necrosis) of the femoral head

64. Timing of reduction Soon after the diagnosis is made. The age of the child and development of the hip joint at the time of treatment affect outcome. The earlier the hip is reduced, the more likely the success of closed reduction; the older the patient, the more likely the need for open reduction and possible femoral and pelvic osteotomies Reduction before ossification of the capital femoral epiphysis was associated with decreased rate of subsequent reconstructive surgery ( eg , varus rotational osteotomy, pelvic osteotomy) compared with reduction after ossification

65. Closed reduction The goal is to place the femoral head into the acetabulum and to maintain it in this position with a spica cast. Closed reduction involves gentle manipulation of the hip to achieve reduction. Performed under general anesthesia using intraoperative arthrography and fluoroscopic imaging to guide positioning. Wide abduction should be avoided to decrease the risk of osteonecrosis .

66. It is important that reduction is achieved with gentle manipulation. Forced reduction and reduction requiring a high degree of abduction are likely to result in complications or poor outcomes ( eg , redislocation , osteonecrosis). If it is not possible to reduce the hip with gentle manipulation (with or without release of adductors), closed reduction is abandoned and open reduction is performed.

67. Spica cast is applied to maintain the position. After a successful closed reduction, the spica cast should hold the hips in 100° of flexion and 40 to 50° of abduction CT or MRI is usually obtained immediately postoperatively to confirm reduction. Specially formatted "spica MRI" facilitates a shorter time for image acquisition without need for sedation. Contrast enhancement may provide additional information about femoral epiphyseal perfusion

68. Casting is typically continued for three to four months after closed reduction. Cast changes and repeat hip arthrography may be performed at six-week intervals as clinically necessary. Complications of closed reduction include redislocation , osteonecrosis, and skin breakdown

69. Open reduction Typically performed after an unsuccessful attempt at closed reduction or primarily in patients who are older than 18 months The hip capsule is opened to remove the obstacles to reduction, including medial capsular constriction, inverted labrum , neolimbus , pulvinar, hypertrophied ligamentum teres and transverse acetabular ligament, and tight iliopsoas tendon Additional procedures, such as femoral or pelvic osteotomies and adductor tenotomy, may be required to increase hip stability.

70. After open reduction, a spica cast is placed with the hips held in approximately 30° of flexion and 30° of abduction to avoid postoperative flexion contractures. Post op imaging to confirm the position Casting typically is continued for six weeks to three months after open reduction. Cast changes may be performed at six-week intervals as clinically necessary. Generally remove the cast six weeks after open reduction and begin night-time abduction splinting with a rigid abduction orthosis, which is continued for six weeks. Complications of open reduction include redislocation , osteonecrosis, infection, scar, and stiffness

71. Dysplasia without dislocation Use a Part-time or full-time abduction orthosis, such as a rhino abduction brace or a spica cast. This allows improved positioning of the femoral head within the acetabulum to promote acetabular development during a time when there is good potential for acetabular remodeling

72. Treatment with a part-time or full-time abduction orthosis is reasonable up to the age of three or four years. If by that age there is still evidence of acetabular dysplasia, the orthopedic surgeon may recommend continued observation with serial radiographs every 6 to 12 months or proceed with pelvic osteotomy to correct dysplasia. The duration of observation of acetabular dysplasia and the age at which an osteotomy may be recommended varies from center to center.

73. Age ≥18 months: Dislocation The risks and benefits of reduction are weighed Possible risks of surgery are osteonecrosis and proximal femoral growth disturbance, residual dysplasia, and the need for additional surgeries Benefits of successful surgery include correction of leg length discrepancy and prevention or postponement of development of osteoarthritis of the hip Reduction of unilateral dislocation generally is undertaken until 9 or 10 years of age and reduction of bilateral dislocations until approximately 8 years of age. After these age limits, surgical outcomes are likely to be less satisfactory than the untreated natural history.

74. After ≥18 months of age, closed reduction of a dislocated hip is less likely to b successful, and open reduction is usually required. Concomitant procedures ( eg , adductor tenotomy, iliopsoas release, capsulorrhaphy , femoral shortening and derotational osteotomy, acetabular osteotomy) also are more likely to be necessary. Residual or late-presenting acetabular dysplasia Treatment usually involves acetabular osteotomy with or without femoral osteotomy

75. Long term follow up Children treated for hip dysplasia should have regular radiographs until they are skeletally mature to ensure that the hip is developing normally and to look for late complications or sequelae ( eg , recurrent or residual dysplasia, osteonecrosis, osteoarthritis). The frequency of long-term follow-up varies

76. Outcome Depends upon the severity of dysplasia, the age of diagnosis and treatment, and whether a concentrically reduced hip joint was obtained. The earlier the patient is treated, the greater the likelihood of a good outcome, highlighting the importance of early diagnosis

77. References UpToDate IAP STANDARD TREATMENT GUIDELINES 2022 - IGV