Developmental Dysplasia of the Hip

1. Developmental Dysplasia of the Hip Dr. Nasser ALTurki Teaching assistant @sau . Orthopedics resident @RMH.

2. Overview • Introduction • Normal Development of the Hip • Etiology and Pathoanatomy • Epidemiology and Diagnosis • Treatment • Complications

3. Introduction • Developmental Dysplasia of the Hip • DDH - preferred term • Teratogenic hips • Subluxation • Dislocation-usually posterosuperior (reducible vs irreducible) • Dysplasia

4. Summary • Risk Factors • 1/1,000 born with dislocated hip • 10/10,000 born with subluxation or dysplasia • 80% Female • First born children • Family history (6% one affected child, 12% one affected parent, 36% one child + one parent) • Oligohydramnios • Breech (sustained hamstring forces) • Native Americans (swaddling cultures) • Left 60% (left occiput ant), Right 20%, both 20% • Torticollis or LE deformity

5. Normal Development • Embryonic • 7th week - acetabulum and hip formed from same mesenchymal cells • 11th week - complete separation between the two • Prox fem ossific nucleus - 4-7 months

6. Normal Hip • Tight fit of head in acetabulum • Transection of capsule • Still difficult to dislocate • Surface tension

7. Pathoanatomy • Ranges from mild dysplasia --> frank dislocation • Bony changes • Shallow acetabulum • Typically on acetabular side • Femoral anteversion

8. Pathoanatomy • Soft tissue changes • Usually secondary to prolonged subluxation or dislocation • Intraarticular • Labrum • Inverted + adherent to capsule (closed reduction with inverted labrum assoc with increased Avascular Necrosis) • Ligamentum teres • Hypertrophied + lengthened • Pulvinar • Fibrofatty tissue migrating into acetabulum

9. Pathoanatomy • Soft Tissue (Intraarticular) • Transverse acetabular ligament • Contracted • Limbus • Fibrous tissue formed from capsular tissue interposed between everted labrum and acetabular rim • Extraarticular • Tight adductors (adductor longus) • Iliopsoas

10. Tough Reductions… • Obstacles to reduction • Extraarticular • Tight iliopsoas and adductors • Intraarticular • Labrum • Ligamentum teres • Transverse acetabular ligament • Pulvinar • Redundant capsule (hourglass) • +/- limbus

11. Etiology and Epidemiology • Multifactorial • Genetics and Syndromes • Ehler’s Danlos • Arthrogryposis • Larsen’s syndrome • Intrauterine environmental factors • Teratogens • Positioning (oligohydramnios) • Neurologic Disorders • Spina Bifida

12. Diagnosis • Newborn screening • Ortolani’s and Barlow’s maneuvers with a thorough history and physical • Warm, quiet environment with removal of diaper • Head to toe exam to detect any associated conditons (Torticollis, Ligamentous Laxity etc.) • Baseline Neuro and Spine Exam

13. Diagnosis • Key physical findings • Asymmetry • Limb length- Galeazzi • Abduction ROM • Skin folds • Limp • Waddilng gait / hyperlordosis - bilateral involvement

14. Ortolani’s Maneuver * After 3 months of age tests become negative

15. Barlow’s Maneuver

16. Diagnosis • Some cases still missed • At risk groups should be further screened • AAP • Recs further imaging (e.g. US) if exam is “inconclusive” AND • First degree relative + female • Breech • Positive provocative maneuver (Ortolani or Barlow) • Referral to Orthopaedist

17. Imaging • X-rays • Femoral head ossification center • 4 -7 months • Ultrasound • Operator dependent • CT • MRI • Arthrograms • Open vs closed reduction

18. Imaging • Radiographs

19. Imaging • Radiographs

20. Imaging • Radiographs

21. Imaging • Radiographs

22. Imaging • Acetabular Index

23. Imaging • Acetabular Index

24. Imaging • Acetabular Index < 30 wnl

25. Imaging

26. Imaging

27. Imaging

28. Imaging

29. Radiographs Summary • Femoral head appears 4 - 7 months • Shenton’s line • Perkin’s and Hilgenreiner’s lines • Inferomedial quadrant • Center Edge Angle (< 20 abnormal) • Acetabular index • Normal < 30 (Weintroub et al) • Tear drop* • Abnormal widening in DDH *may be only sign in mild subluxation

30. Imaging • Ultrasound • Introduced in 1978 for eval of DDH • Operator dependent • Useful in confirming subluxation, identifying dysplasia of cartilaginous acetabulum, documenting reducibility • Prox Femoral Ossification Center interferes • Requires a window in spica cast (avoid)

31. Ultrasound Femoral head Abductors Ilium

32. Ultrasound Femoral head Abductors Ilium

33. Ultrasound Femoral head Abductors Ilium

34. Ultrasound Femoral head Abductors Ilium

35. Ultrasound Graf’s alpha angle

36. Ultrasound Graf’s alpha angle >60 = normal *line w/ ilium bisects head 50/50

37. Natural History • Newborn Variable • > 6 months more aggressive tx required due to more extensive pathology and decreased potential for acetabular remodeling • Abnormal Gait, Decreased Abduction and Strength, Increased DJD • Unilateral worse than Bilateral • Subluxation worse than Dysplasia

38. Treatment Options • Age of patient at presentation • Family factors • Reducibility of hip • Stability after reduction • Amount of acetabular dysplasia

40. Birth to Six Months • Triple-diaper technique • Prevents hip adduction • “Success” no different in some untreated hips • Pavilk harness (1944) • Experienced staff* • Very successful • Allows free movement within confines of restraints *posterior straps for preventing add. NOT producing abd.

41. Birth to Six Months • Pavlik harness • Indications • Fully reducible hip* • Child not attempting to stand • Family • Close regular follow-up (every 1-2 weeks) • For imaging and adjustments • Duration • Childs age at hip stability + 3 months

42. Pavlik Harness • Failures • Poor parent compliance • Improper use by the physician • Inadequate initial reduction • Failure to recognize persistent dislocation • Viere et al 1990 • Bilateral dislocation • Absent Ortolani’s sign • > 7weeks of age

43. Pavlik Harness • Complications • Avascular necrosis • Forced hip abduction • Safe zone (abd/adduction and flexion/extension) • Femoral nerve palsy • Hyperflexion *Be aware of Pavlik Harness Disease *Follow until skeletal maturity

44. Birth - Six months • Closed reduction + Spica • Failure after 3 weeks of Pavlik trial

45. Birth - Six months • Closed reduction • General anesthesia • Arthrogram • Safe zone - avoid AVN • +/- adductor tenotomy • Open reduction if concentric reduction not possible • Usually teratogenic hips in this age group

46. Open Reduction • Medial approach • Pectineus / adductor longus + brevis • Cannot address simeoultaneous bony work • Antero -lateral • Smith-peterson • Sartorius / Tensor Fascia lata

47. Open Reduction

48. 6 months - 4 years • Present a more difficult problem • Prolonged dislocation • Contracted soft tissues • 6 - 18 months • Closed reduction +/- adductor tenotomy • Spica in human position of 100 degrees of flexion and about 55 degrees abduction (3 months) • Abduction Orthosis 4 wks full time/4 wks nighttime • Open reduction (if closed fails) • Capsulorraphy • CT scan • Spica for 6 wks followed by PT

49. 6 months - 4 years • 18 months - 4 years • Closed reduction • Reducibile - check arthrogram and medial dye pool • Irreducible - Open reduction • Open redcution • Tight - femoral shortening • Stable - +/- pelvic osteotomy