ANATOMIC HIP AND KNEE CONDITIONS

1. ANATOMIC HIP AND KNEE CONDITIONS DR. MOSI

2. OVERVIEW • DDH • Coxa vara • Genu valgum • Genu varus • Genu recarvatum

3. DEVELOPEMENTAL DYSPLASIA OF THE HIP Spectrum of disorders including : • Acetabular dysplasia • Instability (dislocation and subluxation) • Teratological malarticulation – dislocation in utero , irreducible at birth , pseudoacetabulum and associted with neuro muscular conditions eg arthrogyposis

4. Incidence • Left > right • Females > males at 7:1 • 20 % bilateral • At birth dislocation is 1:1000 and dysplasia 1:100

5. Aetiology and pathogenesis • Genetics • Generalized joint laxity – dominant • Shallow acetabular – polygenic • Hormonal factors • High levels of progesterone and relaxin in last days of pregnancy hence ligament laxity • Intrauterine malposition • complete breech, oligohydraminos,packaging deformities ( congenital muscular torticollis, metatarsus adductus, congenital knee dislocation • Postnatal factors

6. Initial instability leads to dysplasia • Normal acetabulum but lax capsule • Changes in the acetabulum and femoral head occur from the instabilty but some from primary acetabular and femoral head dysplasia • Dislocation is posterolateral then superolateral • Cartilagenous head of normal size but nucleus appears late • Shallow anteverted socket • Stretched capsule

7. Elongated and hypertrophied ligamentum teres • Superior limbus and capsule pushed into socket • On weightbearing above changes worsen • False socket is created

8. Presentation • Idelly diagonised at birth • Barlows test • Ortolanis test • Galeazzis test • limited abduction • clicking hip • asymetry in skin folds – thigh gluteal labial • trendelenburg gait , waddling gait • Ludolfs sign

9. BarlowsOrtolanis

10. Imaging • Radiographs useful at 4-6 months after head begins to ossify • Helgenreiners line • Shentons line • Perkins line • Acetabular index • Center edge angle of wiberg

11. Ce 20 -25. ai- 30 20 <20

12. Ultrasound • Dynamic ( Hacke) and static (graf) • Useful before head ossification • Alpha angle : lines along bony acetabulum and ilium ( >60) • Beta angle : line along labrum and ilium (<55) • Use in high risk group or in positive physical findings • Monitoring of treatment

14. arthrogram • Confirmation after closed reduction • Identification of possiblle blocks: • Inverted labrum • Inverted limbus • Hour glass appearance

15. CT Scan : study of choice • MRI : significant role

16. Management • Abduction splinting • Pavliks harness , Von rosens • < 6months • Contraindicated in teratological hip • Requires normal muscle function for successful outcome • Complications • Avn • Skin breakdown • Brachial plexus injury

18. Closed reduction and spica casting • 6 – 2yrs • Failure of pavlicks harness • Traction may be applied prior • Under anaesthesia or gradually over about three weeks • 60 flexion, 40 abduction, 20 internal rotation • At 6 weeks convert to splint that prevents adduction

19. obstacles to reduction • ligamentumteres, • the transverse acetabular ligament, • the constricted anteromedial joint capsule • , an inverted and hypertrophied labrum • degree of anteromedial hip capsular constriction • Shortened iliopsoas and adductors

20. Open reduction and femoral osteotomy • > 2YEARS or in failed closed reduction between 6 mnths and 2 years • Anatomic changes such as anteversion and coxa valga • Traction preop may help • Hip spica for three months the splinting

21. Open reduction and pelvic osteotomies • Older children • Severe dysplasia with marked acetabular changes • Reduced potential of acetabular remodeling

22. Intertrochanteric varus osteotomy

23. Femoral lengthening osteomy

24. Salter innominate osteotomy

25. Acetabuloplasty Dega, ganz, permbenton

26. Triple osteotomy

28. Complications • Avascular necrosis Seen in all treatment forms Escessive forceful abduction Late surgery dx. By late appearance of ossification center Broadening of femoral neck or fragmentation • Failed reduction and recurence

29. COXA VARA • Reduction in neck shaft angle <120 • 160 at birth • 125 by adulthood

30. Type • Developemental • Congenital • Dysplastic • Acquired

31. Location • Physis • Metaphysis • Subtrochanteric

32. Congenital • Associated with congenital short femur and proximal femoral deficiency • Unilateral • Subtrochanteric • Ass with retroversion of femur and out toeing • High propensity of progression

33. Developemental • Onset of ambulation, trendelenburg gait usually noted • Defective endochondral ossification posteromedialy (physeal defect) • Pathognomonic sign is a inferoposterior metaphyseal fragment

34. DYSPLASTIC • Underlying bone anomaly eg rickets, fibrous dysplaia • Usually bilateral

35. ACQUIRED • Commonly due to • Trauma • Infection • iatrogenic

36. PROGRESSION • Results in increasing limb length discrepancy and abductor weaknes • Clinical features • Painless limp – waddling or trendelenburgs gait • Limb length desripancy • Developemental :Hilgenreinerepiphyseal angle > 60 - all progress. 45 – 60 may or may not progress. < 45 often correct spontaneously • Dysplastic and acquired unpredictable • Traumatic may resolve due to remodelling

37. Imaging

38. Inverted y -sign

39. Management • Halting deformity progression – investigate and treat renal osteodystrophy , rickets etc • Correct proximal femoral anatomy : • Poximal valgus osteotomy • Trochanteric • Subtrochanteric • Greater trochanter epiphysodesis • Greater trochanter transfer

40. Pauwels Y-SHAPED OSTEOTOMY, Langenskiöld intertrochanteric osteotomy, BORDEN SUBTROCHANTERIC OSTEOTOMY

41. Femoral Anteversion • Averages 40 at birth but decreases to about 10 -15 in adults. • about 5 more in females • Idiopathic or associated with other hip disorders eg sufe ddh cp dcv • In toeing gait but this usually resolves

42. Cosmesis • Anterior knee pain due to patellar malalignment

43. Management • Observation • Rotational osteotomy • Rarely indicated ( most children have no functional deficits) • Child over 10 – 12 years with internal rotation of > 80 and external rotation of <10 • Intertrochanteric vs mid-diaphysis

44. GenuVarum and Valgus • Physiologic – usually <2 years and bilateral) • Pathologic – trauma , infection, rickets, dysplaisia of bone ,blounts disease, • >2years • Unilateral • Severe • Associated shortening • Obesity

45. 10m-15

46. Clinical features • Cosmesis • Patellofemoral instability/ maltracking • Altered gait - lateral thrust, circumduction • Early walkers – genu varum

47. ASSESMENT • Determine severity • Intermalleoar distance and intercondylar distance • Metadiaphyseal angle • Langenskiold classification of tibia vara • Site : • distal femur vs proximal tibia • Likelihood of progress • is the cause permanent egepiphyseal bar, achondroplasia, osteochondroma • BMI >22

48. Radiograph • Full length standing • Line should bisect knees