1. Surgical Treatment Of Habitual Dislocation Of The Patella In Young Children: A 13 Year Follow-up Retrospective Study
Good morning. Today I will present the results of a long term follow-up study about a surgical technique aimed at treating habitual patellar dislocation in the young child.
Benoit Benoit, MD
Yves Laflamme, MD
Benoit Morin, MD
Guy Grimard, MD
Dominique Rouleau, MD

2. Habitual Patellar Dislocation = Severe Functional Disability
Habitual patellar dislocation in the young child always mean severe functional disability.

3. Habitual Patellar Dislocation
Dislocation occurs with activities of daily living
Sporting activities are almost impossible
…bescause dislocation occurs with ADL. Of course, getting involved in sporting activities is impossible.

4. Factors* Of Patellar Instability (Six)
According to Insall, there are 6 factors of patellar instability.
*Insall and Salvati, 2001

5. Factors of patellar instability
1) Patella alta
First, patella alta. A L T

6. Radiologic Patellar Height Assessment In The Immature Patient
Koshino-Sugimoto
Caton-Deschamps
Of these, patella alta is probably the most important one. In the young child, the Kushino-Sugimoto or the Caton-Deschamps method are the most appropriate to determine patellar height.

7. PT/FT = 1 Koshino-Sugimoto F F P P T T
Here is how to measure patellar height with the Koshino-Sugimoto ratio. First, you draw the longitudinal axis of the patella. Then you draw a line overlying femoral and tibial physis. Finally, you join the middle of these lines and measure them. PT on FT is the ratio. T T
Koshino-Sugimoto

8. AT/PA: 0.6-1.3 Caton-Deschamps P P A A T T
Caton-Deschamps method is more simple. You draw a line over the long axis of patella’s articular surface. Then you join the inferior part of it with the anterior aspect of the tibia’s surface. AT on PA is the ratio.
Caton-Deschamps

9. Factors of patellar instability
2) Hypoplastic Femoral Sulcus
160°
Second, Hypoplastic femoral sulcus.

10. > 150° = Trochlear dysplasia
N = 138°
> 150° = Trochlear dysplasia

11. Factors of patellar instability
3) Patellar Dysplasia
Third, patellar dysplasia.
Wiberg Classification

12. Factors of patellar instability
4) Muscle Imbalance
(VMO dysplasia)
Fourth, VMO dysplasia.

13. Factors of patellar instability
5) Increased Q angle
Fifth, Increased Q-angle.

14. Factors of patellar instability
6) Lower Limb Malalignment
And sixth, Lower limb malalignment

15. Treatment options?
What are the treatment options for a 9 yo child with this biomechanical problem?

16. No study addresses specifically habitual patellar dislocation in the young child
First of all, no litterature address specifically habitual patellar dislocation in the young child.

17. Treatment Options Conservative Surgical Physical therapy Knee bracing
In the older population, litterature suggests to start with conservative treatment for 6 months. If it fails, we should switch to surgery.

18. Does knee bracing prevent habitual patellar dislocation ?
But does knee bracing really prevent habitual patellar dislocation?

19. Does physical therapy prevent habitual patellar dislocation ?
And what about quad strenghtening?

20. +

21. + 40% Recurrence rate: Garth, Am J Sports Med, 1996
According to one article, reccurence rate is 40% for recurrent patellar dislocation. Of course it would be even higher for habitual dislocation.
Garth, Am J Sports Med, 1996

22. Surgical treatment

23. Literature
“Patella alta must absolutely be treated to obtain a satisfactory result”
Many authors, in the past, have recognized that patella alta must be addressed to treat patellar dislocation successfully. A L T A L T
Caton, J. Revue Chir. Ortho., 1990

24. Literature A L T
“Most common technical error in distal realignment is failure to correct patellar height”
Insall sais tha the Most common technical error in distal realignment is failure to correct patellar height”
Insall J., JBJS, 1976
Scuderi G. R., OCNA, 1992

25. Excessive medialization Posterior recessing
Distal
realignment
Excessive medialization
Posterior recessing
Late
osteoarthritis
Insall, JBJS, 1976

26. Surgical Options In The Patient With Open Physis
Roux-Golthwait
Galeazzi
Roux-Goldwaith and Galeazzi described the two techniques used in the growing child.

27. Roux-Goldthwait
The Roux-Goldthwait procedure splits the patellar tendon. The
lateral half is transferred medially, under its medial counterpart.

28. Galeazzi The Galeazzi procedure is a tenodesis of the semitendinosus.
transfers the semitendinosus to the
inferior pole of the patella. From there, it courses through a drill hole placed
obliquely through the patella, exiting the superior lateral aspect. The tendon is
then sutured to the soft tissues. This provides a medial tether and effectively
alters the net vector of the patellar tendon toward the medial side. Typically, the
vastus medialis is advanced approximately one-third the width of the patella.

29. Roux-Goldthwait Galeazzi P A T E L VS
But none of these techniques treat patella alta.

30. P A T E L
Roux-Goldthwait
Galeazzi

31. Bony procedures not appropriate
Elmslie-Trillat
And as you can figure, bony procedures on tibial tubercle are not appropriate in the immature child…
A, B: The Elmslie-Trillat technique shifts the tibial tubercle
medially. The tubercle stays in the same plane. C: The Fulkerson modification
involves an oblique cut that results in anterior translation as the tubercle is
moved medially. This reduces the patellofemoral contact forces while shifting the
pull of the patella medially. D: The Maquet procedure moves the tibial tubercle
anteriorly by inserting a block of bone. This diminishes the patellofemoral contact
forces but does not medialize the pull of the patellar tendo
Fulkerson

32. Tibial tubercule transfer on the knee with open physis
Genu recurvatum
…because they will lead to genu recurvatum by closing the the anterior part of the tibial plateau’s physis

33. In summary, the soft tissue procedures that are described to treat recurrent patellar dislocation in the patient with open physis are:

37. Long term follow-up (13.8 years)
Goal of our study
Clinical evaluation of a new procedure
to correct patella alta in children
with patellar instability
Long term follow-up (13.8 years)
The goal of Our study is the Clinical evaluation of a procedure to correct patella alta in children with patellar instability. We have a mean of 13.8 years of follow-up.

38. Materials and methods
Retrospective study

39. Materials and methods Retrospective study
12 consecutive knees treated surgically in young children from 1988 to 1994

40. Materials and methods Retrospective study
12 knees in young children treated surgically
Follow-up: years (mean 13.8 years)

41. Materials and methods Retrospective study
12 knees in young children treated surgically
Follow-up: years (mean 13.8 years)
Mean age at surgery: 10 years (6-14 years)

42. Materials and methods Retrospective study
12 knees in young children treated surgically
Follow-up: years (mean 13.8 years)
Mean age at surgery: 10 years (6-14 years)
Mean age at last follow-up: 25 years

43. Materials and methods Inclusion criterias
Habitual patellar dislocation
Functional limitations in activities of daily living
Symptoms of more than 1 year duration
Inclusion criterias were:

44. Failure of conservative treatment (bracing and physical therapy)
Growth plates opened at time of surgery

45. Materials and methods Preoperative clinical evaluation
High-riding patella
VMO dysplasia
Normal Q-angle
Positive apprehension test
Lateral patellar laxity IV/IV
At preop clinical evaluation, all patients presented:

46. Radiographic measures
Sulcus angle
Patellar height
…were measured at each visit

47. Surgical technique Proximal realignment: Distal realignment: NEW!
Lateral release
VMO advancement
Distal realignment:
Complete patellar tendon lowering
Hughston technique
Our surgical technique involved a formal proximal realignment as described by Hughston with a lateral release and a VMO advancement and reefing. The innovation in our technique involved a complete patellar tendon lowering.
NEW!

48. Patellar tendon dissection
Tibial tubercule
Patellor tendon exposed. Periosteum is removed distal to patellar tendon insertion to form the receiving bed. Here, patella has to be lowered by 2.5 cm as templated preop.
Templated advancement: 2.5 cm
Patellar tendon

49. Patellar tendon elevation
Tibial tubercle
Patellar tendon is elevated off tibial tubercule with a scalpel

50. Tendon preparation Receiving bed Transosseous sutures
The receiving bed on tibial metaphysis is prepared. Criss-cross sutures exit the tendon distally and will be anchored with transosseous stitches…

51. Distal tendon transfer
…as shown on this picture.

52. Tendon attached
Finally, patellar tendon new insertion is secured with multiple peripheral stitches.

53. Results

54. Mean patellar tendon lowering: 1.6 cm
Mean surgical patellar tendon lowering according to preoperative templating was 1.6 cm
(1 cm to 2.5 cm)

55. Results Last follow-up Instability: 0/12 Pain: 1/12
at last follow-up no one redislocated and patellofemoral pain was slight in one patient

56. Results Last follow-up Lateral glide test Apprehension test
Normal in 11/12

57. Results Lysholm knee score at last follow-up: Mean: 98/100
The most common complaint was minimal discomfort with squating

58. Recreational activities
Results
Recreational activities
Preop
Last f-up (13.8 y)
Limited
12/12
1/12
Preop all patients were at least limited in recreational activities. Postop, one is still limited

59. Results Sulcus Angle Preop 6 m 3.8 y 13.8 y Mean 160° 157° 147°
Interesingly, preop mean sulcus angle was 160°, and 13 years later, it went down to 147°.

60. Mean Patellar Height (Caton-Deschamps)
Results
Patellar Height
Preop
6 m
3.8 y
13.8 y
Mean Patellar Height (Caton-Deschamps) N:
1.53
0.96
0.97
1.11
All patellas were high before surgery. At follw-up, mean patellar height is in the normal range

61. Early postoperative complications (3)
1 redislocation (undercorrection)
Early reoperation
Now stable
1 wound abcess
Surgical drainage, Antibiotics
Healed
1 peroneal nerve neurapraxia
Recovered completely
Cast compression?

62. Late postoperative complications
Two patella bajas (Caton ratio) in children operated at 6 and 7 years old

63. Discussion

64. Discussion Risks of osteoarthritis minimized by:
no unnecessary medialization
no posterior recessing
high rate of patellofemoral stability
Our distal patellar tendon advancement involves: 1+2 and restores patellofemoral stability

65. Discussion Anatomic repositioning of the patella
eliminates delay of patellar engagement
maximizes buttressing effect of the lateral condyle, and…
By this technique,

66. …seems to remodel the shallow throchlea in the immature patient

67. Conclusion Realistic goals were achieved: Functional knee stability
Return to active life

68. Conclusion
Addressing patellar height is paramount in the immature patient

69. Conclusion Patella baja occurred in two patients
No clinical or radiological consequence
Consequences in the futur??

70. Conclusion
Trochlear remodeling occurs secondary to distal tendon transfer in the immature patient
But the most interesting,

71. Thank you

72. Who is right?
Caton normal
Insall: Patella baja

73. Lateral retinacular release alone in reccurent patellar dislocation
21% redislocation rate (7/33 knees)¹
35% redislocation rate (7/20 knees)²
Dandy and Desai, JBJS Br, 1989
Aglietti et al, J Orthop, 1994

74. Radiographic Evaluation
Lateral 45°
Lateral 90°
Merchant view
Preoperative
Postoperative
Intermediate follow-up (mean 3.8 years)
Latest follow-up (mean 13.8 years)
These four xrays were done:
Preoperative
Postoperative
Intermediate follow-up (mean 3.8 years)
Latest follow-up (mean 13.8 years)

75. Results Patellar Height Preop 6 m 3.8 y 13.8 y 1.53 0.96 0.97 1.11
Mean Patellar Height (Caton-Deschamps) N:
1.53
0.96
0.97
1.11
Mean Patellar Height (Koshino-Sugimoto)
1.28
1.06
All patellas were high before surgery. At follw-up, mean patellar height is in the normal range

76. Conclusion
The described surgical procedure is a comprehensive and effective approach to habitual patellar dislocation in young children

77. Lateral release
Extended lateral release

78. Patient preparation
First, patient prep

79. Physical exam
(under anesthesia)
PE under GE

80. Lateral release
Extended lateral release

81. VMO advancement

82. Wound closed
Wound is closed in layers.