THE ROLE OF ARTHOGRAPHY GUIDED CLOSED REDUCTION

IN REDUCING THE INCIDENCE OF

AVN IN CDH

Published in J Ped. Orthop B 2005

INTRODUCTION

• CDH is common in S.A.• AVN is a know major complication of CDH

treatment that should be avoided.• Aim of the study:

– Compare incidence of AVN in C.R:• Without arthrography,

• With Arthrography guidance.

– Relation of type of limbus with incidence of AVN.

INTRODUCTION

AVN

Hip Arthrogram

INTRODUCTION

Medial adductor approach

INTRODUCTION

Arthrogram

INTRODUCTION

INTRODUCTION

“L-distance”

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INTRODUCTION

• Type of limbus (Leveuf):– Normal type I, sharp “Rose Thorn” sign.– Everted (subluxation pattern) type II– Inverted (dislocation pattern) type III

INTRODUCTION

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INTRODUCTION

Unconcentric Concentric

MATERIALS & METHODS

• A prospective study.

• Riyadh College of Medicine & KKUH.

• Jan 1992 – 1996.

• N = 85 patients.

• No prior treatment received.

• All closed reduction & hip spica.

MATERIALS & METHODS

• Two groups (closed reduction):– Group 1 arthrography guided.– Group 2 no arthrogram.

• Percutaneous adductor tenotomy done when needed.

• Follow up ≥ 5y.

MATERIALS & METHODS

• F/U:– 6 wks post C.R:

• If stable in extension broom-stick cast.• Otherwise another spica.

– Every 6 wks till hips fully stable:• Good acetabular cover,• Or till covered operatively.

• AVN Kalamchi & MacEwen.

MATERIALS & METHODS

• Chi square test (compare the incidence of AVN in both groups).

• Fisher’s exact test (compare between different types of limbus at time of reduction in relation to development of AVN).

MATERIALS & METHODSAccepted criteria for reduction

Group 1

• Concentric reduction (of the cartilaginous head).

• < 6 mm lateralization (irrespective of the limbus position).

MATERIALS & METHODSAccepted criteria for reduction

Group 2

• Clinical femoral head felt stable with C.R.

• XR ossific nucleus:• Present opposite triradiate c. & medial to Perkin’s line.

• Not present normal Von Rosen line & intact Shenton’s line.

RESULTS

• 85 patients.

• 124 hips.

• Female 59 (69%).

• Male 26 (31%).

• Age 3 -14m (average 7.3)

RESULTS

• Percutaneous adductor tenotomy done in:– 69 hips of 124 .– Group 1 = 40/48 (50.6%).– Group 2 = 29/37 (64.4%).

RESULTSComparison of patients in both groups

Group 1(CR with orthography)

Group 2(CR without orthography)

Total patients 48 37

Total hips 79 45

Mean age (m) 7.1 7.6

Female / Male 33 / 15 26 / 11

RESULTSOccurrence of AVN in both groups

Group 1(CR with orthography)

Group 2(CR without orthography)

AVN total 6 ( 7.6% ) 13 ( 28.9% )

type I 1 5

type II 2 1

type III 3 3

type IV 0 4

Mean age with AVN 8 8.9

RESULTSRelationship between classification of limbus & AVN in group I

Type of limbus

No. of

hipsF/M Lateralization

AVN I

AVN II

AVN III

AVN IV

AVN %

Normal 39 31/8 2 ± 0.5 1 0 0 0 2.6%

Everted 35 29/6 2.7 ± 1.3 0 2 0 0 5.7%

inverted 5 5/0 4.5 ± 0.5 1 0 2 0 60%

DISCUSSION

• Severin’s “Docking Theory”: “Soft tissue obstructing concentric reduction would

yield in time with continuous pressure from the head if the hip is maintained in an appropriate position”.

DISCUSSION

• Leveuf’s:

Docking without damage to the femoral head can occur if the obstacles to concentric reduction were minimal.

(e.g. everted limbus, minimal lateralization, & mild hour glass constriction).

Leveuf J. Primary congenital subluxation of the hip. J Bone Joint Surg [Am] 1947; 29-A : 149-162

Leveuf J. Results of open reduction of true congenital luxation of the hip. J Bone Joint Surg [Am] 1948; 30-A : 875-882

DISCUSSION

• Chuinard: Femoral head cannot be relied upon to

compress all soft tissue obstacles and seat itself normally without adverse effects on the femoral head especially in infants with a mostly cartilaginous femoral heads.

Chuinard EG. Femoral osteotomy in the treatment of congenital dysplasia of the hip. Orthop Clin North America 1972; 3 : 157-174

DISCUSSION

• Attempting C.R without arthrogram depends on:– Feeling good reduction,– Impression on position of the ossific nucleus:

• Not present !• If present it may be eccentric.

– Impression on amount of lateralization:• Other hip normal, can compare.• Other hip DDH !

DISCUSSION

Eccentric nucleus

DISCUSSION

• Still NO treatment for AVN.

• Its not justifiable to subject DDH patients to AVN.

Most of the time the outcome of no treatment is better than the outcome of treatment with severe form of

AVN.

CONCLUSION

C.R. without arthrography guidance is unsafe

due to high incidence of AVN.

CONCLUSION

Arthrography guided C.R.

less incidence of AVN.

( 7.6% c.f. 28.9% )

CONCLUSION

Inverted type of limbus higher incidence of AVN c.f. normal or everted limbus.

( 60% c.f. 4.1% )

RECOMMENDATION

Criteria of accepting

arthrography-guided closed reduction

1. Stable,

2. Concentric,

3. Lateralization ≤ 4 mm,

4. Non-inverted limbus.