The Epidemiology and Prognosis of Bilateral Legg-Calve-Perthes Disease

:A comparative study with unilateral LCPD

Sung-Taek Jung, Ju-Kwon Park, Nam-Young Cho, Sung-Man RoweSung-Taek Jung, Ju-Kwon Park, Nam-Young Cho, Sung-Man Rowe

Department of Orthopaedic Surgery Chonnam National University Hospital

Introduction Legg-Calve-Perthes disease

Most have unilateral involvement Prevalance of bilateral involvement : 8-24%

Salter et al, J Bone Joint Surg Am, 1984

Guille JT et al, J Pediatr Orthop, 2002

There was few study on bilateral LCPD Clinical course of bilateral disease has not been evaluated

exactly

Purpose

To know the epidemiologic difference of unilateral and

bilateral Legg-Calve-Perthes disease

To evaluate the outcome and prognosis of unilateral and

bilateral LCPD

MaterialsMaterials From 1973 to 2009

1099 patients were diagnosed as LCPD at our hospital 82 patients presented bilateral LCPD

Bilateral group : 82 patients, 69 male, 13 female Inclusion criteria

Waldenstrom stage was initial, fragmentation and reossification state

They were followed up periodically 69 patients were included

58 male, 11 female 69 patients presented unilateral LCPD

Unilateral group : 58 male, 11 female They were randomly selected

MethodsMethods Three groups

Group A : First affected bilateral LCPD Sex

58 male, 11 female Treatment method

Op 9 case, Conservative 60 case Group B : Second affected bilateral LCPD

Sex 58 male, 11 female

Treatment method Op 5 case, Conservative 64 case

Group C : Unilateral LCPD Sex

58 male, 11 female Treatment method

Op 18 case, Conservative 51 case

MethodsMethods Design

Retrospective study Plain radiograph review

Hip anteroposterior & frog leg view Reviewed by 2 orthopaedic surgeons

Statistic ANOVA test was used to evaluate differences in group

A, B and C

MethodsMethods Epidemiologic assessment

Distribution of sex & age Radiographic assessment

Initial Waldenstrom stage

Severity Catterall classification Lateral pillar classification

Outcome Radiologic

Stulberg classification 40 patients(bilateral) and 46 patients(unilateral) were evaluated

because of short follow up duration Clinical

Pain (VAS), limping, ROM limitation Limb shortening

Result - IResult - I Three group

Group A : First affected bilateral LCPD Onset age : 6.0 years (2.0-12.3) Follow up duration : 11.1 years (5.8-24.3)

Group B : Second affected bilateral LCPD Onset age : 6.8 years (2.4-13.1) Follow up duration : 11.1 years (5.8-24.3)

Group C : Unilateral LCPD Onset age : 6.1 years (2.1-11.6) Follow up duration : 11.9 years (6.3-24.5)

Result - II

58(84.1%)

11(15.9%)

58(84.1%)

11(15.9%)

0

10

20

30

40

50

60

Unilateral Bilateral

Male

Female

Distribution of Sex & Age

No statistically difference between these group

28(40.6%)

33(47.8%)

8(11.6%)

23(33.3%)

36(52.2%)

10(14.5%)12(17.4%)

51(73.9%)

6(8.7%)

0

10

20

30

40

50

60

1st(A) 2nd(B) Uni(C)

<5 years old

5-9 years old

>9 years old

Result - III

23(33.3%)

32(47.8%)

13(18.8%)

55(79.7%)

8(11.6%)

6(8.7%)

38(55.1%)

21(30.4%)

10(14.5%)

0

10

20

30

40

50

60

1st(A) 2nd(B) Uni(C)

InitialFragmentationReossification

Waldenstrom Classification – Initial

Group p-value

A & B

A & C

B & C

0.002

0.054

0.000

Significant statistically difference between group A & B, B & C No statistically difference between group A & C 2nd hip present more initial finding than other group

Result - IV

34(49.3%)

22(31.9%)

13(18.8%)

0

5

10

15

20

25

30

35

Metachronous Synchronous N.A.

Case

Waldenstrom Classification – Synchronous vs Metachronous

Synchronous and metachronous was classified According to Waldenstrom classification at first visit

Onset interval in bilateral LCPD Average interval was 7.4 months (4.2-12.4)

Result - V

6(8.7%)

15(21.7%)

30(43.5%)

18(26.1%)

20(29.0%)

33(47.8%)

13(18.8%)

3(4.3%)3(4.3%)

16(23.2%)

29(42.0%)

21(30.4%)

0

5

10

15

20

25

30

35

1st(A) 2nd(B) Uni(C)

IIIIIIIV

Catterall Classification - Severity

Group p-value

A & B

A & C

B & C

0.000

0.697

0.000

Significant statistically difference between group A & B, B & C No statistically difference between group A & C 2nd hip presented milder finding than other group

Result - VI

10(14.5%)

39(56.5%)

20(29.0%)

41(59.4%)

19(27.5%)

9(13.0%)7(10.1%)

50(72.5%)

12(17.4%)

0

5

10

15

20

25

30

35

40

45

50

1st(A) 2nd(B) Uni(C)

ABC

Lateral pillar Classification - Severity

Group p-value

A & B

A & C

B & C

0.000

0.781

0.000

Significant statistically difference between group A & B, B & C No statistically difference between group A & C Class C was few in 2nd affected hip

Result - VII

11(27.5%)

8(20%)9(22.5%)

9(22.5%)

3(7.5%)

22(55%)

5(12.5%)5(12.5%)5(12.5%)

3(7.5%)

5(10.9%)

18(39.1%)

9(19.6%)

13(28.3%)

1(2.2%)

0

5

10

15

20

25

1st(A=40) 2nd(B=40) Uni(C=46)

IIIIIIIVV

Stulberg Classification - Outcome

Group p-value

A & B

A & C

B & C

0.001

0.454

0.031

Significant statistically difference between group A & B, B & C No statistically difference between A & C Class I was much more in 2nd hip

Result - VIII

Limping 2nd hip presented less limping than other group

Pain 2nd hip presented less pain than other group

ROM limitation 2nd hip presented less ROM limitation than other

group

Result - IX

38(55.1%)

6(8.7%)

12(17.4%)13(18.8%)

48(69.6%)

3(4.3%)

11(15.9%)

7(10.1%)

29(42.0%)

6(8.7%)

20(29.0%)

14(20.3%)

0

5

10

15

20

25

30

35

40

45

50

1st(A) 2nd(B) Uni(C)

0mm2-9mm

10-19mm

> 20mm

Limb shortening

Group p-value

A & B

A & C

B & C

0.220

0.354

0.007

Statistically difference between group B & C 2nd hip presented less limb shortening

DiscussionDiscussion Prevalance of bilateral involvement

In our study

1099 patients were diagnosed by LCPD from 1973 to 2009

Among them bilateral LCPD : 82 patient (7.5%)

Author Journal Published year

Total patient

Bilateral(%)

Katz

Kemp HS et al

Wynne-davies R et al

Harrison MHM et al

Salter et al

Guille JT et al

J Mt Sinai Hosp NY

Br J Radiol

J Bone Joint Surg Br

J Bone Joint Surg Br

J Bone Joint Surg Am

J Pediatr Orthop

1965

1973

1978

1980

1984

2002

209

220

310

222

936

637

9.0

10.0

11.3

10.4

23.9

13.0

DiscussionDiscussion

Onset interval between 1st and 2nd hip Bilateral involvement usually developed within two years

of unilateral onset

Sakai R et al, J Jpn Paed Orthop Assoc, 1993

In our study, average interval to bilateral involvement

was 7.4 months (4.2-12.4) It wound be due to follow up interval

Our follow up interval was shorter than Sakai R

et al

DiscussionDiscussion Severity & Outcome

More severe course than unilateral one of Ippolito Higher percentage of severe form

Van den Bogaert G et al, J Pediatr Orthop B, 1999 Ippolito E et al, J Bone Joint Surg Br, 1987

Lateral pillar A hips: statistically more in the 2nd side Milder in patients with bilateral involvement

Treatment of the first side Protective effect on the second side unclear

Guille JT et al, J Pediatr Orthopt Br, 2002

In our study, second affected hip shows better results in outcome and prognosis

ConclusionConclusion

Prevalance of bilateral LCPD was 7.5% in our study Prevalance of bilateral LCPD was 7.5% in our study First affected hip First affected hip

Similar outcome and prognosis of unilateral Second affected hip Second affected hip

Stage : Present more initial stage by Waldenstrom Severity : Present milder finding by Catterall & Lateral

pillar Outcome : Present better state by Stulberg Limb shortening : Present less shortening

Thank you for your kind attention