Quantification of ant laxity of the knee stress Xr · 2017. 1. 12. · and 487 ACL deficient knees...

Stress-radiography of the kneeAnterior and posterior translation

at 20° of flexion in 563 normal knees

and 487 ACL deficient knees

StressStress--radiographyradiography of the of the kneekneeAnteriorAnterior andand posteriorposterior translation translation

atat 2020°° of flexion of flexion in 563 normal in 563 normal kneesknees

andand 487 ACL 487 ACL deficientdeficient kneesknees

AimsAims of the of the studystudy

•• The The measurementsmeasurements of of anterioranterior andand posteriorposterior laxitylaxity–– in normal in normal kneesknees–– andand in ACL in ACL deficientdeficient kneesknees

•• DiagnosisDiagnosis valuevalue

•• GradingGrading the the kneeknee play in play in orderorder to to choosechoose adaptatedadaptatedsurgerysurgery

Flexion : 90°• Nyga : 1970• Kennedy, Fowler : 1971• Lerat : 1971• Jacobsen : 1976

AnteriorAnterior stressstress--radiographyradiography

TORG introduced the "LACHMAN test"

in 1976

Test practised since 1963 byTRILLAT in Lyon-France

AnteriorAnterior stressstress--radiographyradiography

AnteriorAnterior stressstress--radiographyradiography

20° of flexion• Lerat (manually) : 1979• Lerat (apparatus) : 1982• Stäubli, Jakob : 1982• Hooper : 1986• Iversen : 1988

apparatus

l

apparatus

Manualy

AnteriorAnterior andand posteriorposterior stressstress--radiographyradiography

The same apparatus is used for both anterior and posterior tests

•• 2020°° of flexionof flexion•• FixedFixed loadload (9 kg)(9 kg)•• Free translationFree translation•• Free rotationFree rotation•• ComfortableComfortable for the for the

patientspatients

AnteriorAnterior translation of the tibiatranslation of the tibia

•• PosteriorPosterior tibial cortextibial cortexas as referencereference lineline

•• ParallelsParallels tangent to the tangent to the posteriorposterior aspect of the aspect of the condylescondyles

•• Distance Distance betweenbetween thesethesetangent tangent lineslines andand the the tibial tibial compartmentscompartments

ATMC: ATMC: AnteriorAnterior Translation of Translation of MedialMedial CompartmentCompartment

ATLC : ATLC : AnteriorAnterior Translation of Translation of LateralLateral CompartmentCompartment

LandmarksLandmarks

Lateral condyle : anterior notch and posterior angle

ATMC

ATLC

ATMCATMC andand ATLCATLC

AnteriorAnterior radiologicalradiological drawerdrawer

PTMCPTMC = = PosteriorPosterior Translation of Translation of MedialMedial CompartmentCompartment

PTLC = PTLC = PosteriorPosterior Translation of Translation of LateralLateral CompartmentCompartment

PosteriorPosterior translation of the tibiatranslation of the tibia

• 1050 knees measured• 487 ACL insufficient knees• 487 contra-lateral normal knees• 76 normal subjects

• age : 27.5 ± 9 years (16-50)

• 70.5 % males, 29.5 % females

• no previous surgery• no meniscus bucket-handle

MaterielMateriel

• 2100 X-ray films• 4200 measurements

• One observer (JL L)

methodsmethods

Interobserver intraclass correlation3 observers

50 patients measured(ruptured ACL - normal knee)

Intraobserver intraclass correlation1 observer measured 50 patients twice

MethodsMethods

Normal Deficient ACL ATMC 0.91 (0.85 - 0.95) 0.95 (0.90 - 0.98)

0.97 (0.95 - 0.98) 0.98 (0.94 - 0.98)

ATLC 0.92 (0.85 - 0.95) 0.92 (0.85 - 0.95)

0.93 (0.89 - 0.96) 0.95 (0.92 - 0.97)

Intra and interobserver intraclass correlationfor ATMC and ATLC

All values include 95 % confidence intervals

Right-left difference38 normal subjects

Ant Transl Medial Comp : 0.5 ± 0.4 mm

Ant Transl Lateral Comp : 1.2 ± 0.4 mm

Post Transl Medial Comp : 1.1 ± 0.7 mm

Post Transl Lateral Comp : 1.5 ± 1.2 mm

RESULTSRESULTS

ATMC = 10.4 ± 4.3

ATLC = 18.5 ± 5.1

PTMC = 2.7 ± 2.9

PTLC = 1.1 ± 4.1

ATMC = 2.1 ± 2.6

ATLC = 10.5 ± 3.5

PTMC = 2.1 ± 2.9

PTLC = 1.7 ± 4.1

563 normal knees 478 ACL deficient knees

No difference between males and females

RESULTSRESULTS

• No difference for posterior translation (ACL ruptured or not )

• Posterior position is different from the radiological "zero position"

• It is the "starting position" for clinical tests and for arthrometric measurements

RESULTSRESULTS

PTMC = 2.1 ± 2.9

PTLC = 1.7 ± 4.1

•• specificityspecificity = 90 %= 90 %•• sensitivitysensitivity = 87 %= 87 %•• predictpredict positposit. val = 89 %. val = 89 %•• predictpredict negatnegat. val = 88 %. val = 88 %

•• 87%87%•• 79 %79 %•• 85 %85 %•• 82 %82 %

ATMCATMC ATLCATLC

Cut point : 6 mm Cut point : 11.5 mm

DiagnosisDiagnosis of ACL rupture of ACL rupture The ATMC The ATMC isis the the mostmost reliablereliable

.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1.0

.0

.1

.2

.3

.4

.5

.6

.7

.8

.9

1.0

1-specificity

Sens

itivi

ty

Medial

Compartment

PTMC +ATMC

4.2 ± 2.7 mm

PhysiologicalPhysiological antant--postpost laxitylaxity

LateralCompartiment

PTLC +ATLC

12.2 ± 4.5 mm

Medial

Compartment

PTMC +ATMC

12.1 ± 4.5 mm

PathologicalPathological antant--postpost laxitylaxity

LateralCompartiment

PTLC +ATLC

19.4 ± 5.5 mm

Considering differential laxity

PathologicalPathological ATMCATMC andand ATLC ATLC Normal Normal contralateralcontralateral kneeknee

ACL ACL deficientdeficient kneesknees : : differentialdifferential antant. translation. translation

ATLC7.5 ± 4.6 mm

ATMC

8.1 ± 4.2 mm

0

10

20

30

40

50

60

70

80

-5 0 5 10 15 20 25

Differential ATLC

0

10

20

30

40

50

60

70

80

-5 0 5 10 15 20

Differential ATMC

• Translation of the lateral sidecan be predominent

internal tibial rotation

AnteriorAnterior laxitieslaxities classificationclassification

• Translation of the medial sidecan be predominent

external tibial rotation

< 5mm

5-8mm

8-11mm

>11mm

05

1015202530

< 5mm

5-8mm

8-11mm

>11mm

AnteriorAnterior laxitieslaxities classificationclassification

ATMCATMC

Casesnumber

%

AnteriorAnterior laxitieslaxities : grade 1: grade 1

5

8

11

Diff. Laxity mm

zero position line

15

AnteriorAnterior laxitieslaxities : grade 1: grade 1

1285

8

11

Diff. Laxity

zero position line

15ATMC

knees

AnteriorAnterior laxitieslaxities : grade 1: grade 1

128 595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

AnteriorAnterior laxitieslaxities : grade 1: grade 1

128

36

595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

AnteriorAnterior laxitieslaxities : grade 1: grade 1

128

36

22

595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

AnteriorAnterior laxitieslaxities : grade 1: grade 1

128

36

22

11

595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

116 25

25

18

485

8

11

Diff. Laxity

Zero position line

15

AnteriorAnterior laxitylaxity : grade 2: grade 2

ATMC ATLC

2 D

2 C

2 B

2 A

AnteriorAnterior laxitylaxity : grade 3: grade 3

109

19

26

29

355

8

11

Diff. Laxity

Zero position line

15

3 D

3 C

3 B

3 A

ATMC ATLC

AnteriorAnterior laxitylaxity : grade 4 : grade 4

91

19

115

8

11

Diff. Laxity

zero position line

15

4 D

4 C

4 B

4 A

ATLCATMC

AnteriorAnterior laxitylaxity : grade 4 : grade 4

91

19

37

24

115

8

11

Diff. Laxity

zero position line

15

4 D

4 C

4 B

4 A

ATLCATMC

4 - A 4 - B 4 - C 4 - D3 - A 3 - B 3 - C 3 - D2 - A 2 - B 2 - C 2 - D1 - A 1 - B 1 - C 1 - D

AnteriorAnterior laxitieslaxities classificationclassification

Grade 4

Grade 3

Grade 2

Grade 1

ATMC (first number) : 4 grades

ATLC (A, B, C or D) : 4 grades

2.5 4.3 8.3 5. 48 4. 2 5.5 6.5

10.8 5.6 5.6 413.2 8 4 2

Grade 4

Grade 3

Grade 2

Grade 1

Number of cases for all categories ( % )

n = 487

AnteriorAnterior laxitieslaxities classificationclassification

A B C D

Prospective Prospective surgerysurgery

2 A 2 B 2 C 2 D1 A 1 B 1 C 1 D

isolated ACL ACL + extra-articularlateral reconstruction

Prospective Prospective surgerysurgery

4 A 4 B 4 C 4 D3 A 3 B 3 C 3 D2 A 2 B 2 C 2 D1 A 1 B 1 C 1 D

isolated ACL

ACL + medial + lateralACL + medial

ACL + extra articularlateral reconstruction

19 %

17 %38 %

26 %

Precice and objective measurement of preop and post-op laxity

PreoperativePreoperative ATMCATMC andand ATLC ATLC Post Post opop 10 10 yearsyears

"Mac InJones » procedure

QuadricipitalQuadricipital tendon tendon isis stretchedstretched fromfrom the condyle the condyle to the Gerdyto the Gerdy’’s tubercule s tubercule withwith solidsolid suturessutures

ACL reconstruction with patellar tendon

Evolution of Evolution of radiologicalradiological laxitylaxity afterafter surgerysurgery

0123456789

preop 6 m 1 year > 10 y

ATMCTACE

Gain for ATMC : 62 % Gain for ATMC : 62 % Gain for ATLC : 77 %Gain for ATLC : 77 %

DifferentialDifferential leftleft/right /right laxitylaxity

ACL reconstruction + lateral plasty : 100 cases

In the same way, a prospective study is started to evaluate postero-medial reconstruction

• Conclusive diagnosis for ACL rupture

• Better comprehension of laxity physiopathology

• Laxities classification

• Judicious surgical treatment adaptated to the lesions

ConclusionsConclusions

« Knee instability after injury to the anterior cruciate ligament

Quantification of the Lachman test »