Stress-radiography of the knee Stress-radiography of the knee Anterior and posterior translation Anterior and posterior translation

at 20° of flexion at 20° of flexion in 563 normal kneesin 563 normal knees

and 487 ACL deficient knees and 487 ACL deficient knees

Stress-radiography of the knee Stress-radiography of the knee Anterior and posterior translation Anterior and posterior translation

at 20° of flexion at 20° of flexion in 563 normal kneesin 563 normal knees

and 487 ACL deficient knees and 487 ACL deficient knees

JL. LERAT, JL. BESSE, F. CHOTEL, F. CLADIERE, B. MOYEN JL. LERAT, JL. BESSE, F. CHOTEL, F. CLADIERE, B. MOYEN

Department of Orthopaedic Surgery and Sports MedicineDepartment of Orthopaedic Surgery and Sports Medicine

Lyon – FranceLyon – France

ESSKA, Nice, 5-1998

EFORT, Bruxelles 3-8 June 1999

Aims of the studyAims of the study

• The measurements of anterior and posterior laxity The measurements of anterior and posterior laxity – in normal kneesin normal knees– and in ACL deficient kneesand in ACL deficient knees

• Diagnosis valueDiagnosis value

• Grading the knee play in order to choose adaptated Grading the knee play in order to choose adaptated

surgerysurgery

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

Anterior stress-radiographyAnterior stress-radiography

TORG introduced the "LACHMAN test"

in 1976

Test practised since 1963 byTRILLAT in Lyon-France

Anterior stress-radiographyAnterior stress-radiography

Anterior stress-radiographyAnterior stress-radiography

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

apparatus

l

apparatus

Manualy

Anterior and posterior stress-radiographyAnterior and posterior stress-radiography

The same apparatus is used for both anterior and posterior tests

• 20° of flexion20° of flexion• Fixed load (9 kg)Fixed load (9 kg)• Free translationFree translation• Free rotationFree rotation• Comfortable for the Comfortable for the

patientspatients

Anterior translation of the tibiaAnterior translation of the tibia

• Posterior tibial cortexPosterior tibial cortex

as reference lineas reference line

• Parallels tangent to the Parallels tangent to the posterior aspect of the posterior aspect of the condylescondyles

• Distance between these Distance between these tangent lines and the tangent lines and the

tibial compartmentstibial compartments

ATMC: ATMC: Anterior Translation of Medial CompartmentAnterior Translation of Medial Compartment

ATLC : ATLC : Anterior Translation of Lateral CompartmentAnterior Translation of Lateral Compartment

LandmarksLandmarks

Lateral condyle : anterior notch and posterior angle

ATMC

ATLC

ATMCATMC and and ATLCATLC

Anterior radiological drawerAnterior radiological drawer

PTMCPTMC = = Posterior Translation of Medial CompartmentPosterior Translation of Medial Compartment

PTLC = PTLC = Posterior Translation of Lateral CompartmentPosterior Translation of Lateral Compartment

Posterior translation of the tibiaPosterior translation 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 correlation for 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

• specificity = 90 %specificity = 90 %• sensitivity = 87 %sensitivity = 87 %• predict posit. val = 89 %predict posit. val = 89 %• predict negat. val = 88 %predict negat. val = 88 %

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

ATMCATMC ATLCATLC

Cut point : 6 mm Cut point : 11.5 mm

Diagnosis of ACL rupture Diagnosis of ACL rupture The ATMC is the most reliable The ATMC is the most reliable

.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

Sensitivity

Medial

Compartment

PTMC +ATMC

4.2 ± 2.7 mm

Physiological ant-post laxity Physiological ant-post laxity

Lateral Compartiment

PTLC +ATLC

12.2 ± 4.5 mm

Medial

Compartment

PTMC +ATMC 12.1 ± 4.5 mm

Pathological ant-post laxity Pathological ant-post laxity

Lateral Compartiment

PTLC +ATLC 19.4 ± 5.5 mm

Considering differential laxity

Pathological Pathological ATMCATMC and and ATLC ATLC Normal contralateral kneeNormal contralateral knee

ACL deficient knees : differential ant. translationACL deficient knees : differential ant. 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 side can be predominent

internal tibial rotation

Anterior laxities classificationAnterior laxities classification

• Translation of the medial side can be predominent

external tibial rotation

< 5mm

5-8mm

8-11mm

>11mm

05

1015202530

< 5mm

5-8mm

8-11mm

>11mm

Anterior laxities classificationAnterior laxities classification

ATMCATMC

Casesnumber

%

Anterior laxities : grade 1Anterior laxities : grade 1

5

8

11

Diff. Laxity mm

zero position line

15

Anterior laxities : grade 1Anterior laxities : grade 1

1285

8

11

Diff. Laxity

zero position line

15ATMC

knees

Anterior laxities : grade 1Anterior laxities : grade 1

128 595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

Anterior laxities : grade 1Anterior laxities : grade 1

128

36

595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

Anterior laxities : grade 1Anterior laxities : grade 1

128

36

22

595

8

11

Diff. Laxity

zero position line

15ATMC ATLC

1 D

1 C

1 B

1 A

Anterior laxities : grade 1Anterior laxities : 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

48

5

8

11

Diff. Laxity

Zero position line

15

Anterior laxity : grade 2Anterior laxity : grade 2

ATMC ATLC

2 D

2 C

2 B

2 A

Anterior laxity : grade 3Anterior laxity : 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

Anterior laxity : grade 4 Anterior laxity : grade 4

91

19

115

8

11

Diff. Laxity

zero position line

15

4 D

4 C

4 B

4 A

ATLCATMC

Anterior laxity : grade 4 Anterior laxity : 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

Anterior laxities classificationAnterior laxities classification

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. 4

8 4. 2 5.5 6.5

10.8 5.6 5.6 4

13.2 8 4 2

Grade 4

Grade 3

Grade 2

Grade 1

Number of cases for all categories ( % )

n = 487

Anterior laxities classificationAnterior laxities classification

A B C D

Prospective surgeryProspective surgery

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

isolated ACL ACL + extra-articular lateral reconstruction

Prospective surgeryProspective surgery

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 articular lateral reconstruction

19 %

17 %38 %

26 %

Precice and objective measurement of preop and post-op laxity

Preoperative Preoperative ATMCATMC and and ATLC ATLC Post op 10 yearsPost op 10 years

"Mac InJones » procedure

Quadricipital tendon is stretched from the condyle Quadricipital tendon is stretched from the condyle to the Gerdy’s tubercule with solid suturesto the Gerdy’s tubercule with solid sutures

ACL reconstruction with patellar tendon

Evolution of radiological laxity after surgeryEvolution of radiological laxity after surgery

0

1

2

3

4

5

6

7

8

9

preop 6 m 1 year > 10 y

ATMCTACE

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

Differential left/right laxityDifferential left/right laxity

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

THANK YOU

Medial laxity : what i do ?

1/Tensioning of distal insertion

2/ Tensioning of proximal insertion

3/ Tension without detaching the distal and proximal insertionsusing semi tendinosus or quadricipital tendon

3/ Tension without detaching the distal and proximal insertions