Title: J.L Lerat, B. Moyen, I. B
1INNEX-Knee The Lyon experience
- J.L Lerat, B. Moyen, I. Bénareau
- E. Berthonnaud, J. Dimnet
- Service de Chirurgie Orthopédique
- Laboratoire de Biomécanique du Mouvement
- Centre Hospitalier Lyon-Sud
2INNEX-Knee The Lyon experience
- J.L Lerat, B. Moyen, I. Bénareau
- E. Berthonnaud, J. Dimnet
- Service de Chirurgie Orthopédique
- Laboratoire de Biomécanique du Mouvement
- Centre Hospitalier Lyon-Sud
Aim of the presentation 1 - Preliminary
results (1 to 3 years) 2 - Anterior-posterior
laxity 3 - Mobility of the plateau
3INNEX-Knee The Lyon experience
- 1st Pilot study (April 1998 - Nov. 1998)
- Innex knee cemented femur and tibia
- 30 cases (20 CR - 10 PS)
4INNEX-Knee The Lyon experience
- 1st Pilot study (April 1998 - Nov. 1998)
- Innex knee cemented femur and tibia
- 30 cases (20 CR - 10 PS)
- 2nd Pilot study (Nov. 1999 - 0ct. 2000)
- Innex knee non cemented femur
- 20 cases (10 CR - 10 UCOR)
- further experience 23 cases
5INNEX-Knee The LYON experience
- 73 cases
- 44 F - 29 M
- Age 69 10 years (26-88)
- Etiology
- 2 R. A, 1 SVNH
- 2 hemophilic arthropathies
- 1 Pagets disease
- 68 gonarthrosis
- - 14 previous osteotomies
- - 6 previous surgery (2 ACL,1 fract, 2
patella)
Some cases are particularly difficult for a pilot
study
6INNEX-Knee
- These difficulties explain
- Op. time 90 mn 19 (55-145)
- Tibial tuberosity ost 10 cases
- Immediate weight bearing
- Discharge 7 days
- Flexion after 7 days 80
7INNEX-Knee
-
- PCL preservation 42
- Postero-stabilisation 12
- UCOR 19
- PCL normal 73 (100 )
- ACL normal 45 (61.5 )
- ACL ruptured 28 (38.5 )
8Complications
- 1 Reflex Sympathic Dystrophy
- 11 Deep Veinous Thombosis
- 1 fracture of tibial tubercule (fall in stairs
after 1 month) - 1 skin necrosis (after 8 op with 7 skin
incisions arthrodesis) - 0 infection
- 4 Manipulations under Gen. anest.
9Functional results
n 30 cases (1 year)
- Internat. Knee Society Score
- (200 pts)
- Pre op 116 27 (50-173)
- Post op 184 24 (87-200)
- Bad 1
- Correct 7
- Good 20
- Excellent 73
10Mobility
After 2 months n 66
- Flexion 106 18
- (45 - 140)
- Extension 0 55 cas
- - 5 6 cas
- -10 5 cas
- 45-80 5
- 85-95 8
- 100-105 12
- 110-115 14
- 120-125 16
- 130-135 9
- 135-140 2
11Mobility
Follow-up 1 year n 34
- Flexion 112 18
- (45 - 140)
- Extension -1 3
- 0 29 cases
- - 5 2 cases
- -10 3 cases
- 45-80 2
- 90-95 2
- 100-105 4
- 105-110 6
- 110-120 4
- 120-125 7
- 125-130 3
- 130-140 6
12Mobility
Follow-up 1 year n 34
112 18
- 45-80 2
- 90-95 2
- 100-105 4
- 105-110 6
- 110-120 4
- 120-125 7
- 125-130 3
- 130-140 6
gt 120 47
13(No Transcript)
14Anatomical results
HKA mechanical axis
postop
preop
H
Varus knees (n 60) HKA 172 5 (160 -
180)
Varus HKA 179 2 (173 - 186) 178 to
182 88
K
A
15Anatomical results
postop
preop
H
Varus knees (n 60) HKA 172 5 (160 -
180) Valgus knees (n 13) HKA 184
3 (181 - 189)
varus HKA 179 2 (173 - 186) Valgus HKA
180 3 (178 - 184)
K
A
16Precision of the cuts
F (femur A-P) 90 1 T (tibia A-P) 89
2 Femur lateral 88 2 Tibia lateral 87
2
n71
17Distal fémoral cut
F angle 90 1
- 87 1
- 88 8
- 89 10
- 90 27
- 91 10
- 92 11
- 93 4
- n 71
F
18Distal femoral cut
F angle 90 1
- 87 1
- 88 8
- 89 10
- 90 27
- 91 10
- 92 11
- 93 4
- n 71
93
F
19 HKS angle 6 2
Important pre operative measurement to do a
precise distal cut
H
- 2 1 case
- 3 2
- 4 6
- 5 29
- 6 14
- 7 9
- 8 6
- 9 2
- 10 2
- 11 2
- n 73
S
K
20 Tibial cut
T angle 89 2
- 85 1
- 86 1
- 87 9
- 88 14
- 89 8
- 90 25
- 91 7
- 92 3
- 93 3
- n 71
21 Tibial cut
T angle 89 2
- 85 1
- 86 1
- 87 9
- 88 14
- 89 8
- 90 25
- 91 7
- 92 3
- 93 3
- n 71
81
22Position of the components
- Inclination of femoral component F lateral
- 88 2
- 85 11
- 86 7
- 87 13
- 88 8
- 89 5
- 90 24
- 92 1
- n 71
23The intramedullary axis is not always the
recommended guide for anterior and posterior
cuts Sometimes, metaphyseal axis should be better
24Position of the components
Inclination of tibial component T lateral
82 2 83 3 84 9 85 5 86
9 87 18 88 9 89 1 90 11 91 3
Instrumentation takes into account the mean
anatomical slope 6 (or 84)
87 2
25Position of the components
Inclination of tibial component T lateral
82 2 83 3 84 9 85 5 86
9 87 18 88 9 89 1 90 11 91 3
The difference comes probably from the fact that
the measurements are done on short X-ray films
and not on the complete tibia
87 2
26In conclusion, the precision of the cut is
satisfactory All the cases are included (learning
curve)
Other TKAs INNEX-knee
N 73
901 882
892 872
no difference between Innex and other types of
TKR in our experience
27Patella
- 64/73 without resurfacing
- Thickness of bone 22 2 mm
- 9 patella resurfaced
- Blackburn index p. op 0.76 0.16
- Patella centered 68 cases
- Subluxation (1 to 3 mm) 5 cases
Only 1 case of secondary patellar resurfacing
28Patella
- 9 patellar resurfacing (12 )
- Thickness of bone 22 2 mm
- Post-op thickness of bone 14 1 mm
29Interest of the CSTI used successfully with the
Natural knee
530 knees follow-up max. 4.5 Y
CSTI
30The short stem of Innex is an advantage in TKA
after osteotomy
UCOR
31In case of severe valgus after HTO the short stem
of Innex permits to associate TKR and a new
osteotomy in the same time
32Innex CR osteotomy
Extension Post drawer Ant drawer
33Second part
- Study of anterior and posterior drawer
- Study of the mobility of MB
- Anterior-posterior translation during flexion
- Anterior-posterior translation during
radiological drawer-test - Rotation
34Radiological anterior drawer
- Flexion 20
- 9 kg load
- Free translation
- Free rotation
Knee instability after injury to the anterior
cruciate ligament Quantification of the Lachman
test JL Lerat, B Moyen, F Cladière, JL Besse, H
Abidi J. Bone Joint Surgery VOL. 82-B, N1,
January 2000, 42-47.
35Radiological anterior drawer
- Flexion 20
- 9 kg load
- Free translation
- Free rotation
Anterior drawer 6.5 5.4 mm (6-16) n 34
36Posterior drawer
Test used for PCL rupture Lateral view with
harmstrings contracted Flexion 70
Posterior drawer 7.3 4.7 mm (1-15) n 65
37UCOR
Post drawer Ant drawer
Post drawer 10 mm 4 Ant drawer
4.3 mm 5
n 14 n 10
38Study of the mobility of mobile bearing
Anterior-posterior translation
39Combination of translation and rotation
40- Study of the position of the Mobile plateau
- In full extension in one leg standing position
- At 30 of flexion in one leg standing position
- AT 50-60 of flexion in one leg standing position
41Mobility of mobile bearing
Extension in standing position
n 40
The MB is situated post. to metal 2.2 2.4 mm
33 cases posteriorly (3.4 mm) 7 cases
anteriorly (3.7 mm)
42Flexion 30 in standing position
n 21
The MB is situated post to metal 2.7 2.4 mm
17 cases behind (4 mm) 4 cases before (3 mm)
43Flexion 50 in standing position
n 9
The plateau is always situated post to metal
4.3 2.7 mm
44Position of the mobile bearing in ant. and post.
drawer
- Post drawer 7.3 4.7 mm
- M B situated 1.7 mm post to metal
- 35 cases post 4.5 mm
- 18 cases ant 2.8 mm
- n 53 cases
- Ant drawer 6.5 5.4 mm
- M B situated 4 mm post. to metal
- 3 cases ant 2.5 mm
- 24 cases post 4.4 mm
- n 24 cases
45Total A-P translation of Mobile Bearing 5.7
3.9 mm (0.5 - 14.2) range 13.7 mm
Posterior drawer Anterior drawer
46X-ray Mobility StudyINNEX CR INNEX UCORE.
Berthonnaud, J. DimnetLaboratoire de
Biomécanique du mouvementCentre Hospitalier
Lyon-Sud
47Study of the rotation - Preliminary results
3 balls in the polyethylene
48Calculation of the PE mobility with one X-ray
X-ray plate
INNEX with 3 steel balls embedded in the PE
.
X-ray source
Known - Distance between X-ray source and X-ray
plate.- Position of the X-ray source on the
X-ray.
Known - The size of the INNEX (tibial base
plate) - The interdistances between balls in PE.
Measured The position of rotation axis The
position of the balls The position of the tibial
plots
Calculated - The rotation ? between the PE and
the tibial base plate. - The translation t
between the PE and the tibial base plate.
49Mobility of the PE plateau vs tibial
component(first results)
Total amount of rotation from full extension to
50 of flexion in standing position
The study is just starting and should be
multicentric
501 an
Tiroir antérieur et pente tibiale favorisant la
bascule