Synthes LISS DF User manual

LISS DF. The less invasive stabilization
system for distal femur fractures.
Technique Guide
This publication is not intended for
distribution in the USA.
Instruments and implants
approved by the AO Foundation

Introduction
Surgical Technique
Product Information
Bibliography 44
Less Invasive Stabilization System LISS 2
AO Principles 4
Indications 5
Clinical Cases 6
Preoperative Planning 8
Preparation 11
Plate Insertion 16
– Option A Insertion of Self-Drilling Monocortical Screws 20
– Option B Insertion of Self-Tapping Bicortical Screws 25
– Option C Insertion of Periprosthetic Screws 29
– Option: Pulling Device (“Whirly Bird”) 32
Implant Removal 33
Tips 35
Instruments for Minimally Invasive Surgery 36
Implants 37
Instruments 39
Sets 42
Image intensifier control
Warning
This description is not sufficient for immediate application of the instrumentation.
Instruction by a surgeon experienced in handling this instrumentation is highly
recommended.
Processing, eprocessing, Care and Maintenance
For general guidelines, function control and dismantling of multi-part instruments,
as well as processing guidelines for implants, please contact your local sales
representative or refer to: www.synthes.com/reprocessing
Table of Contents
DePuy Synthes 1
Stardrive
Hex drive

2 DePuy Synthes LISS DF Technique Guide
LISS DF. The less invasive stabilization
system for distal femur fractures.
Less invasive procedure
− A radiolucent handle facilitates the
insertion of the plate as well as accu-
rate and hassle-free percutaneous
placement of the screws.
− Additional instrumentation facilitate
indirect reduction.
Anatomically precontoured low
profile plates
–Intended to reduce soft tissue
problems
– No need for plate contouring
Note: Excessive and repetitive bending is not
recommended as it may weaken the plate.
Angular stability
– Prevents screw loosening as well
as primary and secondary loss
of reduction
– Allows early functional mobilization
– As an internal fixator the plate
preserves bone vascularization
– Offers improved purchase in osteo-
porotic bone
Wide variety of screws
– Self-tapping or self-drilling locking
screws
– Periprosthetic locking screws with
blunt tip for periprosthetic fractures
– Cortex screws
– Available in stainless steel and
titanium
Wide variety of anatomically
precontoured plates
– LCP DF and PLT plates
– Available in stainless steel and
titanium alloy (TAN)
– Left and right versions
– LCP DF plates in eight lengths with
5 to 19 holes in the shaft
– Long LCP DF plates (15 to 19 holes)
available in sterile only

DePuy Synthes 3
LISS instrumentation for Stardrive
and Hex drive
The torque-limiting screwdriver, the
screwdriver shaft and the cleaning
instrument are available for screws with
Stardrive and Hex drive.

4 DePuy Synthes LISS DF Technique Guide
In 1958, the AO formulated four basic principles, which have
become the guidelines for internal fixation:1
Anatomic reduction
Fixation of extra- and intra-articular distal femur fractures
with the precontoured LCP DF plates allows for anatomic
reduction.
Stable fixation
Locking holes allow fixation with locking screws for angular
stability. A fixed-angle construct is advantageous in osteo-
porotic bone and multifragment fractures where traditional
screw purchase is compromised.
Preservation of blood supply
The LISS approach with its proven success preserves the
blood supply through a minimally invasive surgical technique
and minimal bone-to-plate contact.
Early, active mobilization
LISS provides stable fracture fixation with minimal trauma to
the vascular supply. This helps improve the environment for
bone healing, accelerating the patient’s return to previous
mobility and function.
AO Principles
1Müller ME, Allgöwer M, Schneider R, Willenegger H (1991) AO Manual of
Internal Fixation. 3rd Edition. Berlin: Springer

DePuy Synthes 5
Indications
LCP DF is indicated for the stabilization of fractures of the
distal femur. These include:
− Distal shaft fractures
−Supracondylar fractures
− Intra-articular fractures
− Periprosthetic fractures
Indications

6 DePuy Synthes LISS DF Technique Guide
Case 1
Male, 20 years old, poly-
trauma, fracture 33-C3
Clinical Cases
Preoperative Follow-up after 6 weeks
Follow-up after 3 months Follow-up after 5 months

DePuy Synthes 7
Case 2
Male, 76 years old, isolated
fracture 33-B2
Preoperative Postoperative
Follow-up after 4 weeks

LCP Distal Femur, right
Titanium St. Steel Holes Length (mm)
422.250 222.250 5 156
422.252 222.252 7 196
422.254 222.254 9 236
422.256 222.256 11 276
422.258 222.258 13 316
04.124.030S 02.124.030S 15 356
04.124.034S 02.124.034S 17 396
04.124.038S 02.124.038S 19 436
ED/F AC/G B
12345678910 11 12 13
FE/A/B
GC
D
034.000.315 AB 30100466 © 09/2010 Synthes, Inc. or its affiliates All rights reserved Synthes is trademark of Synthes, Inc. or its affiliates Ö034.000.315öAB{ä
Synthes GmbH
Eimattstrasse 3
CH-4436 Oberdorf
www.synthes.com
14 15 16 17 18 19
18 19
16 17
14 15
1213
11
10
89
67
45
23
B
1
E
DF
A
CG
0 10 20 30 40 50 60 70 80 90 100 mm
1.10 Magnification
Caution: Due to variable magnification factors in x-rays,
this template should be used for general pre-operative planning only.
For use only with the Original AO System of
Instruments and Implants
LCP Distal Femur, left
ED/F AC/G B
12345678910 11 12 13
DB/A/E
CG
F
Titanium St. Steel Holes Length (mm)
422.251 222.251 5 156
422.253 222.253 7 196
422.255 222.255 9 236
422.257 222.257 11 276
422.259 222.259 13 316
04.124.031S 02.124.031S 15 356
04.124.035S 02.124.035S 17 396
04.124.039S 02.124.039S 19 436
034.000.320 AB 30100466 ©06/2010 Synthes, Inc. or its affiliates All rights reserved Synthes is trademark of Synthes, Inc. or its affiliates Ö034.000.320öABNä
Synthes GmbH
Eimattstrasse 3
CH-4436 Oberdorf
www.synthes.com
14 15 16 17 18 19
1819
16 17
14 15
12 13
10 11
89
67
45
23
CG
B
1
E
DF
A
010 20 30 40 50 60 70 80 90 100 mm
1.10 Magnification
Caution: Due to variable magnification factors in x-rays,
this template should be used for general pre-operative planning only.
For use only with the Original AO System of
Instruments and Implants
8 DePuy Synthes LISS DF Technique Guide
Preoperative Planning
Use the x-ray templates for LCP DF (Art. No. 034.000.315 for
right and 034.000.320 for left femur) to determine the
length of the plate and the position of the screws.
Preoperative planning of lag screws may be necessary.

DePuy Synthes 9
Preoperative screw-length selection using an AP
radiograph
To select the proper screw length for the condyle, it is possi-
ble to perform a preoperative x-ray with the 50 mm wide
calibrator and to use the table below.
1. Place the x-ray calibrator medially or laterally at the height
of the condyle.
2. Take an AP radiograph of the distal femur.
3. Measure the width of the x-ray calibrator (XRC) on the
radiograph.
4. Measure the maximum condyle width (MCW) on the
radiograph.
5. Determine the real condyle width (RCW).
6. Determine the screw lengths for the screw holes A to G
using the table below. The positions A to G are indicated
on the x-ray template and on the LISS DF insertion guide.
Length of locking screws (mm)
RCW = 50
XRC
⫻MCW
Real condyle
width (RCW)
60 – 80 mm
81 – 87 mm
88 – 95 mm
96 –110 mm
Hole
A
65
75
75
85
Hole
B
40
40
55
65
Hole
C
40
55
65
75
Hole
D
55
65
65
75
Hole
E
65
75
75
75
Hole
F
65
75
75
85
Hole
G
55
65
75
85

10 DePuy Synthes LISS DF Technique Guide
Example
The length of the x-ray calibrator on the radiograph (XRC) is
55 mm (magnification 1.10).
The maximum condyle width on the radiograph (MCW)
amounts to 91 mm.
Preoperative Planning
RCW= 50
55 ⳯91 = 83 mm
The real condyle width (RCW) is therefore 83 mm.
The screw lengths are therefore:
Screw hole Screw length (mm)
A 75
B 40
C 55
D 65
E 75
F 75
G 65
Important: The proper placement of the plate on the
condyle is essential to ensure the correct screw length.

DePuy Synthes 11
Preparation
1
Prepare required sets
Instrument sets
01.120.040 Set for LISS Instruments and
or Insertion Handle, for DF and PLT Plates
01.120.041 Set for LISS Instruments Stardrive
and Insertion Handle, for DF and PLT
Plates
Optional instrument set
01.120.457 Large Fragment Instrument Set
Plate sets
01.120.332 Plate Set LCP DF 4.5/5.0 (Stainless
or Steel)
01.120.334 Plate Set LCP DF 4.5/5.0 (TAN)
Note on long plates: The LCP DF plates with
15 to 19 holes are available in sterile only and not part
of a set. Therefore these articles have to be ordered
as single items (for article numbers refer to page 37).
Screw sets
68.122.050 Modular Insert, for Modular Screw Rack,
for Screws ⭋5.0 mm, size 1/3, without
Contents, Vario Case System
68.122.051 Modular Insert, for Modular Screw Rack,
for Screws ⭋4.5 mm, size 1/3,
without Contents, Vario Case System
68.122.052 Modular Insert, for Modular Screw Rack,
for Screws ⭋6.5 mm, size 1/3,
without Contents, Vario Case System
68.122.054 Modular Screw Rack, with Drawer,
Measuring Block and Lid, length 200 mm,
height 115 mm, size 1/2, without
Contents, Vario Case System
Power Tools*
511.701 Compact Air Drive II
511.750 AO/ASIF Quick Coupling, for Compact
Air Drive and Power Drive
511.790 Quick Coupling for irschner Wires
⭋0.6 to 3.2 mm, for Compact Air Drive
and Power Drive
05.001.201 Battery Handpiece, modular,
for Trauma Recon System
05.001.202 Power Module, for Trauma Recon System
05.001.203 Sterile Cover, for Trauma Recon System
05.001.227 Lid for Battery Handpiece No. 05.001.201,
for Trauma Recon System
05.001.205 AO/ASIF Quick Coupling,
for Trauma Recon System
05.001.212 Quick Coupling for irschner Wires
⭋1.0 to 4.0 mm, for Trauma Recon
System
05.001.216 Torque Limiter, 4.0 Nm, for Trauma
Recon System
* For further information refer to the instructions for use for the Trauma Recon
System (036.000.505) or the Compact Air Drive (036.000.064).

12 DePuy Synthes LISS DF Technique Guide
2
Position the patient
Position the patient supine on a radiolucent table. The leg
should be freely movable. The contralateral leg can be placed
in an obstetric leg holder. Place the knee joint line slightly
distal to the hinged part of the table to allow flexion of the
knee during surgery.
Avoid too strong a traction and a fully extended knee, as the
forces of the gastrocnemius muscle would draw the distal
fragment into recurvatum. This does not only make the re-
duction of the fracture difficult, but also endangers the po-
pliteal artery and vein.
In very short distal fragments, it is recommended to flex the
lower leg to approximately 60°. This also reduces the traction
force of the gastrocnemius muscle.
Preparation

1
2
345
DePuy Synthes 13
3
Assemble the insertion instruments
Instruments
324.011 LISS Insertion Guide for Distal Femur, left
or
324.012 LISS Insertion Guide for Distal Femur,
right 1
321.170 Pin Wrench ⭋4.5 mm 2
324.022 Drill Sleeve for LISS Insertion Guide 3
324.044 Stabilization Bolt for LISS Insertion Guide 4
324.043 Fixation Bolt for LISS Insertion Guide 5
Note: In certain cases (e.g. distal fracture treated with a
short plate) it may be advantageous to do the surgery
without using the LISS insertion guide and the corresponding
LISS instruments. Then, screws can be inserted by applying
the technique described in the LCP Instructions for Use
036.000.019.
Insert the fixation bolt in hole A of the insertion guide.
Place the insertion guide on the three-point locking
mechanism of the plate.
Hole A

Hole B Hole A
14 DePuy Synthes LISS DF Technique Guide
Thread the fixation bolt into the plate. Thread the nut of the
fixation bolt and lightly tighten it with the pin wrench.
For a more stable fixation of the plate on the insertion guide
during insertion, introduce the stabilization bolt with the drill
sleeve in hole B and thread it into the plate.
Note: To prevent tissue ingrowth and facilitate implant
removal, close the unoccupied screw holes with screw hole
inserts prior to inserting the plate. Use the torque-limiting
screwdriver. The optimum torque is reached after one click.
Preparation

DePuy Synthes 15
4
educe the fracture
In an intra-articular fracture, first reconstruct and stabilize the
entire joint. The figure shows the possible positioning sites
for lag screws in the condyles (in red).
Take care to ensure that these lag screws will not collide with
the screws inserted through the insertion guide.
The fracture can be aligned manually by traction using a
temporary knee-bridging external fixator or a distractor. In-
traoperative x-ray or image-intensifier control is recommen-
ded to check the reduction.
The anteromedial insertion of a Schanz screw can be benefi-
cial in distal fragment manipulation.
5
Surgical approaches
Extra-articular fractures
Perform a skin incision from Gerdy’s tubercle about 80 mm in
a proximal direction. Split the iliotibial tract in the direction of
the fibres. Open the space between the lateral vastus and
the periost. Distally, the lateral vastus muscle inserts mainly
on the femoral ridge. There are no muscle insertions on the
lateral periost or bone. The plate can be inserted into the
space between the periost and the muscle.
Intra-articular fractures
In intra-articular fractures, an anterolateral arthrotomy provi-
ding good control of the reduction is recommended. This
arthrotomy also allows a subsequent insertion of the plate
and can be used to insert lag screws from medially.
Possible positioning sites for lag screws (in red)

16 DePuy Synthes LISS DF Technique Guide
1
Insert LISS
Instruments
Assembled Insertion Guide
324.027 Trocar, length 162 mm, for No. 324.022
Use the assembled insertion guide to insert the plate be-
tween the lateral vastus muscle and the periost. Slide the
plate proximally and ensure that its proximal end remains in
constant contact with the bone. Position the distal end of
the plate against the lateral condyle. To find the correct posi-
tion, move the plate proximally and then back distally until
the plate fits the condyle. Should the proximal end of the
handle and the soft tissues impair the insertion of the plate,
it is possible to remove the radiolucent proximal part of the
handle for insertion.
Plate Insertion
Due to its weight, the insertion guide tends to tilt dorsally. If
the insertion guide points parallel to the floor with the pa-
tient in a supine position, the plate is externally rotated and
no longer lies flat up against the lateral condyle. The fixation
bolt must be oriented parallel to the patello-femoral joint.
Consequently, the insertion guide shows an internal rotation
of about 10°. This occurrence is also visible in the AP view of
an image intensifier. The plate must lie flat up against the
condyle to ensure an optimal fit on the bone.

DePuy Synthes 17
Once the plate is properly aligned with the bone, remove the
drill sleeve and stabilization bolt from hole B. Insert the trocar
through the drill sleeve in the most proximal hole of the
plate. Perform a stab incision and push the drill sleeve and
the trocar down to the plate. Check the correct position of
the proximal part of the plate, either with the image intensi-
fier or by direct palpation.
Option: Check plate position with a Kirschner Wire
Instrument
292.699 irschner Wire ⭋2.0 mm with threaded tip
Use a irschner wire to check the correct position of the
proximal part of the plate on the bone.
Secure the position of the drill sleeve with the lateral screw
on the insertion guide. Replace the trocar with a stabilization
bolt. To close the frame, thread the stabilization bolt into the
plate.
Note: Due to soft tissues around the stabilization bolt, it will
be difficult to change the position of the plate/handle assem-
bly once the bolt has been inserted.

18 DePuy Synthes LISS DF Technique Guide
2
Fixate LISS temporarily with Kirschner wires
Instrument
292.699 irschner Wire ⭋2.0 mm
with threaded tip
For preliminary fixation of the plate, use 2.0 mm irschner
wires through the fixation and stabilization bolts.
Carefully check the position of the plate and the length of
the reduced injured limb. Once the reduction has been
successfully completed and the plate has been positioned
correctly, the locking screws can be inserted.
Plate Insertion