7.0 mm Cannulated Screws. Part of
the Synthes Cannulated Screw System.
Technique Guide
Table of Contents
Introduction
Surgical Technique
Product Information
7.0 mm Cannulated Screws
2
AO Principles
3
Indications
4
Surgical Technique Tips
5
Percutaneous Technique
6
Open Technique
11
Implants
13
Instruments
14
Set List
17
Image intensifier control
Synthes
7.0 mm Cannulated Screws
Features
– Cannulated shaft accepts 2.0 mm diameter
guide wires (threaded and nonthreaded
wires available).
– Hemispherical head ensures optimal annular
contact with washers and Synthes plates when
screws are angled.
– Standard 3.5 mm hexagonal drive is compatible
with screwdrivers in other commonly used
Synthes sets.
– Reverse-cutting flutes assist in screw removal.
– Choice of thread lengths offers best fit of
threads into far bone fragment, for greater
interfragmentary compression.
– Cancellous thread profile uses deep cutting
threads with a large pitch to increase resistance
to pullout. The large pitch also accelerates
screw insertion and removal.
2.0 mm guide wire
8.0 mm diameter head
with 3.5 mm hex drive
Spherical underside
4.5 mm diameter shaft
Reverse-cutting flutes
Cancellous thread design
Thread lengths
16 mm thread
32 mm thread
Fully threaded
Materials
Implant quality
316L stainless steel
2
Synthes 7.0 mm Cannulated Screws
AO Principles
In 1958, the AO formulated four basic principles, which have
become the guidelines for internal fixation.1 These principles,
as applied to cannulated screws, are:
Anatomic reduction
A guide wire marks the prescribed path for the cannulated
screw and secures alignment of the fragments while the
screw is being inserted. The cannulated screw is inserted
over the wire and tightened to further compress the
fragments and hold the reduction.
Stable fixation
Cannulated screws provide interfragmentary compression
and absolute stability across the fracture. The screws are
available in different threads lengths, allowing the surgeon
to optimize purchase in the far fragment for maximum
compression and stability.
Preservation of blood supply
The use of small diameter guide wires allows precise placement of cannulated screws through small incisions. This
technique minimizes disruption of soft tissue and preserves
vascular blood flow for bone healing.
Early, active mobilization
Cannulated screws, combined with AO technique, provide
stable fracture fixation with minimal trauma to vascular
supply. This helps to create an improved environment for
bone healing, accelerating the patient’s return to previous
mobility and function.
1. M.E. Müller, M. Allgöwer, R. Schneider, and H. Willenegger. Manual of
Internal Fixation, 3rd Edition. Berlin: Springer-Verlag. 1991.
Synthes
3
Indications
7.0 mm Cannulated Screws
For fracture fixation of large bones and large bone fragments.
Warning: This device is not approved for screw attachment
or fixation to the posterior elements (pedicles) of the
cervical, thoracic or lumbar spine.
4
Synthes 7.0 mm Cannulated Screws
Surgical Technique Tips
Cleaning cannulations
Instruments
319.27
Cleaning Brush
319.36
2.0 mm Cleaning Stylet
Cleaning the cannulation in each instrument is imperative
for proper function. Instruments should be cleared intraoperatively with the 2.0 mm cleaning stylet to prevent accumulation
of debris in the cannulation and potential binding of the
instruments about the guide wire. Instruments should be
cleaned postoperatively with the stylet and the cleaning brush.
Drilling
Because of their hollow cross section and long length,
cannulated drill bits are more susceptible to breakage
than solid drill bits of the same diameter. Use less axial
force, avoid bending, and advance the drill bit slowly to
minimize the possibility of breakage. Cannulated drill bits
should be inspected after every procedure and replaced if
worn or damaged.
Synthes
5
Percutaneous Technique
1
Insert guide wire
Instruments
319.31
2.0 mm Trocar
319.32
4.5 mm / 2.0 mm Drill Sleeve
319.33
8.0 mm / 4.5 mm Drill Sleeve
319.34
11.0 mm / 8.0 mm Protection Sleeve
Make a stab incision and insert the percutaneous sleeve
assembly (11.0 mm /8.0 mm protection sleeve, 8.0 mm /
4.5 mm and 4.5 mm / 2.0 mm drill sleeves, and 2.0 mm
trocar) through the soft tissue to the bone. Remove the
trocar and insert a 2.0 mm threaded guide wire to the
appropriate depth. Confirm wire placement under image
intensification. Remove all sleeves.
Technique tips:
To prevent slippage, the 4.5 mm / 2.0 mm drill sleeve may be
tapped with a hammer to seat the teeth in the lateral surface.
Run the drill at maximum speed to minimize deflection while
gradually advancing the guide wire.
6
Synthes 7.0 mm Cannulated Screws
2
Insert additional parallel wires (if necessary)
Instruments
319.30
4.5 mm Parallel Drill Guide
319.31
2.0 mm Trocar
319.32
4.5 mm / 2.0 mm Drill Sleeve
Insert one 4.5 mm / 2.0 mm drill sleeve into the outer-most
4.5 mm hole of the parallel drill guide. Place this combination over the previously inserted guide wire and push directly
to the bone.
Insert a second 4.5 mm / 2.0 mm drill sleeve and the 2.0 mm
trocar into any of the other three holes in the parallel drill
guide and press the trocar to the near cortex. Remove the
trocar and insert a guide wire through the 4.5 mm / 2.0 mm
drill sleeve. Insert any additional guide wires following the
same procedure and then replace the drill guide with the
percutaneous sleeve assembly over one of the guide wires.
Technique tip: Avoid placing any bending forces on the first
guide wire, as this will affect parallelism.
Notes:
Any previously inserted guide wire can be used in the outermost hole of the guide for parallel placement of the next
guide wire.
Possible distances between parallel guide wires are 10 mm,
14 mm and 18 mm, measured from the center of the
primary hole of the parallel drill guide to the centers of
the other holes. Plan placement of each guide wire based
on these distances.
Synthes
7
Percutaneous Technique continued
3
Measure for screw length
Instruments
319.21
Cannulated Screw Measuring Device
319.32
4.5 mm / 2.0 mm Drill Sleeve
Remove the two inner drill sleeves. Slide the tapered end of
the cannulated screw measuring device over the guide wire.
This reading determines appropriate screw length. Select a
7.0 mm cannulated screw of this length, with a thread which
engages only the opposite fragment, and set it aside.
Note: Screw length will be 8 mm short of the guide wire tip
(the length of the threaded portion of the wire), preventing
penetration of the far cortex.
8
Synthes 7.0 mm Cannulated Screws
4
Predrill
Instruments
310.69
4.5 mm Cannulated Drill Bit
319.33
8.0 mm / 4.5 mm Drill Sleeve
Place the 8.0 mm / 4.5 mm drill sleeve into the protection
sleeve, and drill with the 4.5 mm cannulated drill bit under
image intensification to the appropriate depth, being careful
not to drill over the guide wire threads and penetrate the far
cortex. Remove the 8.0 mm / 4.5 mm drill sleeve.
Technique tip: Avoid directing the drill bit; let it follow the
guide wire. Take care to remove the drill bit slowly and to
pull back straight while running the drill forward to prevent
guide wire pullout.
Notes:
Depending on bone quality, the surgeon may choose to drill
only the near cortex to prevent inadvertent guide wire pullout.
The calibrations on the cannulated drill bits and the cannulated
tap are read at the surface of the bone and therefore can not
be used when using the percutaneous sleeves. Use image
intensification for confirmation of drilling and tapping depths.
Synthes
9
Percutaneous Technique continued
5
Tap
Instruments
311.69
Cannulated Tap for 7.0 mm Cannulated Screws
319.34
11.0 mm / 8.0 mm Protection Sleeve
Where necessary, tap the near cortex with the cannulated
tap through the protection sleeve. In dense bone, it may be
necessary to tap over the entire nonthreaded length of the
guide wire.
6
Insert screws
Instruments
314.19
Cannulated Hexagonal Screwdriver
319.34
11.0 mm / 8.0 mm Protection Sleeve
Using the cannulated hexagonal screwdriver without the
holding sleeve, insert the previously selected screw (Step 3)
through the protection sleeve. Remove and discard the
guide wire.
Note: In osteopenic bone, use a washer to prevent the screw
head from sinking into bone. Washers cannot be placed
through the percutaneous sleeve. Remove the sleeve before
placing the washer over the guide wire.
10
Synthes 7.0 mm Cannulated Screws
Open Technique
1
Insert guide wire
Instrument
312.71
Parallel Wire Guide
Place a positioning guide wire in the center of the femoral
neck. Place the parallel wire guide over the guide wire through
one of the central diamond-patterned positioning holes.
Notes:
The parallel guide’s position may be adjusted by replacing it
over the guide wire through one of the adjacent positioning
holes of the central diamond pattern.
The parallel guide does not need to lie flush with the bone.
2
Insert additional parallel wires (if necessary)
Instrument
312.71
Parallel Wire Guide
Under image intensification, insert a guide wire to the
desired depth through each of the outer triangle-patterned
placement holes.
Synthes
11
Open Technique continued
3
Remove guide wire
Remove the parallel guide and the positioning guide wire
(inserted in Step 1).
4
Insert screws
Measure, drill, tap and insert each screw before proceeding
to the next, to prevent loss of reduction.
12
Synthes 7.0 mm Cannulated Screws
Implants
7.0 mm Cannulated Screws, 16 mm thread length
– 30 mm–130 mm lengths in 5 mm increments
– 316L stainless steel
7.0 mm Cannulated Screws, 32 mm thread length
– 45 mm–130 mm lengths in 5 mm increments
– 316L stainless steel
Washers, 13.0 mm
– Prevents screw head from sinking into osteopenic bone
Synthes
13
Instruments
292.65
2.0 mm Threaded Guide Wire, 230 mm
310.19◊
2.0 mm Drill Bit, 100 mm, quick coupling
310.69◊
4.5 mm Cannulated Drill Bit, 233 mm,
Jacobs chuck
311.69
Cannulated Tap for 7.0 mm Cannulated
Screws
312.46
4.5 mm/3.2 mm Double Drill Sleeve
312.71
Parallel Wire Guide
◊ Available nonsterile or sterile-packed. Add S to catalog number for sterile product.
14
Synthes 7.0 mm Cannulated Screws
314.11
Holding Sleeve
314.19
Cannulated Hexagonal Screwdriver
319.21
Cannulated Screw Measuring Device
319.27
2.1 mm Cleaning Brush
319.30
4.5 mm Parallel Drill Guide
319.31
2.0 mm Trocar, 118 mm
Synthes
15
Instruments continued
319.32
4.5 mm/2.0 mm Drill Sleeve, 108 mm
319.33
8.0 mm/4.5 mm Drill Sleeve, 99 mm
319.34
11.0 mm/8.0 mm Protection Sleeve, 88 mm
319.36
2.0 mm Cleaning Stylet
319.97
Screw Forceps
16
Synthes 7.0 mm Cannulated Screws
7.0 mm Cannulated Screw Instrument and Implant Set (105.07)
Graphic Case
304.230
7.0 mm Cannulated Screw Instrument and
Implant Set Graphic Case
Instruments
292.65
2.0 mm Threaded Guide Wire, 230 mm, 10 ea.
◊
2.0 mm Drill Bit, 100 mm, quick coupling, 2 ea.
310.19
4.5 mm Cannulated Drill Bit, 233 mm,
310.69◊
Jacobs chuck, 2 ea.
311.69
Cannulated Tap for 7.0 mm Cannulated Screws
312.46
4.5 mm/3.2 mm Double Drill Sleeve
312.71
Parallel Wire Guide
314.11
Holding Sleeve
314.19
Cannulated Hexagonal Screwdriver
319.21
Cannulated Screw Measuring Device
319.27
2.1 mm Cleaning Brush
319.30
4.5 mm Parallel Drill Guide
319.31
2.0 mm Trocar, 118 mm, 2 ea.
319.32
4.5 mm/2.0 mm Drill Sleeve, 108 mm, 2 ea.
319.33
8.0 mm/4.5 mm Drill Sleeve, 99 mm
319.34
11.0 mm/8.0 mm Protection Sleeve, 88 mm
319.36
2.0 mm Cleaning Stylet
319.97
Screw Forceps
Note: For additional information, please refer to package insert.
For detailed cleaning and sterilization instructions, please refer to
http://us.synthes.com/Medical+Community/Cleaning+and+Sterilization.htm
or to the below listed inserts, which will be included in the shipping container:
—Processing Synthes Reusable Medical Devices—Instruments, Instrument Trays
and Graphic Cases—DJ1305
—Processing Non-sterile Synthes Implants—DJ1304
◊ Available nonsterile or sterile-packed. Add S to catalog number for sterile product.
Synthes
17
7.0 mm Cannulated Screw Instrument and Implant Set (105.07) continued
Implants
7.0 mm Cannulated Screws, 16 mm thread length
208.030
208.035
208.040
208.045
208.050
208.055
208.060
208.065
208.070
208.075
208.080
208.085
208.090
208.095
208.100
208.105
208.110
208.115
208.120
208.125
208.130
Length (mm)
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
Qty.
2
2
2
2
2
2
2
2
4
4
4
4
4
4
4
2
2
2
2
2
2
Note: For additional information, please refer to package insert.
18
Synthes 7.0 mm Cannulated Screws
7.0 mm Cannulated Screws, 32 mm thread length
209.045
209.050
209.055
209.060
209.065
209.070
209.075
209.080
209.085
209.090
209.095
209.100
209.105
209.110
209.115
209.120
209.125
209.130
219.99
Length (mm)
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
Qty.
2
2
2
2
2
2
2
2
2
2
2
2
2
1
1
1
1
1
Washer, for 4.5 mm Cortex and 6.5 mm
Cancellous Bone Screws, 6 ea.
Also Available
Small Battery Drive with 14.4 V Battery Pack Sets
105.954H
with Hudson Reduction Drive Unit
105.954M
with Modified Trinkle Reduction Drive Unit
105.954T
with Trinkle Reduction Drive Unit
105.957
Power Drive Set
Instruments
292.651
292.652
292.656
310.79
314.22
314.27
304.234
304.235
360.02◊
2.0 mm Threaded Guide Wire, spade point
both ends, 230 mm
2.0 mm Non-Colored Threaded Guide Wire,
spade point, 230 mm
2.0 mm Non-Threaded Guide Wire,
spade point one end, 230 mm, blue
Cannulated Countersink, for 7.0 mm
Cannulated Screws
Cannulated 3.5 mm Hexagonal Screwdriver
Shaft, for 7.0 mm Cannulated Screws
Large Hexagonal Screwdriver, for removal
of 7.0 mm Cannulated Screws
Screw Rack for 7.0 mm Cannulated Screws,
16 mm and 32 mm Threaded
Screw Rack for 7.0 mm Cannulated Screws,
fully threaded
7.0 mm Cannulated Drill Bit, large quick
coupling, 90 mm
Implants
208.135–
208.150
209.135–
209.150
209.420–
209.530
7.0 mm Cannulated Screws
16 mm thread length, 135 mm–150 mm
(5 mm increments)
32 mm thread length, 135 mm–150 mm
(5 mm increments)
fully threaded, 20 mm–130 mm
(5 mm increments)
◊ Available nonsterile or sterile-packed. Add S to catalog number for sterile product.
Synthes
Synthes (USA)
1302 Wrights Lane East
West Chester, PA 19380
Telephone: (610) 719-5000
To order: (800) 523-0322
Fax: (610) 251-9056
© 1997 Synthes, Inc. or its affiliates. All rights reserved.
Synthes (Canada) Ltd.
2566 Meadowpine Boulevard
Mississauga, Ontario L5N 6P9
Telephone: (905) 567-0440
To order: (800) 668-1119
Fax: (905) 567-3185
Synthes is a trademark of Synthes, Inc. or its affiliates.
www.synthes.com
Printed in U.S.A.
9/10
J2425-G