Synthes DFN User manual

DFN Distal Femoral Nail
Surgical Technique
Standard Locking
Spiral Blade Locking
Original Instruments and Implants of the Association
for the Study of Internal Fixation – AO/ASIF

399.430 Hammer 700 g
351.110 Reverse Awl
393.100 Universal Chuck with T-Handle
355.041 Guide Rod 3.0 mm,
with flat tip
399.505 Hammer, synthetic
314.280 Holding Sleeve, large
357.360 Extraction Screw for
Spiral Blade
357.117 Hammer Guide for DFN
357.026 Slotted Hammer 400 g,
can be mounted
511.790 Quick Coupling for Kirschner Wires
511.701 COMPACT™ AIR DRIVE II
511.760 Quick Coupling
for DHS/DCSTriple Reamers
511.750 Quick Coupling
117.500 Reaming Instrument Set for
Medullary Nails (not illustrated)
357.133 Extraction Screw for
AFN/DFN

314.750 Screwdriver, hexagonal
357.791 Depth Gauge for Locking Bolts
450.862–872 Locking Screws
459.260–680 Locking Bolts 4.9 mm
450.882–892 Spiral Blade for DFN
451.895 End Cap for Spiral Blade
for DFN
451.896 End Cap for Locking Screw
357.116 Aiming Arm for Spiral
Blade Locking
357.115 Aiming Arm for Standard Locking
351.270 Drill Bit 13.0 mm
357.129 Guide Wire 3.2 mm
357.530 Protection Sleeve 17.0/15.0
357.531 Drill Sleeve 15.0/3.2
357.120 Spiral Inserter for Spiral Blade Insertion
357.132 Connecting Screw for Spiral Blade
351.270 Drill Bit 13.0 mm
357.129 Guide Wire 3.2 mm
357.123 Protection Sleeve 15.0/13.0
357.124 Drill Sleeve 13.0/3.2
450.862–872 Locking Screws
450.862–872 Locking Screws
315.400 Drill Bit 4.0 mm
357.122 Radiographic Ruler for DFN
357.112 Insertion Handle for DFN
357.135 Connecting Screw
321.170 Pin Wrench
451.701–831 Distal Femoral Nail
357.098 Trocar 4.9 mm
357.097 Drill Sleeve 8.0/4.9
357.118 Protection Sleeve 11.0/8.0
357.099 Drill Bit 4.9 mm,
calibrated
314.750 Screwdriver, hexagonal

Synthes 1
Distal Femoral Nail
Table of contents
Warning
This description is not sufficient for immediate application of
the instrumentation. Instruction by a surgeon experienced in
handling this instrumentation is highly recommended.
Image intensifier control
Indications/contraindications 2
Implants 3
Standard locking 4
Spiral blade locking 17
Implant removal 20
Cleaning of instruments 23

Distal Femoral Nail
Indications/contraindications
The Distal Femoral Nail DFN is indicated for the stabilization
of fractures of the distal femur. It can also be used for
diaphyseal fractures in which a retrograde approach is
indicated (e.g. ipsilateral tibia and/or patella fractures,
proximal or distal endoprosthesis, adipositas permagna).
These include according to the AO classification:
Indications
–Fractures of type 33-A1 to A3
–Fractures of type 33-C1 to C3.1
–Fractures of type 32-A to C
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2
Contraindications
–Fractures of type 33-B, 33-C3.2 and 33-C3.3
–Proximal femoral fractures and high subtrochanteric fractures

Synthes 3
Distal Femoral Nail
Implants
Nails
Short and long, for standard locking and
spiral blade locking
Solid: 9.0 and 10.0 mm
Cannulated: 12.0 mm
–Long Nail (451.705–711, 725–731, 825–831)
Lengths: 300, 340, 380, 420 mm
Proximal locking:
1 dynamic hole AP
1 static hole ML
1 static hole AP
–Short Nail (451.701–703, 721–723, 821–823)
Lengths: 160, 200, 240 mm
Proximal locking:
2 static holes ML
Proximal locking
Locking Bolts 4.9 mm, self-tapping
(459.260–680)
Lengths: 26 to 68 mm
Standard locking
For non-osteoporotic bone and simple supracondylar fracture
morphology.
Locking Screws 6.0 mm, self-tapping
(450.862–872) (turquoise)
Lengths: 50 to 100 mm
End Cap for Locking Screw 6.0 mm (451.896)
(turquoise)
Spiral blade locking
For better purchase in osteoporotic bone and for all complex
supracondylar fracture morphologies.
Locking Screws 6.0 mm, self-tapping (450.862–872)
(turquoise)
Lengths: 50 to 100 mm
Spiral Blades for DFN (450.882–892) (pink)
Lengths: 50 to 100 mm
End Cap for Spiral Blade (451.895) (pink)

3
Determine nail length
Position the image intensifier for an AP view of the distal
femur (Position 1). With long forceps, hold the Radiographic
Ruler (357.122) parallel to and on the same level as the femur.
Adjust the ruler until the distal end is at the desired nail inser-
tion depth. Mark the skin laterally.
Move the image intensifier to the proximal femur (Position 2),
place the distal end of the ruler on the skin mark, and take
an AP image of the middle third of the femur (for short nails)
and of the proximal femur (for long nails). Verify fracture
reduction and read the nail length from the ruler image. When
using a long nail, select its length so that it can be locked level
with the lesser Trochanter.
4
Careful preoperative planning with clear classification of the
fracture and correct choice of implants are mandatory for a
successful surgical result.
1
Position patient
Position the patient supine on the operating table. The knee
of the injured leg should be flexed 70°–90°. A leg roll may be
used or the lower leg be flexed by lowering part of the table
to allow proper reduction and stabilization of the reduced
fracture. Position the image intensifier in such a way that vi-
sualisation of the entire femur is possible in anterior-posterior
(AP) as well as lateral views.
2
Reduce fracture
If possible, carry out closed reduction under image intensifier
control. In some cases the use of the Large Distractor (394.350)
is required.
Note: After repositioning, and prior to the insertion of the
nail, intra-articular fractures should be definitely stabilised with
two interfragmentary lag screws. Position the screws so as not
to interfere with the path of the nail. The intramedullary canal
and the nail are slightly dorsal, therefore, lag screws are placed
ventrally.
Distal Femoral Nail
Standard locking
Position 1 Position 2

Synthes 5
4
Determine nail diameter
Place the radiographic ruler perpendicular to the femur and
position it over the isthmus to confirm the nail diameter.
Choose the nail diameter with which the transition between
the medullary canal and the cortex is still visible left and right
of the marking.
5
Incision
For 33-A.X and 32-X.X fractures, either make a transligamen-
tar (ligamentum patellae) or a medial parapatellar incision.
For 33-C.X fractures always make a medial parapatellar ap-
proach.
6
The Distal Femoral Nail may be used for either reamed or
unreamed application.
Determine nail entry point and insert guide wire
The entry point for the nail is in the axis of the medullary
canal and in the intercondylar notch, just anterior and lateral
to the femoral attachment of the posterior cruciate ligament.
Insert the Protection Sleeve 17.0/15.0 (357.530) and the Drill
Sleeve (357.531) through the incision to the bone. Insert the
calibrated Guide Wire 3.2 mm (357.129) to a depth of 10
to 15 cm, taking into consideration the 7° to 9° valgus angle
of the anatomic axis of the femur. AP and lateral image inten-
sifier control is mandatory.
Cortex Cortex
Lateral Medial

6
7
Open medullary canal
Place the cannulated Drill Bit 13.0 mm (351.270) into a
cannulated power drill. Guide the drill bit through the
protection sleeve and over the guide wire to the bone. Drill
to a depth of approximately 30 mm. Remove the protection
sleeve, the drill sleeve and the guide wire. Do not re-use the
guide wire.
Remove the bone and cartilage debris and thoroughly rinse
the knee joint.
Alternative
The medullary canal can also be opened with the Large
Reverse Awl (351.110).
Reaming of the femur may be indicated depending on the
fracture type or if the medullary canal is too narrow. If
reaming is not indicated proceed with step 9.

Distal Femoral Nail
Standard locking
Synthes 7
8
Ream medullary cavity with SynReam (Option)
1Assemble reduction system
Assemble the reduction system of the SynReam Intra-
medullary Reaming System (189.060): Attach the T-Handle
(351.150) at the rear of the SynReam Flexible Shaft
(352.040) and a Reduction Head (352.050 or 352.055) at
the front.

2Reduce fracture
To secure the reduction head, insert the SynReam Reaming
Rod 2.5 mm (352.032, length 950 mm or 352.033, length
1150 mm) in a retrograde direction up to the olive. The olive
must be located in the reduction head throughout reduction.
Insert the assembled reduction system with the SynReam
reaming rod into the medullary cavity and reduce the distal
fragments under image intensifier control.
Note: Always reduce with the reaming rod, since secure fixa-
tion can only be ensured if the reduction system is used in
conjunction with the reaming rod. Using the reduction system
without the reaming rod entails the risk of losing the reduc-
tion head in the medullary canal.
3Remove reduction instruments
After completing the reduction, remove the reduction instru-
ments with the exception of the reaming rod, which must re-
main in the medullary cavity.
8

4Assemble the reaming system
Connect the SynReam Flexible Shaft (352.040) to the drill and
plug the first SynReam Medullary Reamer Head (352.085)
onto the shaft. The reamer heads can be picked up directly,
without hand contact, from the insert for medullary reamer
heads using the SynReam flexible shaft.
Start with the smallest reamer head (8.5 mm, 352.085)
and then increase in 0.5 mm increments using the larger
reamer heads (352.090–190). The reaming depth should be
identical to the chosen nail length.
5Insert reaming system
Insert the assembled reaming system, without rotating it, over
the SynReam reaming rod into the medullary canal. Use the
Tissue Protector (351.050) to spare the soft tissues.
Synthes 9
Distal Femoral Nail
Standard locking

6Ream medullary canal
Ream the medullary canal according to the standard proce-
dure. Advance the reamer slowly and steadily at maximum
drill speed. Secure the SynReam reaming rod with the Holding
Forceps for SynReam Reaming Rod (351.782) to prevent it
from rotating during reaming.
Note: Only ream over the SynReam Reaming Rod 2.5 mm
(352.032, length 950 mm or 352.033, length 1150 mm),
since the rod ensures that a secure connection is maintained
between the reamer and the flexible shaft.
7Change reamer head
Having reamed the medullary cavity along its full length, re-
tract the SynReam flexible shaft with the first reamer head
until the whole reamer head is visible. Grasp the reaming rod
with the Holding Forceps for SynReam Reaming Rod
(351.782) immediately above the bone insertion point and
hold in situ to avoid loss of reduction. Draw the SynReam
flexible shaft through the slot of the Insert with Removing De-
vice for SynReam Medullary Reamers (689.063) so as to re-
move the used reamer head without touching it.
The reamer head of the next size up can be picked up directly,
without hand contact, from the insert for medullary reamer
heads using the SynReam flexible shaft.
10

8Complete medullary reaming
Repeat steps 5 to 7 for each additional reamer head
(352.090–190) until the medullary canal is reamed to the de-
sired diameter. Reaming is usually performed with increments
of 0.5 mm.
Note: Only ream over the SynReam Reaming Rod 2.5 mm
(352.032 or 352.033), since the rod ensures that a secure con-
nection is maintained between the reamer head and the flexi-
ble shaft.
Loosen blocked medullary reamer heads with left-right turns or
with gentle hammer taps to the Holding Forceps for SynReam
Reaming Rod (351.782) fastened to the SynReam Reaming
Rod Ø 2.5 mm (352.032 or 352.033).
9
Attach nail to insertion handle
With the Insertion Handle (357.112) facing laterally, match
the teeth on the handle with the notches in the nail. The
anterior curvature of the implant must be aligned with that
of the femur. Note the inscription ANTERIOR on the nail.
Slide the Connecting Screw (357.135) through the insertion
handle and screw it into the nail. Tighten the connecting
screw with the Pin Wrench (321.170) without stripping it.
Synthes 11
Distal Femoral Nail
Standard locking

12
10
Insert nail
If hammering with the Slotted Hammer (357.026) is necessary
for insertion, attach the Hammer Guide (357.117) to the
connecting screw and tighten the assembly.
Insert the nail by hand as far as possible twisting gently.
When using a guide rod, slide the Cannulated Nail 12.0 mm
over the guide rod into the femoral canal. Monitor nail
passage through the fracture under image intensification.
If necessary, insert the nail using light hammer blows with
either the slotted hammer and hammer guide or with a
Hammer (399.430/399.505). Using the distal end of the
connecting screw as striking surface advance the nail until its
distal end is 2 to 5 mm beyond the articular cartilage. The
insertion depth is indicated by the grooves on the shaft of the
insertion handle. Remove the guide rod.
0
10
5
Note: After nail insertion, check that the connecting screw is
still tight as it could have loosened during hammering. Do
not attach the aiming arm for standard locking or spiral blade
locking, respectively, to the insertion handle until the nail is
fully inserted. Otherwise, the aiming arm may loosen during
nail insertion.
The standard locking is performed with two Locking Screws
6.0 mm (450.862–872).
Spiral blade locking see page 17 (steps 11 to 17).

Distal Femoral Nail
Standard locking
Synthes 13
11
Mount aiming arm and insert trocar assembly
Attach the Aiming Arm for Standard Locking (357.115) to the
insertion handle. Insert the turquoise triple trocar assembly
(Protection Sleeve 11.0/8.0 (357.118), Drill Sleeve 8.0/4.9
(357.097) and Trocar 4.9 mm (357.098)) through the
cranial hole of the aiming arm and, after a stab incision, to
the bone. Remove the trocar.
12
Drill and measure length for locking screw
Drill through both cortices using the calibrated Drill Bit
4.9 mm (357.099) stopping just after penetrating the far
cortex. Confirm the drill bit position radiographically. Make
sure the drill sleeve is in contact with the bone and read the
length for the locking screw from the ringmarks on the drill
bit. The locking screw should not surpass the medial cortex
by more than 2 mm.
Alternative
The Depth Gauge for Locking Bolts (357.791) may be used to
determine the length of the locking screw. Remove the Drill
Sleeve 8.0/4.9 and insert the measuring hook through the
Protection Sleeve 11.0/8.0. Determine the length of the
locking screw by adding 2 mm to the reading on the depth
gauge.

14
13
Insert first locking screw
Insert the locking screw through the Protection Sleeve
11.0/8.0 using the Hexagonal Screwdriver (314.750) and
make sure the screw head is in contact with the medial
cortex. The locking screw should surpass the medial cortex by
at least 2 mm, but not more than 4 mm.
14
Insert second locking screw
Repeat steps 11 to 13 for inserting the second locking screw
in the caudal screw hole on the aiming arm.
Note: For standard locking use two locking screws whenever
possible.

Distal Femoral Nail
Standard locking
Synthes 15
Oval (incorrect)
Round (correct)
Determine
incision point
Proximal locking
Proximal locking for nails of 160 – 240 mm in length is done
using two Locking Bolts 4.9 mm which are inserted later-
ally. Nails of 300 mm or more are provided with a static hole
in lateral direction, and a static hole and a dynamic locking
slot in AP direction. These locking options make immediate or
secondary dynamization of the fracture possible. The AP
approach facilitates locking at the lesser trochanter level.
Align image
Check fracture reduction, the correct alignment of the
fragments, and the correct length of the femur.
Align the image intensifier so that the distal hole is visible as
aperfect circle in the centre of the image.
16
Make incision
Determine the incision point and make a stab incision.
17
Drill
Under image intensification, insert the tip of the Drill Bit
4.0 mm for the radiolucent drive through the incision
and place it on the bone.
Tilt the drive until the drill bit appears centred in the locking
hole. The drill bit will nearly fill out the locking hole image.
Holding the drill in this position, drill through both cortices
until the tip of the drill bit just penetrates the medial cortex.
Alternative
If there is no radiolucent drive available and locking is
performed with the standard freehand technique use the
three-flute Drill Bit 4.0 mm (315.400).
Centre drill bit Drill
15

16
18
Measure length for locking bolt and insert locking bolt
Measure the length for the locking bolt with the Depth
Gauge for Locking Bolts (357.791). The length of the locking
bolt is determined by adding at least 2, but not more than
4 mm to the length read from the depth gauge.
Insert the locking bolt using the hexagonal screwdriver.
19
Insert end cap
The use of the turquoise End Cap for Locking Screw
(451.896) is mandatory. It fulfills two functions: It prevents
bone ingrowth into the nail and blocks the distal Locking
Screw 6.0 mm thus providing a stable angle.
Remove the insertion instruments.
Using the hexagonal screwdriver, align the end cap with the
nail axis and fix it by means of the holding sleeve. To minimise
the chance of cross-threading, turn the end cap counterclock-
wise until the thread of the end cap aligns with that of the
nail. By turning clockwise, completely screw the end cap into
the nail, so that the locking screw is fixed. The last turns will
offer some resistance caused by a groove in the thread which
prevents the screw from loosening. Tighten the end cap
firmly.
Alternative
The end cap can also be inserted after step 14 (page 14).
turquoise

Distal Femoral Nail
Spiral blade locking
Synthes 17
11
Mount aiming arm and insert locking screw
Attach the Aiming Arm for Spiral Blade Locking (357.116) to
the insertion handle. Insert the turquoise triple trocar assem-
bly (Protection Sleeve 11.0/8.0 (357.118), Drill Sleeve 8.0/4.9
(357.097) and Trocar 4.9 mm (357.098)) through the
cranial hole of the aiming arm and, after a stab incision, to
the bone. Remove the trocar.
Drilling, length measuring, and insertion of the Locking Screw
6.0 mm are performed as described in steps 12 and 13 on
pages 13 and 14.
12
Insert double-sleeve combination
Insert the pink double-sleeve combination (Protection Sleeve
15.0/13.0 (357.123) and Drill Sleeve 13.0/3.2 (357.124))
through the caudal hole on the aiming arm. Make a stab
incision and advance the combination to the lateral cortex.
The spiral blade locking option with one Spiral Blade
(450.882–892) and one Locking Screw 6.0 mm
(450.862–872) is used for patients with an osteoporotic bone
structure and/or extensive and complex supra-condylar
comminuted fracture areas. The increased purchase area of
the blade provides an optimized load distribution in the
condyles and improves fixation of the distal fragment thus
decreasing the risk of nail protrusion into the knee joint.
Perform steps 1 to 10 as described on pages 4 to 12.