Otto Bock 17AD100 Nexgear Tango Manual

Technical information 5.2.4
17AD100 Nexgear Tango ankle joint
Fabricating an ankle-foot orthosis and installing the modules

1 Introduction English
This technical information supports you in the fabrication of an ankle-foot orthosis using lamination resin techno
logy.
This document is directed to trained prosthetists. It is a prerequisite that the qualified personnel are trained in the
handling of the various materials, machines and tools.
This technical information does not claim to be exhaustive. Reading this technical information does not substitute
reading the instructions for use for all required products.
1.1 Flowchart
The entire process is shown in the following flowchart. All work steps described in this document are highlighted in
bold.
Plaster model preparation
Place lamination dummy, lamination bar and foot stirrup
Reinforce plaster model
Laminate plaster model and finish orthosis
Install modules
2 Preparation
The following preparations must be made in order to work effectively:
• Collecting the tools and materials
• Performing preparatory work:
Fabricate a plaster model according to individual considerations.
Position the alignment adapter in the plaster model.
Apply the spacer material to the plaster model. (The fitting example shows the use of stockinette.)
Tools
Designation Reference number
Torque wrench 1Nm to 25Nm 710D20
Connecting element 710Y19
Torx wrench set 709S530
Torx bit set 710Y25
Nexgear Tango FIT KIT 17AD100A=FIT-KIT
Materials
Designation Reference number
Orthotic joint alignment fixture 743R6=*
PVC profile bars 17Y106
Perlon stockinette 623T3=*
PVA bag 99B81
Vulkollan elastic band 617B1
Carbon fibre cloth 616G12
Pastasil 85H11=*
2 17AD100
Introduction

Materials
Designation Reference number
Wax pen 633W8
Carbon-fibreglass webbing 616H10=*
Carbon fibre stockinette 616G15=*
Dacron felt 616G6
Quick-drying adhesive 636K11
Polyethylene adhesive tape 627B4
Plastaband 636K8
Double-sided PVC adhesive tape 616F10*
Spray adhesive 636K40
Isopropyl alcohol 634A58
C-Orthocryl lamination resin 617H55
Hardening powder 617P37=0.150
Talcum powder 639A1=1
Comfor Tex soft 623F109
3 Procedure
3.1 Plaster model preparation
Apply contact adhesive to the stockinette above the
alignment adapter and allow it to become touch dry.
Then remove the stockinette above the alignment
adapter.
3.2 Positioning the lamination dummy, lamination bar and foot stirrup
Mount the lamination bar in the lower part of the lamina
tion dummy using 2countersunk head screws.
317AD100
Procedure

Insert the foot stirrup into the lamination dummy cover,
leaving the bearing bushing in the foot stirrup.
Slide the lamination dummy cover with the shoulder
screw onto the lower part of the lamination dummy and
mark the insertion zone on the bar and foot stirrup.
Remove the bar and foot stirrup from the lamination
dummy for machining.
NOTE: Do not machine the insertion zone of the
bar and foot stirrup.
INFORMATION: The foot stirrup is secured in the
neutral position by the design of the lamination
dummy cover.
The neutral alignment of the foot stirrup permits
the maximum dorsal or plantar range of motion in
the orthosis joint.
Mould the foot stirrup and shorten it to the height of the
outside edge of the foot.
Screw the lamination dummy, lamination bar and foot
stirrup to the alignment insert with the shoulder screw.
4
Procedure
17AD100

Check the distance between the lamination bar/foot
stirrup and the plaster model. The minimum distance
must be approx.2to3mm.
Deburr the bar and foot stirrup.
Reinforce the supporting surface with PVC profile
material.
Heat the PVC profile material with a hot air gun and
mould it into shape.
Apply the quick-drying adhesive to the surface to be
glued to the lamination bar.
517AD100
Procedure

Glue the profile material to the lamination bar. Firmly
press the gluing surfaces together.
3.3 Reinforcing
Bar and clamp
INFORMATION: Before reinforcing, roughen the
bar and foot stirrup and clean them using a
degreasing cleaner.
Reinforce the foot stirrup with carbon fibre stockinette,
letting the woven stockinette project approx. 5cm bey
ond the foot stirrup.
Depending on the orthosis construction and the patient-
specific requirements, pull 1 to 3 layers of woven stock
inette over the foot stirrup.
Wrap the reinforcement with an unwaxed thread over
the length of the foot stirrup to form fit the carbon
fibres. Do not wrap the projecting woven stockinette.
Reinforce the lamination bar and PVC profile material
with woven stockinette and wrap with unwaxed thread.
6
Procedure
17AD100

Isolate the following components with wax in the area of
the joints:
• Lamination dummy – lower part
• Bar/foot stirrup insertion zone
• Screws
Connect the isolated components to each other.
Orthosis
Use Plastaband to even out the sharp edges of the
alignment insert.
717AD100
Procedure

Pull a soaked PVA bag over the plaster model.
Apply polyethylene adhesive tape over the alignment
insert so the PVA bag does not tear later while screw
ing on the dummy.
Pull 1 layer of Perlon stockinette over the plaster model.
Apply contact adhesive to the stockinette above the
alignment insert.
After the contact adhesive is touch dry, cut into the
stockinette and expose the thread of the alignment
insert.
8
Procedure
17AD100

NOTE: Use as little adhesive tape or spray adhes
ive as possible, so that the fibres are thoroughly
soaked during laminating.
Secure the carbon-fibreglass webbing to the Perlon
stockinette with some double-sided adhesive tape or
spray adhesive.
• Apply 1 layer of carbon-fibreglass webbing as full-
surface reinforcement from the heel to the rollover
edge in a–p direction.
• Apply 1 layer of carbon-fibreglass webbing as full-
surface reinforcement from the heel to the rollover
edge in m–l direction.
Reinforce to a maximum of 2cm below the ankle joint.
Use carbon-fibreglass webbing to reinforce the load-
bearing areas of the orthosis encompassing the bar and
support surface.
Apply 2 layers of carbon fibre woven stockinette (5cm
wide) in the lateral course of the bar.
Seal the connection zone above the alignment insert
with Plastaband.
Cut the PVA foil above the thread.
917AD100
Procedure

Secure the reinforced components to the alignment
insert using the shoulder screw.
Fan out the end of the carbon fibre stockinette.
Secure the fanned-out fibres to the reinforcement with
carbon-fibreglass webbing.
Fan out the end of the carbon fibre stockinette and
secure it with carbon-fibreglass webbing.
10
Procedure
17AD100

Fill the cavities between the plaster model and lamina
tion bar/foot stirrup with Dacron felt.
Seal and level off all screws and protrusions on the
plaster model with Pastasil.
Pull 1 layer of Perlon stockinette over the plaster model.
Apply 1 layer of carbon fibre cloth in the area of the tibia
support surface.
Optional: Add reinforcement layers according to the
patient's physical and functional requirements.
1117AD100
Procedure

Optional: Fabricate a long foot component.
• Cut 2 layers of carbon fibre cloth to size (fibre ori
entation: 45°).
• Position the carbon fibre cloth on the foot compon
ent.
INFORMATION: A flexible forefoot component is
fabricated in this example.
Position carbon-fibreglass webbing from the heel to the
rollover edge in a-pandm-l direction.
Apply carbon fibre stockinette (5cm wide) in the lateral
course of the bar.
Optional: Position 1 layer of Perlon stockinette and 1
layer of decorative fabric as the final layer or use 1 layer
of carbon fibre cloth.
Prepare templates for this purpose. Transfer the blanks
to the carbon fibre cloth and cut them out.
12
Procedure
17AD100

Secure the blanks on the model.
Then pull a thin stockinette over the model.
INFORMATION: The stockinette prevents the car
bon fibre cloth layers from slipping while pulling
the PVA bag over the model. In addition, the stock
inette ensures that the lamination resin is distrib
uted more quickly over the reinforcement.
Pull a soaked PVA bag over the model and tie it off on
the vacuum tube.
1317AD100
Procedure

3.4 Laminating and finishing
Turn on the vacuum and check the PVA bag to make
sure there are no leaks.
Mix the lamination resin with the hardener.
NOTICE: To avoid overheating during curing, no
more than 1.5%hardener should be added.
Carry out the lamination process.
After the laminate has fully hardened, mark the course
of the edge on the orthosis.
Use a knife to expose the lamination dummy cover and
the insertion zone of the lamination bar.
Remove the Pastasil from the screws.
Unscrew the screws from the lamination dummy and
lamination bar.
14
Procedure
17AD100

Remove the lamination dummy cover.
If the bearing bushing was removed with the lamination
dummy cover, reinsert the bearing bushing into the foot
stirrup.
Cut the orthosis open along the marked course of the
edge using an oscillating saw and remove it from the
plaster model.
NOTE: Use vice jaws to prevent damage to the
product while clamping it in the vice.
Remove the lamination bar from the lamination dummy –
lower part.
1517AD100
Procedure

The shape of the lamination dummy produces the
desired contour to enable the full range of motion of the
orthosis joint without damaging the laminate.
3.5 Mounting the orthosis joint
Check the fit of the bearing bushing in the foot stirrup,
or install the bearing bushing if it is missing.
INFORMATION: Mounting the lower leg component
is not necessary to install the orthosis joint and
individual modules.
Mount the orthosis joint with suitable axial washers:
• Position two axial washers of the same thickness
medially and laterally on the foot stirrup and slide on
the orthosis joint.
• Use thicker axial washers in case of play in the
medial-lateral direction.
16
Procedure
17AD100

Insert the joint screw and joint nut, and tighten with a
Torx wrench.
T20
3 Nm
T20
3 Nm
T25
5 Nm
T30
8 Nm
T30
8 Nm
3.6 Installing the spring-module
Insert the threaded hole through the cover from above
and screw it into the basic piece.
NOTE: Use vice jaws to prevent damage to the
product while clamping it in the vice.
Place the mounting adapter onto the threaded hole and
tighten it to the corresponding torque value.
7AD 00= 0 2 4 6 20
7AD 00A=MA- 0 2 4 20 20
T20 T20 T25 T30 T30
5 Nm 6 Nm 6 Nm 8 Nm 8 Nm
1717AD100
Procedure

Insert the ball into the threaded hole.
Slide the spring into the spring guide housing and posi
tion it in the threaded hole.
Screw the setscrew into the threaded hole and tighten
with a Torx wrench.
18
Procedure
17AD100

3.7 Installing the stop-module
Insert the threaded hole through the cover from above
and screw it into the basic piece so that the flattened
side of the cover faces the basic piece.
NOTE: Use vice jaws to prevent damage to the
product while clamping it in the vice.
Place the mounting adapter onto the threaded hole and
tighten it to the corresponding torque value.
7AD 00= 0 2 4 6 20
7AD 00A=MA- 0 2 4 20 20
T20 T20 T25 T30 T30
5 Nm 6 Nm 6 Nm 8 Nm 8 Nm
Insert the stop sleeve into the threaded hole with the
curve pointing towards the foot stirrup.
1917AD100
Procedure

Screw the setscrew into the threaded hole and set it to
the desired position.
3.8 Installing the reaction-module
INFORMATION: The Nexgear Tango Reaction-mod
ule is delivered installed in the cover. Before the
module can be installed in the orthosis joint, it has
to be disassembled into the individual compon
ents.
Remove the cover cap from the spring bolt.
Press the module out of the cover.
20
Procedure
17AD100