Icelock 544 Technical Presentation

Sarah Mulroy (Clinical Specialist)

AOPA 2016

10/19/2016 1

Icelock 544 Series – 3 valve Systems in 1

• Removing the air between a prosthetic liner and rigid socket compartment (elevated vacuum suspension) has become very common practice in lower limb prosthetics over the past decade.

• Össur currently offers an external socket valve, designed to connect the Unity series of pumps to the prosthesis (UTT0001 and UTF0001). This solution is not always favoured for cosmetic or practical reasons.

• Also have external socket valves for TT and TF seal in systems (L-551000 and L-552001)

• Icelock 544 is a series of valve/adapter solutions, designed to expel air from

- Seal-In systems (vacuum suspension using Seal-in-Liners)- Seal-In and Unity combinations (elevated vacuum suspension)- Cushion/sleeve systems (vacuum suspension)

10/19/2016 2

Features and benefits

Feature BenefitEasy and fast fabrication Significant time savingsIn-line solution No protrusions on the sides of prosthesisModular and flexible design Details with vacuum and/or expulsion can

be changed and interchanged after fabrication

10/19/2016 3

Basic structure (Unity Example)

10/19/2016 4

Configurations

• Icelock 544 Series offers 3 configurations utilising same socket adapter:

L-544611 is designed for Unity (Grey plate) Contains Push button and bard for Unity hose

The expulsion-only check valve, which is suitable with the simplest form of a Cushion-Sleeve setup, where only expulsion is desired

L-544621 has an exhaust filter instead of a barb connector, used with Seal-In expulsion setup (Orange plate)

10/19/2016 5

How it Works: Unity plate used as an example

• Socket Adapter L-544400 is set up on socket along with selected valve configuration

• Air is pushed through a hole distally in socket (BLUE arrow)

• A brass filter traps any solid particles, protecting system and vacuum pump (RED arrow)

• Air continues towards exhaust port (GREEN arrow)

• Air is vented towards pump or to air via a check valve (YELLOWarrow)

10/19/2016 6

Dimensions

• Valve plates are 9.5 mm high.• L-544400 adapter is 16 mm high, diameter 72 mm• Standard 4-Hole adapters are mounted directly onto the valve plate• Valve plate kits contain M6x25 mm screws, matching all Össur 4-Hole adapters

10/19/2016 7

Socket configuration and adapter placement

• An imperative feature for successful Icelock 544 Series setup is to use rigid thermoplastic inner sheath for the socket, preferably PETG.

• 3 mm PETG is recommended for the inner surface of a laminated socket, and thicker PETG is good for test sockets

• This essentially turns the check socket fabrication and definitive socket fabrication into one single effort, which can save time

10/19/2016 8

Test Socket Adapter placement

• L-544400 socket adapter is supplied with a white dummy already mounted into it.• Keep it in place when bonding the socket adapter to the socket.

FSX80016 is the preferred material to seal an Icelock 544 series adapter to a socket.

• The flexibility of FSX80016 allows slight movements, which are always present in prostheses and will not show microcracks later on. A mix of talc and resin can eventually crack and leak.

• Generously fill top of the adapter with adhesive. Cover adapter holes and fill center section completely before lowering socket onto adapter. Allow to set for a few minutes.

10/19/2016 9

Test Socket

• Reinforce a test socket with casting tape before weight bearing

10/19/2016 10

Drill hole

• Whether making a test socket or a definitive socket, drill through dummy using a sharp 3 mm drill bit and all the way into the positive cast before removing them and proceeding to assembly.

Test socket Definitive socket

10/19/2016 11

Lamination Process

Drape with 3mm PETG

Roughen up outside of PETG with sandpaper

Insert lamination dummy into plate

Insert putty into holes, and apply small amount of release agent onto surface of dummy

10/19/2016 12

Lamination Process

Apply electrical tape into the groove to protect the plate

Apply generous amoount of FSX80016 adhesive

Lower the positive with plastic onto the plate

Allow adhesive to set

10/19/2016 13

Lamination Process

Remove electrical tape and the 4 hole adapter

Apply lamination dummy (differs from photo)

Tie first layer into groove of plate, then tie it a second time around adhesive area

Reflect first layer of carbon. Repeat for desired lay up

10/19/2016 14

Lamination Process

Turn PVA bag inside out for a glossy finish and pull over layup

Pour resin into the bag

Allow vacuum to pull resin down for the first 3-5cm

Continue then to string resin down

10/19/2016 15

Lamination Process

Apply electrical tape to the bottom portion of the lamination dummy to remove any resin from the edge of the plate

After resin has set remove tape and PVA bag

Remove the excess resin and dummy

10/19/2016 16

Use a 3mm drill bit to drill through bottom of plate to plaster cast, using the drill hole in the dummy as a guide

Insert appropriate seal or duck bill valve and apply housing

Select expulsion valve, seal in or unity plate, apply and add 4 hole adapter of choice

Lamination Process

10/19/2016 17

Assembly

• The larger seal/O-Ring goes on top of the valve plate and seals towards the housing/adapter assembly.

• Use the 4 supplied M6x25 screws for this assembly.

10/19/2016 18

Maintenance

• The only known maintenance issues with Icelock 544 are potential dirt and contamination issues.

• A complete teardown and rinse with Isopropyl alcohol, and/or soapy water is usually the best approach if a quick blowout with compressed air does not do the trick.

10/19/2016 19

Problem Solving

• Potential leak points, if at all, are typically found along the red line in the illustration to the right. The risk of leakage is very low when the fabrication of Icelock 544 has been done correctly.

• PETG is needed in the fabrication process. Icelock 544 series is designed to utilise this inner surface and seal against it.

• If screws are too long they may pop the adapter off and compromise the seal. Ensure the holes are free from debris also

• If this occurs, restart the process form the point of bonding the adapter onto the socket to ensure the adapter is fully resealed.

• Ensure all seals are free of dirt when assembled and seated in the right position

• Apply a little compression on them when assembling, it is normal to compress the seals 0,.5-1 mm when assembled.