Össur 4SEAL TF Technical Manual página 6

Selecting the liner size
Measure the residual limb circumference 4cm above the end of the residual limb. Ensure that any overhanging soft
tissue is taken into account (Fig. 1)
Select the 4Seal liner according to the selection table and reduce up to one size depending on the soft tissue
conditions.
Depending on the residual limb situation, it may happen that the selected liner still does not fit. After putting on
the liner, you should absolutely check the fit and adjust the liner size if necessary.
APPLICATION
Cleaning
Before using a new Össur Liner for the first time, it should be carefully washed and dried 2-3 times. This reduces
the initially high adhesion of the material, which may cause skin reactions in the case of sensitive skin.
Trimming the liner
• Trimming of the silicone liner must be carried out with special care. No corners, edges and folds may develop;
these can lead to tears in the material and/or to skin problems. A wave cut must be performed on the cutting
edge to reduce the surface tension (Fig. 2)
• Please ensure a properly fitting trim over the edge of the shaft so that the cutting edge does not extend into the
crotch area.
CAUTION: Rolling the 4Seal TF liner over the shaft edge is not possible because the Easy Glide Plus coating would
then be damaged and adhesion to the skin is no longer guaranteed.
Trimming the liner and preparation of the plaster cast
Note: Please observe the detailed processing information in our information about the shaft design.
Mark the planned upper shaft edge on the liner and perform the trim. We recommend using wave-cut scissors.
Keep the liner on the residual limb for a while in order to be sure to that the user feels comfortable with it.
Because of the Easy Glide Plus coating, sealing the cut edge with silicone adhesive is not necessary.
Make sure that the distal end of the liner is centered on the residual limb and that the sealing lips are in the correct
position perpendicular to the residual limb axis.
Draw the usual guide lines and markings for circumference measurements. Make the normal length, width and
circumference measurements and write them down on a dimension sheet. In order to subsequently obtain an
optimum fit and a functional vacuum, it is imperative to precisely determine the circumference dimensions. They
serve later as a basis for further reductions in volume.
Plaster cast
Draw the usual guide lines and markings for circumferential measurements. When making the mould, be sure to
accurately shape the area of the seals.
Modeling the positive
Estimate the necessary volume reduction. Based on the measurements taken for the patient, we recommend a
reduction of 1-3% proximally extending to 0% distally.
The volume is one of the most important factors for the fit of the shaft. Work especially carefully in this area.
Reduce as calculated above.
Note: Please completely smooth the molded profile in the area of the sealing lips. Neither a circular volume
increase nor a significant reduction in volume is to be carried out in this area.
Similarly, a smooth shaft interior surface is especially important to obtain a good seal.
Notes regarding shaft design
Create a shaft with the usual techniques. All PETG test shaft materials, laminated shafts and a number of
thermoplastic inner shaft materials with a smooth surface are suitable.
To achieve a smooth surface on the plaster model, we recommend the use of fine abrasives for smoothing after
modeling, followed by use of silicone spray.
In order to ensure long-term functioning of the sealing lips, we recommend the following shaft materials:
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