When you are handed a script that reads “splint fabrication,” does panic set in? What type of splinting material should you choose? Are you one of those therapists overwhelmed by today’s choices in splinting materials? Why do we have and need so many choices? How do you know which is the best splinting material choice for your patient?

I get asked these questions all of the time. However, we are lucky to have so many choices in splinting materials today, because there is no one magic material to handle all of our needs. For example, we make rigid long arm splints and anti-spasticity splints, and the splinting material for these types needs to be fairly thick and strong.

We also fabricate thumb splints or splints for infants and young children, and these splinting materials need to be thin, and lightweight, yet supportive. We also make dorsal-based hand and finger splints from very conforming materials.

As you can see, there is no splinting material which will cover all our needs or satisfy every splinting situation. In order to make the best choices in our splint fabrication, it is essential to understand the properties and qualities of these materials.

Low-Temperature Thermoplastic Materials (LTTPs)

The splinting materials used to fabricate splints today are referred to as low temperature thermoplastics (LTTPs) because they are activated using relatively low heat (water between 140 degrees to 170 degrees Fahrenheit) as compared to other high-temperature thermoplastics which require higher activation temperatures (greater than 250 degrees). We can place these LTTPs directly on our patients while we are molding splints.

There are so many types and varieties of LTTP splinting materials available today from multiple manufacturers and distributors. It is equally important to know and understand the correct splint design for your patient’s diagnosis and to select the proper LTTP for that particular splint. This ensures that your custom made fabricated splint is not only procedurally correct, but also supportive, durable, and comfortable. Patients will tend to be more compliant with a comfortable and properly fitting splint.

Describing LTTPs

Most manufacturers will provide descriptions of their splinting materials, and they commonly use terms like rigidity, memory, bonding, resistance to stretch, conformability, and more. These terms refer to the working properties of splinting materials. Here is a glossary of important terms to understand about splinting materials.

1) Rigidity refers to the strength of the material. High rigidity is necessary for large splints, specific diagnoses such as spasticity, and splints projecting large forces.

2) Memory is the ability of the material to return to its original size and shape after being stretched. This is an important concept when frequent remolding of the splint will be necessary, as in serial splinting to increase extension or flexion over time. Memory makes the material more cost-efficient.

When working with materials possessing excellent memory, remember to let the splint harden sufficiently before removing or it will lose its shape rapidly. Also LTTPs with excellent memory tend to take longer to harden, so be patient! 

3) Conformability or drapability refers to the way the material conforms to the shape of the hand. Materials with high drapability work best with gentle handling, as they conform easily to the arches or bony prominences. Let gravity assist you.  Materials with low drapability require firm handling and are recommended for larger splints where this moldability is less important.

4) Elasticity, or resistance to stretch, refers to the amount of resistance the material gives to being stretched when heated. High resistance means you must work slowly and steadily to stretch the material. Low resistance to stretch means you need to work more quickly and carefully to control the material as it stretches. Elastic materials conform exceptionally well when stretched.

5) Activation temperature is the temperature at which the splinting material becomes pliable for molding. If the water is too cool, the material will not become pliable. If it is too hot, the material will get overheated, sticky, and difficult to work with. The ideal temperature for most LTTPs is between 140 degrees and 160 degrees F. Please read the manufacturer’s directions for each individual LTTP.

6) Coating is applied to certain LTTPs to make them easier to work with and less likely to adhere together where no adherence is desired. Coated materials and non-coated materials each have advantages and disadvantages. The coating can be removed when desired. It is important to know how to remove the coating correctly from different types of materials.

7) Perforations in the splinting material allow for ventilation of the skin and make the material lighter in weight. Today we have choices ranging from percentages of perforations to various names of perforation patterns. Catalogs usually feature pictures which demonstrate the different perforation patterns. Always check to make sure the perforation style is suitable for the splint you are making.

8) Thickness of a LTTP must be taken into consideration as well. Thinner materials such as 1/16-inch and 1/12-inch are generally better for smaller splints, while larger splints may need thicker materials, such as 1/8 inches or 3/32 inches.

I try to use the thinnest material to get the job done, making the splint less heavy for the patient. Thinner LTTPs soften and harden more quickly than thicker materials, meaning they have a shorter working time. Sometimes you can use a thinner material for a larger splint if you make the splint circumferential as this type of splint includes stability in the splint design.

9) Working time describes the amount of time from when the material is fully heated to when it is cooled off. Novice splint makers may want to choose materials that have a longer working time, while advanced splinters can usually work quickly and accurately with LTTPs that cool and harden quickly.

Elastic vs. Plastic

Another way to classify splinting materials is by their core properties – elastic versus plastic. We can easily determine the differences. Elastic splinting materials turn transparent in the hot water, can be stretched out quite a bit, and have excellent memory. They conform best when stretched to fit. Plastic materials also conform very well, but they have no memory. Once you have stretched them, there is no turning back, so be careful with handling. 

Determine which material you like best for different splints, but make the material work for you. Really stretch the elastic so that it conforms, or let the plastic drape with gravity. Know what you can and cannot do with the selected material to make a well-fitting splint.

Other Important Facts

LTTPs do have a limited shelf life, as these materials are made from organic components that are vulnerable to environmental factors. UV rays, heat and humidity, bacteria, and germs can all have a negative effect on the thermoplastic material causing breakdown. Always store your splinting materials flat in a dry, dark place for maximum benefit.

Most LTTPs will absorb dirt and micro-organisms over time.  These penetrate the material and cause unpleasant odors and discoloration. It is important to teach your patients to wash their splints daily with soap and lukewarm water.  Avoid strong detergents, acetones, and solvents, as these can negatively affect the splinting material.

Helpful Hints for Working with all LTTPs

1. Carefully monitor the water temperature and do not overheat the material! Overheating is the No. 1 problem with splinting materials. They can become overstretched and sticky if your water is too hot.

2. Promptly remove the LTTP when activated. Too much heating can also make the material difficult to work with.

3. Properly remove coating from coated materials to attach outriggers. Check to see if you should use solvent, or scrape off coating with your scissors.

4. Cut out patterns from material that has only been partially heated. Then fully reheat the material before molding the splint on your patient.

So now you hopefully have a better understanding of splinting material properties and why we need so many different types. When it comes to proper selection, you are going to be guided by this knowledge as well as by the type and design of the splint, the needs of your particular patient, and, of course, by your own preferences! Yes, everyone has their own favorite material for a specific splint design or pattern.

A Circumferential Wrist Splint

I am going to share instructions for a wrist splint that is one of my favorite splints to fabricate.

For this splint you need to use a 1/12-inch or 1/16-inch splinting material that is elastic, coated, and preferably micro- or lightly perforated. Circumferential wrist splints can be made from lighter and more perforated materials than typically used for volar or dorsal wrist splints. That is why I think they are tolerated so well.

This splint design will work for patients with wrist sprains, strains, tendonitis, arthritis, and/or post fractures. The pattern is essentially a square or rectangle of material wide enough to cover the widest part of the patient’s hand and forearm.

The following instructions and figures from The Splinting Guide by Paul Van Lede will help guide you – Happy Splinting!


1. A small hole for the thumb is cut exactly in the middle of the material about 1 ½ inches from the distal edge. The material is heated up and carefully lifted from the splint pan. Hold by both upper corners with the thumbhole position at the top and centered. 

The patient should be seated with their elbow supported on the table. Work on the ulnar side of their forearm. Carefully position the material over their hand with the thumb centered in the hole.



2. Pull their thumb through while pulling the material ulnarly. Pinch the distal edges together. Then pull the proximal edge of the material down and pinch again on the ulnar border.








3. Make a firm pinch line along the entire ulnar border of the wrist and forearm.












4. Make sure to position the thumb in a functional position.











5. Trim off the excess material while the material is semi hardened.












6. Attach three straps to complete the splint. One should be proximal, one should be distal, and one should be placed in the middle









References

Van Lede, P. (2003). The Splinting Guide. Orfit Industries NV, Belgium.

Schwartz, D. (2008). A Guide to Choosing the Proper Splinting Material for Your Splints. www.exploringhandtherapy.com. Volume 8, Issue 3. July – September.

– Debby Schwartz, OTR/L, CHT is a hand therapist as well as a product and educational specialist with Jericho, N.Y.-based Orfit Industries America. She has joined Orfit Industries America to promote product awareness and splinting education through splinting workshops for beginner and advanced splinters.

Contact Debby at debby.schwartz@orfit.com to find out about attending or hosting an Orfit Industries America sponsored splinting workshops. Other questions and comments can be directed to editorial@therapytimes.com.