What is it?

You may have noticed that your child’s injured arm rests in a ‘thumb-down’ position, (Figure 1), while the other arm rests ‘thumb-up’. The Sup-ER splint has been designed to help support a ‘thumb-up’ position by maintaining the length of your child’s arm and shoulder muscles (Figure 2).

Just like your child, the splint is one of a kind! It is comfortable, easy to use, removable, and can be adjusted for growth. The splint is made of a lightweight plastic material shaped on your child’s arm, and a special strapping system.

How do I put the splint on my child?

Part 1

  1. With the palm facing up, apply the plastic splint (as labeled) to the inside of arm/hand (see Figure 3).  

  2. With the palm still facing up, apply the white elastic strapping.  Start with the end pointing into the palm (Figure 4), looping around the hand and through the thumbholes, twice.
  3. Continue to wrap the strapping up over the arm splint (Figure 5).
  4. Overlap by half the strap width.
  5. Apply gentle even tension. 

Goal: The elastic strapping helps reinforce the palm-up position.

Part 2

  1. Apply the waistband, pulling the Velcro strap up between the legs, just like a diaper (Figures 6 & 7).

  2. Gently turn the shoulder outward (thumb pointing out, Figure 8). 
  3. Attach the Velcro straps (as labelled) at top of the arm and elbow, securing to back of waistband (Figure 9).

Note: Always position the shoulder with your hands. Do not use the strapping to pull the shoulder into position.

Goal: The strapping supports the outward shoulder position.

When should the splint be worn?

  • 22 hours per day to start.
    • We will review your child’s progress monthly. Reducing the time required in the splint will depend on your child’s overall development, and arm strength and flexibility.
  • Remove the entire splint twice per day, for one hour each in morning and evening.
    • Use these breaks for bathing, stretching exercises and play time.  
  • Remove the strapping for Part 2 when your child is eating or traveling in a car seat.

What do I need to check?

  • Check finger color on a regular basis (especially as your child is getting used to using the splint).  
    • Fingers that are dark purple or white mean there is poor blood flow to the hand, and the strapping may be too tight.  
    • Remove the splint immediately; allow color to return to normal, and then reapply, checking strap tension.
  • Check the skin for redness or irritation, whenever the splint is off.
    • Redness that disappears within 20-30 minutes is acceptable.  
    • Contact your therapist if there is any persistent redness or irritation.

How long will my child need a splint?

We recommend use of the splint for some portion of the day and/or night (as directed), for the first year of your child’s life.

Should I clean the splint?

Yes! A clean splint helps keep skin healthy.

  • Wipe the arm splint every day with a damp, soapy cloth.
  • Hand wash the waistband and strapping, as needed. Hang to dry.

What else should I know?

  • Do not leave the plastic splint near any heat source – it may lose its shape and no longer fit properly.
  • Be consistent. Your child will adjust to the splint more quickly if worn regularly.
  • Do the stretching and play activities, as recommended. The splint does not replace these.  
  • More information about brachial plexus injuries, stretching exercises, and play activities are located in your information package. The package also includes more pictures and a splint use log.

Fig. 1: Arm position.

Fig. 2: Sup-ER Splint.

Fig. 3 

Fig. 4

Fig. 5

Fig. 6

Fig. 7

Fig. 8

Fig. 9




Sup-ER Splint Videos:

Sup-ER Splint - Assembly (for parents and clinicians)

Sup-ER Splint - Fabrication (for clinicians)


Sup-ER Splint Guide for Parents

Pictures of Sup-ER Splint application (Parent Handout)

Instructions for Wearing the Supination Wrap Strap

Modified jacket pattern

Range of Motion Exercises for Infants

Splint Wear and Care