Instructions and Sizing


Applying Thumb Splint

Mckie Splint Instrutions

Step 1: Put the thumb through the thumb hole. Orient the splint so that the stitching follows the crest of the web between thumb and index finger. Snug to fit comfortably. Draw the strap of the splint at an angle so that it drops below the corner of the palm. (For medical personnel, it sits below the pisiform bone). Pull the split strap so it continues around the back of the hand all the way around again to the palm side.

Step 2: Depending on your intent, you can attach the hook tape in either of 2 ways:

Option A: If you are experiencing thumb pain or arthritis at the base of the thumb (C-M-C joint), direct the pull of the strap up into the base of the thumb metacarpal as illustrated.

Option B: If you are attempting to improve grasp quality, attach the hook tape to put mild pressure on the head of the thumb metacarpal.

Applying Supinator Strap – Self-Attachment Above Elbow

Mckie Supinator Stap

Step 1: To attach supinator strap, undo strap from thumb splint. Reattach thumb splint over supinator strap. (figure 3)

Step 2: Wind one turn around forearm, then one turn behind elbow. Attach wider, squared hook tape end of strap to itself above elbow (figure 4). The splint is designed to assist forearm extension, so supinator strap must cut across the back of elbow.

Step 3: Once splint is in place, passively turn forearm palm up (supination) and slightly extend wrist (figure 5). Make any necessary adjustments to supinator strap to ensure a snug fit. The attachment above the elbow, while snug, should be comfortable, balancing good coloration of the hand with some pull from the strap.

Step 4: Finally, check the hand splint and, if necessary, rotate it to ensure the thumb is positioned to oppose fingers.

Always follow precautions on label regarding splint application and wear.

Fitting Thumb Splint and Adjustable Supinator Strap

Both the strap of the Thumb Splint and the Adjustable Supinator Strap may be shortened to accommodate different size hands or to compensate for some loss of elasticity in the straps that occurs over time.

Thumb Splint

If after trying the on the splint, the splint strap and velcro protrude beyond the thumb, cut strap and/or hook tape to fit the hand.

Supinator Strap

The squared end of the supinator strap may be cut to fit a shorter or narrower forearm. Attach free piece of hook tape to the squared end of strap.


Sizing for Adults and Children

To assure the best fit, use of a sizing kit is strongly recommended. If a sizing kit is unavailable, follow the directions below. Neonatal sizes are suitable for very small or prematurely born infants. Pediatric sizes are suitable for children from about 3 months to 6-10 years. Older children and adults need adult sizes. When figuring sizes, it is important to use a centimeter tape measure.

How to Determine Thumb Splint Size

1. Measurement A

Measure to the 1/10th of a centimetre the circumference of the far or distal thumb joint.

2. Measurement B

Measure to the 1/10th of a centimetre the distance on the palm from the distal thumb joint to the centre of the wrist crease.

3. Refer to Chart

On the appropriate chart (see links below), find the the square where Measurement A and Measurement B meet. The square should fall within a bold area corresponding to the correct size. If Neonatal use only Measurement A Neonatal Sizing and refer to the neonatal chart for neonatal sizing.

Example: If Measurement A = 5.2 centimetres and Measurement B = 6.0 centimetre, then splint size = P5

  • Adult Sizing Chart →
  • Paediatric Sizing Chart →
  • Neonatal Size Chart → Use only Measurement A. Refer to the neonatal chart for neonatal sizing.

4. Record Sizes

Note splint size and left or right hand, as this is required when ordering. If ordering offline, the catalog # for the above example would be P5-L (left hand) or P5-R (right hand).

How to Determine Supinator Size

When figuring sizes, it is important to use a centimetre tape measure. All supinator straps may be shortened.

  • X-Small (7/8 inch x 15 inches) straps are typically needed by infants.
  • Small (1 inch x 18 inches) straps fit toddlers through about 6 years.
  • Medium (1 1⁄2 inches x 24 inches) straps fit larger children, young teens and smaller adults.
  • Large (2 inches x 30 inches) straps fits most adults and older teens.