Appropriate Fit: The Key for Successful Use of Prefabricated Upper Extremity Orthotic Devices

Lynn Thibault Toni Thompson

The goals of upper extremity orthotic devices, custom- made or pre-fabricated, include enhancing function, improving position, and preventing deformities for the child and adolescent with cerebral palsy, arthrogryposis, or other neurological, orthopaedic, or congenital condition.

Pre-fabricated orthotic devices, from a variety of manufacturers, can provide appropriate positioning for the wrist, hand, fingers, and thumb to enhance function. The pre-fabricated devices often do not offer appropriate fit in their basic off-the-shelf form.

Several keys points with attention to the bony prominences and anatomical landmarks must be incorporated to effectively fit the orthotics devices. Adaptations can help to insure appropriate fit.




Keys to appropriate fit:

  1. Adequate length. The splint should cover 2/3 the length of the forearm to allow for adequate distribution of pressure.

    1. NOT TOO SHORT. A short forearm component can increase the amount of pressure. If the force on the forearm is not distributed well enough to counterbalance the resistance of tone of the wrist flexors, the splint may not provide adequate support and result in a deforming position of the wrist. (Hogan, p. 15-16) (Jacobs and Austin, p. 59-62.)

    2. NOT TOO LONG. A forearm component that is too long may result in the inability to flex the elbow and potentially cause red marks and bruising on the elbow or upper arm.

  2. Adequate digit function. For adequate movement and function of the metacarpals (MPs), the Distal Palmar Crease should be free. (Coppard, p. 51-52) (Hogan, p. 10) (Jacobs, p.30-31).

    1. The extended distal aspect of the splint blocks the MP into full extension, and allows interphangeal joints (IPs) to flex, causing a deforming position of the digits.

  3. Adequate wrist position. Adequate wrist support helps to maintain wrist in neutral in terms of radial and ulnar deviation.

    1. A loose forearm trough allows the wrist to migrate into ulnar deviation, a potentially deforming wrist position.

    2. A trough that is too wide does not provide adequate wrist support, allowing ulnar deviation.

  4. Adequate wrist-digit position. The degree of wrist extension necessary for function can vary from the actual available ROM of the wrist. The digits must be functional, and sometimes this involves maintaining the wrist in neutral or slight flexion rather than maximum available wrist extension.

  5. When the digits are flexed and unable to extend, a good solution is modify the splint to include increased wrist flexion.



Keys to appropriate fit:

  1. Adequate length. Correct proximal and distal length provides adequate support and distributes pressure by incorporating contact with sufficient body surface (Jacobs 59-62).

    1. A fulcrum that is too short can cause discomfort and fail to adequate maintain the wrist in optimal position. (Jacobs, p. 61)

    2. A long fulcrum can interfere with joint motion and movement.

  2. Adequate width. Snug wrist fit supports a neutral position in terms of ulnar and radial deviation.

    1. Loose wrist fit and loose straps contribute to an ulnar deviated position.

  3. Adequate digit position. A balance between wrist extension with some digit flexion is optimal

    1. When IPs are hyperextended, a better choice to decrease the amount of wrist flexion and allow more MP and IP flexion.



Keys to appropriate fit:

  1. Adequate thumb component length. In many cases, the thumb component can be trimmed down to allow for IP movement.

    1. The standard thumb component may be too long and inhibit functional use of the thumb.

  1. Adequate web space fit. Assure that the glove is fitted and pulled down snugly into the web space.

    1. Poor fit into the web space does not adequately support the web space,
    2. leading to hyperextension of the thumb MP with decreased functional use.

  2. Adequate function. Manipulation of objects using various types of grasp and pinch are good tests for a functional splint.

Conclusion: Most splints cannot address both functional movement and immobilization for positioning. In the team approach to pediatric orthopaedics, the responsibility of the orthotist is to:

  • Work with the team to Determine the goal of the splint, and
  • Choose each splint for the of the child to meet the pre-determined goals

Prefabricated splints require attention to the specific details and individualized adjustments to meet each child's anatomy and functional needs.



Coppard, B.M., & Lohman, H. (2001). Introduction to splinting: A clinical–reasoning and problem-solving approach. (2nd ed.). St. Louis: Mosby.
Hogan, L., & Uditsky, T. (1998). Pediatric splinting: Selection, fabrication and clinical application of upper extremity splints. San Antonio: Therapy Skill Builders. (out of print)
Jacobs, M., & Austin, N. (2002). Splinting the hand and upper extremities. Baltimore: Lippincott, Williams & Wilkins Publishers.
Barr, N.R., & Swan, D. (1988). The hand: Principles and techniques of splinting the hand. (2nd ed.). Boston: Butterworth Heineman Publishers.
Casey, C.A., & Kratz, E.J. (1988). Soft splinting with neoprene: the thumb abduction supinator splint. American Journal of Occupational Therapy, 42(6), 395-398.
Exner, C, & Bonder, B. (1983). Comparative effects of three hand splints on bilateral hand use, grasp, and arm-hand posture in hemiplegic children: A pilot study. Occupational Therapy Journal of Research, 32, 75-92.
Goodman, G., & Bazyk, S. (1991). The effects of a short opponens thumb splint on hand function in cerebral palsy: a single subject study. American Journal of Occupational Therapy, 45(8), 726-731.
King, S., Thomas, J.J., & Rice, M.S. (2003). The immediate and short-term effects of a wrist extension orthosis on upper-extremity kinematics and range of shoulder motion. American Journal of Occupational Therapy, (57)5.
Langlois, S., Pederson, L., & MacKinnon, J.R. (1991). Hand splints and cerebral spasticity: A review of the literature. Canadian Journal of Occupational Therapy, 56(3), 113-119.
Einbond, A., Glover, J., Goldberg, S.R., & Takai, V. (1981). A survey of rationales for and against hand splinting in hemiplegia. American Journal of Occupational Therapy ,35, 83-90.
Schultz-Johnson, K. (1996). Splinting the wrist: mobilization and protection. Journal of Hand Therapy, 9, 165-176.
Trombly, C., & Radomski, M.V. (Eds.). (2002). Occupational therapy for physical dysfunction. (5th ed.). Baltimore: Lippincott, Williams, & Wilkins.
Wallen, M., & O'Flaherty, S. (1991). The use of soft splint in the management of spasticity of the upper limb. Australian Journal of Occupational Therapy, 38(15), 227-231.
Wilson, G. (1997). Custom Neoprene Splints for Upper Extremity Disorders. ADVANCE for occupational therapy practitioners. December 1, 1997.
Wilton, J.C., (1997). Hand splinting principles of design and fabrication. Philadelphia: W.B. Sanders.